Significant Papers on Solar Forcing of Climate Since 1987, excluding papers on cosmic rays and climate (Working List/Resource)

crcFig1

A graph of the correlation between historical monsoon rainfall and circulation and solar activity. From Neff et al. 2001.

NOTE: All relative terms (e.g., recent decades, recent global warming) are relative to the respective times of publication of each of these articles.

As with all my lists of this type, most of the papers on it agree with the climate realist perspective on climate change, as defined on the About page. (In this case I think that would mean accepting a large solar forcing on climate and multiple solar amplification mechanisms.) This is because the purpose of all these lists is to show that the climate realist perspective is supported by a substantial portion of the scientific literature.

Also note that these papers have yet to be organized into correct monthly order.

Paper Count: 326 (more but I need to recount it)

 

I have often heard it claimed that the Sun could not be responsible for the recent global warming, and also heard it contended that solar activity doesn’t influence climate very much, at least not very much except on very long timescales, as well as that the only forcing from the Sun is from TSI (total solar irradiance, or brightness) variations (see below for more on that). It’s been asserted that the scientific literature supports these views as well. In fact, the IPCC doesn’t believe solar activity was a significant player in climate change since 1750. As with the IPCC’s position on cosmic rays, I respectfully disagree. Though papers and scientists do support such claims, and the IPCC does important and helpful work with help from many scientists, I cannot be sure that they are a majority, and there are many papers documenting ways solar activity could be at least partially responsible for the recent warming, how shorter solar cycles can influence climate to a very large degree, and how even small variations in solar activity can be amplified by the Earth’s climate system to produce a large climate response.

Thus, I present a list of select, significant papers on some aspect of solar forcing of the climate of our home planet that were published since 1987, with the exception of those that focus on some aspect of the cosmic ray-cloud connection.  Also given is the reason why I chose to include them. Note that I have chosen not to list a good amount of papers because they were written before 1987 or aren’t significant enough to include. Some papers are not included because the journal they are published in is not reputable (see my climate science journal list). Also note that I do not necessarily endorse the findings of these papers, nor do I endorse the opinions of the scientists who wrote them.

However, before listing these papers I believe it is important to have background knowledge. There exist many correlations (see papers below) between climatic, hydrologic, and atmospheric variability and solar activity of some kind. Since many of these correlations cannot simply be explained by the direct radiative impact of TSI changes alone, a mechanism is required (unless the correlations are spurious, which is unlikely, considering how many there are) by which some aspect of solar variability can be translated to the earth’s climate, atmosphere, oceans, etc. To be sure, TSI variability has a role in climate change, but it alone couldn’t explain all the observed correlations. There are many such mechanisms that have been proposed, many of which are listed below.

Some background knowledge about solar activity variations is also important to have, in my opinion. The Sun’s activity varies in different solar cycles. It is not a constant entity. Its magnetic field, irradiance, flare numbers, etc. vary in sync with different cycles that the Sun is undergoing constantly. Though the 11-year Schwabe solar cycle is the best understood, there are many other possible solar cycles that, if existing, could influence climate significantly. Such cycles are of many periodicities, including the 22-year Hale cycle, the ~87-year Gleissberg cycle, the ~210-year de Vries/Suess cycle, and the ~2300-year Hallstatt cycle, to name a few. Cycles of these periodicities have been found in paleoclimate records from around the world. If these cycles are real and any of them are correlated with temperature rise over the 20th century, then the Sun could explain more warming than it’s commonly given credit for. But, to find out if this is the case, more work is needed to be done on this topic.

 

Now, I will discuss some of the proposed amplification mechanisms, by which solar activity influences certain climatic variables, which in turn influence other climatic variables, which in turn influence yet other climatic variables, and so on, providing a positive feedback and an amplification mechanism.

Many papers on the list discuss the Top-Down solar amplification mechanism. It is one where solar ultraviolet variations (solar UV varies more than TSI over a given solar cycle) influence ozone (which is a greenhouse gas) concentrations in the stratosphere, and through the ozone variations’ influence on other climatic variables, the solar signal is transmitted all the way to earth’s surface and amplified.

Several papers on the list talk about the Bottom-Up solar amplification mechanism. It is one where the Sun, the ocean, the atmosphere, and climate are coupled. One regional example is by a process where increased solar activity influences the Walker Circulation (an important component of atmospheric circulation: the movement of air, which, along with oceanic circulation, transports heat around the globe) tropical Pacific precipitation, cloud cover, upwelling, and SSTs (see the work of Drs. Harry van Loon and Gerald Meehl).

Interestingly enough, several regions seem to be sensitive to solar forcing (e.g., the tropical Pacific and North Atlantic, see Bond et al. 2001, and papers relating to Dr. Gerard Bond’s  work). This original signal then seems to be transmitted across the globe by various climatic phenomena, as several papers on the list point out.

A few papers on the list argue for a solar influence on the Quasi-Biennial Oscillation, which influences monsoon precipitation as well as stratospheric circulation and ozone patterns. In addition, a novel hypothesis proposed originally by Dr. Karin Labitzke argues that the 11-year solar cycle can influence sea level pressure, geopotential heights (associated with pressure levels), and temperature. The solar signal is then modulated by the phase of the QBO, and in turn the QBO is influenced by solar activity.

Several papers on the list argue that solar activity may actually be responsible for at least some of the variability of seemingly internal natural oscillations, such as the AMO, PDO, and ENSO (see below).

Several papers on the list argue for a solar influence on ENSO (El Nino-Southern Oscillation). Moreover, some papers of this group argue that high solar activity actually brings about La Nina (ENSO-negative)-like conditions, and low solar activity brings about El Nino (ENSO-positive)-like conditions.

Many papers on the list argue that solar activity can influence or modulate atmospheric circulation patterns, which are comprised of sea level pressure and geopotential heights and which influence regional and global climate significantly (see above). Some examples of circulation patterns that have been suggested to be influenced by solar activity are the monsoons of various regions around the globe, Intertropical Convergence Zone, Westerlies, Aleutian Low, Icelandic Low, and South Pacific Convergence Zone.

A few papers on this list argue that solar-induced alterations in temperature gradients can significantly influence regional and global climates.

Several papers on the list argue that solar activity variations may be responsible for the Dansgaard-Oeschger and Bond events, two dramatic and rapid climate cycles of the last glacial period (Dansgaard-Oeschger) and Holocene (Bond). (These events were supposed to have a ~1500-year periodicity, but that has been questioned and remains controversial.) This would provide an explanation for multiple strange paleoclimate events of the past and a highly significant amplification mechanism for solar forcing, especially because these events change the climate drastically but quickly and are correlated with other climatic phenomena (Asian monsoon, aridity levels in the Middle East, vegetation in North America, etc.)

There are several papers on the list that argue that solar activity modulation of temperatures on regional scales can affect other climatic variables (e.g., temperature, rainfall, etc.) in that region or other regions.

Several papers on the list argue that solar activity can influence storms of various types, which in turn influence hydroclimate and temperature over short timescales (though the effects can last for a while) in the impacted regions.

Several papers on the list also argue that solar activity either modulates or has a positive feedback from ice (in different locations and forms), which could have implications for other climates around the world.

 

As with all my working lists, it may be incomplete and reasonable new suggestions are welcome. In addition, if anyone has a publicly accessible link to the full paper for those that are paywalled, feel free to show me it. Also, if you think any part of this list is inaccurate and should be changed or removed and have a reasonable argument for why and what I should do with it, feel free to tell me.

 

Just to be fair, I would like to thank PopularTechnology.net and Club du Soleil for their lists of papers on solar forcing of climate, some of which appear here as well.

 

 

Abbreviations

QBO – Quasi-Biennial Oscillation

GCM – General Circulation Model

NADW – North Atlantic Deep Water

AL – Aleutian Low

SST – Sea Surface Temperature

NAO – North Atlantic Oscillation

AO – Arctic Oscillation

GHG – Greenhouse Gas

TSI – Total Solar Irradiance

ENSO – El Nino Southern-Oscillation

NAM – Northern Annular Mode

UV – Ultraviolet

SOI – Southern Oscillation Index

CO2 – Carbon Dioxide

ITCZ – Intertropical Convergence Zone

PDO – Pacific Decadal Oscillation

SPCZ – South Pacific Convergence Zone

AMO – Atlantic Multidecadal Oscillation

LTG – Latudinal Temperature Gradient

MJO – Madden-Julian Oscillation

LIA – Little Ice Age

MWP – Medieval Warm Period

OLR – Outgoing Longwave Radiation

SWW – Southern Hemisphere Westerly Winds

ISM – Indian Summer Monsoon

QDO – Quasi-Decadal Oscillation

ECS – Equilibrium Climate Sensitivity

PNA – Pacific-North American teleconnection

EPTG – Equator-to-Pole Surface Temperature Gradient

AMOC – Atlantic Meridional Overturning Oscillation

SASM – South Asian Summer Monsoon

LOTC – Land-Ocean Thermal Contrast

EASM – East Asian Summer Monsoon

 

Labitzke 1987

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, may influence atmospheric temperatures in the North Pole region, and that this influence is modulated by the phase of the QBO. Studies that build on this connection are discussed later, and add to its significance.

Landscheidt 1988

Why I think it’s important – It argues that several modes of solar variability, including solar X-ray flares, solar rotation, and variations in the Sun’s torque of motion may be related to many climatic phenomena, including atmospheric blocking, ozone, rainfall, iceberg amount, and temperature.

Tinsley 1988

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence North Atlantic storm tracks (when the data are adjusted for the phase of the QBO), corroborating the work of Labitzke and van Loon. In addition, the paper outlines a solar amplification mechanism explaining this process.

Labitzke and van Loon 1988a

Why I think it’ important – It argues that the solar activity, including the Schwabe solar cycle, can influence atmospheric temperatures and geopotential heights (when the data are adjusted for the phase of the QBO) and that the strength of the QBO is influenced by solar activity.

van Loon and Labitzke 1988b

Why I think it’ important – It argues, similar to the authors’ earlier papers, that solar activity, including the Schwabe solar cycle, can influence temperature at different altitudes, geopotential heights, and sea surface pressure (when the data are adjusted for the phase of the QBO).

Labitzke and van Loon 1989

Why I think it’ important – It argues, similar to the authors’ earlier papers, that solar activity, including the Schwabe solar cycle, is correlated with (when the data are adjusted for the phase of the QBO) and can influence atmospheric climatic variables, and that the correlations resemble well-known teleconnections. In addition, it argues that these correlations do not result from chance.

Baliunas and Jastrow 1990

Why I think it’s important – It argues that the Sun’s activity varies more than is assumed by GCMs (one of the main types of climate models used), since they at this point assumed a constant Sun, which would bias their results and make their judgements about solar forcing less reliable.

Peterson et al. 1991

Why I think it’s important – It argues that solar activity can modulate trade wind and upwelling intensity off the coast of Venezuela.

Reid 1991

Why I think it’s important – It argues that solar activity could have been a significant contributor to global climate change in recent decades, and that the Schwabe solar cycle is highly significantly correlated with global SSTs over the past 130 years.

Friis-Christensen and Lassen 1991

Why I think it’s important – It argues that the length of solar cycles can influence Northern Hemisphere climate, as it’s a good indicator of the level of solar activity, and that over the last 130 years, there’s a close correlation between the two. This, say the authors, should be taken into account when trying to assess anthropogenic contribution to recent global warming.

Labitzke and van Loon 1992

Why I think it’s important – It argues that the pattern of correlations between the Schwabe solar cycle and atmospheric temperature and geopotential heights (see the authors’ earlier work) are similar to ozone variability. This result implies that the Schwabe cycle may, to some extent, influence ozone variability, which is consistent with the top-down mechanism.

Anderson 1992

Why I think it’s important – It argues that solar activity can influence surface winds, and that CMEs, events where the Sun emits large amounts of electromagnetic radiation and plasma, influence cyclonic activity and tropospheric winds (more on CMEs in the cosmic ray list).

Charvatova and Strestik 1992

Why I think it’s important – It argues that there is a significant correlation between solar activity and the earth’s global temperature between 1861 and 1990.

Thomas 1993

Why I think it’s important – It argues that solar activity can influence regional rainfall patterns via warming of other parts of the globe and thus influencing storm patterns.

Baliunas and Jastrow 1993

Why I think it’s important – It argues that solar activity could have caused most of the half-degree global warming of the 20th century.

Labitzke and van Loon 1993

Why I think it’s important – It argues that solar activity may influence atmospheric pressure, that solar UV radiation may be the source of a decadal oscillation in the lower stratosphere whose effects penetrate into the troposphere, (in support of the top-down mechanism) and that the temperature change from a given solar cycle is five times large than the irradiance change.

Friis-Christensen 1993

Why I think it’s important – It affirms the conclusions of Friis-Christensen and Lassen 1991, but takes it a step further. The whole globe is correlated with the 11-year solar cycle length, and it’s the best correlation with temperature over the past century, according to the paper.

Hoyt and Schatten 1993

Why I think it’s important – It presents a reconstruction of solar activity that correlates well with global temperatures, so much so that the authors argue that 71% of decadal variance in temperature over the 20th century and ~50% of the variance in the whole three-century record can be explained by solar activity.

Stuiver and Braziunas 1993

Why I think it’s important – It argues that solar activity, by modulating the thermohaline circulation, could be responsible for the cold Maunder Minimum conditions.

Butler 1994

Why I think it’s important – It affirms the conclusions of Friis-Christensen and Lassen 1991, but only for a town in Northern Ireland called Armagh.

Haigh 1994

Why I think it’s important – It summarizes the now widely recognized theory of the top-down solar amplification mechanism. It also argues that the effect of solar variations on climate are not linear.

Hameed and Gong 1994

Why I think it’s important – It affirms the conclusions of Friis-Christensen and Lassen 1991 in China, not only for modern times but also hundreds of years into the past.

Perry 1994

Why I think it’s important – It argues that solar activity, by modulating ocean temperatures, can influence regional precipitation.

Kazantsev 1994

Why I think it’s important – It argues that solar activity (in this case the Schwabe and Bruckner cycles) can modulate permafrost temperature (at least in east Russia), which in turn could melt it, leading to significant consequences for that region and possibly others around the globe.

Lean et al. 1995

Why I think it’s important – It argues that 50% of the Northern Hemisphere warming since 1860 and a third since 1970 can be explained by solar activity.

Labitzke and van Loon 1995

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence atmospheric geopotential heights, temperature, convection, and the Hadley Circulation, and that the QBO modulates the response to the solar cycle, corroborating the author’s earlier results.

Lassen and Friis-Christensen 1995

Why I think it’s important – It affirms the conclusions of Friis-Christensen and Lassen 1991 for a longer time period.

Crowley and Kim 1996

Why I think it’s important – It argues that solar activity is a significant contributor to climate change on decadal-centennial timescales, not just millennial or longer timescales.

van Geel et al. 1996

Why I think it’s important – It argues that an abrupt increase in C14 (Carbon 14) concentrations between 760 and 850 AD, which has been linked to solar activity, coincided with abrupt cooling in many places around the world, as well as with atmospheric and oceanic circulation shifts. This same event also coincided with a Bond event, further lending credence to the idea that these changes were solar-induced (assuming, as Bond et al. 2001 did, that the Bond events were solar-driven).

Haigh 1996

Why I think it’s important – It argues that the 11-year solar cycle can influence wind and storm patterns and the Hadley circulation, as simulated by a GCM, and also that the GCM underestimates the solar signal in the above phenomena as compared to observations.

Karlen and Kuylenstierna 1996

Why I think it’s important – It argues that Scandinavian and North Atlantic paleoclimate records correlate well, and that this can be reconciled by solar influence on NADW, which would then transmit the solar signal to Scandinavia. This result would make further sense because solar activity also correlates well with Scandinavian paleoclimate records used in the paper.

Soon et al. 1996

Why I think it’s important – It argues that solar activity, explaining 71% of the global warming from 1880, is better at explaining it than GHGs.

Butler and Johnston 1996

Why I think it’s important – It affirms the conclusions of Butler 1994, that Armagh temperature is correlated with the length of the solar cycle.

Reid 1997

Why I think it’s important – It argues that solar activity and anthropogenic forcings contributed equally to early 20th century global warming, and the solar contribution to more recent warming may be underestimated.

Christoforou and Hameed 1997

Why I think it’s important – It argues that the 11-year solar cycle can cause large regional climatic anomalies, and that it can influence the AL and Hawaiian High (both are important Pacific pressure systems.)

Willson 1997

Why I think it’s important – It argues that TSI increased during solar cycles 21 and 22, and that this was a large enough increase to cause a significant change in temperature.

White et al. 1997

Why I think it’s important – It argues that there is a clear response of global SSTs to the Schwabe solar cycle, and that solar activity may have played a significant role in 20th century global warming.

Arnold and Robinson 1998

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can, through the top-down mechanism, influence atmospheric circulation, including the Northern Hemisphere winter vortex, and geopotential heights.

Yoshimura 1998

Why I think it’s important – It argues that a natural process involving solar convection could’ve been related to the global warming of the 20th century.

Cliver et al. 1998

Why I think it’s important – It argues that an uncommonly used measure of solar activity, geomagnetic aa index, can explain ~50% of the global warming over since the Maunder Minimum.

Bucha and Bucha 1998

Why I think it’s important – It argues that solar geomagnetic changes can cause large changes in regional atmospheric circulation, amplifying a small solar change into a large effect on regional climate.

Zhou et al. 1998

Why I think it’s important – It affirms the conclusions of Friis-Christensen and Lassen 1991, but this time using tree ring data (since tree rings are climatic variables they can represent a connection between the Sun and climate) for 594 years. In addition, the authors imply that the de Vries/Suess solar cycle exists and can influence climate and climatic variables.

Lean and Rind 1998

Why I think it’s important – It argues that solar activity may have contributed 50% of the Northern Hemisphere warming observed since 1900 and a third since 1970.

Lean and Rind 1999

Why I think it’s important – It argues that solar activity can account for 60% of the global warming since 1650, and 40% of the global warming since 1900.

Shindell et al. 1999

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence ozone levels, and thus surface winds, atmospheric circulation, and pressure levels. In addition, the authors find that regional climate is strongly affected by the Schwabe solar cycle, unlike global climate.

Haigh 1999

Why I think it’s important – It argues that the 11-year solar cycle induces changes in the tropical Hadley cells, causes jets to move poleward, and that using a GCM to simulate such effects may underestimate the actual effects.

van Geel et al. 1999

Why I think it’s important – It argues that the cosmic ray and top-down solar amplification mechanisms could possibly explain how small solar variations produce large climate changes, that the climate system may be much more sensitive to small solar variations than is commonly believed, and that accepting this sensitivity to solar activity may provide explanation to the iceberg variations (Bond events) discussed in Bond et al. 1997 and 2001.

Yu and Ito 1999

Why I think it’s important – It argues that solar activity including 420, 218 (de Vries/Suess), and 143 year cycles can and has influenced northern Great Plains drought frequency, and that because the Greenland ice cores have similarities in their temperature record, solar forcing could’ve produced global-scale climate change through teleconnections created by solar variations.

Chambers et al. 1999

Why I think it’s important – It argues that solar forcing can drive climate on long as well as short (decadal to centennial) timescales. This result has important implications for the attribution of global warming, as the authors note.

Wang et al. 1999

Why I think it’s important – It argues that solar activity, including the Gleissberg solar cycle, can modulate the East Asian monsoon.

Ruzmaikin 1999

Why I think it’s important – It argues that a small solar signal from variations in solar activity, including the 11-year solar cycle, can be significantly amplified by ENSO.

Balachandran et al. 1999

Why I think it’s important – It argues that solar activity can influence the vertical gradients of zonal winds and temperatures, as well as stratospheric and tropospheric circulation.

Bochnicek et al. 1999

Why I think it’s important – It argues that solar activity can modulate the AL and Icelandic Low.

Salby and Callaghan 2000

Why I think it’s important – It argues that solar activity can influence the QBO, and thus other climatic variables, through modulation of equatorial westerlies.

Beer et al. 2000

Why I think it’s important – It argues that there are feedback processes to solar forcing involving clouds, water vapor (which is the most significant GHG, but which has a short lifetime in the atmosphere), ice cover, atmospheric and oceanic heat transport, as well as that solar activity may have contributed about 40% of the global warming in the past 140 years.

Renssen et al. 2000

Why I think it’s important – It argues that solar activity may have triggered the Younger Dryas, and that the solar amplification mechanisms discussed in van Geel et al. 1999 may have helped to bring this about.

Verschuren et al. 2000

Why I think it’s important – It argues that even small variations in solar activity, like those of the Scwhabe solar cycle, can modulate rainfall in equatorial east Africa, and thus, via influence on river inflow, the levels of lakes in that region, such as Lake Naivasha. In addition, it finds strong evidence for the MWP and LIA, and argues that the MWP was drier, and the LIA wetter, than today.

van Loon and Shea 2000

Why I think it’s important – It argues that the 11-year solar cycle is present in atmospheric temperatures and geopotential heights, and that it can influences stratospheric vortices.

Soon et al. 2000

Why I think it’s important – It argues that climate is very sensitive to solar forcing, and provides a mechanism for this observation: solar ultraviolet radiation interacts with clouds and ozone, amplifying the effect from a small one into a large one, in support of the top-down mechanism.

Perry and Hsu 2000

Why I think it’s important – It argues that a simple model of solar activity matches temperatures through the past millennia quite well, and that solar activity may have contributed significantly to recent climate change.

Ogurtsov et al. 2001

Why I think it’s important – It argues that the ~87-year Gleissberg cycle is present significantly in Fennoscandian temperature proxies, but less so in the whole Northern Hemisphere.

Neff et al. 2001

Why I think it’s important – It argues that solar activity, including the Schwabe, Hale, Gleissberg, and de Vries/Suess solar cycles, can affect tropical rainfall, atmospheric and oceanic circulation, and monsoon intensity, all of which are important parts of regional climate.

Reichel et al. 2001

Why I think it’s important – It affirms the conclusions of Friis-Christensen and Lassen 1991, saying there is high significance to the correlation they found.

Udelhofen and Cess 2001

Why I think it’s important – It argues that solar activity, through a top-down influence on atmospheric circulation, can influence cloud cover.

Soukharev and Hood 2001

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can, through the top-down mechanism, modulate the QBO, corroborating the results of Salby and Callaghan 2000.

Hodell et al. 2001

Why I think it’s important – It argues that the 208-year de Vries/Suess solar cycle significantly influenced drought of the past in Peru, and that this solar forcing affected the Maya, who lived there during the period studied.

Bjorck et al. 2001

Why I think it’s important – It argues that climate may be more sensitive to solar variability than previously thought, and that the top-down and cosmic ray solar amplification mechanisms are in place and induce strong positive feedbacks within the climate system to amplify the solar signal. In addition, the event studied in the paper is Bond event 7, and coincided with a reduction in the thermohaline circulation, underpinning the results of Bond et al. 2001.

Bond et al. 2001

Why I think it’s important – It argues that solar activity can modify North Atlantic hydrography, which in turn modulates the production of NADW, with very large impacts on global and North Atlantic climate alike, including influence on the thermohaline circulation, oceanic heat transport, North Atlantic salinity levels, and hydrological and latudinal gradients. The authors also argue that the earth’s climate is highly sensitive to even extremely weak variations in solar activity, that the quasi ~1500-year periodicity seen in North Atlantic ice-rafting levels (more ice-rafting would indicate more ice and decreased temperatures), at least during the Holocene, called Bond events, can be explained by solar activity, more specifically the mechanism(s) described above, and that the top-down mechanism is in place and amplifies even small variations in solar activity. In addition, the authors argue that these Bond events correlate with other climatic anomalies around the globe, including glacial advances in Scandinavia, abrupt cooling in the Netherlands, and strong rainfall in the Indian Ocean monsoon, and with episodes of low solar activity.

Shindell et al. 2001

Why I think it’s important – It argues that even small variations in solar activity can be amplified by the top-down mechanism, which in turn influences the NAO/AO, cloud cover, and ocean circulation, with large effects on climate, especially in the Northern Hemisphere during winter. The authors argue that low Northern Hemisphere winter temperatures during the LIA and warm temperatures during the MWP can be associated with low and high solar activity, respectively.

Kirov and Georgieva 2002

Why I think it’s important – It argues that solar activity can influence the NAO and ENSO through modulation of atmospheric centers of action around the globe.

Agnihotri et al. 2002

Why I think it’s important – It argues that solar activity, including a supposed ~60 year solar cycle, and the Gleissberg and de Vries/Suess solar cycles, can control the Indian and East African monsoons, due to an atmospheric coupling between them. In addition, the authors find evidence for the MWP and LIA, and argue that their results are not inconsistent with those of Verschuren et al. 2000.

Ogurtsov et al. 2002a

Why I think it’s important – It corroborates the findings of Ogurtsov et al. 2001, and also argues for a strong correlation between low clouds and cosmic rays (see cosmic ray list).

Thresher 2002

Why I think it’s important – It argues that solar activity can influence Antarctic zonal west winds, which can in turn modulate southern mid-latitude atmospheric circulation, which affects climate.

Kodera and Kuroda 2002

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can, through the top-down mechanism, influence the westerly and polar night jets, as well as the Brewer-Dobson circulation; hence, as the authors argue, even small variations in solar activity result in large, dynamical, atmospheric changes. By influencing these climatic variables, the solar signal is transmitted downward, from the upper stratosphere to the lower stratosphere.

Viau et al. 2002

Why I think it’s important – It argues that solar activity can force Bond events, and thus produce the quasi ~1500-year periodicity found in paleoclimate records worldwide. Solar variability, argues the authors, induces reoganizations of atmospheric circulation and the ocean-atmosphere system. In this way, the solar signal is transmitted around the globe, corroborating the results of Bond et al. 2001.

Ogurtsov et al. 2002b

Why I think it’s important – It argues that the Gleissberg and de Vries/Suess solar cycles are present in a multiproxy Northern Hemisphere temperature reconstruction.

Kodera 2002

Why I think it’s important – It argues that solar activity (the signal of which might originate from the upper stratosphere and penetrate downward) can modulate the NAO.

Douglass and Clader 2002

Why I think it’s important – It argues that solar activity has positive feedbacks and that earth’s sensitivity to solar irradiance changes is twice that which would be commonly expected, but consistent with the results of White et al. 1997 and Lean and Rind 1998. Because of this, the authors argue that solar activity is responsible for between 31 and 36% of the recent global warming.

Burns et al. 2002

Why I think it’s important – It argues that solar activity, including the Schwabe, Hale, Gleissberg, and de Vries/Suess solar cycles, can influence Indian Ocean monsoon rainfall. In addition, it finds that recent monsoon variations are within the range of natural variability.

Ruzmaikin and Feynman 2002

Why I think it’s important – It argues that solar activity,  can modulate the NAM, an important component of atmospheric circulation which is also another name for the NAO/AO, but that the influence of solar activity on the NAM depends on the phase of the QBO, corroborating the work of Labitzke and van Loon.

Kristjansson et al. 2002

Why I think it’s important – It argues that solar UV radiation can influence planetary waves and thus atmospheric circulation and climate, and also low cloud cover.

Gimeno et al. 2003

Why I think it’s important – It supports the findings of Kodera 2002, and argues that solar activity can influence the NAO, since the relationship between the NAO and Northern Hemisphere temperature is different depending on solar activity.

Meehl et al. 2003

Why I think it’s important – It argues that volcanic and solar activity, and thus natural variability, were the dominant cause of early 20th century warming, and that solar activity can influence evaporation levels, monsoons, including the West African and South Asian monsoons, the Hadley and Walker circulations, cloud cover, and meridional temperature gradients.

Tourpali et al. 2003

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can, through the top-down mechanism, influence zonal winds, geopotential heights and sea level pressure and thus atmospheric circulation, including the NAO. In addition, the authors find that regional climate is strongly affected by the Schwabe solar cycle, unlike global climate.

Willson and Mordvinov 2003

Why I think it’s important – It argues that solar activity significantly increased during the solar cycles 21 to 23 (from 1978 to 2002), and that this has implications for climate change.

Gleisner and Thejll 2003

Why I think it’s important – It argues that there are statistically significant, consistent solar signals in tropospheric data when other variables are removed, and that solar activity can modulate global-scale tropospheric circulation, including the Ferrel, Hadley, and Walker circulations. In addition, the authors find that their results are related to those of Labitzke and van Loon 1995.

Hu et al. 2003

Why I think it’s important – It argues that even small variations in solar activity, like those of the de Vries/Suess solar cycle, can have significant effects on Northern Hemisphere high-latitude ecosystems and climate through amplification by the NAO/AO or NADW, and that its paleoclimate record for high-latitudes and Bond et al. 2001’s record for the North Atlantic correspond well, corroborating the notion of a common solar forcing of climate.

Fleitmann et al. 2003

Why I think it’s important – It argues that solar activity, including the Schwabe, Gleissberg, and de Vries/Suess solar cycles, can influence the Indian monsoon both directly and indirectly, by inducing Bond events, which in turn modulate Eurasian snow cover and thus the Indian monsoon.

Stott et al. 2003

Why I think it’s important – It argues that models underestimate the climate sensitivity to solar activity, the solar contribution to 20th century global warming, and that solar activity was more important than GHGs in early 20th century warming.

Scafetta and West 2003

Why I think it’s important – It argues that solar flare activity can influence earth’s short-term global temperature anomalies.

Usoskin et al. 2003

Why I think it’s important – It argues that solar activity since the 1940s has been unusual in the context of the past 1,150 years. The authors remark that this reconstruction of solar activity correlates well with temperature reconstructions over the same time period.

van de Plassche et al. 2003

Why I think it’s important – It argues that solar activity, with a lag of about 125 years, can modulate northwest Atlantic sea level by influencing deep-ocean salinity levels through the North Atlantic overturning circulation.

Poore et al. 2003

Why I think it’s important – It argues that solar activity, including ~150 and ~300-year solar cycles and the de Vries/Suess solar cycle, and a ~300-year solar cycle, can influence the ITCZ and thus Caribbean-Gulf of Mexico climate. In addition, the authors find evidence for the MWP and LIA.

Haigh 2003

Why I think it’s important – It argues that there may be chemical and dynamical feedbacks to solar activity which amplify the signal, that solar signals can be differentiated from other modes of natural variability, that the solar signals on climate can be detected on decadal, centennial, and millennial timescales, and that GCMs may underestimate the magnitude of the solar effect on climate.

Kodera 2003

Why I think it’s important – It argues that solar activity can influence the NAO, which significantly affect climate in the North Atlantic and surrounding regions.

Palamara and Bryant 2004

Why I think it’s important – It argues that solar-modulated geomagnetic activity can influence atmospheric circulation, specifically the NAM.

Solanki et al. 2004

Why I think it’s important – It argues that solar activity during the past 70 years is exceptional in the past 11,000 years, and that this implies that solar activity was a contributor to recent climate change.

Matthes et al. 2004

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence tropospheric circulation, the polar night jet, and mean meridional circulation. In addition, it finds that the QBO can modulate the solar signal, corroborating the work of Labitzke and van Loon.

Scafetta et al. 2004

Why I think it’s important – It argues that solar flare activity can influence earth’s short-term global temperature anomalies, and that solar flare activity and TSI are related, as well as that solar activity may influence atmospheric water vapor content. These results corroborate those of Scafetta and West 2003.

Kodera 2004

Why I think it’s important – It argues that solar activity can influence atmospheric circulation, including the Brewer-Dobson circulation, convective activity, the jet stream, upwelling, and thus the Indian Ocean monsoon, corroborating the results of Neff et al. 2001, Burns et al. 2002, Fleitmann et al. 2003, and the work of Labitzke and van Loon.

Coughlin and Tung 2004

Why I think it’s important – It argues that a significant response to the Schwabe solar cycle is present in earth’s climate-in atmospheric temperatures and geopotential heights.

Poore et al. 2004

Why I think it’s important – It argues that solar activity, including ~150 and 300-year solar cycles and the de Vries/Suess solar cycle, can influence the ITCZ and thus Caribbean-Gulf of Mexico climate variability. In addition, the authors find close correspondence between their paleoclimate record and the paleoclimate record of Bond et al. 2001, and evidence for the MWP and LIA.

van Loon et al. 2004

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence the Hadley and Walker circulations, precipitation and ozone levels, vertical motion, OLR, and cloud properties, to produce a decadal oscillation in the tropics.

Weber et al. 2004

Why I think it’s important – It argues that solar activity can influence temperature, monsoon precipitation, and glacier length, and also that the thermohaline circulation (a highly important component of oceanic circulation) can be influenced by solar variability.

Raspopov et al. 2004a

Why I think it’s important – It argues that northern high-latitude climate records reflect the Gleissberg, Hale, and Schwabe solar cycles and that solar activity has a nonlinear influence on the atmosphere-ocean-continental system.

Raspopov et al. 2004b

Why I think it’s important – It argues that the 22-year solar cycle produced a similarly timed temperature response in the Russian Arctic Ocean coast, and that this weak solar signal is amplified significantly by the atmosphere and ocean, some processes of whom also have a 22-23 year periodicity.

Higginson et al. 2004

Why I think it’s important – It argues that throughout the past, Dansgaard-Oeschger events, tropical monsoon variability, the SOI (and thus ENSO, for the SOI is the measure of ENSO variability), and Eurasian winter snow cover are linked, and through solar modulation of monsoon rainfall, ENSO, and Dansgaard-Oeschger event timing, the Sun could play a role in climatic variability (including the above climatic variables) all around the globe.

Ruzmaikin et al. 2004

Why I think it’s important – It argues that solar activity, through the top-down mechanism, can modulate the NAM.

Labitzke 2004

Why I think it’s important – It argues that the Schwabe cycle influences mean meridional circulation systems (Hadley and Brewer-Dobson), and that the 11-year solar cycle is correlated with geopotential heights and temperatures at different pressure levels when they are adjusted for QBO phase.

Lund and Curry 2004

Why I think it’s important – It argues that solar activity can influence the NAO and Florida Straits temperature.

Patterson et al. 2004

Why I think it’s important – It argues that cosmic rays and solar activity, including the de Vries/Suess solar cycle, can influence the AL, PDO, and NPH.

Kodera and Kuroda 2005

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence the NAO and zonal mean winds.

Jiang et al. 2005

Why I think it’s important – It argues that solar activity is an important part of natural climate variability, and that solar variability can influence wind patterns and the East Icelandic Current.

Baldwin and Dunkerton 2005

Why I think it’s important – It argues that solar forcing can be amplified through interaction with Rossby waves and through stratosphere-near surface circulation coupling.

Stager et al. 2005

Why I think it’s important – It argues that solar activity, through links with tropical temperature and rainfall, can modulate the level of Lake Victoria.

Dykoski et al. 2005

Why I think it’s important – It argues that solar activity, including the Schwabe, Gleissberg, and de Vries solar cycles, can modulate the Indian monsoon.

Bhattacharyya and Narasimha 2005

Why I think it’s important – It argues that there is a robust connection between solar activity and Indian monsoon rainfall, and that their results are not inconsistent with those of Haigh et al. 2005.

Prasad et al. 2005

Why I think it’s important – It argues that solar activity, by influencing North Atlantic climate and transmitting the solar signal through influence on North Atlantic cyclonic activity and/or the NAO, can also influence Mediterranean temperature and hydroclimate. In addition, it argues that there must be a solar amplification mechanism in place, and that Mediterranean climate reflects a 50-60 year natural climate cycle, Bond events, a 1500-year cycle that was linked to solar activity in Bond et al. 2001 and Braun et al. 2005 and 2008, and the Gleissberg and de Vries/Suess solar cycles.

Tourpali et al. 2005

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can, through the top-down mechanism, affect tropospheric circulation, including the NAO/AO.

Haigh et al. 2005

Why I think it’s important – It argues that stratospheric temperature anomalies (like those produced by solar activity) can influence atmospheric circulation, such as the subtropical jets, the mean meridional circulation, the tropical Hadley cells, and the Ferrel cells.

Willard et al. 2005

Why I think it’s important – It argues that solar activity, by inducing variations in the circumpolar vortex, jet stream, and meridional circulation, can force Bond events, and thus explain the quasi ~1500-year periodicity found in paleoclimate records worldwide.

Wang et al. 2005

Why I think it’s important – It argues that solar activity, including ~150 and ~512-year solar cycles and the Gleissberg and de Vries/Suess solar cycles, can modulate the Asian monsoon, and that the North Atlantic and Asian Monsoon climates share correlations that could be explained by a common solar forcing, corroborating the results of Neff et al. and Bond et al. 2001, and Fleitmann et al. 2003.

Weng 2005

Why I think it’s important – It argues that small solar activity changes can result in large changes in regional climate, and that interannual-centennial variability in regional climate is not purely internal, but also possibly driven by solar activity. This, as the author acknowledges, has implications for research on climate change.

Lucio 2005

Why I think it’s important – It argues that solar activity can influence Portuguese rainfall, that as a consequence solar activity might be used as a rainfall predictor, and that Portuguese climate might be more sensitive to solar variations than is commonly believed.

Braun et al. 2005

Why I think it’s important – It argues that the Dansgaard-Oeschger events (that have a periodicity of ~1470 years) may be driven by solar activity, even though there does not appear to be a ~1470-year solar cycle.

Mayewski et al. 2005

Why I think it’s important – It argues that solar activity, through the top-down mechanism, can affect atmospheric circulation at both poles, including zonal winds and polar vortexes.

Bochnicek and Hejda 2005

Why I think it’s important – It argues that solar activity (as well as geomagnetic activity, through the global electric circuit, see cosmic ray list) can influence the NAO.

Dyoski et al. 2005

Why I think it’s important – It argues that solar activity, including the Gleissberg and de Vries/Suess solar cycles,

Muller et al. 2005

Why I think it’s important – It argues that solar activity may have triggered Eemian climate variability, possibly through amplification by the NAO and/or North Atlantic ocean currents.

Larsen 2005

Why I think it’s important – It argues that solar UV and blue light variations can, through a system of positive feedbacks, modulate cloud cover, SSTs, and climate.

Scafetta and West 2005

Why I think it’s important – It argues that solar activity increased between 1980 and 2002, and that this could have contributed to the global warming over that period.

Lim et al. 2005

Why I think it’s important – It argues that solar activity can modulate Asian dust through influence on the East Asian monsoon.

Soon 2005

Why I think it’s important – It argues that solar activity explains more than 75% of decadally-smoothed Arctic air temperature variance, that solar variability can influence Arctic atmospheric circulation and sea ice patterns, and that a CO2-dominated Arctic climate is inconsistent with observations.

Hameed and Lee 2005

Why I think it’s important – It argues that solar modulation of stratospheric circulation is translated down through the troposphere to the earth, and the earth’s climate, providing a solar amplification mechanism.

Gupta et al. 2005

Why I think it’s important – It argues that small changes in solar activity can have very large effects on tropical monsoons, and that it has for thousands of years in the past as well.

Alexeev and Ustinova 2006

Why I think it’s important – It argues that a recent increase in a 600-year solar cycle is one of the major causes of recent global warming.

Scafetta and West 2006a

Why I think it’s important – It argues that solar activity could be responsible for up to 50% of the 20th century global warming, and 35% of the temperature rise between 1980 and 2000.

Matthes et al. 2006

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, through the top-down mechanism, can influence the polar night jet, Brewer-Dobson circulation, stratospheric and tropospheric circulation, zonal winds, planetary waves, mean meridional circulation, surface pressure, temperature, and produce AO-like conditions, corroborating the results of Kodera and Kuroda 2002. By influencing these climatic variables, the solar signal is transmitted downard, from the upper stratosphere, to the lower stratosphere, to the troposphere, to the surface.

Lamy et al. 2006

Why I think it’s important – It argues that solar activity can force large-scale atmopspheric circulation changes, and influence the NAO/AO.

Lim et al. 2006

Why I think it’s important – It argues that even small variations in solar activity can produce, or at least modulate, the tropical Atlantic oscillation through influence on humidity levels.

Yousef 2006

Why I think it’s important – It argues that solar activity can force abrupt changes in the NAO, lake levels, and droughts.

Lund and Curry 2006

Why I think it’s important – It argues that even modest variations in solar activity can bring about large changes in the ITCZ and Florida Current salinity levels.

Polissar et al. 2006

Why I think it’s important – It argues that solar activity can and has modulated tropical temperature and rainfall through, that the solar signal in high latitudes is enhanced by water vapor feedbacks, and that tropical climate is very sensitive to solar activity changes.

Usoskin et al. 2006

Why I think it’s important – Its conclusions are similar to those of Usoskin et al. 2003 and Solanki et al. 2004: that solar activity at the end of the 20th century is very unusual in the past 7000 years.

Scafetta and West 2006b

Why I think it’s important – It argues that solar activity could have contributed up to 50% of the observed Northern Hemisphere warming since 1900.

Labitzke et al. 2006

Why I think it’s important – It argues that solar activity, including the Schwabe cycle, can significantly influence the stratospheric polar vortex and mean meridional circulation.

Perry 2006

Why I think it’s important – It argues that solar activity, through a complex, six-step mechanism (by which many other processes than streamflow are influenced) can influence regional streamflow (the flow of a river, stream, etc.)

Huth et al. 2006

Why I think it’s important – It argues that solar activity can significantly influence atmospheric circulation in various ways (strength, location, extent, etc.)

Hormes et al. 2006

Why I think it’s important – It argues that solar activity can and has modulated glacier extent and properties, and that it may have far more influence on them than has been assumed in the past.

Rigozo et al. 2006

Why I think it’s important – It argues that tree ring growth records show the ~87-year Gleissberg and ~208-year de Vries/Suess solar cycles, and that this represents a connection between solar activity and terrestrial climate.

Salby and Callaghan 2006

Why I think it’s important – It argues that the solar cycle can significantly influence a decadal oscillation in the tropical troposphere, which can modulate temperature.

Ruzmaikin et al. 2006

Why I think it’s important – It argues that a solar amplification involving solar influence on the NAM can influence the Atlantic and Indian Ocean patterns and thus Nile water level.

Shindell et al. 2006

Why I think it’s important – It argues that solar activity can influence tropical hydrology by modulating temperatures and ozone concentrations, and that this has happened in the past with consequences for civilization.

Hammel and Lockwood 2007

Why I think it’s important – It argues that solar variability that is affecting other planets may also be affecting this one, and possibly causing the global warming we’re seeing, as there has been a correlation between Neptune’s brightness and our temperatures.

Kodera et al. 2007

Why I think it’s important – It argues that solar activity, by modulating Indian monsoon circulation which then influences the Walker circulation, can modify the connection between the Indian and Pacific Oceans’ climate.

Asmerom et al. 2007

Why I think it’s important – It argues that solar activity can modulate southwestern United States rainfall by influencing the Walker circulation, PDO, and ENSO.

Vovk and Egorova 2007

Why I think it’s important – It argues that various indices of solar activity (sunspots, solar flares, auroral electrojet magnetic levels, and the interplanetary magnetic field) can influence ENSO.

Scafetta and West 2007

Why I think it’s important – It argues that solar activity could’ve contributed 50% of the Northern Hemisphere warming since 1900, or perhaps even more.

Mazzarella 2007

Why I think it’s important – It argues that solar activity, through a complex series of solar amplification mechanisms, can be tied to the recent global warming as well as more short-term trends.

Kryjov and Park 2007

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can modulate the ENSO-NAM connection.

Emile-Geay et al. 2007

Why I think it’s important – It argues that even modest variations in solar activity can significantly modulate ENSO, with ENSO acting as a mediator between the Sun and global climate. The authors argue that the solar influence begins by increased solar activity forcing ENSO-negative conditions in the Pacific (corroborating the work, among others, of van Loon et al. 2007), which in turn weakens the Indian and Asian monsoons, and triggering Bond events, with possibly other feedbacks from atmospheric and oceanic circulation, including the thermohaline circulation, and clouds.

Stager et al. 2007

Why I think it’s important – It argues that even small variations in solar activity, like those of the Schwabe solar cycle, can be amplified through interactions with ENSO, SSTs, and atmospheric circulation to significantly influence rainfall patterns over Lake Victoria and other lakes of East Africa. These results underpin the findings of Stager et al. 2005.

Ivanov 2007

Why I think it’s important – It argues that solar activity, including the 11-year solar cycle, can modulate tropical cyclones around the globe, and that this happened during Solar Cycle 23.

Thamban et al. 2007

Why I think it’s important – It argues that the Indian monsoon has periodicities matching many known solar cycles, and that small solar activity variations can and have controlled the Indian monsoon to a large extent.

Kaspari et al. 2007

Why I think it’s important – It argues that solar activity can force large changes in hemispheric and monsoonal circulation.

Georgieva et al. 2007

Why I think it’s important – It argues that solar activity can influence global atmospheric circulation, including effects on the NAO and NAM.

Goode and Palle 2007

Why I think it’s important – It argues that there is a significant solar amplification mechanism by which solar activity can influence the earth’s albedo and modulate the global climate.

Huth et al. 2007

Why I think it’s important – It argues that solar activity can modulate the AO.

van Loon et al. 2007

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence northwestern United States precipitation through adjusting tropical Pacific climate conditions, including the ITCZ and SPCZ, which then modify precipitation and trade winds of that region, which in turn modulate upwelling of the eastern equatorial Pacific which then reduces precipitation in the western Pacific. This chain of events then modifies the Hadley and Walker circulations, which in turn produce a Rossby wave which modulates sea surface pressure anomalies in the AL, which finally influence northwestern United States precipitation. Moreover, the authors argues that Schwabe cycle peaks can produce ENSO-negative-like conditions in the Pacific (which then transmit their signal via teleconnection).

Versteegh et al. 2007

Why I think it’s important – It argues that solar activity can influence wind-induced mixing in the Mediterranean Sea, and thus biological productivity and SSTs.

Camp and Tung 2007

Why I think it’s important – It argues that solar cycle variations contributed significantly to the global warming since 1959, amounting to a 0.2 degrees Celsius contribution.

Ferguson and Veizer 2007

Why I think it’s important – It argues that solar activity, by influencing the water cycle, can drive the carbon cycle, which would necessarily impact climate, since CO2 is a GHG.

Brauer et al. 2008

Why I think it’s important – It argues that solar activity, including the Gleissberg and de Vries/Suess solar cycles, can modulate Alpine climate.

White and Liu 2008a

Why I think it’s important – It argues that solar activity, including the 11-year Schwabe cycle, can influence the QDO, a pattern of sea surface pressure and SSTs in the Pacific.

Velasco and Mendoza 2008

Why I think it’s important – It argues that solar activity can influence large-scale atmospheric phenomena, including the NAO, AMO, PDO and/or ENSO.

Shaviv 2008

Why I think it’s important – It argues that earth’s climate response to the solar cycle is 5 to 7 times larger than would be expected from only considering TSI variations, and that there is probably a solar amplification mechanism in place to intensify the solar effect.

Braun et al. 2008

Why I think it’s important – It affirms the conclusions of Braun et al. 2005: that activity is responsible for the important natural ~1470-year climate cycle.

Le Mouel et al. 2008

Why I think it’s important – It argues that there is a significant solar signal in 20th century temperature records for Europe and the United States, and that this probably applies for global 20th century temperature records as well.

West and Grigolini 2008

Why I think it’s important – It affirms the conclusions of Scafetta and West 2003 and argues that the correlation between solar flares and Earth’s short-term temperature anomalies is not accidental.

Barriopedro et al. 2008

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can modulate Northern Hemisphere blocking, and that this solar influence on blocking may have contributed to cold conditions during the Maunder Minimum.

White and Liu 2008b

Why I think it’s important – It argues that solar activity can influence ENSO through modification of the QDO, which then drives or synchronizes ~3.6 and ~2.2 year ENSO periodicities.

van Loon and Meehl 2008

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence sea level pressure, trade and stratospheric winds, upwelling, SSTs, the Walker Circulation, and the strength of the QBO. It also argues that the Pacific is sensitive to solar forcing (at least in northern winter), and that their results corroborate those of van Loon et al. 2007.

Baker 2008

Why I think it’s important – It argues that solar activity can influence Southern Hemisphere rainfall patterns through various solar cycle modulations of the SOI (and thus ENSO).

Zanchettin et al. 2008

Why I think it’s important – It argues that solar activity, by modulating the NAO, can influence regional hydroclimate.

Vieira et al. 2008

Why I think it’s important – It finds a link between tropical Pacific sea level pressure and Earth’s geomagnetic activity, and argues that this supports a direct link between solar activity and climate.

Raspopov et al. 2008

Why I think it’s important – It argues that the de Vries/Suess solar cycle is present in paleoclimate proxies and can influence temperature, precipitation, and atmospheric and oceanic circulation.

Mauas et al. 2008

Why I think it’s important – It argues that solar activity correlates well with and can influence regional hydroclimate, in this case streamflow of the Parana river in South America. In addition, it argues that solar activity can be used as a flood predictor for this reason.

Springer et al. 2008

Why I think it’s important – It argues that solar activity, including the ~200-year solar cycle, can modulate east-central North American droughts, as well as mid-continent climates. The record of droughts also correlate well, in some cases, with the Bond events, which were linked to solar forcing in Bond et al. 2001 and other papers.

Huth et al. 2008

Why I think it’s important – It argues that solar impact on climate is nonlinear and that it a mechanism for this connection is a solar influence on atmospheric circulation and cyclonic activity.

Mendoza and Velasco 2009

Why I think it’s important – It argues that solar variability can influence some important biological parameters, including one which could influence cloud formation.

Kurian et al. 2009

Why I think it’s important – It argues that solar activity can affect coastal upwelling and biological productivity.

Scafetta and Willson 2009

Why I think it’s important – It argues that datasets measuring solar activity did show an increase between 1980 and 2000, and that this could’ve contributed significantly to the global warming over that period.

Le Mouel et al. 2009

Why I think it’s important – It argues that there are significant solar imprints in 20th century European pressure and temperature records, and that solar activity can significantly drive atmospheric variations in Europe.

Johnson 2009

Why I think it’s important – It argues that the 22-year Hale cycle of solar magnetic activity may be present in the Central England Temperature record.

Eichler et al. 2009

Why I think it’s important – It argues solar activity, including the Gleissberg and de Vries/Suess solar cycles, can influence oceanic and atmospheric circulation, including the NAO/AO, and thus temperature in the remote Altai region of Russia, corroborating the findings of Shindell et al. 2001 and Perry 2007. In addition, the authors agree with Scafetta and West 2007 that only up to 50% of the global warming in the past 100 years can be attributed to solar activity.

Wasko and Sharma 2009

Why I think it’s important – It argues that solar activity (in this case the 11-year solar cycle) can modulate atmospheric moisture content and thus reduce moisture availability variations.

Scafetta 2009

Why I think it’s important – It argues that TSI variations alone used in a model can reproduce temperature changes over the past 400 years, and that if the ACRIM TSI dataset is used, 65% of the global warming we’ve experienced could’ve been due to solar activity.

Meehl and Arblaster 2009

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can produce both ENSO-negative (at the Schwabe solar cycle peak) and ENSO-positive (a few years after the peak) conditions in the Pacific, corroborating the findings of, among others, White et al. 1997, van Loon et al. 2007, and White and Liu 2008a.

Soon 2009

Why I think it’s important – It affirms the conclusions of Soon 2005 and provides evidence that is in support of conclusions favoring significant impacts of solar activity variations on Arctic climate.

Zhao et al. 2009

Why I think it’s important – It argues that solar activity, including the ~200-year de Vries/Suess solar cycle, can modulate moisture levels in the northeast Tibetan Plateau by influencing Chinese monsoon intensity.

Meehl et al. 2009

Why I think it’s important – It argues that two solar amplification mechanisms, the top-down and bottom-up mechanisms, are in place and work together, modulating precipitation, temperature, and cloud cover, and amplifying the solar signal to the surface.

Mendoza and Pazos 2009

Why I think it’s important – It argues that solar activity (and possibly cosmic rays), including the Hale solar cycle, can influence tropical cyclone activity.

Dergachev and Raspopov 2009

Why I think it’s important – It argues that the Gleissberg and de Vries/Suess solar cycles could’ve produced a global warming that resembles that seen over the 20th century.

Courtillot et al. 2010

Why I think it’s important – It argues that solar activity and temperature in the US North Pacific are closely related, that the temperature response is very large compared to the corresponding solar variability, and that the solar amplification mechanism responsible for this may be solar influence on the MJO or cloud cover.

Ogurtsov et al. 2010

Why I think it’s important – It argues that even weak solar variations could produce a large climatic reponse if the climate system is nonlinear, which it is.

Marchitto et al. 2010

Why I think it’s important – It argues that solar activity can infleunce and even control ENSO.

Helama et al. 2010

Why I think it’s important – It argues for the existence of sub-Milankovitch solar cycles of bimillennial and millennial origins, and also that the millennial cycle, if amplified by internal climate processes like ENSO and the thermohaline circulation, could provide explanation for the MWP and LIA.

Zhou and Tung 2010

Why I think it’s important – It argues that a significant response of global SSTs and climate to the Schwabe cycle is detectable, and that solar activity contributed somewhere less than 25% of the SST warming over the past 150 years.

Swingedouw et al. 2010

Why I think it’s important – It argues that solar activity can modulate the NAO and the thermohaline circulation, the latter having large implications for global climate.

Woolings et al. 2010

Why I think it’s important – It argues that a geomagnetic indicator of solar activity correlates better than TSI with regional atmospheric circulation, that sometimes anomalies induced by solar activity changes resemble the NAO, and that solar activity can influence atmospheric circulation patterns around the world.

Lockwood et al. 2010a

Why I think it’s important – It argues that solar activity can influence European atmospheric blocking and circulation, and that as a consequence low solar activity can cause cold winters in the United Kingdom.

Lockwood et al. 2010b

Why I think it’s important – It argues that the top-down mechanism may be more important in tropospheric variations than previously believed, that it provides explanation for many paleoclimatic phenomena, that climate models should include it in their processes, and that their results are not inconsistent with an influence of solar activity on the NAO. The observations of Bond et al. 2001, they argue, could be reconciled with a top-down influence on North Atlantic and European climate.

Czymzik et al. 2010

Why I think it’s important – It argues that solar activity can influence floods in southern Germany through a link with midlatitude atmospheric circulation patterns.

Morner 2010

Why I think it’s important – It argues that solar activity can influence the Earth’s rate of rotation, which, by changing extent of Arctic water and ocean surface currents, can strongly influence regional climate.

de Jager et al. 2010

Why I think it’s important – It argues that solar activity significantly influenced the temperature gradient from 1610 to 1970 and that there are significant feedbacks and amplifiers to solar variations.

Sejrup et al. 2010

Why I think it’s important – It argues that solar activity can induce 1-2 degree Celsius variations in Norwegian Sea temperature, which is larger than expected. It also argues that the Sun accomplishes this by modulating regional atmospheric variability, which in turn influences oceanic heat transport and SSTs.

Prestes et al. 2011

Why I think it’s important – It argues that tree rings reflect the 11, 22, and 80-year solar cycles.

Soon et al. 2011

Why I think it’s important – It argues that solar activity caused a significant multidecadal variation in China’s 20th century temperature, and that it also provides climatic teleconnections via the solar irradiance-Arctic–North Atlantic overturning circulation mechanism discussed in Soon 2009.

Shapiro et al. 2011

Why I think it’s important – It argues that a new approach to reconstructing historical solar activity gives a very large forcing from solar variations, that reconstructed solar UV variability is larger than previous estimates, that the Maunder Minimum’s solar activity was much lower than today’s, that the reconstructed change in solar activity from Maunder Minimum to today is much larger than other estimates, and that there was a large increase in solar forcing during the first half of the twentieth century.

Davis and Brewer 2011

Why I think it’s important – It argues that solar, lunar, and orbital activity control the earth’s LTG, which drives the earth’s oceanic and atmospheric circulation, and thus impacts the climate enormously.

Laken et al. 2011

Why I think it’s important – It argues that solar activity, including irradiance, changes can influence cloud cover, which would in turn influence climate.

Mauas et al. 2011

Why I think it’s important – It affirms and extends the conclusions of Mauas et al. 2008, arguing that solar activity can modulate streamflow in other rivers of South and North America as well, and that this relationship may have taken place significantly during the LIA.

Ineson et al. 2011

Why I think it’s important – It argues that solar activity can produce temperature and pressure patterns resembling the NAO/AO, that the top-down solar amplification mechanism may be confirmed by their results, and that solar activity may be driving recent cold Northern Hemisphere winters.

Lu and Jarvis 2011

Why I think it’s important – It argues that solar activity can influence the QBO.

Hong et al. 2011

Why I think it’s important – It argues that solar activity can influence OLR (which is how heat escapes to space, so it has obvious climatic implications) and cause rapid changes in SSTs, called the oceanic dipole.

Bal et al. 2011

Why I think it’s important – It argues that solar activity (in this case the Schwabe cycle) can produce conditions resembling different phases of ENSO in the tropical Pacific, corroborating the findings of Meehl et al. 2009.

Hong et al. 2011

Why I think it’s important – It argues that solar activity can produce ENSO-positive-like conditions in the Pacific, which in turn produces a teleconnection between the Northern Hemisphere and Asian monsoon, through which those Pacific anomalies cause abrupt variations in the Asian monsoon. In this way the solar signal is transmitted around the globe.

Santos et al. 2011

Why I think it’s important – It argues that solar activity, including the 11 and 87-year solar cycles, can influence oceanic upwelling.

Varma et al. 2011

Why I think it’s important – It argues that solar activity can influence the SWW (an important atmospheric circulation mechanism which influences precipitation, oceanic circulation, and CO2 budgets), and that this has happened in the past.

Agnihotri et al. 2011

Why I think it’s important – It argues that TSI is a significant forcing on ISM rainfall and that dry periods in the past coincide (and may be influenced by) with low TSI levels.

Tan et al. 2011

Why I think it’s important – It argues that solar activity was the dominant driver of precipitation and temperature (when they were in sync) in north central China over the past 1800 years.

Wang and Zhang 2011

Why I think it’s important – It argues that solar activity has modulated climate and tree growth in Tibet by variations in its radiative output and by its influence on monsoonal precipitation in that region.

Hamanaka et al. 2012

Why I think it’s important – It argues that solar activity can influence coral reef growth by inducing global climate changes.

Rampelotto et al. 2012

Why I think it’s important – It argues that the Schwabe and Hale cycles both affect Brazilian rainfall and temperature, and that the Hale cycle is possibly more important than the Schwabe cycle for climate.

Nichols and Huang 2012

Why I think it’s important – It argues that small solar variations can by amplified by the NAO/AO, producing observed historical hydrological variations in the northeastern United States.

Labitzke and Kunze 2012

Why I think it’s important – It argues that the Schwabe cycle (when QBO phase is accounted for) influences lower and middle stratospheric temperatures and geopotential heights, as well as the equatorial QBO.

Blanter et al. 2012

Why I think it’s important – It argues that solar activity, including UV variability and the 11-year solar cycle, can robustly influence the MJO.

Leal-Silva and Velasco Herrera 2012

Why I think it’s important – It argues that solar activity, including the Schwabe cycle, can and has influenced Baltic sea ice severity levels.

Ziskin and Shaviv 2012

Why I think it’s important – It argues that solar activity contributed about 40% to the recent climate change and that the solar impact on climate is much larger than that which would be expected from TSI variations alone.

van Loon et al. 2012

Why I think it’s important – It argues that solar activity may influence the NAO and North Atlantic sea level pressure, and that this may result as a consequence of differing temperature gradients between different levels of solar activity.

Mazzarella and Scafetta 2012

Why I think it’s important – It argues that solar activity can influence a 60-year oscillation that is related to the NAO and correlates well with SST records since 1850.

Misios and Schmidt 2012

Why I think it’s important – It argues that solar activity, including the 11-year solar cycle, can cause the tropical Pacific temperature to rise and fall, and influence convection, easterlies, and water vapor feedbacks.

van Loon and Meehl 2012

Why I think it’s important – It argues that solar activity can influence ISM precipitation patterns, sea level pressure patterns, and the Findlater Jet.

Varma et al. 2012

Why I think it’s important – It argues that solar-induced stratospheric ozone variations have an influence on tropospheric dynamics, the SWW, and that this solar influence on the SWW was present during the Maunder Minimum.

Martin-Puertas et al. 2012

Why I think it’s important – It argues that solar-induced atmospheric circulation changes caused rapid climate changes in the past.

Schmidt et al. 2012

Why I think it’s important – It argues solar activity can be a significant contributor to variations in the global tropical hydrological cycle. It also argues that solar activity can modulate salinity of the Florida straits, as well as force dramatic reorganizations of atmospheric circulation, permanent ENSO-positive-like conditions in the tropical Pacific. Finally, weakening of the Asian monsoon, and Bond events, all of which are correlated with each other, corroborating the work of van Loon et al. 2007 and Emile-Geay et al. 2007.

Solheim et al. 2012

Why I think it’s important – It argues that solar activity could explain ≥40% of the European warming in the past 150 years, that Solar Cycle 24 will bring cooler temperatures, and that Atlantic currents amplify solar signals to surrounding regional climates.

Sirocko et al. 2012

Why I think it’s important – It argues that solar activity, through influence on atmospheric circulation patterns and temperature anomalies, can modulate winter and ice severity in central Europe.

Ersek et al. 2012

Why I think it’s important – It argues that solar activity, by influencing tropical Pacific climatic conditions, which are then transmitted around the globe, could’ve modulated extreme wet and dry events of Western North America by influencing storm paths.

Seidenglanz et al. 2012

Why I think it’s important – It argues that the Gleissberg and de Vries/Suess solar cycles both have oceanic climatic amplifiers by which their signal is propagated throughout earth; for the Gleissberg cycle it is by modulation of pressures in the South Atlantic through influence on wind patterns, and for the de Vries cycle it is through modification of NADW, underpinning the conclusions of Bond et al. 2001.

Novello et al. 2012

Why I think it’s important – It argues that solar activity (in this case the de Vries/Suess solar cycle) can influence Brazilian hydroclimate, and that this ~210-year periodicity is present in other climatic records as well.

Balybina and Karakhanyan 2012

Why I think it’s important – It argues that the amplitude and length (corroborating the findings of Lassen and Friis-Christensen) of the 11-year solar cycle influence tree ring growth. This, in my opinion, (see previous papers on solar activity and trees) represents a connection between solar activity and climate.

Bochnicek et al. 2012

Why I think it’s important – It argues that solar activity can modulate atmospheric circulation and produce conditions resembling different phases of the NAO.

Zhou and Tung 2013

Why I think it’s important – It argues in favor of the bottom-up amplification mechanism, and that solar activity, including the Schwabe cycle, can influence evaporation, convection, latent heating of the troposphere, and heat transport to the poles.

Soon and Legates 2013

Why I think it’s important – It argues that solar variations can modulate the EPTG, that this provides a significant amplification mechanism linking solar activity and North Atlantic and Arctic climate (as discussed in Soon 2005 and Soon 2009), and that since EPTG represents global climate well, solar variations can be amplified to change global climate.

Kokfelt and Muscheler 2013

Why I think it’s important – It argues that solar activity can influence Fennoscandianf hydroclimate and temperature through modulation of the NAO and temperature of the waters off of Norway.

Asmerom et al. 2013

Why I think it’s important – It argues that solar activity is coupled in a complex manner with the ocean and atmosphere, and that solar variations can modulate Northern Hemisphere monsoons.

Kobashi et al. 2013

Why I think it’s important – It argues that high solar activity can cool Greenland by influence the AMOC, which in turn modulates atmospheric circulation, such as the NAO/AO. These circulation anomalies in turn lower Greenland’s temperature.

Scaife et al. 2013

Why I think it’s important – It argues that solar activity is connected to the NAO/AO through atmospheric circulation, ocean heat content, and its feedbacks into the atmosphere.

Patterson et al. 2013

Why I think it’s important – It argues that solar activity can modulate cloud cover, the AL, upwelling, climate, and primary productivity in the northeast Pacific region.

Czymzik et al. 2013

Why I think it’s important – It argues that solar variations can modulate southern German flood and cyclonic intensity by influencing temperature gradients and atmospheric circulation.

Galloway et al. 2013

Why I think it’s important – It argues that solar activity, including the de Vries/Suess ~208-year solar cycle, by modulating the AL, can influence storminess, precipitation, and climate.

Wirth et al. 2013a

Why I think it’s important – It argues that solar activity can influence atmospheric circulation and produce conditions similar to the negative phase of the NAO, by which it can modulate Alpine European floods.

Gupta et al. 2013

Why I think it’s important – It argues that stratosphere-troposphere coupling, by amplifying the solar signal, provide a mechanism for the observed ~208-year de Vries/Suess solar cycle periodicity in historical ISM reconstructions. It also argues that  North Atlantic (where there seems to be a strong solar signal, see Bond et al. 2001), South Asian, and East Asian climates are linked through ISM precipitation and solar activity.

Wirth et al. 2013b

Why I think it’s important – It argues that solar activity can modulate Central Alpine floods by changing surface temperature (and thus the Hadley cell), as well as North Atlantic circulation patterns.

Wurtzel et al. 2013

Why I think it’s important – It argues that solar activity can significantly influence Caribbean SSTs, that it has in the past, and that it does so by influencing slow marine processes (like the AMOC, an important component of oceanic circulation) as well as trade winds.

Liu et al. 2013

Why I think it’s important – It argues that solar activity can drive global climate changes through forcing atmospheric reorganizations, which rapidly transmit the solar signal around the globe.

Ogurtsov et al. 2013

Why I think it’s important – It argues that the Gleissberg solar cycle is present in temperature proxies from Northern Fennoscandia.

Gray et al. 2013

Why I think it’s important – It argues that solar activity, including the 11-year solar cycle, can influence the NAO, produce conditions resembling the PDO, and influence North Atlantic and European winter climate.

Raspopov et al. 2013

Why I think it’s important – It argues that solar activity contributed to the destruction of ancient civilizations, and that it could’ve forced movement of glacial mass through a global reorganization of atmospheric circulation.

Xu et al. 2014

Why I think it’s important – It argues that there is a ~500 year solar cycle, and that solar activity can influence the NAO/AO and NADW, with large climatic implications for East Asia.

Katsuki et al. 2014

Why I think it’s important – It argues that solar activity can influence the Bering Sea ecosystem and microclimate through modulation of glacial melt and spring ice-retreat, which could be regarded as feedbacks or amplifiers of the solar effect.

Tiwari and Rajesh 2014

Why I think it’s important – It argues that solar variations, through a complex system of Sun-climate couplings and feedbacks, can amplify the hydrographics system of regional climates and modulate groundwater levels.

Ogurtsov and Oinonen 2014

Why I think it’s important – It argues that the Gleissberg solar cycle is present in temperature proxies from Greenland and Antarctica.

Moffa-Sanchez et al. 2014

Why I think it’s important – It argues that solar activity can modulate regional atmospheric circulation and blocking events, and also possibly the AMOC, and thus provide explanation for some past climate phenomena.

Maghrabi and Al Dajani 2014

Why I think it’s important – It argues that solar activity can influence atmospheric water vapor content.

Jimenez-Espejo et al. 2014

Why I think it’s important – It argues that solar activity can modulate Saharan dust supply, which has been linked to surface temperature and tropical cyclone formation.

Zhao and Wang 2014

Why I think it’s important – It argues that solar activity can robustly influence the East Asian monsoon, and that it can influence atmospheric dynamics and cause seesaw phenomena.

Liu et al. 2014a

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can modulate the PNA (so that the PNA serves as an important conduit between the Sun and climate) and thus atmospheric circulation, by which solar variability can influence North American temperature and precipitation. The magnitude of the solar modulation is such that 67% and 14% of the respective PNA-induced temperature and precipitation anomalies result from the Sun.

Liu et al. 2014b

Why I think it’s important – It argues that solar activity can influence the PNA, and that the Dalton and Damon minimums of solar activity may’ve been associated with solar-induced PNA patterns.

Knudsen et al. 2014

Why I think it’s important – It argues that solar activity can influence the AMO, which is a highly important natural climate oscillation, and that this approach links two competing views on the AMO.

Lim et al. 2014

Why I think it’s important – It argues that solar activity and GHGs contributed nearly equally to the recent global temperature rise, and, depending on the method used, the Sun explains from 30-50 or 56-60% of the warming.

Zhang et al. 2014

Why I think it’s important – It argues that solar activity can influence ENSO, and that this relationship probably occured throughout much of the Holocene.

Adolphi et al. 2014

Why I think it’s important – It finds support for the top-down mechanism, and argues that solar activity can induce high-pressure blocking systems near Greenland.

Scafetta and Willson 2014

Why I think it’s important – It argues that there is an upward trend during solar cycles 21 and 22, and that because of this CMIP5 models may underestimate the solar contribution to climate change over that period.

Maliniemi et al. 2014

Why I think it’s important – It argues that solar activity, including the Schwabe cycle, can modulate winter surface temperatures, and that solar variability may influence the NAO, since during a decline in solar activity temperatures resembling the positive phase of the NAO are produced.

Willson 2014

Why I think it’s important – It affirms the conclusions of Scafetta and Willson 2014, except also for solar cycles 21-23, and also the argument that solar activity has a larger role in recent climate change than models assume.

Chu et al. 2014

Why I think it’s important – It argues that solar activity, including the Gleissberg and de Vries/Suess solar cycles, is strongly linked with monsoon rainfall in northeast China.

Shi et al. 2014

Why I think it’s important – It argues that solar activity may be a critical driver of the SASM on multidecadal timescales, through modulation of SASM winds by modification of the north-south temperature gradient.

Wormer et al. 2014

Why I think it’s important – It argues that the de Vries/Suess ~200 year solar cycle is present in reconstructed SSTs, and that the solar signal is likely amplified by a variety of ecological and environmental factors.

Moreira-Turcq et al. 2014

Why I think it’s important – It argues that solar activity could be at least partially responsible for an extreme Amazon flooding event 2,700 years ago through influence on the ITCZ and AMOC, and thus South American precipitation.

Sagir et al. 2015

Why I think it’s important – It argues that solar activity can influence the QBO.

Howard et al. 2015

Why I think it’s important – It argues that solar forcing during a solar cycle is 8 times that of the irradiance change, that solar activity and ENSO explain most of detrended sea level variations, and that there may be an amplification mechanism increasing the solar impact on climate.

Tiwari et al. 2015

Why I think it’s important – It argues that solar activity, including the Schwabe and Hale solar cycles, can drive Indian temperature variability through modulation of ENSO.

Sfica et al. 2015

Why I think it’s important – It argues that solar activity can influence North Atlantic sea level pressure, the NAO and the PNA.

Soon et al. 2015

Why I think it’s important – It argues that the Northern Hemisphere warming of 1880-1940 is comparable to the warmth of today, and that solar activity has been the dominant influence on Northern Hemisphere temperatures during the time period studied. Thus, it could explain much of the warming over that period.

Jiang et al. 2015

Why I think it’s important – It argues that atmospheric and oceanic circulation are important mediators of the Sun-climate link, that North Atlantic climate follows solar activity closely, and that solar activity may be able to influence deepwater formation.

Ogurtsov et al. 2015

Why I think it’s important – It argues that the Gleissberg solar cycle is present in temperature proxies for the whole boreal zone of the Northern Hemisphere.

Chen et al. 2015

Why I think it’s important – It argues that both the top-down and bottom-up mechanisms amplify the solar signal in Eurasia, that circulation patterns can be influenced by solar activity, and that solar activity can modify the LOTC, which also amplifies the solar signal.

Song et al. 2015

Why I think it’s important – It argues that solar activity can modulate central Asian hydroclimate, and that in the past multiple solar cycles of many periodicities have done so.

Kobashi et al. 2015

Why I think it’s important – It argues that high solar activity actually cooled Greenland in the late 20th century (providing a natural explanation for those anomalies), and that through a series of feedbacks, the Sun can also control the AMOC.

Thieblemont et al. 2015

Why I think it’s important – It argues that solar activity can influence the NAO, that the solar cycle contribution to NAO is 4%, and that even this small contribution has large implications for those climatic phenomena which are influenced by the NAO.

Usoskin et al. 2015

Why I think it’s important – It argues that the Maunder Minimum was indeed a time of exceptionally low solar activity, much lower than the current (24th) solar cycle, contradicting claims such as those made in Clette et al. 2014.

Yan et al. 2015

Why I think it’s important – It argues that solar activity, as it represents an external forcing on climate, could influence the ITCZ, and affirms the assertion that low monsoon precipitation in the LIA was caused by low solar activity.

Douglass and Knox 2015a

Why I think it’s important – It argues that solar activity can influence ENSO by phase-locking tropical Pacific SSTs to certain states.

Douglass and Knox 2015b

Why I think it’s important – It affirms the conclusions of Douglass and Knox 2015a, but this time for the global ocean (at both 700 meters and 2000 meters), and also argues that the ENSO effect induced by solar activity influences global ocean temperatures.

Liu et al. 2015

Why I think it’s important – It argues that solar activity, including the ~208-year de Vries/Suess cycle, was a primary contributor to Asian Monsoon variability in the past, and that the oceans and atmosphere are involved as positive feedbacks to the solar forcing.

LongBin et al. 2015

Why I think it’s important – It argues that solar activity, including the Hale and Gleissberg cycles, can influence ocean dynamics and thus sea ice variability. In addition, it finds evidence for the MWP and LIA and argues that these events were connected to solar activity.

Andrews et al. 2015

Why I think it’s important – It argues that there is a significant, lagged response of the NAO to the 11-year solar cycle, and that the influence of the Sun goes beyond the heating from solar activity and its response, because the North Atlantic carries a memory of the solar forcing which then produces the lagged response.

Wang et al. 2015

Why I think it’s important – It argues that solar activity, including the 27-day solar cycle, can modulate HO2 levels in the atmosphere, which in turn modulate ozone concentration, which of course influences climate.

Schieferdecker et al. 2015

Why I think it’s important – It argues that solar activity can modulate tropical tropopause temperatures by modifying tropopause (and thus stratospheric, by tropopause-stratosphere coupling) water vapor content.

Timmermans 2015

Why I think it’s important – It argues that heat from solar variations stored under Arctic sea ice can significantly influence its cover, and that it did so in the past (e.g., by reducing 2008 growth end season ice cover by 25%).

Liu et al. 2015

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can modulate ENSO, and that increased (decreased) solar activity, by strengthening (weakening) the Walker circulation, can produce ENSO-negative (ENSO-positive) conditions in the tropical Pacific.

Thomas et al. 2015

Why I think it’s important – It argues that solar 27-day variations can influence mesospheric water vapor and temperature, both of which influence clouds, so also possibly cloud cover.

Antico and Torres 2015

Why I think it’s important – It argues that solar activity, including the 11-year Schwabe cycle, can influence streamflow of the Amazon River and thus the global water cycle, since the Amazon is such a major part of it.

Curtis and Douglass 2016

Why I think it’s important – It affirms the conclusions of Douglass and Knox 2015a, but this time for precipitation in that region.

Hassan et al. 2016

Why I think it’s important – It argues that there is a significant connection between sunspots (and thus solar activity) and ENSO.

Katsuki et al. 2016

Why I think it’s important – It argues that solar activity can influence the EASM, which in turn influences typhoon intensity on the Korean Peninsula, and that because of low solar activity during the Maunder Minimum, more typhoons struck China and the Korean Peninsula.

Sha et al. 2016

Why I think it’s important – It argues that solar activity, including the 11-year solar cycle, can and has modulated West Greenland ice amount, and that distant sea ice can be influenced by the solar signal because sea-ice transport from the Arctic ocean could be affected through a sea ice-ocean-atmosphere feedback mechanism.

Usoskin et al. 2016

Why I think it’s important – It argues that there were solar minimums in 1800 and 1900, and that recent solar activity is unique in the last 250 years (see Usoskin et al. 2015 for significance).

Turney et al. 2016

Why I think it’s important – It argues that solar activity can modulate Southern Hemisphere Westerly airflow, with important implications for understanding historical climate.

Koyohama and Wallace 2016

Why I think it’s important – It argues that solar (as well as lunar) variability can influence global rainfall.

Yamakawa et al. 2016

Why I think it’s important – It argues that solar activity has a strong influence on SSTs in a significant portion of the globe, that solar activity can influence geopotential heights and atmospheric circulation, and that solar activity can have an influence on climate from the troposphere, stratosphere, and sea surface.

Faust et al. 2016

Why I think it’s important – It argues that solar activity can influence the NAO (and thus atmospheric circulation), Northern Hemisphere glacier variability, and demographic trends, corroborating the work of Shindell et al. 2001, Ineson et al. 2011, and Martin-Puertas et al. 2012.

Chiodo et al. 2016

Why I think it’s important – It argues that a significant reduction in solar activity produces a somewhat larger-than-expected response in the Northern Hemisphere, mitigating 40% of the global warming from humans over that period, and that such a reduction would influence sea-ice cover and lead to a significant cooling over Russia due to the top-down mechanism.

Haig and Nott 2016

Why I think it’s important – It argues that solar activity drives decadal, interdecadal, and centennial cycles in tropical cyclones in Australia.

Czymzik et al. 2016a

Why I think it’s important – It finds support for a top-down mechanism influence on hydroclimate extremes in historical hydroclimate observations of central Europe, and argues that solar activity can affect atmospheric circulation in that region.

Tiwari et al. 2016

Why I think it’s important – It argues that solar activity can induce global temperature oscillations via coupling with the ocean, atmosphere, and climate.

Cullens et al. 2016

Why I think it’s important – It argues that solar activity, including the Schwabe cycle, can significantly influence atmospheric temperature and circulation, including the Southern Hemisphere polar vortex.

Novello et al. 2016

Why I think it’s important – It argues that solar activity is a significant forcing on the South American Monsoon System, and that solar activity may influence the ITCZ.

Hood 2016

Why I think it’s important – It argues that ~27-day solar ultraviolet variations can warm the stratosphere, cool the troposphere, and influence the Brewer-Dobson (mean meridional) circulation and the MJO.

Kaniewski et al. 2016

Why I think it’s important – It argues that solar activity can, through the top-down mechanism, via modification of atmospheric circulation, storm surges, and coastal flooding, influence agricultural losses in the central Mediterranean. The authors also find support for a solar influence on the NAO/AO.

Al-Tameemi and Chukin 2016

Why I think it’s important – It argues that solar activity has a significant effect on global water cycle variations, which can influence temperature as well as being an important part of hydroclimate.

Airapetian et al. 2016

Why I think it’s important – It argues that an active early Sun, one which emitted many superflares (powerful coronal mass injections), could provide an explanation to the Faint Young Sun Paradox, where earth was warm enough to have liquid water but the Sun was seemingly not very active. The Sun could’ve warmed earth by efficient formation of the GHG nitrous oxide in the atmosphere.

Dima and Voiculescu 2016

Why I think it’s important – It argues that solar activity can influence sea level pressure, SSTs and air temperature, and high cloud cover. It also argues that the anomalous cloud cover’s influence on climate is then amplified by long-wave fluxes, increasing the solar signal even more, and that the top-down and bottom-up mechanisms work to reinforce each other.

Fuentes-Santos et al. 2016

Why I think it’s important – It argues that solar activity, through modulation of water temperature and food availability, can influence musssel settlement timing and intensity.

Incarbona et al. 2016

Why I think it’s important – It argues that solar activity can modulate the thermohaline circulation, atmospheric circulation, including the NAO, and thus Mediterranean climate.

Bernal et al. 2016

Why I think it’s important – It argues that solar activity can modulate the SASM, as well as the SACZ, both having important implications for South American climate.

Gray et al. 2016

Why I think it’s important – It argues that the 11-year solar cycle can influence the NAO and winter blocking over Europe and the Atlantic, as well as that the blocking signal from the Schwabe cycle is more significant than that from ENSO and AMO.

Czymzik et al. 2016b

Why I think it’s important – It argues that solar activity, including the Gleissberg and de Vries/Suess solar cycles, can modulate atmospheric circulation and thus northeastern German climate.

Madhav Haridas et al. 2016

Why I think it’s important – It argues that solar activity can influence nocturnal thermospheric meridional winds, at least over India.

Solomina et al. 2016

Why I think it’s important – It argues that glacial movements over the past 2000 years correspond with solar activity. In addition, it argues that the LIA was a global phenomenon.

Salas et al. 2016

Why I think it’s important – It argues that solar activity, including the Hale solar cycle, can modulate hydrology and hydrogeology by influencing ENSO.

Perone et al. 2016

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence tree ring growth.

Rojo-Garibaldi et al. 2016

Why I think it’s important – It argues that solar activity can modulate tropical cyclone activity.

Hall et al. 2016

Why I think it’s important – It argues that solar activity can, with a lag time, influence the jet stream, corroborating the findings of Scaife and Gray et al. 2013, and Andrews et al. 2015.

Huo and Xiao 2016

Why I think it’s important – It argues that the 2015-2016 El Nino was at least partially caused by high solar activity (but that high solar activity can also cause ENSO-negative conditions, consistent with the results of van Loon et al. 2007), and that solar activity can influence ENSO.

Sunkara and Tiwari 2016

Why I think it’s important – It argues that solar activity, including the Schwabe solar cycle, can influence ENSO and atmospheric circulation, and thus Indian climate.

Thurairajah et al. 2016

Why I think it’s important – It argues that solar activity can influence cloud cover.