A highlight of recent research supporting the climate realist perspective #12

I have come across many scientific papers published the past calendar year which support the climate realist perspective, and thought them of such significance that I should share them here, in my climate realist paper update series of blog posts. However, I have not gotten around to sharing them. So, I am setting out to share with you as much climate realist research that has been published this year as I can, because what I have shared so far is only a fraction of all the papers that I am sitting on that are significant enough to be shared. Be prepared-there will be more posts like this coming yet, with both older and newer papers from this year, and hopefully I will be able to turn out these posts in quick succession.

First is How Has Human-Induced Climate Change Affected California Drought Risk?. It argues that, contrary to popular belief, human-caused climate change actually made California’s current drought less likely, and that the current devastating impacts of the drought are not a consequence of long-term climate change. This is great news, and even if, as other studies claim, humans have made California’s drought worse, it’s likely that the drought was overwhelmingly caused by natural variability.

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A graph of the hydroclimatic variability of the American West since 800. From The Mercury News.

Second is What caused the recent “Warm Arctic, Cold Continents” trend pattern in winter temperatures?. It argues that recent ice loss in the Arctic did not cause, as some have suggested, the recent cooling trend in midlatitude winter temperatures, that this cooling trend is the result of natural variability, and further, that Arctic sea ice loss actually reduces variability in temperatures and risk of cold extremes, corroborating other research highlighted here (also see below), and dealing a further blow to the theory linking Arctic sea ice loss to extreme weather (particularly extreme cold) in the midlatitudes.

Third is Future Arctic sea ice loss reduces severity of cold air outbreaks in midlatitudes. It argues, similarly to the above paper, that retreating Arctic sea ice does not increase severity and/or frequency of cold air outbreaks in the midlatitudies, but instead actually decreases their severity. This is great news, since reduced midlatitude winter cold outbreak severity would lead to less deaths from cold, and it deals yet a further blow to the theory linking Arctic sea ice loss to extreme weather (particularly extreme cold) in the midlatitudes.

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A highlight of recent research supporting the climate realist perspective #11

As I mentioned in my last post, I have come across many scientific papers published the past calendar year which support the climate realist perspective, and thought them of such significance that I should share them here, in my climate realist paper update series of blog posts. However, I have not gotten around to sharing them. So, I am setting out to share with you as much climate realist research that has been published this year as I can, because what I have shared so far is only a fraction of all the papers that I am sitting on that are significant enough to be shared. Be prepared-there will be more posts like this coming yet, with both older and newer papers from this year, and hopefully I will be able to turn out these posts in quick succession.

First is Modelling coffee leaf rust risk in Colombia with climate reanalysis data (press release here). It finds that climate change will not actually promote a fungal disease which decimates coffee crops, as has been feared. This is great news, since it means that poor countries which produce coffee can reduce their fears of a global warming-induced devastation of coffee crops.

Second is The Resolution Dependence of Contiguous U.S. Precipitation Extremes in Response to CO2 Forcing. It argues that there is no evidence for extreme precipitation changes attributable to climate change in the United States, at least in recent times. This is great news, since climate change is usually associated with more frequent and heavy extreme precipitaiton, and despite its highly controversial nature, other research seems to corroborate the view that the hydrological cycle’s link to increased CO2 is not quite as straightforward as some would have us believe (also see below).

Third is Characterizing Recent Trends in U.S. Heavy Precipitation. It argues that recent increases in heavy daily precipitation can be attributed largely to natural oceanic variability, with anthropogenic forcing playing only a limited role. This is great news, and is especially interesting in light of the research highlighted above, further supporting the climtate realist view that while anthropogenic-induced climate change will alter the hydrological cycle, the current paradigm of simple intesification and increase of extremes is a gross oversimplification.

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A geographical representation of trends in United States flooding. Note the lack of any coherent trend. From Archfield et al. 2016.

 

 

A highlight of recent research supporting the climate realist perspective #10

I have come across many scientific papers published these past two calendar years which support the climate realist perspective, and thought them of such significance that I should share them here, in my climate realist paper update series of blog posts. However, I have not gotten around to sharing them. So, I am setting out to share with you as much climate realist research that has been published this year as I can, because what I have shared so far is only a fraction of all the papers that I am sitting on that are significant enough to be shared. Be prepared-there will be more posts like this coming yet, with both older and newer papers from this year, and hopefully I will be able to turn out these posts in quick succession.

Please also note that I am constantly working to improve this blog; it is under construction, as the header says. So this will mean that old posts and resources are subject to change, but for the better.

First is Elevated CO2 maintains grassland net carbon uptake under a future heat and drought extreme (press release here). As mentioned above, this paper, as with some others, is quite old by this post series’ standards, but it’s highly important, and worth sharing. It finds that the beneficial effects of rising CO2 on plants, during future projected extreme climatic events (such as heatwaves), outweighs the negative effects of such extreme climatic events on net carbon uptake. This is great news, since it implies a negative feedback, because increased carbon uptake from the atmosphere means more plant growth and less carbon in the air, so less warming. This research is in stark contrast to some research projecting carbon uptake decreases with warming, but some other research casts doubts on fears over a strong positive feedback from carbon uptake decreases as well.

Second is Increasing Winter Precipitation over Arid Central Asia under Global Warming. It finds that winter precipitation in the highly arid region of Central Asia has been increasing recently, and will continue to increase with further global warming. In addition, while the paper finds no significant annual trend for all of Central Asia, Southeast Central Asia displays robust increases in precipitation in all seasons. This is great news, and is especially interesting in light of the next paper I will highlight.

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Trends in winter precipitation across Central Asia. Note that precipitation in all subregions is increasing significantly. From Song and Bai 2016.

Third is Elevated CO2 as a driver of global dryland greening. It finds that the world’s dry regions are greening, and that this is likely due to increases in CO2 concentration (similar conclusions about global greening have been reached by other recently published papers, press releases here and here). The rising CO2 levels make plant water saving more efficient and thus increase available soil water and stimulate plant growth. As other posts have noted, the effects of increasing CO2 are diverse, and both positive and negative. One highly important positive effect of increasing CO2 levels is the numerous benefits plants receive from having what is essentially more food. This is great news, and as mentioned above, this research is especially interesting since increasing CO2, through modification of the hydrological cycle, is also apparently increasing precipitation in some dry regions of the world, so plants may be receiving, at least in some areas, a double benefit from rising CO2 levels.

A highlight of recent research supporting the climate realist perspective #9

I have come across three scientific papers published recently, all of which support the climate realist perspective, and thought them of such significance that I should share them here, in my climate realist paper update series of blog posts.

First is Colluvium supply in humid regions limits the frequency of storm-triggered landslides (press release here), published in Scientific Reports. It argues that despite projected increases in extreme rainfall, landslides will, on the whole, most likely not be significantly affected by climate change. This is great news, since increasing landslides in a warming world would inevitably result in increased damage to life and property, and it goes against the conventional wisdom on landslides and rainfall, which are usually assumed to be strongly connected. And even this is assuming that the hydrological cycle will intensify as predicted, but the common opinion opinion on this issue may be oversimplistic, as these papers show.

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Changes in land precipitation around the globe since 1940. Note the lack of a cohesive trend. From Sun et al. 2012.

Second is The record-breaking 2015 hurricane season in the eastern North Pacific: An analysis of environmental conditions (press release here), published in Geophysical Research Letters. It argues that the record-breaking 2015 Eastern North Pacific hurricane season, which produced powerful storms such as Hurricane Patricia, the strongest tropical storm on record in the Western Hemisphere, was due to the combined effects of a positive Pacific Meridional Mode and strong El Nino conditions. Since both of these oscillations are natural, this is great news, since it means, despite what some of the hype at the time said, that human activities cannot be blamed, at least to a significant degree, for the unusually active season, and thusHurricane Patricia.

Third is Twenty-five winters of unexpected Eurasian cooling unlikely due to Arctic sea-ice loss, published in Nature Geoscience. It argues, dealing a further blow to the “warm Arctic-cold Northern Hemisphere winter” proposal, that recent, unexpected Eurasian winter cooling was not likely due to Arctic sea ice loss. This is great news, since colder winters would result in more cold-related mortality, and Arctic sea ice is likely to keep on declining as human-induced warming continues. Warmer winters, on the other hand, one of the projected effects of global warming, are often neglected as a beneficial effect of climate change, but this research lends further credence to the idea that warmer winters may indeed come about as a result of human-induced warming, which reduce cold-related mortality and save lives. As a side note, one of the authors, Dr. John C. Fyfe, has come out with research supporting the climate realist perspective before, such as here and here.

A highlight of recent research supporting the climate realist perspective #8

I have come across four scientific papers published recently, all of which support the climate realist perspective, and thought them of such significance that I should share them here, in my climate realist paper update series of blog posts.

First is Fragmented patterns of flood change across the United States (press release here), published in Geophysical Research Letters. It argues that much of the United States has experienced no change in floods, and that no countrywide trend is observable. This is great news, since according to the paper, a climate change influence in flooding in the United States as a whole, at least currently, is not apparent. This flies in the face of many alarmist statements, such as that the effects of climate change on floods in the United States are already observable. However, this paper’s results are corroborated by multiple independent studies finding little variation of late in the hydrological cycle, despite the ongoing, partially human-induced global warming.

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Changes in flood patterns across the United States over the past 75 years. Note the lack of cohesive, country-wide change, at least in one direction. From Archfield et al. 2016.

Second is Modification of land-atmosphere interactions by CO2 effects: implications for summer dryness and heatwave amplitude, published in Geophysical Research Letters. It argues, similarly to another recent paper, that beneficial effects of rising CO2 on plants, such as increased leaf area and water use efficiency, will help mitigate projected increases in heat wave and drought impacts. This is also great news, and further lends credence to the idea that the beneficial effects of rising CO2 will at least partially offset some of the negative effects.

Third is Assessing recent trends in high-latitude Southern Hemisphere surface climate (press release here), published in Nature Climate Change. It argues that recent trends in high-latitude Southern Hemisphere climate, such as sea-ice extent, temperature, and sea level pressure, (with the exception of the Southern Annular Mode) are within the bounds of the past 200 years and can be explained by natural variability. This result is especially fascinating, since humans have spewed so much CO2 and other GHGs into the atmosphere and yet natural variability can still overwhelm that signal. This thus implies that climate sensitivity may be on the low end of the IPCC’s range: 1.5 to 4.5 degrees Celsius for a doubling of CO2 in the atmosphere.

Fourth is Decrease in climatic conditions favouring floods in the south-east of Belgium over 1959–2010 using the regional climate model MAR, published in International Journal of Climatology. It argues that warming in Belgium actually decreased the chances for conditions favorable for floods to develop. This result is also fascinating, and again contradicts the simplistic view that climate change will simply make virtually climatic extremes worse everywhere.

As I noted before, evidence accumulates seemingly every passing week supporting the climate realist perspective. One can only hope that such papers will get more recognition than they currently do.

A highlight of recent research supporting the climate realist perspective #7

I have come across a scientific paper published recently, which supports the climate realist perspective, and thought it of such significance that I should share it here, in my climate realist paper update series.

The paper in question (press release here) has been published in Science Advance. It argues that recent unprecedented tree growth in the Tibetan Plateau is due to CO2 increases. The paper finds that the direct effects of increased CO2 on plant growth, from fertilization, and indirect effects, from melting of permafrost caused by CO2-induced warming, which makes more nutrients and water from the snow available to the trees, work in tandem to increase forest growth and thus defy predictions that climate change will have a negative impact on forests worldwide. This is great news, and the increase in forest growth will also help to remove CO2 from the atmosphere, providing a negative feedback. This work is especially interesting in light of recent papers (press releases here and here) arguing that humans are greening the earth, the former of which, corroborating the results of Silva et al. 2016, finds that the Tibetan Plateau is greening mainly because the indirect effects of CO2 (as opposed to most of the rest of the earth): those effects resulting from CO2-induced warming. And as always, it’s important to remember other beneficial effects (while also considering the negative effects, since some beneficial effects simply offset some negative effects from rising CO2!), be they direct or indirect, of rising CO2 levels, leve such as offsetting much of the negative effects of projected drought increases.

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Rate of tree growth over time. Note the recent, rapid increases. From Silva et al. 2016

A highlight of recent research supporting the climate realist perspective #6

I have come across a scientific paper published recently, which supports the climate realist perspective, and thought it of such significance that I should share it here, in my climate realist paper update series of blog posts.

The paper in question (press release here) has been published in Proceedings of the National Academy of Sciences, and it makes an interesting point regarding droughts and climate change. It argues that the beneficial effects from rising CO2, such as modified plant water usage, can offset much of the negative effects from droughts caused by rising CO2. Because of rising CO2, plants need less water, keep more of it on land, and thus are less affected by the projected rise in frequency and intensity of droughts, argues Swann et al. 2016. In fact, the paper argues that though 70% of the earth is projected to experience increases in droughts over the 21st century, this number drops to 37% if you include the positive effects of CO2 on plants. This is great news, especially for the places which the paper finds will not be affected by the rise in droughts very much: Central Africa, China, the Middle East, East Asia, and most of Russia. This most certainly supports the climate realist perspective, as do so many other papers, by again showing that at least some of the alarm associated with climate change is not deserved. Furthermore, projected drought and precipitation patterns may not necessarily correspond with observations, as shown by multiple independent studies.

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Changes in global drought patterns since 1950. Note the lack of a strong trend. From Sheffield et al. 2012.