Updated: Climates Don’t Start Wars, People Do

Update July 14

A new study has looked into the Syrian civil war, which has been the poster child for those claiming climate causes  human conflict.  h\t to Mike Hulme who posted Climate Change and the Syrian Civil War Revisited The study concluded:

“For proponents of the view that anthropogenic climate change will become a ‘threat multiplier’ for instability in the decades ahead, the Syrian civil war has become a recurring reference point, providing apparently compelling evidence that such conflict effects are already with us. According to this view, human-induced climatic change was a contributory factor in the extreme drought experienced within Syria prior to its civil war; this drought in turn led to large-scale migration; and this migration in turn exacerbated the socio-economic stresses that underpinned Syria’s descent into war. This article provides a systematic interrogation of these claims, and finds little merit to them. Amongst other things it shows that there is no clear and reliable evidence that anthropogenic climate change was a factor in Syria’s pre-civil war drought; that this drought did not cause anywhere near the scale of migration that is often alleged; and that there exists no solid evidence that drought migration pressures in Syria contributed to civil war onset. The Syria case, the article finds, does not support ‘threat multiplier’ views of the impacts of climate change; to the contrary, we conclude, policymakers, commentators and scholars alike should exercise far greater caution when drawing such linkages or when securitising climate change.”  (my bold)

Original Post

Once again the media are promoting a link between climate change and human conflicts. It is obvious to anyone in their right mind that wars correlate with environmental destruction. From rioting in Watts, to the wars in Iraq, or the current chaos in Syria, there’s no doubt that fighting degrades the environment big time.

What is strange here is the notion that changes in temperatures and/or rainfall cause the conflicts in the first place. The researchers that advance this claim are few in number and are hotly disputed by many others in the field, but you would not know that from the one-sided coverage in the mass media.

The Claim

Lately the fuss arises from this study: Climate, conflict, and social stability: what does the evidence say?, Hsiang, S.M. & Burke, M. Climatic Change (2014) 123: 39. doi:10.1007/s10584-013-0868-3

Hsiang and Burke (2014) examine 50 quantitative empirical studies and find a “remarkable convergence in findings” (p. 52) and “strong support for a causal association” (p. 42) between climatological changes and conflict at all scales and across all major regions of the world. A companion paper by Hsiang et al. (2013) that attempts to quantify the average effect from these studies indicates that a 1 standard deviation (σ) increase in temperature or rainfall anomaly is associated with an 11.1 % change in the risk of “intergroup conflict”.1 Assuming that future societies respond similarly to climate variability as past populations, they warn that increased rates of human conflict might represent a “large and critical impact” of climate change.

The Bigger Picture

This assertion is disputed by numerous researchers, some 26 of whom joined in a peer-reviewed comment: One effect to rule them all? A comment on climate and conflict, Buhaug, H., Nordkvelle, J., Bernauer, T. et al. Climatic Change (2014) 127: 391. doi:10.1007/s10584-014-1266-1

In contrast to Hsiang and coauthors, we find no evidence of a convergence of findings on climate variability and civil conflict. Recent studies disagree not only on the magnitude of the impact of climate variability but also on the direction of the effect. The aggregate median effect from these studies suggests that a one-standard deviation increase in temperature or loss of rainfall is associated with a 3.5 % increase in conflict risk, although the 95 % highest density area of the distribution of effects cannot exclude the possibility of large negative or positive effects. With all contemporaneous effects, the aggregate point estimate increases somewhat but remains statistically indistinguishable from zero.

To be clear, this commentary should not be taken to imply that climate has no influence on armed conflict. Rather, we argue – in line with recent scientific reviews (Adger et al. 2014; Bernauer et al. 2012; Gleditsch 2012; Klomp and Bulte 2013; Meierding 2013; Scheffran et al. 2012a,b; Theisen et al. 2013; Zografos et al. 2014) – that research to date has failed to converge on a specific and direct association between climate and violent conflict.

The Root of Climate Change Bias

The two sides have continued to publish and the issue is far from settled. Interested observers describe how serious people can disagree so frequently about such findings in climate science.

Modeling and data choices sway conclusions about climate-conflict links, Andrew M. Linke, and Frank D. W. Witmer, Institute of Behavioral Science, University of Colorado, Boulder, CO 80309-0483 here

Conclusions about the climate–conflict relationship are also contingent on the assumptions behind the respective statistical analyses. Although this simple fact is generally understood, we stress the disciplinary preferences in modeling decisions.

However, we believe that the Burke et al. finding is not a “benchmark” in the sense that it is the scientific truth or an objective reality because disciplinary-related modeling decisions, data availability and choices, and coding rules are critical in deriving robust conclusions about temperature and conflict.

After adding additional covariates (models 4 and 6), the significant temperature effect in the Burke et al. (1) model disappears, with sociopolitical variables predicting conflict more effectively than the climate variables. Furthermore, this specification provides additional insights into the between- and within-effects that vary for factors such as political exclusion and prior conflict.


Sociopolitical variables predict conflict more effectively than climate variables. It is well established that poorer countries, such as those in Africa, are more likely to experience chronic human conflicts. It is also obvious that failing states fall into armed conflicts, being unable to govern effectively due to corruption and illegitimacy.

It boggles the mind that activists promote policies to deny cheap, reliable energy for such countries, perpetuating or increasing their poverty and misery, while claiming such actions reduce the chances of conflicts in the future.

Halvard Buhaug concludes (here):

Vocal actors within policy and practice contend that environmental variability and shocks, such as drought and prolonged heat waves, drive civil wars in Africa. Recently, a widely publicized scientific article appears to substantiate this claim. This paper investigates the empirical foundation for the claimed relationship in detail. Using a host of different model specifications and alternative measures of drought, heat, and civil war, the paper concludes that climate variability is a poor predictor of armed conflict. Instead, African civil wars can be explained by generic structural and contextual conditions: prevalent ethno-political exclusion, poor national economy, and the collapse of the Cold War system.

Footnote:  The Joys of Playing Climate Whack-A-Mole

Dealing with alarmist claims is like playing whack-a-mole. Every time you beat down one bogeyman, another one pops up in another field, and later the first one returns, needing to be confronted again. I have been playing Climate Whack-A-Mole for a while, and if you are interested, there are some hammers supplied below.

The alarmist methodology is repetitive, only the subject changes. First, create a computer model, purporting to be a physical or statistical representation of the real world. Then play with the parameters until fears are supported by the model outputs. Disregard or discount divergences from empirical observations. This pattern is described in more detail at Chameleon Climate Models

This post is the latest in a series here which apply reality filters to attest climate models.  The first was Temperatures According to Climate Models where both hindcasting and forecasting were seen to be flawed.

Others in the Series are:

Sea Level Rise: Just the Facts

Data vs. Models #1: Arctic Warming

Data vs. Models #2: Droughts and Floods

Data vs. Models #3: Disasters

Data vs. Models #4: Climates Changing

Climate Medicine

Beware getting sucked into any model.

Researchers Against CO2

The media are reporting stories with a new theme: More CO2 is bad for plant life. This flies in the face of biochemistry, but the activist motivation is clear: They want people thinking CO2 is bad in every way. They don’t want the warming scare undermined by the idea that CO2 along with warming actually helps plant life and agriculture.

The current stories are coming from researchers involved with an outdoor laboratory site called Jasper Ridge, affiliated with Stanford University, my alma mater and home to famous alarmist Stephen Schneider (deceased). The headlines are occasioned by a new paper appearing Sept. 5 in the journal Proceedings of the National Academy of Sciences, authored by Chris Field, director of the Stanford Woods Institute for the Environment..

Headlines Claim, Details Deny

Headlines and claims like those below are appearing this week, but as we shall see, the details do not support the conclusions claimed; a leap of faith (bias) is required.

Warmer, wetter climate would impair California grasslands, 17-year experiment finds

“There’s been some hope that changing climate conditions would lead to increased productivity of grasses and other plants that draw down carbon dioxide from the atmosphere,” said study lead author Kai Zhu, a global ecologist and data scientist at Rice “In northern California, it was hypothesized that net grassland productivity might increase under the warmer, wetter conditions that are predicted by most long-term climate models. Our evidence disproves that idea.”

Future climate change field test doesn’t make Earth greener

Plants like carbon dioxide — the main heat-trapping gas. Some people argue that because of that, climate change isn’t so bad and will mean greener Earth.  But the experiment’s findings contradict that.  At least in the California ecosystem, plants that received extra carbon dioxide, as well as those that got extra warmth, didn’t grow more or get greener.

Future climate change field test doesn’t make Earth greener

“This experiment really puts to bed the idea of a greener hypothesis where ecosystems save us from the implications of human-induced climate change.”  Chris Field, director of the Stanford Woods Institute for the Environment.Field, whose study appears Monday in the journal Proceedings of the National Academy of Sciences, theorizes that there’s a limit to how much carbon dioxide plants can use.

The Principle of Limiting Factors

Botanists subscribe to the principle that each species has a range of conditions that it can tolerate, and each factor has an ideal level for that species.  When a factor deviates from ideal, it constrains the growth and becomes the limiting factor.

  • The following are regarded as the most important environmental factors
    ·        Temperature
    ·        Moisture supply
    ·        Radiant energy
    ·        Composition of the atmosphere
    ·        Soil aeration and soil structure
    ·        Soil reaction
    ·        Biotic factors
    ·        Supply of mineral nutrients
    ·        Absence of growth-restricting substances

The first four factors can be considered as climate factors, while the others vary for other reasons. Scientists are conducting experiments in many places to measure the effects of climate factors, both singly and in combination.

Empirical Tests of CO2 and Plant Life

With respect to CO2 the Free-Air CO2 Enrichment or FACE technology was developed as a means to enrich the air with CO2 around vegetation while having minimal effects on the surrounding microclimate. Some of those experiments were conducted on various grassland species, many of which were growing naturally in pastures. CO2 science provides details here.

Dr. Sylvan H. Wittwer, professor emeritus of horticulture at Michigan State, describes the results:

Thousands of scientific experiments have been conducted to measure the effects of carbon dioxide enrichment on specific plants. In most green plants, productivity continues to rise up to CO2 concentrations of 1,000 ppm and above. For rice, the optimal CO2 level is between 1,500 and 2,000 ppm. For unicellular algae, the optimal level is 10,000 to 50,000 ppm. Bruce Kimball, a research leader of the Water Conservation Laboratory of the U.S. Department of Agriculture in Phoenix, Arizona, has pulled together nearly 800 scientific observations from around the world measuring the response of food and flower crops to elevated CO2 concentrations. The mean (average) response to a doubling of the CO2 concentration from its current level of 360 ppm is a 32 percent improvement in plant productivity, with varied manifestations in different species.

Dr. Wittwer directed the Michigan Agricultural Experiment Station for 20 years, and chaired the Board on Agriculture of the National Research Council. He provides details on the interaction of CO2 and plants in his article Rising CO2 is Great for Plants

What’s Different about Jasper Ridge

The attempt to overturn vast evidence of CO2 benefiting the biosphere involves manipulating several factors, including non-climatic ones. Chris Field, director of the project in an interview:

In order to create a realistic possible future environment for these grasslands, we’re manipulating four environmental factors. We’re doubling the concentration of atmospheric CO2. It’s currently about four hundred parts per million, or 0.04 percent in the atmosphere. Our targeted level for the experiments is 0.07 percent, seven hundred parts per million, which is a level that, depending on CO2 emissions, we might reach anywhere in the second half of the century.

We’re increasing the average temperature using heat lamps by about three degrees Fahrenheit. This is at the low end of the projections for the second half of the century. But it’s a practical level for us to achieve without a really massive infrastructure.

We’re also adding nitrogen pollution. It’s better known as acid rain. But it’s biologically available nitrogen that comes also from fossil fuel combustion and other industrial processes. We’re adding it at a level that’s typically experienced now in areas in Northern Europe, in the Northeastern U.S., which are relatively polluted.

The fourth environmental factor that we’re manipulating is rainfall. In general, at the worldwide scale, we know that as it gets warmer, the amount of precipitation basically has to increase because more water is evaporating from the ocean. We don’t know whether a given spot will be wetter or dryer. But by having a precipitation increase, we can untangle the interaction between the other treatments and the precipitation, and more or less create a framework where we can evaluate the impact of precipitation in each of the other factors.

The way our experiments are designed is that we have two levels of each of these four major factors, CO2, warming, Nitrogen pollution, and extra precipitation. And we have all of the different combinations of the two levels. So we have all the two treatment combinations, the three treatment combinations, and the four treatment combinations. Each of those is replicated eight times. Because we’re imposing these treatments on a natural ecosystem, we have lots and lots of variability from place to place and time to time. And the only way that we can be confident that we’re seeing the true effects of our treatments and not just environmental variability, is if we have enough replicates of each treatment that we can extract out the signal from the noise.

One of the most unexpected results we’ve had in the Jasper Ridge Global Change Experiment is the realization that under a wide range of conditions, increased atmospheric CO2 does not lead to increased plant growth. In fact, under many conditions, elevated atmospheric CO2 actually prevents plants from taking full advantage of other resources that are available in the environment. This has quite profound implications for our understanding of ecosystem response to global change and for future climate change. If plants, in fact, don’t grow more under elevated carbon dioxide, it means that atmospheric CO2 is likely to grow faster in the future than we have been anticipating. It basically puts a lot more pressure on societies to figure out how to control emissions of carbon dioxide rather than stepping back and hoping that ecosystems will help us solve the fossil fuel problem.

Once we realized this, it was really important to figure out what the mechanism was; because we know from lots of laboratory studies that the instantaneous rate of plant growth or photosynthesis almost always increases under elevated atmospheric CO2 . We did a variety of experiments that tried to infer the mechanisms from the observations that we were able to take in the existing experiment; these lines of evidence pointed to the fact that there was another mineral nutrient, another kind of fertilizer, that was required for plant growth that was preventing them from taking advantage of the elevated atmospheric CO2 and it might even be becoming less available under elevated CO2. But we couldn’t be sure unless we did a separate experiment. The evidence suggested that this limiting resource was probably phosphorus.


There you have it. The experiment confirms the principle of limiting factors. At present concentrations, rising CO2 always increases plant productivity unless another factor is sub-optimal and constrains growth. The researchers, aided and abetted by the media are spinning this to say more CO2 is not good for plants. In reality, the lack of phosphorus or other nutrients is not the fault of CO2, and will not be enhanced by somehow reducing CO2.

Dr. Wittwer’s conclusion stands: Rising CO2 is Great for Plants.


Crabs really love CO2 as well.

Adapting Works! Mitigating Fails.


Two schools of thought regarding future climates:
Adaptation: As changes occur, adapt our methods and practices to survive and prosper in new conditions.
Mitigation: Cut down on use of fossil fuels to mitigate or prevent future global warming.

The Paris Agreement and various cap-and-trade schemes intend to Mitigate future warming. Lots of gloom and doom is projected (forecast) by activists claiming mitigation is the only way. But the facts of our experience say otherwise.

What has been human experience with Adapting to climate change?

Feeding ourselves is the most fundamental social need, so we should look at the history of Agriculture and climate change. Here is a data-rich study:
Adapting North American wheat production to climatic challenges, 1839–2009, by Alan L. Olmstead and Paul W. Rhodes Accessed at PNAS (here).

Numerous researchers have speculated about how farmers might change cultivars, cropping patterns, and farming methods to mitigate some of the costs of abrupt climatic changes (8). Researchers at the International Maize and Wheat Improvement Center (CIMMYT) anticipate that North American wheat farmers may extend the margin of wheat production roughly 1,000 km north into northern Canada and Alaska, whereas heat and drought will make cultivation untenable in many areas of the southern Great Plains (9). To provide perspective on these and other predictions, this paper asks how farmers responded to past climatic challenges.

The spread of wheat cultivation across North America required that farmers repeatedly adapt to unfamiliar and hostile climatic conditions. The variations in climatic conditions that settlers encountered rivaled the magnitude of the predicted changes at given locations over the next century. We quantify the extent of the geographic variations and decipher how wheat growers learned to produce in new environments. Because of the paucity of Mexican data before 1929, most of our analysis of “North America” refers to Canada and the United States. Inclusion of Mexico in the later part of the 20th century highlights the role of the Green Revolution in pushing production into hotter and drier zones. (my bolds)

Because of climate change, some areas presumably will decrease or cease wheat production, whereas other areas, particularly in northern Canada and Alaska, are expected to enter production. Although the anticipated movement in the wheat frontier is substantial, it is unlikely to be as great as the past geographic shifts in production. The difficulties in extending the transportation infrastructure to facilitate future shifts also appear less imposing than those overcome to open the Plains and Prairies. The challenging problems deal with adapting growing practices and creating improved cultivars. (my bold)


Shift in the North American spring–winter wheat frontier, 1869–1929.

The last two columns of the table, which show the differences between the Columbus baseline and the other four locations, illustrate the wide array of climatic conditions to which wheat has been adapted in North America during the past 170 y. Even with the predicted annual mean temperature by 2100, farmers near Edmonton, AB, and Dickerson, ND, will confront substantially colder conditions than eastern wheat growers faced circa 1839. Even with the anticipated increase in precipitation, the northern farmers will have to make do with about half the precipitation that the earlier generation of eastern farmers received. The predicted changes in Dodge City, KS, and Ciudad Obregón, Sonora, Mexico, suggest both hotter and drier conditions than were common at the center of North American production in 1839 (again, a climate akin to that in Columbus, OH, in the baseline period). Note, however, that the difference in temperature between Columbus and Ciudad Obregón was roughly six times the increase predicted in the latter city by 2100. Wheat production is sensitive to seasonal fluctuations in weather conditions, which probably will become more variable in the future and which are not captured by annual mean data (29). Nevertheless, the historical record of adapting wheat cultivation to areas with widely varying climates is impressive. (my bold)

For the most part, the settlement process required adapting cultivation to colder and more arid regions, not to hotter climates as predicted in the future. Farming with less water is more of a problem if the temperature also is hotter. However, biological innovations also were crucial to the expansion of production in hot-arid areas such as Texas, Oklahoma, central California, and northern Mexico. The currently predicted changes during the next century will, in a sense, reverse the predominant historical path of the past two centuries by creating a warmer and wetter environment in the Plains and Prairies that will partially approach the conditions that existed in the Middle Atlantic region when it constituted the North American wheat belt. (my bold)

The historical record offers insight into the capability of agriculture to adapt to climatic challenges. Using a new county-level dataset on wheat production and climate norms, we show that during the 19th and 20th centuries North American grain farmers pushed wheat production into environments once considered too arid, too variable, and too harsh to cultivate. As summary measures, the median annual precipitation norm of the 2007 distribution of North American wheat production was one-half that of the 1839 distribution, and the median annual temperature norm was 3.7 °C lower. This shift, which occurred mostly before 1929, required new biological technologies. The Green Revolution associated with the pioneering work of Norman Borlaug represented an important advance in this longer process of biological innovation. However, well before the Green Revolution, generations of North American farmers overcame significant climatic challenges. (my bold)

How successful has mitigation been?

A recent report of California’s cap-and-trade concluded:

The problem is that the permits are selling at a slower and slower rate. The surplus of allowances is becoming so large in systems run by Europe, California and Quebec — which together account for more than 90 percent of global trading — that by 2022 it could cover the emissions spewing from every car on Earth for a full year, according to estimates by the London environmental group Sandbag Climate Campaign CIC and Bloomberg New Energy Finance.

In California’s market, all 23 million allowances sold in an auction in 2014. In May 2016, 7.3 million permits found buyers, only 11 percent of what was put up for sale.

ReGGI, the carbon market joined by Northeastern US states is also ineffective but has the potential to threaten affordable electricity there. See my post: Cap and Trade Hype

Even more telling is the recent revolt by Democrat politicians against the way California distributes proceeds from auctions of carbon credits. From the LA Times: A big question complicating the climate debate: Where’s the money for poor people?

Unless more money gets directed to poor communities, lawmakers whose votes may be needed to continue the climate change efforts say they’re wary. Assemblyman Jim Cooper (D-Elk Grove), a leader in the business-aligned bloc of his party, said he hasn’t made up his mind, in part, because he’s outraged that people living in a handful of wealthy Bay Area and West Los Angeles communities have received by far the largest shares of state rebates to purchase electric cars.

“It’s welfare for the rich,” Cooper said. “It’s dead wrong in my book. It should be wrong in anybody’s book.”

Inadvertently, they are scraping the lipstick off the Mitigation Pig. They know (but don’t say out loud) this scheme does little to lower fossil fuels, and has even less impact on future climates. But it does create a pot of money, and they want the poor to have their share. If you are going to redistribute wealth, at least transfer it from the rich to the poor, as Robin Hood did. Mitigation is failing in every imaginable way.


Farmers have successfully grown and harvested crops in places formerly deemed too cold or too arid, and most of the new fields were in the North. Remarkably, today’s average climate where wheat is produced is both drier and colder:
“The median annual precipitation norm of the 2007 distribution of North American wheat production was one-half that of the 1839 distribution, and the median annual temperature norm was 3.7 °C lower.”

Agriculture has demonstrated our massive capacity to adapt to changing conditions, whether it becomes warmer or cooler, wetter or drier.

The rational climate change policy has been proven successful: Don’t Fight It, Adapt.


Bumper crops expected
Grain companies predict near-record western harvest
Source: The Western Producer

The 2016 harvest is shaping up to be a whopper, according to Western Canada’s largest elevator companies.