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Climate and the Media I
Treatment of climate in the IPCC reports, especially in the summary for policy makers, is biased but, so far as I can tell, honest. Unfortunately, few people actually read the IPCC report and those who do mostly read only the summary for policy makers, which in my experience is the most biased and least scientific part of the report. Most people get their views on climate issues at second hand from news stories, blogs, YouTube channels, friends and acquaintances. Most reporters do not understand the issues and even climate scientists are unlikely to understand other subjects that feed into views on climate, such as economics, geology, or statistics. The result is that most people’s beliefs about climate issues have only a loose relation with the truth.
The major media and the academy are dominated by people who, in my view, overestimate the problem, so the most common errors are in that direction. There may be equally bad errors in the views of some on the other side of the argument but those are not the subject of this post.
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Media vs IPCC
I started blogging in 2005, first discussed climate in 2006. In the years since I have been repeatedly struck by the contrast between the IPCC reports and media accounts of them, starting with the Fourth Assessment report in 2007.
The Fourth Assessment Report
From a news story:
Climate change is "severe and so sweeping that only urgent, global action" can head it off, a United Nations scientific panel said in a report on global warming issued Saturday.
The report produced by the Nobel prize-winning panel warns of the devastating impact for developing countries and the threat of species extinction posed by the climate crisis.
The report also predicts a rise in global warming of around 0.2 degrees Celsius per decade."
"Nobel prize-winning" sounds like evidence of scientific expertise but although the IPCC includes a lot of highly qualified scientists, the fact that the commission got the Nobel peace prize tells us nothing about its scientific qualifications. Al Gore got the peace prize too, and he is a politician not a scientist.
The emotive part of the story — "crisis" "species extinction" "devastating impact" — comes first and gets the attention. The actual prediction, an increase of less than two degrees by the end of the century, not what most people imagine when they talk about global warming, is buried down in "also predicts."
From the IPCC, in contrast:
Globally, the potential for food production is expected to increase with increases in average temperature over a range of 1-3 degrees centigrade, but above this it is projected to decrease.1
Or in other words, given what was then the predicted temperature increase of about .2 degrees/decade, global warming was expected to increase food production for the next fifty to hundred and fifty years. I did not notice that prediction in news stories about the report.
Globally, commercial timber productivity rises modestly with climate change in the short- to medium-term, ... 2
In some cases the problem is with the wording of the report itself:
Nearly all European regions are anticipated to be negatively affected by some future impacts of climate change, ... .3
Note the word "some." It is hard to imagine any substantial change in the world, good or bad, for which the statement would not be true. If, for example, we found a cure for cancer, one effect would be to extend life expectancies, pushing the social security system further into the red, another to reduce job opportunities for cancer surgeons.
The IPCC predicted global temperature increases of 1.8 to 4 degrees Celsius (3.2 to 7.1 degrees Fahrenheit) by 2100 and sea levels to rise between 7 and 23 inches (18 and 58 centimeters) by the end of the century. ...
Talk about the danger of rising sea levels, at least in my experience, is usually accompanied by verbal or visual images of Florida flooding, Manhattan and London under water, and similar catastrophes. If the IPCC figures were correct, the upper end of the range of what might actually happen was a rise of less than a meter over a century, considerably less than the distance between high tide and low.5 Consider, for one example, a picture of the National Mall in DC flooded with 3°C warming. In the small print at the bottom: “these sea levels may take hundreds of years to be fully realized.”
The picture below was supposed to show New York after eight feet of rise.
The next image is New York from the flood maps page showing how much of Manhattan is within three meters, about ten feet, of sea level
For another example:
No one seems to care about the upcoming attack on the World Trade Center site. Why? Because it won’t involve villains with box cutters. Instead, it will involve melting ice sheets that swell the oceans and turn that particular block of lower Manhattan into an aquarium.
The odds of this happening in the next few decades are better than the odds that a disgruntled Saudi will sneak onto an airplane and detonate a shoe bomb. And yet our government will spend billions of dollars this year to prevent global terrorism and … well, essentially nothing to prevent global warming. (Dan Gilbert, Los Angeles Times, July 2, 2006)
The sixth IPCC report projects, for the high emissions scenarios, sea level rise by 2300 of from two to seven meters. The World Trade Center site is 12 meters above sea level.
Popular talk about warming, again in my experience, is usually put in terms more apocalyptic than the IPCC's upper estimate of four degrees Celsius by 2100, roughly the current difference between Wisconsin and Ohio. No newspaper I saw at the time headlined its story on the fourth report with "Global Warming a Wet Firecracker, International Panel finds temperature and sea level effects over the next century real but small."
2014: The Fifth Assessment Report
Anthropogenic warming remains a relatively small contributor to the overall magnitude of any individual short-term event because its magnitude is small relative to natural random weather variability on short time scales. Because of this random variability, weather events continue to occur that have been made less likely by human influence on climate, such as extreme winter cold events ...6
Contrast the final sentence to occasional claims that recent unusual cold is evidence for, not against, climate change.7
While only a few recent species extinctions have been attributed as yet to climate change (high confidence), natural global climate change at rates slower than current anthropogenic climate change caused significant ecosystem shifts and species extinctions during the past millions of years.8
Warnings about large numbers of species being driven to extinction by anthropogenic climate change9 have morphed into the observation that species have gone extinct in the past over very long time periods for reasons unrelated to human action.
Some low-lying developing countries and small island states are expected to face very high impacts that, in some cases, could have associated damage and adaptation costs of several percentage points of GDP.10
Compare costs of several percentage points of GDP in the places most at risk due to sea level rise with the rhetoric of hundreds of millions of climate refugees, drowned island chains, and the like. For two more passages that contradicted the popular view:
There is no evidence that surface water and groundwater drought frequency has changed over the last few decades, although impacts of drought have increased mostly due to increased water demand.11
Economic losses due to extreme weather events have increased globally, mostly due to increase in wealth and exposure, with a possible influence of climate change (low confidence in attribution to climate change).12 (p. 982, op. cit.)
I have been contrasting the contents of the IPCC reports to popular views of the dangers of climate change. The problem is mostly the fault of the media but the IPCC, in particular the Summary for Policy Makers that accompanies each report, sometimes encourages a misreading of the scientific results in the alarmist direction not by what they say so much as by how they say it.
Climate change has negatively affected wheat and maize yields for many regions and in the global aggregate (medium confidence). Effects on rice and soybean yield have been smaller in major production regions and globally, with a median change of zero across all available data …13
That does not say that yields have fallen, although that is what a careless reader is likely to think, only that they are lower in some areas than they would have been without climate change. A little searching finds a scholarly article on wheat yields from 2012 which reported that
Wheat yields have increased approximately linearly since the mid-twentieth century across the globe, but stagnation of these trends has now been suggested for several nations. .... With the major exception of India, the majority of leveling in wheat yields occurs within developed nations—including the United Kingdom, France and Germany—whose policies appear to have disincentivized yield increases relative to other objectives. The effects of climate change and of yields nearing their maximum potential may also be important....
Near the time that leveling is generally observed, the European Union shifted away from a policy that rewarded high agricultural production through price guarantees to a policy that pays flat subsidies that do not increase with production and triggers taxes when production limits are exceeded
What has happened is not that yields have decreased but that in some areas they have stopped increasing, at least in part due to changes in agricultural policy.
At present the world-wide burden of human ill-health from climate change is relatively small compared with effects of other stressors and is not well quantified. However, there has been increased heat-related mortality and decreased cold-related mortality in some regions as a result of warming ... .14
The first sentence makes it sound as though climate change is making things worse. The second implies that there have been both costs and benefits and offers no estimate of their relative size.
People who are socially, economically, culturally, politically, institutionally, or otherwise marginalized are especially vulnerable to climate change.15
That is designed to imply that preventing climate change is particularly important because the victims are people we feel sympathy for but also implies that pressuring poor countries to produce less energy or produce it in ways that produce less CO2 but are more expensive might decrease the amount of climate change but, by keeping them poor, increase the damage it does.
Impacts from recent climate-related extremes, such as heat waves, droughts, floods, cyclones, and wildfires, reveal significant vulnerability and exposure of some ecosystems and many human systems to current climate variability.16
Climate-related extremes are not limited to those due to climate change. Floods, cyclones, et. al. do damage...and always have.
For the major crops (wheat, rice, and maize) in tropical and temperate regions, climate change without adaptation is projected to negatively impact production for local temperature increases of 2°C or more above late-20th-century levels, ...17
Emphasis mine. If farmers ignore the implications of climate change for what crops they should grow and how to grow them and continue to ignore them for the next sixty years or so, output is expected to decline. I discussed the point at greater length in Climate Change and Food Supply.
With these recognized limitations, the incomplete estimates of global annual economic losses for additional temperature increases of ~2°C are between 0.2 and 2.0% of income (±1 standard deviation around the mean)[18
Increase of global mean surface temperatures for 2081–2100 relative to 1986–2005 is projected to likely be in the ranges derived from the concentration-driven CMIP5 model simulations, that is, 0.3°C to 1.7°C (RCP2.6), 1.1°C to 2.6°C (RCP4.5), 1.4°C to 3.1°C (RCP6.0), 2.6°C to 4.8°C (RCP8.5).[19
The report is from 2014, by which time global temperatures were higher than the 1986-2005 average by about .31°C. Reducing the figures in the second paragraph by that to fit the “additional temperature increases” of the first paragraph, it implied that we were unlikely to experience much more than 2°C of additional warming by 2100 in any but RCP8.5, originally proposed as an upper bound on how bad climate change could be.20 If policies to prevent warming reduced the annual growth rate of world income from (say) 2% to 1.98%, the resulting loss would just about cancel the gain. Not a compelling argument for switching from fossil fuels to solar power.
Parry et. al. Op. Cit. p. 12
Parry et. al. Op. Cit. p. 14
As I write this, the latest projection, from the sixth report, shows likely sea level rise by the end of the century as under 1 meter, with a “Low-likelihood, high-impact storyline, combined with the highest emissions scenario, pushing that up to about 1.75 meters.
Stocker, T.F. et. al., IPCC, 2013: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, Chapter 10, p. 916.
RCP8.5, sometimes misleadingly described as “business as usual,” was originally designed as an upper bound on how bad climate change might be if everything that could went wrong.