- Climate
Analysis of "…in many ways global warming will be a good thing"
Scientists’ Feedback
SUMMARY
Bjorn Lomborg’s article in The Telegraph argues that “global warming causes about as much damage as benefits”, in blatant disagreement with available scientific evidence, while the author does not offer adequate evidence to support his statements. Upon inspection of the references cited by Lomborg, it turns out that he misrepresents the studies he cites according to their authors (in violation of the Society of Professional Journalists Code of Ethics).
While Lomborg argues in favor of more balanced climate reporting, the scientists who have reviewed this article conclude Lomborg himself fails to balance the available evidence that adverse impacts of climate change overwhelm the positive ones.
See all the scientists’ annotations in context
GUEST COMMENTS
Professor, Met Office Hadley Centre & University of Exeter
Lomborg cites the Cramer et al study, on which I was a co-author, in support of the “good news” that rising CO2 is greening the planet. While this is true at the moment, Lomborg fails to point out the main result of the Cramer et al study, which is that the greening effect of CO2 is projected to show diminishing returns as CO2 continues to increase, while the negative impact of climate change itself continues to increase. Indeed the study projected a decline in tropical net primary productivity after 2050. I’ve not had chance to check the sources for the rest of his article, but if he’s prepared to spin one paper to give the opposite impression to its actual message, is he doing this with others?
REVIEWERS’ OVERALL FEEDBACK
These comments are the overall opinion of scientists on the article, they are substantiated by their knowledge in the field and by the content of the analysis in the annotations on the article.
Senior researcher, CIRED, Ecole des Ponts
The claim that economic benefits are balancing economic losses from climate change, at the global level, is not supported by existing estimates.
Professor, University of Exeter
This article presents a highly biased view of global warming, only presenting the “positive” aspects of it. As the author is criticizing media for doing the opposite (always showing the bad side of climate change) it is a shame the author didn’t present a balanced view here.
CNRS Research Director, Université Pierre et Marie Curie & Professor, University of Reading
This piece misleads its readers into thinking positive impacts of climate change could outweigh the negative impacts but are “never discussed”. It ignores the large amount of research that shows that negative impacts by far outweigh the positive, as summarised in the IPCC reports. It is not very difficult to understand that a fast and large disruption of our environment is bound to have large socio-economic negative impacts.
Research Scientist, University of Colorado, Boulder
The article cites many excellent sources, but fails to accurately represent the information they contain.
Research Associate, Harvard University
Lomborg appears guilty of the very thing he accuses others of doing: focusing too much on one side of the story (the positive impacts of climate change, here). He’s right that a comprehensive assessment of climate change impacts is needed, but that’s precisely what the IPCC already does.
Associate Professor, University of Utah
Significant inaccuracies and cherry picking.
Researcher, Royal Netherlands Institute for Sea Research (NIOZ)
Contrary to the author’s claim, IPCC is not denying that there can be some benefits to global warming, but the literature overwhelmingly indicates that the bad is not outweighed by the good. Upon further inspection of the literature cited it turns out that some of the numbers are conveniently picked and do not tell the whole story.
Climate Scientist, Environmental Defense Fund
The scientific information itself is not egregiously wrong, however the interpretation of the information is. The author misleads the audience with flawed logic, omission of important information, and cherry-picked examples.
Physical Oceanographer, University of Tasmania
Most of the scientific work cited in this article has been either misrepresented or cherry-picked to fit the story the author wants to tell.
Founder & Executive Director, Science Feedback
The piece is particularly misleading as it might sound reasonable and balanced to someone who has no knowledge of climate change, but a careful inspection reveals that the author does not back his claims with appropriate supporting evidence and commits the cherry-picking he is accusing everybody else of.
Notes:
[1] See the rating guidelines used for article evaluations.
[2] Each evaluation is independent. Scientists’ comments are all published at the same time.
Key Take-aways
The statements quoted below are from Bjorn Lomborg; comments and replies are from the reviewers.
“global warming causes about as much damage as benefits.”
Senior researcher, CIRED, Ecole des Ponts
The studies of the aggregate economic impacts from global warming synthesized in the last IPCC (Intergovermental Panel on Climate Change) do not support the claim that benefits from climate change counterbalance the costs. All but one study find net costs, and the study finding aggregate benefits at the global level is focusing on a very low warming (+1°C). Since the IPCC assessment report, new studies have evaluated economic costs and benefits from climate change. Notably, Burke et al 2015 (Global non-linear effect of temperature on economic production) do find some net benefits for a limited number of countries, but at the global level the net economic effect corresponds to costs.
Professor, University of Exeter
This claim is not supported by any source. Read the IPCC synthesis report Summary for Policy-Makers (SPM) headlines for a balanced assessment: “Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems.” …
“we should look at all the available information.”
Professor, University of Exeter
Yes indeed, this is exactly what the IPCC does. I agree with Lomborg that having unbalanced views, only showing negative outcomes, is not helpful. But this is also true for this article that attempts to only show positive outcomes. Planet will get greener, less people will die in winter, the developed world is less vulnerable, precipitation will increase … All of these statements are severely biased, only telling half of the story (if not less…).
“If our climate conversation managed to include the good along with the bad, we would have a much better understanding of our options.”
Professor, University of Exeter
True, but the author should set the example and have a balanced view here, showing the bad along with the good. Something he dramatically failed to do.
“Any reasonable person can recognize both positives and negatives among the policy proposals of both Tories and Labour.”
Research Associate, Harvard University
Lomborg seems to imply here that the assessment of the impacts of climate change should follow the same “balance” with which we consider political ideas. But the assessment of the global impacts of climate change is something scientific in nature. It’s not a matter of values or preferences, like political leaning. All things considered, it just so happens, as the IPCC points out, that the global impacts of climate change appear negative.
“Over time, climate becomes a net problem: by the 2070s, the UN Climate Panel finds that global warming will likely cause damage equivalent to 0.2 per cent to 2 per cent of global GDP.”
Research Associate, Harvard University
While a costs/benefits analysis of the impacts of climate change is certainly informative, we have to keep in mind that we probably cannot evaluate very well all the future costs associated with it, e.g., rising sea levels, ecosystems shifts, changes in water resources, etc. The numbers cited by Lomborg are thus likely conservative, and reflective of modest climate change (~2C). This is what the IPCC report Lomborg cites actually says: “…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) (medium evidence, medium agreement). Losses are more likely than not to be greater, rather than smaller, than this range (limited evidence, high agreement)…” [read more]
“Because CO₂ acts as a fertilizer, as much as half of all vegetated land is persistently greener today. This ought to be a cause for great joy.”
Research Associate, Harvard University
The Nature study quoted provides nice evidence of the CO2 fertilization effect on global ecosystems, but as the author notes further down, it doesn’t really come as a surprise, if anything because we know that the land is absorbing about a quarter of human CO2 emissions (if this wasn’t happening atmospheric CO2 would be increasing even faster than it is now). So it is consistent with the land currently acting as a carbon sink; now the question really is, what happens to this land carbon sink as we go forward? The CO2 fertilization effect can be expected to level off, in particular as other nutrients become limiting for plant growth (nitrogen, phosphorus), whereas the effects of climate change will increase, with warmer temperatures and more intense water stress likely leading to more ecosystem carbon loss. Overall, when considering all the relevant science – something the IPCC does, but Lomborg fails to do here – the future of the land carbon sink under the combined effects of increased CO2 and climate change, remains highly uncertain – certainly not as rosy as Lomborg implies in this article.
Professor, University of East Anglia, and Director of Research, Climatic Research Unit
The impression given by this statement is that CO2 fertilisation of vegetation growth outweighs all the adverse impacts of climate change. Joy or concern should be based upon an assessment of all the impacts and not just on one aspect, as done here. Comprehensive assessments (e.g. IPCC WG2) consistently find climate change to be a cause for much concern, not for “much joy”, as claimed by the author.
Climate Scientist, Environmental Defense Fund
This is a naive statement because scientists have found that although higher concentrations of CO2 stimulate carbohydrate production and plant growth, they also deplete plants of nutrition through lowering the levels of protein and essential minerals. This impacts animal species’ food sources as well as a number of widely consumed crops, such as wheat, rice, and potatoes, which could greatly impact human health. (Loladze, 2014)
“precipitation from global warming will make the world much greener”
Associate Professor, University of Utah
This is highly uncertain. The CO2 and precipitation trends will also be accompanied by increasing temperatures and increasing drought, which is likely to harm vegetation. The balance of these factors is still unclear.
“global warming will make the world much greener – by the end of the century, it is likely that global biomass will have increased by forty percent.”
Associate Professor, University of Utah
This is an inaccurate description of the science. The future of global biomass and the land carbon sink is highly uncertain and spans anywhere from a large increase to a large loss of biomass. The paper cited is wildly out of date (from 2001) and models have progressed immensely since then. Furthermore, there is growing evidence that even these more recent models are over-optimistic (e.g. Allen et al 2015)
Professor, Directeur de Recherche, Mediterranean Institute for Biodiversity and Ecology (IMBE)
Actually, this statement of Lomborg correctly cites our study from 2001, […] The problem is that CO2-driven biomass growth in itself does not represent good news: for many agricultural crops, for example, the direct effects of high temperatures will outweigh the growth benefits eventually, notably for spring wheat and soybean. These aspects are discussed, in a well-balanced way, by the latest IPCC report, citing numerous references.
“We have known for decades that increasing CO₂ and precipitation from global warming will make the world much greener – by the end of the century, it is likely that global biomass will have increased by forty percent.”
Professor, University of Exeter
In short, the negative effect of climate change is expected to largely offset the positive effect of increasing CO2. [read more]
“A recent Nature study expecting more severe hurricanes from global warming still found that damages would halve from 0.04 per cent to 0.02 per cent of global GDP, because the increased ferocity would be more than made up by increased prosperity and resilience.”
Professor of Atmospheric Science, MIT
According to the Nature Climate Change study, “Climate change is expected to cause global tropical cyclone damage to increase by US$53 billion per year” by 2100. Although it is true that Gross World Product (GWP) is expected to rise faster, it does not necessarily do so in the same places that storm damage increases. There is much uncertainty in both the tropical cyclone projections (discussed in the Nature Climate Change paper) and in GWP projections, but in any case, increasing damage from tropical cyclones is nothing to celebrate.
“Yet, a new study of 60 climate models and scenarios shows this warning fails to take into account the fact that global warming will mean precipitation increases. Indeed, water flow will actually increase over this century, which is likely beneficial in increasing “water availability in the Indus Basin irrigation scheme during the spring growing seasons.” ”
PhD Candidate, Future Water & Utrecht University
The cited study states that runoff in the Indus basin will increase during the first half of the 21st century, mainly due to increasing glacier melt (not precipitation increase as mentioned here). This increase in flow from glacier melt is projected to decrease during the 2nd half of the 21st century (Immerzeel et al, 2013: Rising river flows throughout the twenty-first century in two Himalayan glacierized watersheds). … Besides, an increase in frequency and magnitude of hydrological extremes (flooding events) is projected. [read more]
Research Scientist, University of Colorado, Boulder
The issue of drinking water availability is more nuanced than either extreme represented here. Increases in glacier melt can have a wide range of impacts depending on the location and timing of the change. For example, complete loss of an alpine glacier that is used for summer drinking water can result in dramatic water shortages for those communities. On the other hand, increasing glacier melt can mean short term (decades) increases in river water – such as for the upper Indus basin noted in this study. Unfortunately, increased water availability from glacier loss is bound to end once those glaciers disappear.
“What we don’t hear from her is that fewer people will die from cold.”
Climate Scientist, Environmental Defense Fund
Every report I have ever read about the impacts of climate change on temperature-related deaths discuss both the impacts of heat and cold. Such as the new USGCRP Health report:
“Based on present-day sensitivity to heat, an increase of thousands to tens of thousands of premature heat-related deaths in the summer [Very Likely, High Confidence] and a decrease of premature cold-related deaths in the winter [Very Likely, Medium Confidence] are projected each year as a result of climate change by the end of the century. Future adaptation will very likely reduce these impacts (see Changing Tolerance to Extreme Heat Finding). The reduction in cold-related deaths is projected to be smaller than the increase in heat-related deaths in most regions [Likely, Medium Confidence].”
Climate Feedback:
This claim is not supported by available evidence and has been thoroughly discussed in a previous Climate Feedback analysis of an op-ed by Bjorn Lomborg.
For instance, Aaron Bernstein, Associate Director of the Center for Health and the Global Environment at Harvard commented:
“While it’s true that cold may kill more people today than heat, Lomborg’s assertion that climate change will result in fewer overall deaths in the U.S. this century from extreme temperatures is not supported by available evidence.”
“No one ever says it, but in many ways global warming will be a good thing”
Professor, University of East Anglia, and Director of Research, Climatic Research Unit
The title is inaccurate. The IPCC, for example, a leading and authoritative source of climate change information, includes benefits as well as adverse effects in its assessment. Even the second sentence of its Working Group 2 Summary for Policymakers (SPM) notes that there are potential benefits, and some of these are covered in the remainder of the SPM. While the author may feel that the balance isn’t right, it is inaccurate to say that the potential benefits are never stated.
Professor, University of Exeter
There are many blogs that also claim that “global warming will be a good thing”… However, when it comes to robust, reviewed and assessed science, as done by IPCC, global warming will not be a good thing… It will have positive effects in some regions, but also negative effects in others. The overall balance is getting predominantly negative with increased level of warming. Read IPCC 5th Assessment report, Summary for Policymakers from Working Group 1 and Working Group 2.
“in a letter to The Times from Lord Krebs and company, essentially telling the newspaper to stop reporting less-than-negative climate stories.”
Founder & Executive Director, Science Feedback
This is a misrepresentation of the Lords’ letter. The letter builds on scientists’ analyses of two inaccurate articles on climate change in The Times, and it asks the editor to center their coverage on the facts rather than on the viewpoints of a marginal pressure group.
Misrepresenting someone’s position to make it easier to attack is known as a straw man fallacy.
