Jon Proctor, Solomon Hsiang, and coauthors published a study in Nature estimating the effect of solar radiation management (SRM) on global agricultural production. The paper exploits the historical eruption of massive volcanoes that inject sulfate aerosols into the stratosphere to understand the effect of changing light conditions on crop yields. The paper finds that benefits from cooling, the intended effect of SRM, are fully offset by harm to yields via shading.
Read the study ungated here.
A resource page for the article is here.
Press release here.
Greg Ip discussed our research into the global economic costs of excess mortality risk caused by climate change in his recent Wall Street Journal column.
The research covered in the article is output from the Climate Impact Lab, a collaboration between the GPL at Berkeley, EPIC at U Chicago, The Rutgers Earth System Science & Policy Lab, and the Rhodium Group.
Solomon Hsiang spoke about methods used value the climate at the Sackler Colloquia on Economics, Environment, and Sustainable Development, organized by Simon Levin, Stephen Carpenter, Gretchen Daily, Sir Partha Dasgupta, Paul Ehrlich, Geoffrey Heal, Catherine Kling, Jane Lubchenco, and Stephen Polasky.
Joshua Graff Zivin, Matthew Neidell and Sol Hsiang published a new article "Temperature and human capital in the short and long run". Analyzing over 24,000 student exams and following individual students over time, they demonstrate that cognitive performance in mathematics declines at high temperatures, but not in reading or verbal exams.
Read the article here.
Tatyana Deryugina and Solomon Hsiang have a new NBER working paper out titled "The Marginal Product of Climate". The analysis develops a formal theory for how overall economic productivity due to the climate should be valued, accounting for the fact that populations adapt to changes in their climate. They apply their approach to data on the United States and estimate that "business as usual" warming is worth roughly $6.7 trillion in foregone production within the US market economy.
Read the paper here.
Solomon Hsiang gave a keynote at the World Congress of Science Journalists on the science of understanding the social effects of climate change and the role it may play on exacerbating future inequality. The keynote is followed by a 25 min Q+A with the audience of journalists.
Solomon Hsiang has a new joint paper with Paulina Oliva, and Reed Walker reviewing and exploring what is known about the distributional consequences of environmental damages and the benefits of environmental policy. They provide a general framework for empiricists and explore what is known in the context of pollution, deforestation, and climate. The NBER working paper is available online here. The article is forthcoming in the Review of Environmental Economics and Policy.
Tamma Carleton has a new paper out in PNAS linking the climate to suicide rates in India.
The analysis is the first to provide large-scale empirical evidence that the climate influences suicide rates in a developing country. The study shows that temperature during India's main agricultural growing season has a substantial influence over annual suicide rates, such that heating up the country by just 1 degree C on one day causes approximately 65 annual suicides. This effect appears to materialize through an agricultural channel in which high temperatures cause crop losses and economic distress, leading some to commit suicide in response. Carleton estimates that warming trends experienced in India since 1980 are responsible for a total of over 59,000 suicides.
See the paper here.
James Rising, Solomon Hsiang, and former lab member Amir Jina, along with other teammates from the Climate Impact Lab, have a new paper out in Science calculating economic damages from climate change in the United States.
The analysis is the first to construct a "damage function" using micro-level econometric results for a large number of sectors, linked to the full suite of climate models used in CMIP5. Because the analysis has high spatial resolution, it is able to resolve how impacts of unmitigated climate damages across the country will vary, demonstrating that it will substantially increase economic inequality.
Update: The team at the Associated Press did a really nice interactive visualization of the results:
Two big things happened today. First, our team at the Climate Impact Lab launched an interactive data visualization page where many of our results will be featured as we produce them. You can zoom to the future and see probabilistic outcomes at unprecedented resolution (>24,000 individual regions!).
Second, the New York Times featured the the Impact Lab's work and built their own visualization to illustrate the changing frequency of extremely hot days expected in the future.
In his recent Science article The Irreversible Momentum of Clean Energy, President Obama jumped into the "growth vs. levels" debate among empirical economists studying the effects of climate change, writing
[E]vidence is mounting that any economic strategy that ignores carbon pollution will impose tremendous costs to the global economy and will result in fewer jobs and less economic growth over the long term. Estimates of the economic damages from warming of 4°C over preindustrial levels range from 1% to 5% of global GDP each year by 2100 ... In addition, these estimates factor in economic damages but do not address the critical question of whether the underlying rate of economic growth (rather than just the level of GDP) is affected by climate change, so these studies could substantially understate the potential damage of climate change on the global macroeconomy (8, 9).
and citing the recent GPL paper on the global effects of temperature on growth.
Talk about a president who gets into the nuts and bolts...
James Rising has a new working paper Weather-driven adaptation in perennial crop systems:An integrated study of Brazilian coffee yields, demonstrating how farmers in Brazil cope with changing environmental conditions by altering the portfolio of coffee crops they maintain. The analysis develops a novel structural Bayesian modeling approach that embeds reduced form modeling estimates, allowing James to solve (for the first time) the well-known "problem with perennials", i.e. the fact that analysts and policy-makes cannot generally observe the number of long-live plants (perennials) that farmers maintain on a farm. The analysis is important because it demonstrates how farmers cope with a changing climate by changing their investment decisions, sometimes amplifying the economic impact of changes in climate.