It’s hard to read about climate change. By that, I mean it’s literally difficult to decipher the latest summary from the Intergovernmental Panel on Climate Change (IPCC). The IPCC is the international body set up in 1988 to assess the evidence, impacts, and future risks of climate change. Its latest report focuses on impacts, adaptation, and vulnerability, a topic it would behoove us all to understand better.
The executive summary, made public today in Yokohama, Japan, is a slog to read, as one might expect of a document that lists 70 “drafting authors,” but the message is pretty clear: The effects of climate change are already being felt everywhere, and no one will remain untouched. Here are five key points:
1. Climate change is already having a negative impact on wheat and corn yields. While some colder climes may benefit in higher yields as they warm, overall crop yields for wheat, rice, and corn are likely to fall, and to vary more widely year to year, because of rising temperatures, even as demand rises rapidly.
2. Deaths related to heat have increased, and deaths related to cold have decreased as a result of warming. The report mentions heat-related deaths as one of the key risks for North America and Asia.
3. For North America, the other big risks highlighted in the report are: deaths, property loss, and ecosystem damage from wildfires; flooding in urban areas on coasts and near rivers that will lead to property and infrastructure damage; and lower water quality related to a rise in sea levels, extreme precipitation, and cyclones.
4. Fisheries are likely to get redistributed as the oceans warm. Tropical countries are expected to experience a drop in catches, hurting food security, income, and employment in affected countries. The worst-hit areas, clustered around the equator and also in polar regions, could see a decline in catch potential of more than 50 percent from 2051 to 2060, compared with the period from 2001 to 2010.
5. It’s hard to assess the future economic impact, but the report takes a stab, estimating that annual economic losses will be between 0.2 percent and 2 percent of global income for temperature increases of 2 degrees Celsius. That number doesn’t sound huge. The report points out that estimates depend on a large number of assumptions, and many don’t account for catastrophic changes and other factors.