Climate Change and Global Food Availability
A new study by NASA climate scientist James Hansen to be published on Monday in the Proceedings of the National Academy of Sciences directly connects global climate change with the spate of extreme weather events in the recent past. In what should be a “duh” moment for most observers, Hansen argues that, “the climate dice are loaded.” In an accompanying editorial in the Washington Post, Hansen argues,
The deadly European heat wave of 2003, the fiery Russian heat wave of 2010 and catastrophic droughts in Texas and Oklahoma last year can each be attributed to climate change. And once the data are gathered in a few weeks’ time, it’s likely that the same will be true for the extremely hot summer the United States is suffering through right now… This is the world we have changed, and now we have to live in it — the world that caused the 2003 heat wave in Europe that killed more than 50,000 people and the 2011 drought in Texas that caused more than $5 billion in damage. Such events, our data show, will become even more frequent and more severe.
Hansen’s conclusions are important not because they present new material or findings, but because they represent one of the first times scientists are directly connecting extreme weather events with climate change. Historically, climate change scientists couched their conclusions with caveats noting that specific events cannot be connected to broad climate change trends. Andrew Weaver of the University of British Columbia emphasized the importance of this shift, nothing that Hansen’s study shifts our thinking. “Rather than say, ‘Is this because of climate change?’ That’s the wrong question. What you can say is, ‘How likely is this to have occurred with the absence of global warming?’ It’s so extraordinarily unlikely that it has to be due to global warming.”
From the perspective of global food politics, Hansen’s study provides an important warning. We already know that fallout from global climate change will be unevenly distributed, with the global south suffering a disproportionate share of the negative impacts. William Cline’s 2007 analysis noted demonstrated that parts of the global south—especially parts of Africa—could see crop yields decline by between 25 and 50 percent (see figure below) as they experience hotter weather and more erratic rainfall.
In short, the current “worst drought in a generation” is increasingly likely to be the “worst drought since last year’s drought.” We need to start thinking about these questions now.