The director of the United States Department of Agriculture's Climate Change Program said Wednesday that global warming will cause an increase in the number of "miserable days" over the next several years.
William Hohenstein said that the "misery index," a measure of temperature and humidity, will continue to get higher in many parts of the country, especially the southwest. He said the number of days with temperatures above100 degrees will increase. With it, farmers might face increasingly difficult conditions.
"As that index gets higher and higher, you see reductions in production and then you see mortality [in farm animals]," he said at Washington, D.C.'s Wilson Center during a discussion on climate change's impacts on public health and agriculture.
Last year was the hottest year on record in the contiguous United States, according to NOAA. The average temperature of 55.3 degrees was a degree warmer than the previous record in 1998 and 3.2 degrees higher than the average temperatures during the 1900s.
Much of the United States was hit with abnormally dry conditions as drought cost more than $35 billion in lost crops and killed more than 100 people, according to insurance broker AON Benfield.
Hohenstein said that while there have been similar droughts in other years and it is impossible to say whether the drought and heat wave would have occurred without climate change, global warming is a likely culprit.
"What's important is climate change is happening and it underpins everything going on in the climate system," he said. "The changes we saw last year are consistent with what we'd expect under climate change."
While climate scientists are all but certain that global warming is happening, Hohenstein says that for individual farmers, planning for the future is more difficult. Many global and even country-specific models for climate change based on certain carbon emissions have been created, but narrowing that down to a more local level is difficult.
"Farmers exist in a very local environment. We can't tell them how [climate] will change in this county in Michigan or this county in Iowa because the risks are disproportionate," he said. "But it certainly is happening. It's in the data and we're going to be affected in a variety of ways."