Nonlinear Temperature Effects Indicate Severe Damages to U.S. Crop Yields Under Climate Change
It's been a long haul, but my coauthor Wolfram Schlenker and I have finally published our article with the title of this blog post in the Proceedings of the National Academy of Sciences . We've been told that it would show up on the early-edition website this week. It hasn't shown up there yet so I guess it will come out tomorrow [Friday 8/28], probably late afternoon EST. UPDATE: You can find the article here . We set out to develop a better statistical model linking weather and U.S. crop yields for corn, soybeans and cotton, the largest three crops in the U.S. in production value. Our major new finding is that (by far) the best predictor of yield is a measure of extreme heat: how much temperatures exceed about 29C (84F) during the growing season. The threshold varies somewhat by crop--29C is the threshold for corn. Below this threshold, warmer temperatures are more beneficial for yields, but the damaging effects of temperatures much above 29C are staggeringly large. A
high mins outumber new highs 3 to 1:
ReplyDeletehttp://mapcenter.hamweather.com/records/7day/us.html?c=maxtemp,highmin
I found this by Stu Ostro, "The ridge, heat, humidity, drought, and Dust Bowl"
ReplyDeletehttp://www.weather.com/blog/weather/8_25097.html
to be a good description of what is happening in U.S. weather right now.
As the writer states, comparing our current heat wave to heat in the 1930s, and given the context of climate change:
"What happened in the 1930s and other decades reinforces that there have always been extremes in weather, and there is always natural variability at play. What's changing now is the nature of those extremes, and also what's important is the context."
"This time, the extreme drought, heat, and wildfires are occurring along with U.S. extremes this year in rainfall, snowfall, flooding, and tornadoes, and many other stunning temperature and precipitation extremes elsewhere in the world in recent years as well as, as I posted on my TWC Facebook "fan" page, record-shattering 500 millibar heights in high latitudes. And all of this is happening while there's an alarming drop in the amount of Arctic sea ice."
The nature and context of the extremes is the difference between the 1930s and now.
The other item I found of interest is that as extreme weather events become more common, we are putting ever higher demands on energy consumption:
ReplyDeleteAs heat index soars, so does record-setting power demand, Vivian Kuo, CNN
http://www.cnn.com/2011/US/07/21/heat.wave.power.demand/
"...demand surged to its highest point ever in history Wednesday, peaking at 103,975 megawatts and surpassing the last record set on July 31, 2006. Previously in May, the agency said it expected peak demand for the summer to reach 93,842 megawatts, a projected 1.3% increase over 2010."