A team at the University of Arizona has a neat piece of work in PNAS this week isolating the temperature variable in the tree mortality we’re seeing in the West. The scientists put piñon trees from northern New Mexico (I’m so parochial) into Biosphere 2 down by Phoenix, using the facility’s ability to control temperature to understand the role of temperature in drought-induced piñon dieoff. Their results should not be surprising. The warmer it is, the more likely for a given moisture deficit that the trees will die. Given the forecasts for the coming century, I don’t have to connect the dots for you.
This builds on a couple of key papers over the last few years, including one by Breshears et al. in PNAS and the van Mantgem et al. paper from earlier this year in Science.
More at the work blog, and I’ll have a story in the morning paper.
i haven’t read the paper, but I wonder if there is a single scientist alive who would expect that the response of a tree to a substantial and instantaneous change in the climate will be the same as the response to a century of annually-imperceptible change?
James –
I can’t speak for the scientists involved, but I know from my conversations with them that their controlled B2 experiment came in response to the relatively uncontrolled experiment on the landscape, in which they saw excess tree mortality in response to a half century of annually-imperceptible change. See Breshears et al., PNAS October 18, 2005 vol. 102 no. 42 15144-15148
James, bear in mind that we’re looking at increasingly frequent and more severe droughts rather than something that could be described as smooth.