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I’ll be blogging for the next couple days from the 2010 Experimental Biology conference. Today’s session that caught my eye was on measuring the effects of climate change on organisms in their own niches. It turns out that some microenvironments act like lenses, focusing small changes in climate into much larger effects on resident organisms. I also attended a good session on science communication and policy, which will receive a longer and more thoughtful post to come later.

When people hear that the global temperature has increased about 1 degree C in recent years as a result of global warming, it’s understandable that they aren’t really impressed. “One degree? It changes more than that day to day!” Speakers during this session showed how in certain ecological niches, the real difference in terms of physiological effects on an organism are quite larger.
Brian Helmuth from the University of South Carolina kicked off the session with a discussion of tools and models for downscaling the global phenomena to microenvironments. He showed that there’s little correlation between the internal temperature of an animal and the air or water temperature surrounding it. Furthermore, the air or water temperature changes don’t result in the same relative change in temperature for all the organisms in the microenvironment. In other words, a 1 degree rise in air temp tells you pretty much nothing about what effect that has on an organism. Using air temps as a proxy for environmental stress is like trying to guess how what the weather is like outside based on what color shoes people are wearing.

To address this, he developed a sophisticated model for predicting the differential effect of climate change on different organisms, basically an internal “weather forecast” for an organism. They measure a few coefficients such as radiant heat transfer (based on how much insulation the organism has) and evaporative heat loss (from sweating, for example). What this then allows them to do is to properly predict the actual temperature shift as it’s experienced by the individual organism.
It doesn’t take too much imagination to realize that this approach could be extended to look at ocean acidification and other environmental stressors as well. With these new tools, scientists can now predict the effect that microenvironmental changes will have on habitats and start to look at how this interacts with pollution exposure and other challenges facing an organism.

_{Data guys, he mentioned a huge amount of time series temperature data on organisms, stretching back 10 years at a 10 minute resolution. Impressive?}