New research from a multi-university team of biologists shows what could be a startling drop in the amount of carbon stored in the Sierra Nevada mountains due to projected climate change and wildfi re events. The study, “Potential decline in carbon carrying capacity under projected climate-wildfi re interactions in the Sierra Nevada,” published this week in Scientific Reports, shows another facet of the impact current human-made carbon emissions will have on our world if big changes aren’t made.
“What we’ve been trying to do is really understand how changing climate, increases in temperatures and decreases in precipitation, will alter carbon uptake in forests,” said University of New Mexico Assistant Professor Matthew Hurteau, a coauthor on the paper. “Th e other aspect of this work is looking at disturbance events like large scale wildfi res. Th ose events volatilize a lot of carbon and can kill many trees, leaving fewer trees to continue to take up the carbon.” “Our simulations in the Sierra Nevada show that the mean amount of carbon loss from the forests under these projections could be as large as 663 teragrams,” said Hurteau. “Th at’s equal to about 73 percent of the total above ground carbon stock estimated in California vegetation in 2010.”
Hurteau and his colleagues used climate projections from the Intergovernmental Panel on Climate Change and run ecosystem model simulations, where they look at individual tree species in the Sierra Nevada to understand how projected climate and wildfi re will infl uence where those trees will be found in the future and how quickly they’ll grow.
Using that data, researchers are then able to determine the expected carbon uptake — which, if things continue moving in the same direction, will see huge declines across the Sierra Nevada mountain range over the next 250 years. The two factors that influence these fi ndings are changes in climate and the likelihood of large scale forest fires. Because California is experiencing warmer and dryer conditions due to global warming, certain tree species are not able to fl ourish across particular geographic regions like they once were. Less tree growth, means less carbon uptake in forests. Th e study also shows that wildfi res will play a big role in the reduction of stored carbon. And while many of these incidents will occur naturally, Hurteau says we are, in part, to blame for their signifi cance. Source: University of New Mexico
