When you walk through a forest, you are surrounded by carbon. Every branch and every leaf, every inch of trunk and every tendril of unseen root contains carbon pulled from the atmosphere through photosynthesis. And as long as it stays stored away inside that forest, it’s not contributing to the rising concentrations of carbon dioxide that cause climate change. So it’s only natural that we might want to use forests’ carbon-storage superpower as a potential climate solution in addition to reducing human greenhouse gas emissions.

But climate change itself might compromise how permanently forests are able to store carbon and keep it out of the air, according to a new paper by researchers at University of Utah and UC Santa Barbara. The study considered how different regions and tree species will respond to climate change. The authors found a wide range of estimates for the amount of carbon that forests in different regions might gain or lose as the climate warms. Importantly, the researchers found that regions most at risk of losing forest carbon through fire, climate stress or insect damage are precisely those regions where many forest carbon offset projects have been set up.

“Forest health and carbon-storage potential is evolving rapidly due to climate change,” said co-author Anna Trugman, an assistant professor at UC Santa Barbara. “The balance of increasing productivity from higher CO2 levels and accelerating losses from disturbances will determine the fate of forests as a carbon sink.”

But the models also revealed significant risks of losing carbon from forests through the triple threat of fire, climate stress and insect damage. Without these stresses, forests might be able to pack away 9.4 petagrams of carbon nationwide by the end of the 21st century. A petagram is equal to a quadrillion grams — about 25 times the mass of all humans on Earth. However, with these risks, the models projected a net gain in forests of between 3 and 5 petagrams.

Original source can be found here.