Southern Annular Mode drives multicentury wildfire activity in southern South America

• Published in: Proceedings of the National Academy of Sciences
• Main Authors: Holz, Andrés, Paritsis, Juan, Mundo, Ignacio A., Veblen, Thomas T., Kitzberger, Thomas, Williamson, Grant J., Aráoz, Ezequiel, Bustos-Schindler, Carlos, González, Mauro E., Grau, H. Ricardo, Quezada, Juan M.
• Format: Text
• Language: English
• Published: National Academy of Sciences 2017
• Subjects: Physical Sciences; Antarctic; Antarc*
• Online Access: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5594661/; http://www.ncbi.nlm.nih.gov/pubmed/28827329; https://doi.org/10.1073/pnas.1705168114

Fire is a key ecological process affecting ecosystem dynamics and services, driven primarily by variations in fuel amount and condition, ignition patterns, and climate. In the Southern Hemisphere, current warming conditions are linked to the upward trend in the Southern Annular Mode (SAM) due to ozone depletion. Here we use tree ring fire scar data obtained from diverse biomes ranging from subtropical dry woodlands to sub-Antarctic rainforests to assess the effect of the SAM on regional fire activity over the past several centuries. Our findings reveal a tight coupling between fire activity and the SAM at all temporal scales and in all biomes, with increased wildfire synchrony and activity during the 20th century compared with previous centuries.