Open AccessSimulated Links between Deforestation and Extreme Cold Events in South America
Author(s) -
D. Medvigy,
R. L. Walko,
Roni Avissar
Publication year - 2012
Publication title -
journal of climate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.315
H-Index - 287
eISSN - 1520-0442
pISSN - 0894-8755
DOI - 10.1175/jcli-d-11-00259.1
Subject(s) - amazon rainforest , deforestation (computer science) , climatology , environmental science , climate change , subtropics , ecosystem , gcm transcription factors , tropics , population , atmospheric sciences , geography , general circulation model , ecology , geology , oceanography , demography , sociology , computer science , biology , programming language
Many modeling studies have indicated that deforestation will increase the average annual temperature in the Amazon. However, few studies have investigated the potential for deforestation to change the frequency and intensity of extreme events. This problem is addressed here using a variable-resolution GCM. The characteristic length scale (CLS) of the model’s grid mesh over South America is 25 km, comparable to that used by limited-area models. For computational efficiency, the CLS increases to 200 km over the rest of the world. It is found that deforestation induces large changes in the frequency of wintertime extreme cold events. Large increases in cold event frequency and intensity occur in the western Amazon and, surprisingly, in parts of southern South America, far from the actual deforested area. One possible mechanism for these remote effects involves changes in the position of the subtropical jet, caused by temperature changes in the Amazon. Increased understanding of these potential changes in extreme events will be important for local agriculture, natural ecosystems, and the human population.