Premium
Vegetation dynamics contributes to the multi‐decadal variability of precipitation in the Amazon region
Author(s) -
Wang Guiling,
Sun Shanshan,
Mei Rui
Publication year - 2011
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2011gl049017
Subject(s) - amazon rainforest , precipitation , climatology , vegetation (pathology) , environmental science , geology , atmospheric sciences , physical geography , meteorology , geography , ecology , medicine , pathology , biology
Precipitation in most of the Amazon shows multi‐decadal fluctuations that were linked to oceanic forcing in the Atlantic. This modeling study shows that vegetation dynamics may play a major role in such low‐frequency variability in the Amazon. Despite the large amount of annual precipitation, the presence of a dry season (albeit short) facilitates a strong impact of dynamic vegetation on precipitation persistence in the model. The year‐to‐year variation of net primary productivity (NPP) is dominated by that of the dry season NPP. As a result, above‐normal (below‐normal) precipitation in a particular year can enhance (suppress) vegetation growth, leading to widespread increase (decrease) of vegetation density in the subsequent year. Precipitation in the subsequent year is therefore more likely to be above (below) normal. This damping effect of vegetation enhances low‐frequency variability of precipitation and leads to recurrent droughts or floods, a result previously considered characteristic of arid and semi‐arid regions.