Simulation of climatic impacts of desertification in Northeast Brazil

ABSTRACT The climatic behavior of the Brazilian Northeast (BNE) was simulated considering a scenario where all its caatinga area was replaced by desert. Precipitation decreased in the region in almost every month of the year, mainly on the caatinga sector. Evapotranspiration showed decreases of great magnitude throughout the year, especially during the rainy season. Runoff presented overall increases, indicating a decrease of the water extracted by plant roots. Air temperature was the most affected variable, with increases of up to 6°C in some regions and an average increase of approximately 3°C in the caatinga area. In addition, there was a restorative mechanism associated with convergence of humidity that worked favoring precipitation although insufficient to prevent its reduction in the BNE.

摘要：本研究模拟了巴西东北部（Brazilian Northeast，BNE）的气候特征，设定其所有卡廷加植被（caatinga）区域均被荒漠替代的情景。结果显示，该区域年内几乎所有月份的降水量均出现下降，尤以卡廷加植被分布区域最为显著。全年蒸散发量均呈现大幅降低态势，雨季的降幅尤为突出。径流量整体呈上升趋势，表明植物根系提取的水量有所减少。气温是受影响最显著的变量，部分区域气温升幅可达6℃，卡廷加植被区域的平均气温升幅约为3℃。此外，存在一种与湿度辐合相关的修复机制，虽有助于促进降水，但仍不足以抵消巴西东北部的降水减少趋势。