Temporal dynamics of albedo and climate in the sparse forests of Zagros

Abstract

Land surface albedo is an important parameter affecting the climate locally and globally. A synthesis of current studies urgently calls for a better understanding of the impact of climate change on the surface albedo. The Middle East is expected to experience major climatic changes during the coming decades and has already undergone major losses in its vegetation cover. This study explores how climate change related disturbances, such as severe drought and fire events, influence albedo trends in the largest remaining forest area of the Middle East, the Zagros Mountains. We analyzed time series of albedo, Leaf Area Index (LAI), burn severity (dNBR), and the number of fire events all obtained from MODIS satellite images between 2000 and 2016, together with climatic data from 1950 to 2016. The Zagros area is continuously suffering from low precipitation, high temperatures, and evermore-frequent wildfire events. Our large-scale analysis revealed that albedo is linked to precipitation, number of fire events, dNBR,and LAI with the average correlation coefficients of -0.26, -0.50, 0.17, and -0.72, respectively. Using four study sites located in different parts of the Zagros area, we showed disturbances influence albedo differently. Drought condition resulted in a marginal increasing trend in albedo, whereas fire events resulted in a decreasing trend. This article is the first report linking climate change with albedo in Iran. (C) 2019 The Authors. Published by Elsevier B.V.