Effects of regional vegetation cover degradation and climate change on dusty weather types

Dust sources of west and south west of Iran are mainly from interior lands and neighbouring countries such as Iraq, Syria, Saudi Arabia, and Kuwait which are influenced by climate fluctuations and land use/land cover (LULC) degradation. The aim of this research is to investigate the impacts of regional vegetation cover degradation (RVCD) and climate change on dusty weather types in Zagros Mountain in the west of Iran. The RVCD was evaluated using MODIS satellite image series from 2000 to 2016 and its trend was predicted by Markov chain test for 2030, 2060, and 2100. Daily data of nine climatic variables were used to identify the weather types (WTs) using principle component analysis and cluster analysis in the baseline period. The results showed that four principle components could account for 93 percent of data variances. The extreme temperatures, precipitation, and sunshine hours were predicted using HADCM3 and LARS-WG models under A1B scenario and wind speed and relative humidity computed using Man Kendall test to analyse the WTs from the past to the future. The findings indicated that six WTs could be observed of which about 77% and 84% of dusty days were recorded in Dusty WTs, including WT3 (warm/dry/windy) and WT4 (hot/very dry) during 1982–2000 and 2000–2016, respectively. Moreover, the frequency of Dusty WTs (WT3 and WT4) with the highest temperature and dryness in warm season will increase till 2060.