Publications

Jahangir, MH; Arast, M (2020). Remote sensing products for predicting actual evapotranspiration and water stress footprints under different land cover. JOURNAL OF CLEANER PRODUCTION, 266, 121818.

Abstract
The changes of evapotranspiration (ET) in temporal periods should be evaluated and monitored, because of its importance in the management of water stresses. For this purpose, the actual ET rate and water shortage of Qom basin-Iran were estimated using Surface Energy Balance System-Iran (SEBS-Iran) with MODIS images of two wet and dry years (2000 and 2014 respectively) selected from 1986 to 2018. The results were compared with the measured stations data and MOD16 model. The NASA MODIS MOD16A2 operational product provides 500-m 8-day global ET estimates extending. The correlation results showed a good relationship between estimated and measured ET, however, SEBS in the wet year showed better performance compared to the MOD16 (R-2 = 0.93). In both wet and dry years, the maximum mean water stress was observed in both SEBS-Iran and MOD16 in arid and agricultural lands, respectively. The SEBS-Iran showed significant differences that the maximum and minimum water stress were observed in 2014 in barren land (0.78) and urban areas (0.44), respectively. In barrer lands, the water stress of MOD16 is lower than real value, which shows the weak performance of MOD16 in the arid area compared to the SEBS-Iran. An increase in normalized difference vegetation index (NDVI) and land surface temperature (LST) values led to increasing water stress. There is a correlation of water stress with the indices in both years (R = 0.74). In 2000, 2014, NDVI ranges were 0.31-0.68 and 0.15-0.53, respectively. In a dry year, by decreasing normalized difference moisture index (NDMI), water stress rate was increased. The result showed that in determining ET and water stress in dry and semi-dry areas, SEBS-Iran model demonstrates good performance in presenting more accurate and close to real results. Hence, SEBS-Iran model can be used in the field of water policymaking and management.

DOI:
10.1016/j.jclepro.2020.121818

ISSN:
0959-6526