Authors: Seyed Kazem Alavipanah, Sirous Haashemi, Ali Kazemzadeh-zow, Ali Darvishi Bloorani, Saba Asadolah
Abstract:Land surface temperature (LST) one of the most important parameter in urban climate and urban energy balance. Impervious surfaces (IS) and vegetation abundance are the most important biophysical surface properties determinant urban LST. LST has directly effect on Surface Urban Heat Island (SUHI) that affects and control both UHI in Urban Canopy Layer (UCL) and Urban Boundary Layer (UBL). LST has been studied using remote sensing data increasingly. LST by creating water tension in urban ecosystems play an important role in the amount of water and energy consumption, especially in summer times. The aim of this study is to evaluate the effects of LST on water consumption during warm months in four regions of water organization of Tehran. Time series of Landsat 8 TIRS data were used as daily LST and the product of MODIS (MOD011) were used as night LST. Daily LST were retrieved by Split Window algorithm (SW). Tehran water organization data were used for evaluating the per capita water consumption (PCWC) variation. The results show that different regions with different surface properties such as IS, Fractional Vegetation Cover (FVC) and elevation led to different LSTs. The results also show the increase of PCWC from April to August and decrease in September. These time fluctuations are coincides with variations of LST. In order to compare PCWC value in different regions, the monthly Rate of PCWC (RPCWC) were computed by normalizing monthly PCWC based on April. Regions with high monthly LST are coincide high monthly RPCWC. The relationship between monthly RPCWC and monthly average of LST shows positive correlation (R2= 0.63 and Pearson correlation= 0.76). This study shows that LST caused PCWC and RPCWC increase in warm months. The results offer a reliable information to regulate water use policy in Tehran. Considering the fact that most of people in warm region are poor, so the policy of costing water should consider the importance of environmental factors such as LST.
Keywords: land surface temperature, per capita water consumption, rate of per capita water consumption