The oasis effect and summer temperature rise in arid regions - case study in Tarim Basin

This study revealed the influence of the oasis effect on summer temperatures based on MODIS Land Surface Temperature (LST) and meteorological data. The results showed that the oasis effect occurs primarily in the summer. For a single oasis, the maximum oasis cold island intensity based on LST (OCI(LST)) was 3.82 °C and the minimum value was 2.32 °C. In terms of the annual change in OCI(LST), the mean value of all oases ranged from 2.47 °C to 3.56 °C from 2001 to 2013. Net radiation (R(n)) can be used as a key predictor of OCI(LST) and OCI(temperature) (OCI based on air temperature). On this basis, we reconstructed a long time series (1961–2014) of OCI(temperature) and T(base)(air temperature without the disturbance of oasis effect). Our results indicated that the reason for the increase in the observed temperatures was the significant decrease in the OCI(temperature) over the past 50 years. In arid regions, the data recorded in weather stations not only underestimated the mean temperature of the entire study area but also overestimated the increasing trend of the temperature. These discrepancies are due to the limitations in the spatial distribution of weather stations and the disturbance caused by the oasis effect.