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Investigating oasis effects of different oasis-town configurations is key to understanding the ecological stability of the oasis. However, previous studies have not considered the impacts of oasis–town configurations on oasis effects. In this study, the Weather Research and Forecasting (WRF) model was used to conduct a series of 1-km-resolution simulations of the Hami Oasis, Xinjiang of China, to examine how different oasis–town configurations influenced the oasis effects. The actual landscape and four hypothetical landscapes were considered. Results indicated that the WRF model effectively reproduced the trends of the surface temperature, 2-m air temperature, 2-m relative humidity, and 10-m wind speed. It was also found that the effects of the town on the oasis were substantially greater when the former was located at the center of the oasis, rather than on the margin. At 850 hPa, the center of the temperature field was downstream from that of the wind field, whereas both coincided at lower levels. When the size of the town was doubled, the convergence center over the town weakened the strength of the divergent low-level winds from the oasis. This facilitated the infiltration of dry air from the surrounding desert into the oasis, which is detrimental to the healthy development of the oasis. Placing a town at the margin of the oasis is therefore advantageous to the development of the cold island, whereas a town at the center of the oasis is beneficial to the comfort of the residents.

Precipitation is critical for maintaining the stability of an ecosystem, especially in arid regions. This study primarily focuses on climatic changes during present (from 1985 to 2005) and future (from 2040 to 2059) periods in Xinjiang, Northwest China. In this study, the Weather Research and Forecasting model is implemented in Xinjiang to efficiently predict the future climate. Moreover, the National Climate Research Center Community Climate System Model version 4 is employed for the mid-21st century under representative concentration pathways 4.5 and 8.5 (RCP4.5 and RCP8.5, respectively). Our results indicate that the amount of annual precipitation will increase in the future under RCP4.5 and RCP8.5 in Xinjiang, especially in mountainous areas. The increase in precipitation is predicted to be much smaller under RCP8.5 than under RCP4.5, except in Southern Xinjiang. Moreover, the increasing precipitation predicted in Xinjiang implies that the current humid and warm conditions will persist, thereby further indicating that Xinjiang is still currently suffering from a dry climate. The largest increase in seasonal precipitation is predicted to occur in spring and summer in Tianshan and Northern Xinjiang, whereas this phenomenon is predicted to occur in spring and winter in Southern Xinjiang. In addition, it is predicted that daily heavy precipitation events will occur more frequently in various subregions of Xinjiang, although light rain events will remain dominant. Finally, the relative humidity is closely related to the changes in annual and seasonal precipitation.

In addition to land cover change (LCC), land use intensity change (LUIC) is another dominant pathway through which anthropogenic activities influence regional climate. Although the climatic effects of LCC have been investigated extensively, little is currently known about the effects of LUIC. In this study, we assess land use and cover change in China over the last three decades in terms of LCC and LUIC and investigate their climatic effects using the observation minus reanalysis method. Results indicate that nearly half of the stations have experienced LUIC, and the climatic response of these stations exhibit different or even opposite signals compared to those that have experienced LCC. With regard to LCC, it is found that urbanized stations generally exert a warming effect on local temperatures, whereas cropland expansion is likely to introduce a cooling effect. In the case of LUIC, the present study demonstrates that the intensification of grassland tends to lead to warming because of the decreased albedo. However, a cooling effect from the enhanced evapotranspiration (ET) dominates local temperature variations in intensified cropland stations. The absence of correlations between albedo/ET and land management changes in urban stations illustrates the inherent complexity of local climate change. The findings of the present study provide a deeper understanding of land–atmospheric interactions and could guide future land-use planning and management to achieve potential climatic benefits.