Drylands are home to more than 38% of the world's population and are one of the most sensitive areas to climate change and human activities. This review describes recent progress in dryland climate change research. Recent findings indicate that the long‐term trend of the aridity index (AI) is mainly attributable to increased greenhouse gas emissions, while anthropogenic aerosols exert small effects but alter its attributions. Atmosphere‐land interactions determine the intensity of regional response. The largest warming during the last 100 years was observed over drylands and accounted for more than half of the continental warming. The global pattern and interdecadal variability of aridity changes are modulated by oceanic oscillations. The different phases of those oceanic oscillations induce significant changes in land‐sea and north‐south thermal contrasts, which affect the intensity of the westerlies and planetary waves and the blocking frequency, thereby altering global changes in temperature and precipitation. During 1948–2008, the drylands in the Americas became wetter due to enhanced westerlies, whereas the drylands in the Eastern Hemisphere became drier because of the weakened East Asian summer monsoon. Drylands as defined by the AI have expanded over the last 60 years and are projected to expand in the 21st century. The largest expansion of drylands has occurred in semiarid regions since the early 1960s. Dryland expansion will lead to reduced carbon sequestration and enhanced regional warming. The increasing aridity, enhanced warming, and rapidly growing population will exacerbate the risk of land degradation and desertification in the near future in developing countries.

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A decadal change in the frequency of dust outbreaks for April over East Asia using World Meteorological Organization (WMO) synoptic data was identified. The causes of the decadal change can be defined in terms of aeolian erosivity (i.e., ability of wind to cause erosion represented by wind speed) and erodibility (i.e., susceptibility of soil and land surface to wind erosion represented by the threshold wind speed for dust outbreak). Dust outbreak frequency (fDO) increased at many stations in Mongolia, Inner Mongolia, northeastern China, and the Hexi Corridor from the 1990s to the 2000s. Especially, remarkable increases were observed for Mongolia. Strong wind frequency (fu>ut5%) decreased or changed little over the period of study, and the 5th percentile of the threshold wind speed for dust outbreak (ut5%) decreased at many stations in Mongolia, eastern Inner Mongolia, and northeastern China. This suggests changes in erodibility factors increased fDO in these regions. There are stations where fu>ut5% increased and ut5% remained relatively constant in western Inner Mongolia and the Hexi Corridor. This suggests changes in the erosivity factor increased fDO at these locations. The change in erodibility is linked, in part, to the effect of dead leaves of grasses in spring, which are the residue of vegetation in summer from the previous year, which can cause an increase in the threshold wind speed.

Habitat loss and habitat fragmentation caused by anthropogenic activities are the main factors that constrain long-distance movement of ungulates. Mongolian gazelles (Procapra gutturosa) and Asiatic wild asses (Equus hemionus) in Mongolia are facing habitat fragmentation and loss. To better understand how their movements respond to potential anthropogenic and natural barriers, we tracked 24 Mongolian gazelles and 12 wild asses near the Ulaanbaatar–Beijing Railroad and the fenced international border between Mongolia and China between 2002 and 2012. None of the tracked gazelles crossed the railroad, even though gazelles were captured on both sides of the tracks at the start of the study. Similarly, we did not observe cross-border movements between Mongolia and China for either species, even though some animals used areas adjacent to the border. The both species used close areas to the anthropogenic barriers more frequently during winter than summer. These results suggest strong impacts by the artificial barriers. The construction of new railroads and roads to permit mining and other resource development therefore creates the threat of further habitat fragmentation, because the planned routes will divide the remaining non-fragmented habitats of the ungulates into smaller pieces. To conserve long-distance movement of the ungulates in this area, it will be necessary to remove or mitigate the barrier effects of the existing and planned roads and railroads and to adopt a landscape-level approach to allow access by ungulates to wide ranges throughout their distribution.