The Mongolian Plateau is one of the regions most sensitive to climate change, the more obvious increase of temperature in 21st century here has been considered as one of the important causes of drought and desertification. It is very important to understand the multi-year variation and occurrence characteristics of drought in the Mongolian Plateau to explore the ecological environment and the response mechanism of surface materials to climate change. This study examines the spatio-temporal variations in drought and its frequency of occurrence in the Mongolian Plateau based on the Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) (1982–1999) and the Moderate-resolution Imaging Spectroradiometer (MODIS) (2000–2018) datasets; the Temperature Vegetation Dryness Index (TVDI) was used as a drought evaluation index. The results indicate that drought was widespread across the Mongolian Plateau between 1982 and 2018, and aridification incremented in the 21st century. Between 1982 and 2018, an area of 164.38 × 10⁴ km²/yr suffered from drought, accounting for approximately 55.28% of the total study area. An area of approximately 150.06 × 10⁴ km² (51.43%) was subject to more than 160 droughts during 259 months of the growing seasons between 1982 and 2018. We observed variable frequencies of drought occurrence depending on land cover/land use types. Drought predominantly occurred in bare land and grassland, both of which accounting for approximately 79.47% of the total study area. These terrains were characterized by low vegetation and scarce precipitation, which led to frequent and extreme drought events. We also noted significant differences between the areal distribution of drought, drought frequency, and degree of drought depending on the seasons. In spring, droughts were widespread, occurred with a high frequency, and were severe; in autumn, they were localized, frequent, and severe; whereas, in summer, droughts were the most widespread and frequent, but less severe. The increase in temperature, decrease in precipitation, continuous depletion of snow cover, and intensification of human activities have resulted in a water deficit. More severe droughts and aridification have affected the distribution and functioning of terrestrial ecosystems, causing changes in the composition and distribution of plants, animals, microorganisms, conversion between carbon sinks and carbon sources, and biodiversity. We conclude that regional drought events have to be accurately monitored, whereas their occurrence mechanisms need further exploration, taking into account nature, climate, society and other influencing factors.

蒙古高原是对气候变化最敏感的地区之一，在21世纪，气温升高更为明显，被认为是干旱和荒漠化的重要原因之一。了解蒙古高原干旱的多年变化和发生特征，探索生态环境和地表物质对气候变化的响应机制，具有十分重要的意义。这项研究基于先进超高分辨率辐射计（AVHRR）归一化植被指数（NDVI）（1982–1999）和中等分辨率成像光谱仪（蒙古国），研究了蒙古高原干旱的时空变化及其发生频率。 MODIS）（2000–2018）数据集；温度植被干燥指数（TVDI）被用作干旱评估指数。结果表明，1982年至2018年期间，干旱在蒙古高原上很普遍，在21世纪干旱化加剧了。在1982年至2018年之间，面积为164.38×10⁴ km ² / yr遭受干旱，约占总研究面积的55.28％。面积约150.06×10 ⁴ km ²（51.43％）在1982年至2018年的259个生长季节中，遭受了160多次干旱。我们观察到干旱的发生频率取决于土地覆盖/土地利用类型。干旱主要发生在裸露的土地和草地上，两者均占研究总面积的约79.47％。这些地形的特点是植被少，降水稀少，从而导致频繁和极端的干旱事件。我们还注意到干旱的区域分布，干旱频率和干旱程度（取决于季节）之间存在显着差异。春季，干旱普遍存在，干旱频发，严重。在秋天，它们是局部的，频繁的和严重的；而在夏季，干旱是最普遍，最频繁的干旱，但程度较轻。温度的升高，降水的减少，积雪的持续消耗以及人类活动的加剧导致了水的短缺。更为严重的干旱和干旱化影响了陆地生态系统的分布和功能，导致植物，动物，微生物的组成和分布发生变化，碳汇和碳源之间的转化以及生物多样性。我们得出的结论是，必须准确地监测区域干旱事件，而其发生机制需要进一步探索，同时要考虑到自然，气候，社会和其他影响因素。更为严重的干旱和干旱化影响了陆地生态系统的分布和功能，导致植物，动物，微生物的组成和分布发生变化，碳汇和碳源之间的转化以及生物多样性。我们得出的结论是，必须准确地监测区域干旱事件，而其发生机制需要进一步探索，同时要考虑到自然，气候，社会和其他影响因素。更为严重的干旱和干旱化影响了陆地生态系统的分布和功能，导致植物，动物，微生物的组成和分布发生变化，碳汇和碳源之间的转化以及生物多样性。我们得出的结论是，必须准确地监测区域干旱事件，而其发生机制需要进一步探索，同时要考虑到自然，气候，社会和其他影响因素。