Based on the data of daily precipitation and mean temperature from 80 national meteorological stations in Anhui Province from 1961 to 2022, the processes of regional extreme climate events are identified according to the objective identification technique for regional extreme events. Average intensity, duration and average influence range are further extracted, which are applied to establish comprehensive intensity assessment model, and then regional high temperature and drought processes in 2022 are comprehensively evaluated. The results show that the average temperature in Anhui Province in the summer of 2022 is 2.2 ℃ higher than normal, which is the highest in the same period since 1961.The precipitation in 2022 is 40% less than normal, which is the fourth lowest since 1961. Persistent high temperature and little rainfall led to continuous severe drought in summer and fall in the south of the Huaihe River in Anhui Province. There are six regional high temperature processes in the summer of 2022, and the high temperature process from August 1 to 23, 2022 has reached the "super strong" level, which rank the fourth in history and is inferior to the high temperature processes in 1966, 1967 and 2013. However, the annual cumulative comprehensive intensity of high temperature in 2022 reached 4496, which is the highest since 1961.Two regional drought processes occurred in the summer and autumn of 2022. Compared with the nine strongest regional drought processes in summer and autumn since 1961, by the end of September 30, 2022 the regional drought process since July 28 has lasted 65 days, and the intensity level is "super strong", which is inferior to the processes in 1966, 1967, 1978 and 2019.

Based on hourly temperature and precipitation grid data of CMA land data assimilation system (CLDAS), ground meteorological observation data at 119 weather stations of Inner Mongolia and the spatial distribution of irrigated crop fields, the key meteorological factors and climatic division indexes were determined by considering fully planting technology and agricultural climatic characteristics of sunflower following spring wheat harvest in agro-climatic ecological regions of Inner Mongolia. And taking suitable growth days and climate suitability in the whole growth period as zoning indicators, the refined climatic suitability division of sunflower following spring wheat harvest in Inner Mongolia was studied under the operation of ArcGIS. The results show that the heat shortage and drought in growing season mainly restricted the regular growth and yield formation of sunflower following spring wheat harvest in Inner Mongolia, and the whole region was divided into unsuitable zone, more suitable zone, suitable zone and the most suitable zone. The irrigation conditions in Hetao irrigation district, Tumochuan plain and West Liaohe plain were better, which were particularly suitable to the growth of sunflower following spring wheat harvest, so these regions were the most suitable districts of sunflower growing. Due to serious shortage of heat resource in most areas of middle and eastern Inner Mongolia and the deficit of precipitation in the north of mid-western Inner Mongolia after the transplanting, the sunflower following spring wheat harvest was quite immature, so these regions were unsuitable areas of sunflower growing. The climatic suitability division of sunflower following spring wheat harvest based on grid data of CLDAS was consistent with the division distribution based on meteorological data of weather stations in Inner Mongolia, but the details of CLDAS data division were more refined than that of stations data. Hetao irrigation district was the most suitable area of sunflower following spring wheat harvest in Inner Mongolia, which was accord with the current layout of sunflower following spring wheat harvest. Therefore, this division result could provide some references for the rational layout of sunflower following spring wheat harvest in Inner Mongolia under the background of climate change.

Based on soil moisture and meteorological elements data at four pasture observation stations in typical steppe of Inner Mongolia from 1981 to 2015, the correlations between multi-time-scales meteorological drought indexes and soil relative moisture at different depths in spring, summer and autumn were comparatively analyzed, and the applicability of these drought indexes to drought monitoring was explored in typical steppe of Inner Mongolia. And on this basis, the prediction models of soil relative moisture at different depths were built by using multiple linear regression method in different seasons. The results show that the soil relative moisture at 0-20 cm depth in three seasons was affected by atmospheric water balance in the past two months, while the timescales influencing soil relative moisture at 0-50 cm and 0-100 cm depths were different in typical steppe of Inner Mongolia. In spring, the soil relative moistures at 0-50 cm and 0-100 cm depths were significantly regulated by previous annual precipitation. In summer, the soil relative moisture at 0-50 cm depth was closely related to atmospheric moisture balance in the past two months, while the soil drought at 0-100 cm depth was mainly controlled by precipitation deficit in the past 2-6 months. In autumn, the soil relative moisture at 0-50 cm depth was significantly influenced by previous precipitation for 3-6 months, while that at 0-100 cm depth was closely correlated with the balance between precipitation and evapotranspiration in the past three months, and the influence of meteorological droughts in the past six months and above was obvious. CI, MCI and PDSI had higher correlation with soil relative moisture at different depths than other meteorological drought indices in different seasons due to taking into account the comprehensive effects of long-term and short-term atmospheric water deficit. The established prediction models of soil relative moisture based on previous meteorological drought indexes could better capture the change of soil moisture in typical steppe, and they could support the drought monitoring and predication of pasture to some extent.

Based on daily climatic elements data simulated by five global circulation models (GCMs) in the coupled model intercomparison project phase 5 (CMIP5) under three representative concentration pathways (RCPs), daily mean temperature, precipitation and solar total radiation from 50 weather stations, and growth period and per unit yield of single-season rice in the south of the Huaihe River of Anhui Province, the climate changes during the growth period of single-season rice in the south of the Huaihe River of Anhui Province were estimated in the 21st century. And on this basis, the climatic productivity potential (YCPP) of single-season rice and its response to climate changes during the growth period were estimated in near term (2018-2039), middle term (2040-2069), and long term (2070-2099) by using the productivity decay method. The results are as follows: (1) The simulation ability of five GCMs to temperature and precipitation in the south of the Huaihe River of Anhui Province was well, and the simulation effect of temperature was better than that of precipitation. (2) The different growth stages of single-season rice in the south of the Huaihe River would be ahead under different RCPs scenarios in the 21st century, and the whole growth period would shorten. The temperature during whole growth stage of single-season rice would continue to increase under different climate scenarios in the future, and the warming rate in the north would be higher than that in the south, especially under RCP8.5 scenario. The precipitation would present a fluctuating change as a whole, but it would increase obviously in southern region, while the solar total radiation would decrease significantly in the future. (3) The estimated climatic productivity potential of single-season rice under different RCPs scenarios would decrease significantly in the 21st century compared with the baseline period, especially in long period. (4) The climatic productivity potential of single-season rice would be negative and positive correlated significantly with mean temperature and precipitation during whole growth stage from 2018 to 2099, respectively, and the negative effect of climate warming on climatic productivity potential would be prominent. In conclusion, the climate change in the future would not be conducive to the improvement of climatic potential productivity of single-season rice in the south of the Huaihe River of Anhui Province.

Based on daily meteorological observation data from 119 weather stations from the heading to the maturity stages (from June to August) of spring wheat, agro-meteorological observation data from 11 agro-meteorology stations and wheat varieties tests from 1981 to 2010, sown area and yield of spring wheat from 1987 to 2015 in Inner Mongolia, and combined geographic information data and the second national land survey data, the refined risk of dry-hot wind disaster for spring wheat in Inner Mongolia was evaluated according to natural disasters systematic analysis theory, and some suggestions that was suitable for planting of spring wheat were put forward. The results show that the dry-hot wind risk of spring wheat in western region of Inner Mongolia including Alxa League, northern Bayannur city and northwestern Ordos city was the highest, while that in mountainous area of Great Khingan, Yanshan hilly area, southern slope of Yinshan mountain was the lowest. The dry-hot wind risks in other regions were in moderate level to moderate-low level. The precision of dry-hot wind risk division of spring wheat in Inner Mongolia was higher, which was well consistent with the change of thousand-seed weight and yield of spring wheat. The division result can reflect actual situation in Inner Mongolia as a whole and provide important references for preventing dry-hot wind disaster of spring wheat.