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The arid and semi-arid areas of Central Asia are especially susceptible and vulnerable to climatic change, thus making understanding the relationship between extreme climate and vegetation dynamics in recent decades very important. Based on the maximum value composite, trend analysis, Mann-Kendall test, correlation analysis, and cross-correlation analysis, this study investigated the variations of extreme climatic indices and their influences on vegetation dynamics using the Unified Gauged-Based Analysis data from the NOAA Climate Prediction Center (CPC) and the Global Inventory Monitoring and Modeling Studies (GIMMS) normalized difference vegetation index (NDVI) series of 1982–2015. In general terms, it is suggested that Central Asia has experienced more extreme precipitation and high temperature events, especially in the mountainous regions. The vegetation in Central Asia has significantly increased during the past 34 years at a rate of 0. 0006 ⋅ year - 1 . The NDVI is significantly and positively related to extreme precipitation and temperature intensity indices on a monthly scale, with strong spatiotemporal heterogeneity. The influences of extreme precipitation indices mainly occurred in May and June, without time lag on a monthly scale, while extreme temperatures exhibited significant relationship with maximum NDVI in April, with a time lag of at least 1 month. Analyzing the relationship between extreme climatic factors and vegetation dynamics on a monthly scale can help us to better understand the main limiting factors for vegetation growth in different growth periods compared with those on an annual scale. In the most severely affected regions, adaptation methods must be initiated, especially for improving the speed of disaster relief and reducing socioeconomic losses. The findings of this study will provide vital information for the ecological protection and sustainable development of Central Asia. Image 1 [ABSTRACT FROM AUTHOR]

• The contributions of drought to vegetation phenology are determined for different time scales. • Summer SM has a strong control on prolongation of LOS in plain areas of the Mongolian Plateau. • The sensitivities of vegetation phenology to droughts decreased with soil depths. • EOS was more sensitive to short-term drought as compared with SOS. Soil moisture (SM) plays a paramount role in maintaining plant growth. However, the understanding of the influences of SM dynamics on vegetation phenology is still insufficient. This is especially true for the arid and semi-arid regions, where moisture is the main limiting factor for vegetation growth. Therefore, by selecting the typical arid and semi-arid Mongolian Plateau as the study region, we evaluated the dynamics of SM and drought characterized by the standardized soil moisture index (SSMI) from 1982 to 2019 based on SM product derived from the fifth generation of the European Center for Medium-Range Weather Forecasts Interim Re-Analysis (ERA5). Their impacts on vegetation phenological indices, including the start of the growing season (SOS), the end of the growing season (EOS), and the length of the growing season (LOS), were further investigated. Our results showed that SM in the growing season had experienced a significant negative trend accompanying with the increment of SM droughts. A significantly abrupt change of SM occurred around 2000. The influences of SM on vegetation phenology displayed strong seasonal variations and weakened with soil depths. Except for some alpine areas in northwestern and southeastern parts and areas with artificial plantations, negative correlations between spring SM and SOS were generally found in the Mongolian Plateau, indicating that a decreasing SM was not conductive to an earlier SOS. Most plain areas showed a positive correlation between summer SM and EOS, while the relationship became stronger in autumn. Summer SM also had a strong control on prolonging the growing season. Furthermore, vegetation phenology was sensitive to drought, with a higher sensitivity in the EOS. Our findings have derived a better understanding on the effects of climate change, but also provided vital references to maintain sustainable development of ecosystems for the Mongolian Plateau and other arid and semi-arid regions worldwide. [ABSTRACT FROM AUTHOR]

• Studied JJJM region's ES balance, considering regional characteristics. • The adjusted model revealing higher ES balance in the east and north. • Temperature, precipitation, and grazing density primarily affect ES balance. • ES balance initially rises, then declines, facing rapid urbanization challenges. • Climate patterns and eco-engineering optimize ES balance, foster harmony. Ecosystem services (ES) are defined as the benefits of the natural environment that sustain human life. The analyses of the balance of ecosystem services (ES balance) and its driving factors are critical for achieving the region's sustainable development goals. This study explored the ES balance in the Beijing-Tianjin-Hebei-Inner Mongolia (JJJM) region, considering the region's rapid urbanization, implementation of ecological restoration projects, and intense agricultural and pastoral activities. It quantified the ES balance on different scales and selected nine natural and anthropogenic driving factors to reveal its spatio-temporal heterogeneity and change characteristics in 2000–2020. The main conclusions were as follows: (1) The ES balance in the JJJM region exhibited a significant spatial differentiation: generally higher in its eastern and northern areas and lower in its western and southern parts; (2) The ES balance in the Beijing-Tianjin-Hebei region showed a general trend of initial increase and subsequent decrease, while Inner Mongolia exhibited a continuous upward trend. High-value areas (>46) and low-value areas (<10) increased significantly. 27.33% of the areas showed a continuous improvement trend, but the overall ES balance was declining at a rate of 0.110–0.166/year; (3) Among natural factors, temperature had the highest explanatory power (0.409) regarding ES balance, while among anthropogenic factors, grazing density had the highest explanatory power (0.311). The interaction between temperature and precipitation is the strongest; (4) During the study period, the explanatory power of anthropogenic factors increased over time, indicating that human activities were exerting a gradually increasing impact on the JJJM region's ES balance. Overall, this study enhanced spatio-temporal understanding of the driving factors of ES balance differentiation, and offered a scientific basis for ecological policy-making and the development and transition of socio-economic activities, which could prove to be invaluable in promoting the coordinated development of regional ecologies and economies. [ABSTRACT FROM AUTHOR]

• An evolution pattern of wind speed system was constructed, applicable worldwide. • Conjugate prior and composite distribution are valid for extending distribution. • Downscaling functions are distributions of shape parameter and emergences of system. • Static PDFs describe deterministic characteristics of stochastic wind speeds. • Dynamic relationship among PDFs reflect evolution of system, embodying constructivism. Statistical characteristics of meteorological elements play an important role in climate assessment. The statistical study of wind speeds in near-surface flow fields is mainly concerned by wind energy. Determinacy and stochasticity of wind speeds are important for wind power generation system. Probability density function (PDF) is the main approach to describe wind speed distribution. Here we show a theoretical evolution pattern of statistical characteristics of stochastic wind speed system was constructed. This is simple and applicable worldwide. Poisson, gamma (or Weibull), and negative binomial distribution corresponds to the timescale of 10 min, less than one year, and many years, respectively. Downscaling functions eliminating a parameter are the distributions of the shape parameter, and statistically are the emergence of each level of system. Variations of the scale parameter characterizing thermal convection are reflected in wind speed distributions through variations of the shape parameter representing forced convection. The emergence of Poisson, gamma, and negative binomial distribution is the result of spatial interaction, spatial interaction that varies with time, and space, time and inheritable instructions, separately. Stochasticity of wind speed system is intrinsic. Static PDFs describe the deterministic statistical characteristics of stochastic wind speeds, which emphasizes that determinacy contains stochasticity. Dynamic relationships among levels of system reflect the evolution of system, which embodies constructivism. From the view of the discontinuous statistical characteristics, stochastic wind speed system is catastrophic. These results provide a new path for cross-level research of complexity science. [ABSTRACT FROM AUTHOR]