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The changes of annual average, minimum and maximum temperature (Tavg, Tmin and Tmax) in China over 1961–2020 were examined based on the Chinese gridded observation dataset (CN05.1), and the relative contributions of Tmin and Tmax to the tendency of Tavg were addressed. The results show that the nationwide mean warming rate reached 0.29°C·decade−1 for Tavg, 0.39°C·decade−1 for Tmin and 0.24°C·decade−1 for Tmax, respectively, from 1961 to 2020, which depended on temporal windows. The relative contributions of Tmin and Tmax to the trends of Tavg over China during 1961–2020 are 56% and 44%, respectively. On the spatial scale, the majority of China exhibits a greater relative contribution of Tmin than Tmax, except for some areas along the Hu Huanyong Line. As in the case of the warming rate, the temporal patterns of the magnitude of the relative contribution of Tmin and Tmax are also identified. For the first 30 years (1961–1990), Tmin is the primary contributor to changes in the trend of Tavg over a broad area excluding the Qinling Mountain‐Huai River to the Nanling Mountain. The national average magnitudes of the relative contribution of Tmax is slightly larger than Tmin in the latter 30 years (1991–2020). The areas with larger contributions of Tmax are mainly scattered along Hu Huanyong Line, the southern part of the Qinghai‐Tibet Plateau and the patchy parts of Northwest China. Changes in downward longwave radiation, solar radiation, cloud cover, land use, soil moisture, atmospheric circulation and urbanization likely accounted for much of the trend difference of Tmin and Tmax, thereby leading to various relative contributions across different regions during different periods. The warming mechanisms in China have been subjected to novel changes. The study could provide information for decision making on scientific response to warming. [ABSTRACT FROM AUTHOR]

The impact of global warming on extreme precipitation over China is projected based on CMIP5 simulations under three representative concentration pathway scenarios. When global warming is 1.5 °C above pre‐industrial (1861–1890), precipitation intensity and frequency increase, which leads to an increase relative to the period 1986–2005 in total wet daytime precipitation in northeast China, north China, and the Qinghai–Tibet Plateau. However, south China and southwest China experience fewer precipitation days and less total precipitation despite increasing simple daily intensity (SDII). Under 2 °C of warming, the number of wet days (R1mm) increases north of 30°N and decreases to the south, whereas consecutive dry days (CDD) displays the opposite pattern. The other eight extreme precipitation events increase during the simulation period nationwide, with varying intensity. An increase in global warming from 1.5 to 2 °C is projected to lead to an increase in precipitation intensity over China, except for some scattered regions in the northwest and southwest of the country. More frequent extreme precipitation days are also expected, although decreases in R1mm are projected in north China and extend to northwest China. An overall small decrease in CDD is predicted for China. All annual regional‐mean precipitation events have an apparent linear relationship with global mean temperature, except for CDD. The rate of increase of extreme precipitation with temperature in the future on an annual scale is much faster than for a reference period (1986–2005), whereas no noticeable difference exists on a daily scale. The relationships between daily precipitation extremes and temperature for the present day and for the future show a quadratic polynomial structure, increasing up to 19 °C but decreasing at higher temperatures. There is a significant positive influence on extreme precipitation when warming is limited to 1.5 °C, compared with a limit of 2 °C. An increase in global warming from 1.5 to 2 °C is projected to lead to an increase in precipitation intensity over China, except for some scattered regions in the northwest and southwest of the country. All annual regional‐mean precipitation events have an apparent linear relationship with global mean temperature, except for CDD. The relationships between daily precipitation extremes and temperature for the present day and for the future show a quadratic polynomial structure, increasing up to 19 °C but decreasing at higher temperatures. In the figure, difference in annual PRCPTOT (a), SDII (b), RX1day (c), RX5day (d), R1mm (e), R10mm (f), R20mm (g), R95p (h), R99p (i), and CDD (j) between 1.5 and 2 °C warming. The dots represent regions where at least 66% of all the models agree on the sign of change in the ensemble mean. [ABSTRACT FROM AUTHOR]

Ji, Yuhe, Liding Chen, and Ranhao Sun, 2012. Temporal and Spatial Variability of Water Supply Stress in the Haihe River Basin, Northern China. Journal of the American Water Resources Association (JAWRA) 48(5): 999-1007. DOI: 10.1111/j.1752-1688.2012.00671.x Abstract: Water resources are becoming increasingly stressed under the influence of climate change and population growth in the Haihe River Basin, Northern China. Assessing the temporal and spatial variability of water supply stress is urgently needed to mitigate water crisis caused by water resource reallocation. Water supply and use data were compiled for the time period of 1998-2003 in this synthesis study. The Water Supply Stress Index (WSSI) as defined as Water Demand/Water Supply was used to quantitate whether water supply could meet the demand of human activities across the study region. We found a large spatial gradient of water supply stress in the study region, being much higher in the eastern subbasins (ranging from 2.56 to 4.31) than the west subbasins (ranging from 0.56 to 1.92). The eastern plain region not only suffered more serious water supply stress but also had a much higher interannual variability than the western hilly region. The uneven spatial distribution of water supply stress might result from the distribution of land use, population, and climate. Future climate change and rapid economic development are likely to aggravate the existing water crisis in the study region. [ABSTRACT FROM AUTHOR]