المؤلفون: Binhui Liu, Xianguo Lu, Xiangjin Shen, Gaohua Fan

المصدر: Theoretical and Applied Climatology. 130:933-943

مصطلحات موضوعية: Atmospheric Science, 010504 meteorology & atmospheric sciences, 0208 environmental biotechnology, Diurnal temperature variation, 02 engineering and technology, Atmospheric sciences, 01 natural sciences, 020801 environmental engineering, Daily maximum temperature, Climatology, Environmental science, National average, China, 0105 earth and related environmental sciences

الوصف: Based on daily maximum and minimum temperature data from 437 weather stations over China, this study examined the spatiotemporal change of temperature extremes in China from 1960 to 2011. Results showed a general downward trends in the occurrence of cold days (TX10) and nights (TN10) (base period 1961–1990), but upward tendency on the occurrence of warm days (TX90) and nights (TN90), the temperatures of coldest day (TXn), coldest night (TNn), warmest day (TXx), and warmest night (TNx) in China and most climate regions. At the national scale, TX10 and TN10 have significantly decreased by −1.89 and −4.39 days/decade, and TX90 and TN90 have significantly increased by 2.49 and 4.72 days/decade from 1960 to 2011. The national average trends for TXn, TNn, TXx, and TNx were 0.28, 0.54, 0.17, and 0.27 °C/decade, respectively. The temporal changes of extremes indices showed that changes in cold (warm) relative indices may be primarily related to that of corresponding winter (summer) Tmax and Tmin, respectively. Regionally, the magnitudes of changes in extreme indices decreased from the north to south of China. However, we found significant increase of warm extremes, especially warm days and nights in Southeast China. For most climate regions, the trend magnitudes in warm days/nights were larger than that in cold days/nights, but the trend in coldest temperature was much higher than that in warmest temperature. The trend magnitudes in minimum temperature indices were larger than those based on daily maximum temperature, explaining the faster increase of Tmin than Tmax in China.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::43cd8a20411664bb021ec68bdbf6a4b1Test
https://doi.org/10.1007/s00704-016-1934-3Test

المؤلفون: Pujia Yu, Daowei Zhou, Binhui Liu, Guangdi Li, Xiangjin Shen

المصدر: Theoretical and Applied Climatology. 126:141-150

مصطلحات موضوعية: Atmospheric Science, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Steppe, Temperate forest, Climate change, Vegetation, 010501 environmental sciences, Atmospheric sciences, 01 natural sciences, Grassland, Vegetation cover, Temperate climate, Environmental science, Water content, 0105 earth and related environmental sciences

الوصف: The sensitivity of surface air temperature response to different grassland types and vegetation cover changes in the regions of temperate grassland of China was analyzed by observation minus reanalysis (OMR) method. The basis of the OMR approach is that reanalysis data are insensitive to local surface properties, so the temperature differences between surface observations and reanalysis can be attributed to land effects. Results showed that growing-season air temperature increased by 0.592 °C/decade in the regions of temperate grassland of China, with about 31 % of observed warming associated with the effects of grassland types and vegetation cover changes. For different grassland types, the growing-season OMR trend was the strongest for temperate desert steppe (0.259 °C/decade) and the weakest for temperate meadow (0.114 °C/decade). Our results suggest that the stronger intraseasonal changes of grassland vegetation are present, the more sensitive the OMR trend responds to the intraseasonal vegetation cover changes. In August and September, the OMR of temperate meadow showed a weak cooling trend. For temperate meadow, about 72.2 and 72.6 % of surface cooling were explained by both grassland type and increase of vegetation cover for August and September, respectively. For temperate steppe and temperate desert steppe, due to the limited soil moisture and little evaporative cooling feedback, the vegetation changes have no significant effect on the surface air temperature. These results indicate that the impact of grassland types and vegetation cover changes should be considered when projecting further climate change in the temperate grassland region of China.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::6df7efe913814cb5ff313c4926065120Test
https://doi.org/10.1007/s00704-015-1567-yTest