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Xining, China

Li L.,Qinghai Climate Center | Li L.,Qinghai Center on Climate Change Monitoring and Evaluation | Wang Z.,Qinghai Climate Center | Wang Z.,Qinghai Center on Climate Change Monitoring and Evaluation | And 4 more authors.
Arctic, Antarctic, and Alpine Research | Year: 2010

In this study, we apply temperature, precipitation, and other data from 66 Chinese meteorological stations including Xining and Lhasa to analyze the extreme climate events and their impacting factors over the Qinghai-Tibet Plateau during the period 1961-2007. We focus on the spatial and temporal features of extreme climate events and their long-term changes over five climate zones of alpine grassland, meadow, and desert areas. Results show that, during the past decades, the changes in climate over the Qinghai-Tibet Plateau present trends towards warm and wet conditions. These changes in temperature and precipitation are evident in both seasonal means and extreme events, and the changes in precipitation are apparent in both precipitation amount and number of precipitation days. Clearly, warm and wet events increase, but cold and dry events decrease over the plateau region. Features of the warming climate are relatively consistent in spatial and seasonal distributions, with the most significant changes in winter and autumn and at nighttime. Northern Qinghai exhibits the greatest and most significant decrease in the frequency of extremely low-temperature events. However, the wetting trend shows more distinctive spatial features and is more seasonally dependent. While the trends in both precipitation amount and the number of precipitation days are positive in all climate zones for winter and spring, both positive and insignificant negative trends appear in summer and autumn. The largest decrease in the frequency of severely dry events is found over southeastern Tibet and western Sichuan. © 2010 Regents of the University of Colorado.

Zhang T.-F.,Qinghai Climate Center | Zhang T.-F.,Northwest Normal University | Li L.,Qinghai Climate Center | Liu B.-K.,Institute of Arid Meteorology | And 4 more authors.
Chinese Journal of Ecology | Year: 2014

The standardized precipitation evapotranspiration index (SPEI) is a new climate drought index, which has been proved to be suited to drought monitoring and assessment at different time scales under global warming. This paper, based on SPEI, used the mean monthly temperature and monthly precipitation data from 47 weather stations in Qinghai from 1961-2012, to analyze the spatiotemporal variations of multi-scalar drought risks in the growth season of crop and pasture in Qinghai in the past 52 years. The results showed there was a drying trend during the growth season, and the spatiotemporal variations of drought risks were significant. Under the background of global warming, the drying trend for the early growth stage was slightly weaker than those of the critical water demand stage and the whole growth period. As a result, the key feature of droughts during the growth season was the switch of drought from occurring in the early growth stage to occurring in the critical water demand stage. In addition, drought area showed a significant trend of further expansion. Given an average warming of 1. 36 T over the past 52 years, the drought risk with moderate or higher severities had increased by two times, suggesting a close relationship between the drought and climate change. Thus, climate warming may bring benefits for agriculture, but also increase the instability of agricultural production. © 2014, Editorial Board of Chinese Journal of Ecology. All rights reserved.

Li H.-M.,Qinghai Climate Center | Zhou B.-R.,Institute of Meteorological Science of Qinghai Province | Li L.,Qinghai Climate Center | Wang Z.-Y.,Qinghai Climate Center
Chinese Journal of Ecology | Year: 2011

Based on the 1961-2009 meteorological data from 43 stations and the biomass data from 22 observation points in Qinghai Province as well as the future meteorological data estimated under SRES A1B scenario, this paper verified the applicability of Zhou Guang-sheng' s Model in the province, and, by using this model, calculated the vegetation net primary productivity (NPP) on Qinghai Plateau in 1961-2009, 2020s, 2050s, and 2080s. There was a very good correlation between the calculated and measured NPP values, suggesting the good applicability of Zhou's Model in the province. In 1961-2009, the mean provincial vegetation NPP had an increasing trend, with an increment of 0. 067 t · hm-2 · 10a-1, and the regional vegetation NPP varied greatly, with an increment of 0.077-0. 147 t · hm-2 · 10a-1 in eastern Chaidamu Basin and of 0.006-0.030 t · hm-2 · 10a-1 in most areas of Guoluo. Under the background of climate warming, both the precipitation and the temperature had higher correlations with the NPP, but the influence of precipitation was bigger than that of temperature. In the coming 100 years, the increment of the NPP would be decreased gradually from east to west Qinghai, being 1.35-1.49 t · hm-2 · 100a-1 in east Qinghai and 0.59-0.73 t · hm-2 · 100a-1 in west Qinghai, especially in Chaidamu Basin and Three-River Source Area. In 2020s, 2050s, and 2080s, the vegetation NPP in Qinghai Province would have an increment of 2.5-7.0, 2.7-7.5, and 2.9 -7.8 t · hm-2 · a-1, respectively.

Zhang T.-F.,Qinghai Climate Center | Wang Q.-C.,Qinghai Climate Center | Hu A.-J.,Qinghai Institute of Meteorological science | Wang Z.-J.,Qinghai Climate Center | Shen H.-Y.,Qinghai Climate Center
Chinese Journal of Ecology | Year: 2015

Based on Penman-Monteith model and partial derivatives, this paper analyzed the meteorological and crop data during 1961-2013, to assess the spatial dynamic variation of water deficit of spring wheat at different growth stages in the plateau agricultural region of eastern Qinghai Province. Meanwhile, sensitivity coefficients of the mean temperature, relative humidity, wind speed, and sunshine duration were studied. The result identified an increasing trend of water deficit of spring wheat at each growth stage since 1988. Moreover, the drought degree of spring wheat showed more aggravation during the period between sowing and jointing stages along the line of Guide-Jianzha-Xunhua, the drought degree of spring wheat showed an increasing trend in the period between jointing and heading stages in the regions of "Tongren-Hualong-Minhe", where the change range was the largest. However, a decreasing trend of water deficit was found in most parts of the whole region studied during the period between heading and maturing stages. The profit/loss amount of precipitation in the whole growth stage was the most sensitive variable to sunshine duration. The positively sensitive area to average air temperature was distributed in the valley of Huangshui River, while that to relative humidity, wind speed and sunshine duration was distributed in the northwestern part of eastern Qinghai. The findings from this study provide theoretical guidance on water resources management and regional irrigation scheduling. © 2015, Editorial Board of Chinese Journal of Ecology. All rights reserved.

Li L.,Qinghai Climate Center | Li L.,Qinghai Key Laboratory of Disaster Preventing and Reducing | Shen H.,Qinghai Climate Center | Shen H.,Qinghai Key Laboratory of Disaster Preventing and Reducing | And 5 more authors.
Journal of Geographical Sciences | Year: 2013

In this paper, variations of surface water flow and its climatic causes in China are analyzed using hydrological and meteorological observational data, as well as the impact data set (version 2. 0) published by the National Climate Center in November 2009. The results indicate that surface water resources showed an increasing trend in the source region of the Yangtze River over the past 51 years, especially after 2004. The trend was very clearly shown, and there were quasi-periods of 9 years and 22 years, where the Tibetan Plateau heating field enhanced the effect, and the plateau monsoon entered a strong period. Precipitation notably increased, and glacier melt water increased due to climate change, all of which are the main climatic causes for increases in water resources in the source region. Based on global climate model prediction, in the SRESA1B climate change scenarios, water resources are likely to increase in this region for the next 20 years. © 2013 Science Press and Springer-Verlag Berlin Heidelberg.

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