The impact of atmospheric heat sources over the eastern Tibetan Plateau and the tropical western Pacific on the summer rainfall over the Yangtze-River basin

2006 ◽  
Vol 23 (1) ◽  
pp. 149-155 ◽  
Author(s):  
Maoqiu Jian ◽  
Yunting Qiao ◽  
Zhuojian Yuan ◽  
Huibang Luo
2019 ◽  
Vol 34 (3) ◽  
pp. 705-717
Author(s):  
Zhenkuan Su ◽  
Michelle Ho ◽  
Zhenchun Hao ◽  
Upmanu Lall ◽  
Xun Sun ◽  
...  

2012 ◽  
Vol 610-613 ◽  
pp. 1070-1077
Author(s):  
Guang Wen Ma ◽  
Xiang Bao ◽  
Ye Yao Wang

Base on estimate the amount of nitrogen (N) added to the agroecosystem by human activities, and analyze changes in the environment influence of excess N and fertilizer nitrogen use efficiency (FNE) in agricultural fields of the Yangtze River Basin between 1990 and 2000. Excess N is stored in farmland and transferred to water bodies. The excess N stored in farmland was 2.75 Tg N in 1990 and 3.88 Tg N in 2000. The total N transferred to water bodies was 3.45 Tg N in 1990 and 5.07 Tg N in 2000. The FNE decreased by 22.17 % from 1990 to 2000. Changes in the geographic distribution of variational trends of the N budget, N transferred to water bodies, and FNE are more pronounced in the middle and lower reaches of the Yangtze River Basin. We propose effective measures for maximizing the efficiency of N use and reducing the impact of agricultural N on environment in the Yangtze River Basin.


2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Ziwei Xiao ◽  
Peng Shi ◽  
Peng Jiang ◽  
Jianwei Hu ◽  
Simin Qu ◽  
...  

A better understanding of the runoff variations contributes to a better utilization of water resources and water conservancy planning. In this paper, we analyzed the runoff changes in the Yangtze River Basin (YRB) including the spatiotemporal characteristics of intra-annual variation, the trend, the mutation point, and the period of annual runoff using various statistical methods. We also investigated how changes in the precipitation and temperature could impact on runoff. We found that the intra-annual runoff shows a decreasing trend from 1954 to 2008 and from upper stream to lower stream. On the annual runoff sequence, the upstream runoff has a high consistency and shows an increasing diversity from upper stream to lower stream. The mutation points of the annual runoff in the YRB are years 1961 and 2004. Annual runoff presents multitime scales for dry and abundance changes. Hurst values show that the runoffs at the main control stations all have Hurst phenomenon (the persistence of annual runoff). The sensitivity analyses of runoff variation to precipitation and temperature were also conducted. Our results show that the response of runoff to precipitation is more sensitive than that to temperature. The response of runoff to temperature is only one-third of the response to precipitation. A decrease in temperature may offset the impact of decreasing rainfall on runoff, while an increase in both rainfall and temperature leads to strongest runoff variations in the YRB.


2020 ◽  
Author(s):  
Wei Li ◽  
Lu Li ◽  
Jie Chen ◽  
Qian Lin ◽  
Hua Chen

Abstract. Land use and cover has been significantly changed all around the world during the last decade. In particular, the Returning Farmland to Forest Program (RFFP) have resulted in significant changes in regional land use and cover, especially in China. The land use and cover change (LUCC) may lead to the change in regional climate. In this study, we take the Yangtze river basin as a case study and analyze the impacts of LUCC and reforestation on summer rainfall amount and extremes based on the Weather Research and Forecasting model. Firstly, two observed land use and cover scenarios (1990 and 2010) were chosen to investigate the impacts of LUCC on the summer rainfall during the last decade. Secondly, two hypothetical reforestation scenarios (i.e., scenarios of 20 % and 50 % cropland changed to be forest) were taken based on the control year of 2010 to test the sensitivity of summer rainfall (amount and extremes) to reforestation. The results showed that LUCC between 1990 and 2010 decreased average summer rainfall, while increased extreme summer daily rainfall in the Yangtze River basin. The extreme summer daily rainfall increased up to 50 mm, which was mainly observed in the midstream and downstream. Reforestation could increase summer rainfall amount and extremes, and the effects were more pronounced at the local scale where suffered reforestation than at the whole basin. Moreover, the effects of reforestation were influenced by the reforestation proportion. In this study, the average summer rainfall increased more for the scenario of 20 % croplands changed to forests than that for the scenario of 50 %, while the high-intensity short-duration rainfall increased more for the scenario of 50 % croplands changed to forests than that for the scenario of 20 %. Although a comprehensive assessment of the impacts of LUCC on summer rainfall amount and extremes was conducted, further studies are needed to better investigate the uncertainty.


Sign in / Sign up

Export Citation Format

Share Document