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Sun L.,Institute of Meteorological science of Jilin Province | Sun L.,Wuhan Institute of Heavy Rain | Sun L.,Latitude | Shen B.,Institute of Meteorological science of Jilin Province | And 3 more authors.
Advances in Atmospheric Sciences | Year: 2010

The characteristics of moisture transport and budget of widespread heavy rain and local heavy rain events in Northeast China are studied using the NCEP-NCAR reanalysis 6-hourly and daily data and daily precipitation data of 200 stations in Northeast China from 1961-2005. The results demonstrate that during periods with widespread heavy rain in Northeast China, the Asian monsoon is very active and the monsoonal northward moisture transport is strengthened significantly. The widespread heavy rainfall obtains enhanced water vapor supply from large regions where the water vapor mainly originates from the Asian monsoon areas, which include the East Asian subtropical monsoon area, the South China Sea, and the southeast and southwest tropical monsoon regions. There are several branches of monsoonal moisture current converging on East China and its coastal areas, where they are strengthened and then continue northward into Northeast China. Thus, the enhanced northward monsoonal moisture transport is the key to the widespread heavy rain in Northeast China. In contrast, local heavy rainfall in Northeast China derives water vapor from limited areas, transported by the westerlies. Local evaporation also plays an important role in the water vapor supply and local recycling process of moisture. In short, the widespread heavy rains of Northeast China are mainly caused by water vapor advection brought by the Asian monsoon, whereas local heavy rainfall is mainly caused by the convergence of the westerly wind field. © 2010 Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag Berlin Heidelberg.

Chen Z.,Wuhan Institute of Heavy Rain | Chen Z.,Wuhan Region Climate Center
Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering) | Year: 2010

Using the yearly series of maximum 10 min averaged wind velocity observed by Yuyang weather stations from 1952 to 2000, the gale characteristics of Yuyang weather stations was analyzed. The reference wind velocity and design wind velocity were calculated by adopting the function of Extreme I and referencing the observed wind datum along Yangtze River nearby bridge location. Several conclusions are listed as following: (1) the bridge location takes EN wind as dominant wind direction and extreme value of maximum 10 min wind velocity is 24.7 m/s. (2) The annually averaged maximum 10 min wind velocity of the 10 meter high for different return periods(100, 50, 30, 10 year) are respectively 27.6 m/s, 25.4 m/s, 23.8 m/s and 20.2 m/s. (3) the averaged maximum 10 min wind velocity of the 10 meter high of bridge location for different return periods(100, 50, 30, 10 year) are respectively 29.0 m/s, 26.7 m/s, 25.0 m/s and 21.2 m/s. Finally, the design reference wind speed of every 10 m layer within 300 m high is extrapolated by using the index change of wind velocity in the surface layer changed by the height, which can be referred for design and construction of the bridge.

Shi P.,Chinese Academy of Fishery Sciences | Chen Z.,Wuhan Institute of Heavy Rain | Yang Q.,Jiangxi Agricultural University | Harris M.K.,Texas A&M University | Xiao M.,Wuhan University
Ecology and Evolution | Year: 2014

Climate change is expected to have a significant effect on the first flowering date (FFD) in plants flowering in early spring. Prunus yedoensis Matsum is a good model plant for analyzing this effect. In this study, we used a degree day model to analyze the effect of air temperatures on the FFDs of P. yedoensis at Wuhan University from a long-time series from 1951 to 2012. First, the starting date (=7 February) is determined according to the lowest correlation coefficient between the FFD and the daily average accumulated degree days (ADD). Second, the base temperature (=-1.2°C) is determined according to the lowest root mean square error (RMSE) between the observed and predicted FFDs based on the mean of 62-year ADDs. Finally, based on this combination of starting date and base temperature, the daily average ADD of every year was calculated. Performing a linear fit of the daily average ADD to year, we find that there is an increasing trend that indicates climate warming from a biological climatic indicator. In addition, we find that the minimum annual temperature also has a significant effect on the FFD of P. yedoensis using the generalized additive model. This study provides a method for analyzing the climate change on the FFD in plants' flowering in early spring. © 2013 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.

Zhang L.-P.,Wuhan University | Zhang L.-P.,Wuhan Institute of Heavy Rain | Qin L.-L.,Wuhan University | Hu Z.-F.,Beijing Water Utilities Bureau of Haidian District | Zeng S.-D.,Wuhan University
Shuili Xuebao/Journal of Hydraulic Engineering | Year: 2010

The change of surface water resources in the water source area of the Middle Route of South-to-North Water Diversion Project in the future will directly affect the reliability of the whole project. It is an important basis for trans-valley water resources deployment and management. Based on the digital elevation model, land used information and soil type data in the water source area of the Project, the applicability of the SWAT model in this basin is investigated by using the observation data obtained from 1980 to 1987 to calibrate the parameters of the model. According to the Fourth Assessment Report of multi-mode climate model results for the Intergovernmental Panel on Climate Change, the responsed precipitation, air temperature, runoff and evaporation under different Special Report on Emissions Scenarios in the 21st Century is analyzed. Compared with the baseline period, The analysis results show that the temperature and the annual precipitation will continue to increase, but the runoff in the catchment will be reduced at first and then increased, the runoff will begin to increase in the forties of the 21st Century. The result indicates that the water resources will reduce in the early 21st Century and will increase in the mid-late. The future climate change will have a little influence on the runoff of the water source area, and thus will generally be favorable to the South-to-North Water Transfer Project.

Ma Z.-Y.,Jiangxi Meteorological Science Institute | Zhang Y.,Wuhan Institute of Heavy Rain | Ma X.-L.,Lushan Meteorological Bureau | Ye X.-F.,Pingxiang Meteorological Bureau | And 2 more authors.
Journal of Natural Disasters | Year: 2010

By means of routine synoptic charts, meso - scale analysis charts, satellite cloud pictures and radar echo pictures, triggering system and forming mechanism of convective storm in Jiangxi were preliminary analyzed and summarized with case study method. Results show that the influential factors including cold front, stationary front, shear(850Hpa) , energy front(850Hpa) , meso-convective clusters, meso-topography convergence line, cold storm stack, cold effluent border and local frontal zone are mainly the storm triggering system and forming mechanism.

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