NAME =  Pingping Xie  
ORGANIZATION =  NOAA/NWS Climate Prediction Center  
ADDRESS =  5200 Auth Road, #605, Camp Springs, MD 20746  
COUNTRY =  USA  
PHONE =  1-301-763-8000, Ext. 7572  
FAX =  1-301-763-8125  
E-MAIL =  Pingping.Xie@noaa.gov  
POSTER_ONLY =  no  
THEME =  T2  
DATE =  13-Jul-04-03:17:43  
ABSID = T2PX13Jul04031743 
TITLE = An Analysis of Daily Precipitation Over East Asia: Current Status and Future Improvements 
AUTHOR_1 = Pingping Xie 
INSTITUTION_1 = NOAA/NWS Climate Prediction Center 
AUTHOR_2 = Akiyo Yatagai 
INSTITUTION_2 = Research Institute for Humanity and Nature (RIHN) 
PRESENTER = AUTHOR_2 
AUTHOR_3 = Mingyue Chen 
INSTITUTION_3 = Noaa/NWS Climate Prediction Center 
AUTHOR_4 = Tadahiro Hayasaka 
INSTITUTION_4 = Research Institute for Humanity and Nature (RIHN) 
AUTHOR_5 = Yoshihiro Fukushima 
INSTITUTION_5 = Research Institute for Humanity and Nature (RIHN) 
AUTHOR_6 = Changming Liu 
INSTITUTION_6 = Institute of Geography, CAS 
ABSTRACT = As part of the Yellow River Project, an analysis of daily precipitation has been constructed on a 0.5 deg lat/lon grid over East Asia [70E-140E; 5N-60N] for a 42-year period from 1961 to 2002 by interpolating station observations at over 2000 gauges collected from several individual sources. First, daily climatology is defined for each station as the summation of the first 6 hamonics for the 365-calendar-day time series of the mean daily values over a 20-year period from 1978 to 1997.  Analyzed fields of daily precipitation are then created by interpolating the station climatology through the algorithm of Shepard (1965).  To account for the orographic effects, these fields are then adjusted by the PRISM monthly precipitation climatology of Daly et al. (1994) so that the monthly accumulation of the adjusted daily climatology meets that of the PRISM while temporal variation patterns in the original time series are retained. Meanwhile, gridded values of ratio to climatology is computed by interpolating the corresponding station values through the Optimal Interpolation (OI) technique. Analyses of total daily precipitation are finally calculated by multiplying the daily climatology with the ratio.
 
Quality of the daily precipitation analysis depends primarily on the density of gauge networks. In the current version of our analysis, gauge observations from over 1500 stations are available over China, ensuring high accuracy especially over the region along the Yellow River where daily reports are available from ~700 stations. Outside the chinese board, however, only precipitation reports from the Global Telecommunication Systems (GTS) are included to define the daily analyses. Further improvements are underway to collect and use station observations from additional information sources, such as the GAME-T data sets and other individual collections. Your collaboration is highly appreciated both in applications of this new precipitation analysis and in potential contribution of gauge observations over any portion of our target domain.