Evaluation of Surface Meteorological Elements from Several Numerical Models in China

The applicability of surface meteorological elements such as surface air temperature, relative humidity, and wind speed from the European Centre for Medium-Range Weather Forecasts (ECMWF), Japan Meteorological Agency (JMA), and Global Forecast System (GFS) is evaluated in China by comparison with automatic observations from 2421 stations reported by the Chinese Meteorological Administration from 1 July 2010 to 30 June 2013. The results indicate that the three numerical models can essentially display spatiotemporal consistence with observation and that their performance in East China is more reliable than that in the western area. The various surface meteorological variables of the numerical models are key to these differences. For example, the surface air temperature and relative humidity of ECMWF are closer to the observations than the JMA and GFS. Moreover, the qualities of surface air temperature and relative humidity from both ECMWF and JMA are better in the analysis field than those in prediction field. In addition, for surface air temperature, the largest differences with observation are noted with ECMWF and JMA in winter and GFS in summer. For surface relative humidity, the discrepancy of the three numerical models is the most significant in autumn and in winter. For the surface wind speed from these numerical models, JMA is the closest to the observation in eastern China, whereas ECMWF is the best in northern and western China. However, from the perspective of time, the differences among JMA, GFS, and the observations are the most obvious in winter.