STUDY ON ACCURACY OF ZTD AND ZWD CALCULATED FROM ERA-INTERIM DATA OVER CHINA
用中国地区ERA-Interim资料计算ZTD和ZWD的精度分析

The zenith tropospheric delay(ZTD) and zenith wet delay(ZWD) derived from the European Center for Medium-Range Weather Forecasts data(ECMWF ZTD/ZWD) were assessed by calculating ZTD/ZWD from GPS observations,and the calculation method was also discussed.The results show that the bias and rms for the ECMWF ZTD are about-1 cm and 2 cm respectively,the absolute values of which for ECMWF ZWD at BJFS and LHAS sites are 1 cm and 1.6 cm respectively.