American Meteorological Society;Washington: American Meteorological Society
摘要:
摘要： AbstractGlobal positioning system (GPS) radio occultation (RO) data have been broadly used in global and regional numerical weather predictions. Assimilation with the bending angle often performs better than refractivity, which is inverted from the bending angle under spherical assumption and is sometimes associated with negative biases at the lower troposphere; however, the bending angle operator also requires a higher model top as used in global models. This study furnishes the feasibility of bending-angle assimilation in the prediction of heavy precipitation systems with a regional model. The local RO operators for simulating bending angle and refractivity are implemented in the Weather Research and Forecasting (WRF)–local ensemble transform Kalman filter (LETKF) framework. The impacts of assimilating RO data from the Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC) using both operators are evaluated on the prediction of a heavy precipitation episode during Southwest Monsoon Experiment intensive observing period 8 (SoWMEX-IOP8) in 2008. Results show that both the refractivity and bending angle provide a favorable condition for generating this heavy rainfall event. In comparison with the refractivity data, the advantage of assimilating the bending angle is identified in the midtroposphere for deepening of the moist layer that leads to a rainfall forecast closer to the observations. 出版者： Washington: American Meteorological Society 出版日期： 2014-11-01 出處： Monthly Weather Review, 2014-11, Vol.142 (11), p.4139-4163 資源來源： EBSCOhost OmniFile Full Text Select 版權： Copyright American Meteorological Society Nov 2014 版權： Copyright American Meteorological Society 2014 識別號： ISSN: 0027-0644 識別號： ISSN: 1520-0493 識別號： EISSN: 1520-0493 識別號： DOI: 10.1175/mwr-d-13-00275.1 識別號： CODEN: MWREAB
