In this study,the performances of the Community Atmosphere Model(CAM)and Pleim–Xiu(PX)surface layer parameterization schemes are investigated by using field observations.The parameterization schemes are evaluated aga...In this study,the performances of the Community Atmosphere Model(CAM)and Pleim–Xiu(PX)surface layer parameterization schemes are investigated by using field observations.The parameterization schemes are evaluated against continuous momentum and sensible heat flux observations measured at two flat and homogeneous grassland sites in the suburb of Nanjing,eastern China.The observations were conducted from 30 December 2014 to 18 April 2017 at Jiangxinzhou and from 9 February 2015 to 26 March 2018 at Jiangning.It is found that the momentum flux is overall in good agreement with the observation,and the sensible heat flux is overestimated.The parameterizations of the momentum and sensible heat fluxes well capture the diurnal and seasonal patterns seen in the observations at the two sites.At Jiangxinzhou,the PX parameterization underestimates the momentum flux throughout the day and the CAM parameterization slightly overestimates it around the noon,while they underestimate the momentum flux throughout the year.The two parameterizations overestimate the sensible heat flux in the daytime as well as over the entire year.At Jiangning,the two parameterizations overestimate the momentum flux throughout the day and the sensible heat flux in the daytime,and overestimate both of them over the entire year.The two parameterizations are not significantly different from each other in reproducing the turbulent fluxes at the same site,while they perform differently at the two sites in terms of statistics.In addition,the parameterized fluxes increase with increased roughness length.展开更多
基金Supported by the National Natural Science Foundation of China(41375075)Meteorological Collaborative Innovation Foundation in Huadong Area(QYHZ201604)National Key Research and Development Program of China(2017YFC1502104)
文摘In this study,the performances of the Community Atmosphere Model(CAM)and Pleim–Xiu(PX)surface layer parameterization schemes are investigated by using field observations.The parameterization schemes are evaluated against continuous momentum and sensible heat flux observations measured at two flat and homogeneous grassland sites in the suburb of Nanjing,eastern China.The observations were conducted from 30 December 2014 to 18 April 2017 at Jiangxinzhou and from 9 February 2015 to 26 March 2018 at Jiangning.It is found that the momentum flux is overall in good agreement with the observation,and the sensible heat flux is overestimated.The parameterizations of the momentum and sensible heat fluxes well capture the diurnal and seasonal patterns seen in the observations at the two sites.At Jiangxinzhou,the PX parameterization underestimates the momentum flux throughout the day and the CAM parameterization slightly overestimates it around the noon,while they underestimate the momentum flux throughout the year.The two parameterizations overestimate the sensible heat flux in the daytime as well as over the entire year.At Jiangning,the two parameterizations overestimate the momentum flux throughout the day and the sensible heat flux in the daytime,and overestimate both of them over the entire year.The two parameterizations are not significantly different from each other in reproducing the turbulent fluxes at the same site,while they perform differently at the two sites in terms of statistics.In addition,the parameterized fluxes increase with increased roughness length.
