| タイトル | Assimilation of Freeze - Thaw Observations into the NASA Catchment Land Surface Model |
| 本文（外部サイト） | http://hdl.handle.net/2060/20140012071 |
| 著者（英） | DeLannoy, Gabrielle J. M.; Farhadi, Leila; Kimball, John S.; Reichle, Rolf H. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2014-01-01 |
| 言語 | eng |
| 内容記述 | The land surface freeze-thaw (F-T) state plays a key role in the hydrological and carbon cycles and thus affects water and energy exchanges and vegetation productivity at the land surface. In this study, we developed an F-T assimilation algorithm for the NASA Goddard Earth Observing System, version 5 (GEOS-5) modeling and assimilation framework. The algorithm includes a newly developed observation operator that diagnoses the landscape F-T state in the GEOS-5 Catchment land surface model. The F-T analysis is a rule-based approach that adjusts Catchment model state variables in response to binary F-T observations, while also considering forecast and observation errors. A regional observing system simulation experiment was conducted using synthetically generated F-T observations. The assimilation of perfect (error-free) F-T observations reduced the root-mean-square errors (RMSE) of surface temperature and soil temperature by 0.206 C and 0.061 C, respectively, when compared to model estimates (equivalent to a relative RMSE reduction of 6.7 percent and 3.1 percent, respectively). For a maximum classification error (CEmax) of 10 percent in the synthetic F-T observations, the F-T assimilation reduced the RMSE of surface temperature and soil temperature by 0.178 C and 0.036 C, respectively. For CEmax=20 percent, the F-T assimilation still reduces the RMSE of model surface temperature estimates by 0.149 C but yields no improvement over the model soil temperature estimates. The F-T assimilation scheme is being developed to exploit planned operational F-T products from the NASA Soil Moisture Active Passive (SMAP) mission. |
| NASA分類 | Geophysics |
| レポートNO | GSFC-E-DAA-TN13976 |
| 権利 | Copyright, Distribution as joint owner in the copyright |
|
