| タイトル | Radiance Assimilation Shows Promise for Snowpack Characterization: A 1-D Case Study |
| 著者（英） | Margulis, Steve; Durand, Michael; Kim, Edward |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2008-12-15 |
| 言語 | eng |
| 内容記述 | We demonstrate an ensemble-based radiometric data assimilation (DA) methodology for estimating snow depth and snow grain size using ground-based passive microwave (PM) observations at 18.7 and 36.5 GHz collected during the NASA CLPX-1, March 2003, Colorado, USA. A land surface model was used to develop a prior estimate of the snowpack states, and a radiative transfer model was used to relate the modeled states to the observations. Snow depth bias was -53.3 cm prior to the assimilation, and -7.3 cm after the assimilation. Snow depth estimated by a non-DA-based retrieval algorithm using the same PM data had a bias of -18.3 cm. The sensitivity of the assimilation scheme to the grain size uncertainty was evaluated; over the range of grain size uncertainty tested, the posterior snow depth estimate bias ranges from -2.99 cm to -9.85 cm, which is uniformly better than both the prior and retrieval estimates. This study demonstrates the potential applicability of radiometric DA at larger scales. |
| NASA分類 | Earth Resources and Remote Sensing |
| 権利 | Copyright |
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