Poster Sessions
P-21 |
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Ensemble-based observation impact estimates using an observation-based verification norm |
Martin Weissmann (Hans-Ertel Centre for Weather Research, LMU Munich), |
| Abstract |
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Knowledge on the contribution of various observations and observing systems is crucial for the refinement of observing networks and data assimilation systems. This poster presents a novel approach for estimating observation impact in ensemble-based data assimilation and forecasting systems and its application to the experimental, convective-scale ensemble system of Deutscher Wetterdienst. Instead of the subsequent analysis, it uses subsequent observations for verification that are considerably more independent from the forecast. Furthermore, a peculiar property in the probability distribution of observation impact is used to define a measure for the accuracy of the impact assessment. Applying this method to a three-day test period shows that a well-defined observation impact value can be assigned to most observation groups. |