The paper investigates the possibility of integrating satellite observations and limited-area atmospheric model simulations in the study of the meso-scale processes in the Mediterranean Sea. A tropical-like cyclone, which occurred on 9 and 10 December 1996 over the central Mediterranean Sea, has been used as a case study. The main features of the cyclone, derived from satellite wind and vertically integrated liquid water content (LWC) fields, have been compared with the results of a limited-area model, obtained with and without scatterometer data assimilation. The results indicate an acceptable comparability of the wind fields, despite the model-scatterometer wind bias and the misplacement of the cyclone position in the simulations. The vertically integrated quantities, such as the LWC and the model vertically integrated cloud mixing ratio (CWINT), do not show the same degree of comparability. This is because they reflect only large-scale features, whereas the meso-scale features are only detected by the satellite observations. As expected, the results of assimilating the scatterometer data into the model show an improvement over the cyclone positioning but do not provide a better description of its mesoscale features. The lack of improvement in the determination of the CWINT horizontal structure after scatterometer data assimilation indicates the need to assimilate the LWC fields in future studies.
Intercomparison of satellite observations and atmospheric model simulations of a meso-scale cyclone in the Mediterranean Sea
Zecchetto S;De Biasio F;
2002
Abstract
The paper investigates the possibility of integrating satellite observations and limited-area atmospheric model simulations in the study of the meso-scale processes in the Mediterranean Sea. A tropical-like cyclone, which occurred on 9 and 10 December 1996 over the central Mediterranean Sea, has been used as a case study. The main features of the cyclone, derived from satellite wind and vertically integrated liquid water content (LWC) fields, have been compared with the results of a limited-area model, obtained with and without scatterometer data assimilation. The results indicate an acceptable comparability of the wind fields, despite the model-scatterometer wind bias and the misplacement of the cyclone position in the simulations. The vertically integrated quantities, such as the LWC and the model vertically integrated cloud mixing ratio (CWINT), do not show the same degree of comparability. This is because they reflect only large-scale features, whereas the meso-scale features are only detected by the satellite observations. As expected, the results of assimilating the scatterometer data into the model show an improvement over the cyclone positioning but do not provide a better description of its mesoscale features. The lack of improvement in the determination of the CWINT horizontal structure after scatterometer data assimilation indicates the need to assimilate the LWC fields in future studies.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.