|
|
 |
|
|
Ann. Geophys., 24, 2781-2792, 2006
www.ann-geophys.net/24/2781/2006/
© European Geosciences Union 2006
A numerical study of cell merger over Cuba – Part I: implementation of the ARPS/MM5 models
D. Pozo1, I. Borrajero2, J. C. Marín1, and G. B. Raga1
1Centro de ciencias de la Atmósfera, UNAM, México, Ciudad Universitaria, México, DF, 04510, México
2Instituto de Meteorología de Cuba, Loma de Casablanca, Regla, C. Habana, Cuba
Abstract. On 21 July 2001 a number of severe storms developed over the region of
Camaguey, Cuba, which were observed by radar. A numerical simulation was
performed in order to realistically reproduce the development of the storms
observed that day. The mesoscale model MM5 was used to determine the
initial, boundary and update conditions for the storm-scale simulation with
the model ARPS. Changes to the source code of ARPS were made in order to
assimilate the output from the MM5 as input data and a new land-use file with
a 1-km horizontal resolution for the Cuban territory was created.
A case representing the merger between cells at different stages of development was
correctly reproduced by the simulation and is in good agreement with radar
observations. The state of development of each cell, the time when the merger
occurred, starting from the formation of clouds, the propagation motion of
the cells and the increase in precipitation, due to the growth of the area
after the merger, were correctly reproduced. Simulated clouds matched the
main characteristics of the observed radar echoes, though in some cases,
reflectivity tops and horizontal areas were overestimated. Maximum
reflectivity values and the heights where these maximum values were located
were in good agreement with radar data, particularly when the model
reflectivity was calculated without including the snow. The MM5/ARPS
configuration introduced in this study, improved sensibly the ability to
simulate convective systems, thereby enhancing the local forecasting of convection
in the region.
Full Article in PDF (1461 KB) |
|
|
