Skip to Main content Skip to Navigation
Journal articles

Driftsonde observations to evaluate numerical weather prediction of the late 2006 African monsoon

Abstract : During the international African Monsoon Multidisciplinary Analysis (AMMA) project, stratospheric balloons carrying gondolas called driftsondes capable of dropping meteorological sondes were deployed over West Africa and the tropical Atlantic Ocean. The goals of the deploymentwere to test the technology and to study the African easterly waves, which are often the forerunners of hurricanes. Between 29 August and 22 September 2006, 124 sondes were dropped over the seven easterly waves that moved across Africa into the Atlantic between about 10° and 20°N, where almost no in situ vertical information exists. Conditions included waves that developed into Tropical Storm Florence and Hurricanes Gordon and Helene. In this study, a selection of numerical weather prediction model outputs has been compared with the dropsondes to assess the effect of some developments in data assimilation on the quality of analyses and forecasts. By comparing two different versions of the Action de Recherche Petite Echelle Grande Echelle (ARPEGE) model of Météo-France with the dropsondes, first the benefits of the last data assimilation updates are quantified. Then comparisons are carried out using the ARPEGE model and the Integrated Forecast System (IFS) model of the European Centre for Medium-Range Weather Forecasts. It is shown that the two models represent very well the vertical structure of temperature and humidity over both land and sea, and particularly within the Saharan air layer, which displays humidity below 5%-10%. Conversely, the models are less able to represent the vertical structure of the meridional wind. This problem seems to be common to ARPEGE and IFS, and its understanding still requires further investigations. © 2013 American Meteorological Society.
Document type :
Journal articles
Complete list of metadata

https://hal.archives-ouvertes.fr/hal-01092183
Contributor : Denis Roura Connect in order to contact the contributor
Submitted on : Monday, October 25, 2021 - 9:24:10 AM
Last modification on : Wednesday, November 17, 2021 - 12:27:07 PM

File

[15588432 - Journal of Applied...
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Philippe Drobinski, F. Karbou, P. Bauer, P. Cocquerez, C. Lavaysse, et al.. Driftsonde observations to evaluate numerical weather prediction of the late 2006 African monsoon. Journal of Applied Meteorology and Climatology, American Meteorological Society, 2013, 52 (4), pp.974-995. ⟨10.1175/jamc-d-11-0176.1⟩. ⟨hal-01092183⟩

Share

Metrics

Record views

458

Files downloads

48