Publication Date:
2021-05-19
Description:
The atmospheric water vapor, a main climatic parameter, remains also one of the less well known in the inter
tropical area. Different space programs have been carried out to improve its measure: the data provided by
these experimental or operational programs, give an alternate and complementary information the model’s
analysis. Moreover, the time series available today, are long enough to allow studies of variability of different
climatic parameters. The following contribution, dedicated to the climate of the Western Africa, analyses the
atmospheric humidity as retrieved by NOAA8/TOVS12 dated over the last 20 years. The climatology of the
upper tropospheric humidity (UTH13), retrieved from HIRS-121, evidences the importance of the position and
the "strength" of dynamic component such as convergence zone, subtropical high: the relative position and the
intensity of the subsidence linked to the St-Helena anticyclone appear as a key parameters for the quality of the
sahelian rainfall season. Moreover, the integrated water vapor content over the Gulf of Guinea, as extracted
from the NVAP9 data base (blended satellite and radiosondes observations) indicates that water vapor
changes slowly; its inertia may be used for trend analysis : excess or deficit of water vapor coincides with wet
or dry rainy season over the Sahel. Computations of water vapor fluxes for the lower levels (coupling the
TOVS humidity to NCEP7 winds), precise the localization of the monsoon fluxes entry over the western
Africa .
Description:
Published
Keywords:
Climate
;
Noaa/Tovs
;
Intertropical convergence zone
;
Subsidence
;
Satellites
;
SSM/I
;
Evaporation
;
Monsoons
Repository Name:
AquaDocs
Type:
Report
,
Non-Refereed
Format:
348500 bytes
Format:
application/pdf
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