One day estimates of accumulated precipitation for the
African continent are prepared operationally at the Climate Prediction Center (CPC) for the
United States Agency for International Development (USAID)
as a part of the Famine Early Warning System Network (FEWS NET).
These estimates are archived and disseminated by the United States Geological Survey (
USGS) from the Earth Resources Observation Systems (
EROS) Data Center to assist in drought
monitoring efforts for the sub-Saharan portion of the African continent.
Due to the less than optimal density of the rain gauge
network over the African continent, precipitation is not adequately measured,
necessitating the use of a statistical algorithm for precipitation estimation. The method
utilized by the CPC augments the available surface data with remotely sensed data in order
to produce estimates of accumulated precipitation.
Along with daily, weekly, 10-day, and monthly precipitation estimates for the Africa region, the Climate
Prediction Center's FEWS-NET staff monitor meteorological and climatic phenomena for the continent. Monitoring
includes dryness, drought, flooding, temperature extremes, cyclones, and organized storm systems, to name a few.
A weekly weather hazards product is disseminated to give users early information that may be help to make more
accurate, relevant decisions.
A cyclone monitoring project has been implemented to track potentially devestating storm systems as they approach Africa
from the Indian Ocean. On a daily basis, relevant storm positional information is relayed to the CPC FEWS-NET group
from the Joint Typhoon Warning Center and scripted using GIS technology. The result is a daily-updating cyclone track
and forecast graphic for any active storms threatening Africa. This product is disseminated via email and internet
to interested parties.
High resolution gridded forecasts have been implemented for the African continent to give meteorological forecasts
out to three days in advance. While not extremely useful for climate monitoring, these modeled outputs enable
monitoring of local, hydrological issues. Experimentation has begun to compare this data with rainfall estimates and
other forecast products.
During the Sahelian monsoon season, normally running from April-October, the African Intertropical Convergence Zone is monitored and
dekadal analyses are performed. Monitoring has been ongoing since 1988 and a useful climatology is now available to comapre
current conditions with the norm.
ITCZ monitoring, as with all CPC FEWS-NET projects, is performed via a close relationship with the CPC African Desk. This
interaction is a crucial aspect of the CPC FEWS-NET program.