Elements for Life

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describe the data and processes that FEWS NET uses to provide

decision support.

Remote sensing in FEWS NET analytical processes

Biophysical data provides information on the yields of the food

production equation, and threats to pastoral resources and ulti-

mately to the agricultural economy as a whole. To identify

abnormally wet or dry periods, FEWS NET relies on data on

vegetation, temperature, and rainfall derived from remote sensing

and local measurements when they are available. Currently, the

FEWS NET early warning function begins with a weekly assess-

ment process that includes members of NASA, NOAA, USGS,

USDA, USAID, the University of California at Santa Barbara

(UCSB), and a variety of technical specialists in Africa, Central

America, and Afghanistan. The data includes precipitation gauges

and gridded data from merged satellite models; vegetation data

from the Advanced Very Hight Resolution Radiometer (AVHRR),

Système Pour l’Observation de la Terre (SPOT), MODIS and

Landsat; gridded cloudiness products; global climate indicators;

precipitation forecasts (24-72 hours); modelled soil moisture;

gridded fire products; snow extent products; hydrological models

for flood forecasting; and seasonal forecasts.

Rainfall has been used extensively to drive many models,

but rainfall measurements are notoriously prone to errors.

Errors can occur in approximating the degree of cloudiness,

the amount of rain that has fallen from these clouds, the inten-

sity of the rainfall, the impact of topography on rainfall, the

sensitivity to the density of the rainfall measurements and accu-

racy of local rainfall gauge measurements, and other effects

which result in significant random error and non-negligible

bias.

Fortunately, scientists have found a much more stable

proxy for rainfall measurement. In addition to making rainfall

and analysis, FEWS NET decision support and reporting are

carried out primarily by a USAID contractor which employs

most of the social scientists involved in the project, as well as

the FEWS NET local representatives in the field. Data prod-

ucts and dissemination mechanisms are focused on ensuring

that effective products are developed and the right people see

them promptly. By defining FEWS NET’s primary audience as

local decision makers, locally relevant, actionable policy infor-

mation is generated which can then be disseminated to

audiences at a variety of decision-making levels – local,

regional, and international.

Linking early warning activities to effective intervention

requires both short- and long-term actions.

Short-term response

to an identified hazard involves preparedness and contingency

planning that allow immediate response to the situation. FEWS

NET has become increasingly involved in contingency planning

as a method of generating relationships with local government

actors and decision makers who are the audience for its products

and therefore must be involved in any determination of and

response to crisis conditions.

Participation of local decision

makers, national government agencies, and non-governmental

personnel is critical to achieving FEWS NET’s goal of reducing

the loss of lives and livelihoods during food crises. Contingency

planning and the strengthening of networks of decision makers

will ultimately reduce overall vulnerability to these climatic

hazards.

Food security has three main components: food availability,

food access, and food utilization. FEWS NET focuses on collect-

ing data on food availability from biophysical parameters and

food access through socio-economic datasets. Other organiza-

tions investigate food utilization, for example the individual’s

ability to use the food they eat effectively. The next two sections

Vegetation data anomaly from MODIS for southern Africa, from 19 Dec 2006 – 03 Jan 2007

Source: NASA