Satellites Play Key Role In Detecting Dangerous Conditions
For the fourth year in a row, NOAA environmental satellites have pinpointed crippling drought conditions in parts of Kenya, Ethiopia and Somalia, leaving area residents on the brink of starvation, water shortages and disease outbreaks, according to the agency's National Environmental Satellite, Data, and Information Service (NOAA Satellite and Information Services).
"Any hope of success for the early stage of the agricultural season (March - May) for that part of Africa is at risk now," said Felix Kogan of the NOAA Satellite and Information Services Office of Research and Applications in Camp Springs, Md. "This is the time that the local population counts on to get enough food to last until fall, when the next harvest is ready."
Kogan added, "Drought that hangs on this long anywhere is very unusual. We want to give humanitarian and relief officials advanced notice to make decisions that hopefully will save lives."
"NOAA's ability to use data from our environmental satellites to detect these dangerous conditions is a striking example of the benefits derived from a global observing system. Our satellite data combined with in-situ observations across air, land and water for climate will give us the tools we need to take the pulse of the planet," said retired Navy Vice Adm. Conrad C. Lautenbacher, Ph.D., undersecretary of commerce for oceans and atmosphere and NOAA administrator.
Satellite Data Crucial
Information from NOAA's polar-orbiting environmental satellites (POES) helped researchers track the ongoing drought conditions. POES constantly circle the Earth in orbits that provide two views each day of the entire Earth and support NOAA's large-scale, long-range weather and climate forecasts and other missions. (Click NOAA satellite image for larger view of vegetation health in the Horn of Africa over several years. Please credit "NOAA.")
One of the satellites' key instruments, called the Advanced Very High Resolution Radiometer (AVHRR), measures the amount of solar reflection from green vegetation based on their chlorophyll content. Chlorophyll, the green pigment in plants, transforms energy from sunlight into chemical energy.
The more solar energy plants absorb means less energy reflected back into space. The reflected energy - or radiance - is measured by the AVHRR sensor. Kogan said NOAA Satellite and Information Services researchers combine the POES visible, near infrared and infrared measurements to develop several indices to calculate moisture, thermal conditions and the overall health of the vegetation.
"Since 2000, drought conditions have affected nearly 20 percent of the world's land mass," Kogan added. "This method has proven successful over the years, and we'll continue using it as a way to warn the global community about the dangers of long-term drought."
NOAA Satellite and Information Services is the nation's primary source of space-based meteorological and climate data. It operates the nation's environmental satellites, which are used for weather and ocean observation and forecasting, climate monitoring and other environmental applications. Some of the applications include sea-surface temperature, fire detection and ozone monitoring.
NOAA Satellite and Information Services also operates three data centers, which house global databases in climatology, oceanography, solid Earth geophysics, marine geology and geophysics, solar-terrestrial physics and paleoclimatology.
NOAA is dedicated to enhancing economic security and national safety through the prediction and research of weather and climate-related events and providing environmental stewardship of the nation's coastal and marine resources. NOAA is part of the U. S. Department of Commerce.