Activity #3
Comparing 1 km² Fires to Precipitation (April 1992–Dec 1993)

In this activity, you can view the Earth from the unique perspective of outer space. You will examine monthly snapshots (or global datasets) of our planet’s surface and atmosphere. During this activity, you will investigate complex interaction of the Earth’s fires, both natural and human induced, and preceiptation by looking for patterns and changes over time. You will make connections to global environmental issues.

Background:
These fire data show the number of one square kilometer points, in each half-degree pixel (each pixel is 2500 square kilometers at the equator), that are hot enough to contain a large fire. These data, averaged for each month, are used to monitor natural and man-made fires, which affect both forest ecosystems and global climate. (Data from Advanced Very High Resolution Radiometer [AVHRR]).

Researchers estimate precipitation across the entire globe by considering many different kinds of input data. Rain gauges are the most accurate, but limited to populated land areas. A variety of satellites provide complete global coverage, but they present two major challenges: First, the various satellite sensors only observe quantities related to precipitation, and algorithms must be developed to get the best estimate from each particular sensor. Second, the mix of available data is constantly changing in space and time, forcing researchers to cope with the particular reliabilities and biases at each time/space grid box. The precipitation data set displayed in this loop is computed in the NASA/GSFC Laboratory for Atmospheres as a contribution to the GPCP, an international research project of the World Meteorological Organization’s Global Energy and Water Exchange program.