“Many people said it would never get off the ground; some said it wouldn’t last a year,” notes NASA ocean scientist Gene Carl Feldman. “The mission was planned for five years. We got 13 years of incredible data out of this amazing little satellite.”
The Sea-viewing Wide Field-of-view-Sensor, or SeaWiFS, ran from 1998 to 2010 and took one simple but elegant measurement; how “green” is the Earth?
Green being how much chlorophyll—the pigment that helps turn sunlight into organic energy for plants—is present in the seas and on land, not how “green” we are; actual green. And the above image is the answer to the question, and it looks absolutely stunning.
The image is a representation of the global average of the 13 years that SeaWiFS ran. For the oceans, the colors represent the concentration of chlorophyll and indicate where phytoplankton most often bloomed since 1998. On the land, data are depicted as a Normalized Difference Vegetation Index (NDVI), which shows the density of green vegetation. An NDVI of zero means no green plants and a high value (0.8 or 0.9) is a thick canopy of green leaves.
“There is no question that the Earth is changing,” said Feldman, SeaWiFS project manager at NASA’s Goddard Space Flight Center. “SeaWiFS enabled us for the first time to monitor the biological consequences of that change—to see how the things we do, and how natural variability, affect the Earth’s ability to support life.”
Source: NASA Earth Observatory