All plant life on Earth has been photographed and a new mosaic image shows our world without oceans or clouds, revealing Earth as the Green Planet. This is the most-detailed image ever taken of plant life on the Earth as seen from space.
The original images were created from photographs taken over the course of an entire year, from April 2012 to April 2013. They were taken with the Visible-Infrared Imager/Radiometer Suite (VIIRS) instrument aboard the Suomi NPP satellite. Water from the planet's oceans and seas, which make up three-quarters of the surface of our world, were digitally removed to highlight the plant cover.
Different shades of green in the image represent various conditions in vegetation. Plant life is thinnest in light areas, while it is densest in the dark-green areas.
The $1.5 billion-dollar Suomi NPP (National Polar Orbiting Partnership) satellite took the images from its orbit, sailing 512 miles above the surface of the planet. It collects a total of 330 megabytes of photographs every week while studying the planet. By measuring the reflectivity of vegetation, astronomers can get a good measurement of the health of plant cover on the ground. This works because of photosynthesis. Plants absorb visible light in order to feed chemical reactions, and reflect near-infrared light. Because of this, less visible and more near-infrared light is reflected from plants than from bare ground or urban sprawl.
Each one of the pixels in the image is about 1,640 feet across, and a change of even a single pixel in pictures from the Suomi observatory could signal a forest fire of the beginning of deforestation. Such a change can even herald the start of a malaria outbreak.
"As vegetation grows in sub-Saharan Africa, so does the risk for malaria. Vegetation indexes provide world health organizations the lead time needed to distribute supplies and medicine," National Oceanic and Atmospheric Administration (NOAA) officials wrote.
Since vegetation plays such a large part in affecting water runoff, humidity and surface temperatures, data from Suomi and other measures of the changing plant life on our planet are now being used as part of weather prediction.
Roughly the size of a mini-van, the orbiting Suomi NPP observatory works to help predict weather and measure the effects of climate change. The satellite is run by NASA in co-operation with NOAA.
