This is a new kind of satellite image of the Earth, showing nothing but vegetation. It allows us to track just how fecund the planet is — and to spot trouble regions where crop growth may soon be hindered by drought. Soon, images like these could become a crucial part of food security.
This complete picture of the planet's plant life is product of a year's worth of images collected from Earth's orbit between April 2012 and April 2013. Up top is a close-up of the Western Hemisphere. Here's a view of our planet from the other side:
You can see the Sahara Desert easily here — it's the big area without green on the northern half of the African continent.
These images are part of a newly released series entitled "Herbal Earth," the latest in a recent string of magnificent high-resolution images and animations produced in a joint effort by NASA and NOAA, including at updated "Blue Marble" photograph and a brand new "Black Marble" snapshot – the latter being an unprecedented view of our planet at night.
These new views of Earth have all been made possible by Suomi NPP, a next-generation Earth-observing satellite launched toward the end of 2011 by NASA, in partnership with NOAA. The satellite collects the images with its Visible-Infrared Imager/Radiometer Suite (VIIRS) instrument, which records large swaths of the planet's surface every time it orbits. Collect these images over time, and it's possible to produce a month-to-month animation of vegetation distribution across the Earth, like the one seen above.
The Agencies use these data to monitor vegetation conditions worldwide, and produce what's called the Normalized Difference Vegetation Index (NDVI). NDVI can be used to assess the photosynthetic potential of vegetation across the globe; monitor the impact of varying climate conditions, like drought; or even study the life-imparting qualities of a river system like the Nile, pictured below.