The NASA/NOAA Suomi NPP satellite carries aboard instrumentation that carefully discerns which areas of Earth are green and which are not.
“Although 75% of the planet is a relatively unchanging ocean of blue, the remaining 25% of Earth’s surface is a dynamic green,” NOAA reports.
The Washington, D.C. area, despite some of the urban clutter, is fortunate to exist in one of the deeper pockets of greenness on our globe.
The imagery’s scientific value lies in its ability to reveal changes in land surface characteristics due to drought, floods, forest fires, and even climate change.
For example, consider this before and after fire sequence from near the Russian town of Langepas last summer. In the second (after) image, you can see the landscape turn paler and the appearance of visible scars from the fires.
The importance of monitoring Earth vegetation trends from space is apparent from the results of a climate change study released in late May. An analysis published in the journal Geophysical Research Letters found an 11 percent increase in greenness in arid areas after adjusting data for precipitation changes. This increase in foliage is largely attributable to increase in carbon dioxide concentrations, the studied found.
Here’s a video produced by NOAA which offers a 365-day tour of the evolution of vegetation on our planet – as viewed from space: