Chlorophyll is used by algae and other phytoplankton--the grass of the sea--to convert sunlight and carbon dioxide into sugars. These maps show chlorophyll concentrations in the ocean, revealing where phytoplankton are thriving.
These maps show the average amount of water vapor in a column of atmosphere by month. Water vapor is the key precursor for rain and snow and one of the most important greenhouse gases in the atmosphere.
In addition to making rain and snow, clouds can have a warming or cooling influence depending on their altitude, type, and when they form. These maps show what fraction of an area was cloudy each month.
Industrialization has brought incredible societal advances and difficult pollution problems. From space, we can see skies clearing in some regions and darkening in others. The thin blue line of our atmosphere is still quite vulnerable.
Have you ever wondered what it would be like to live in a different part of the world? What would the weather be like? What kinds of animals would you see? Which plants live there? By investigating these questions, you are learning about biomes.
These maps show the ‘metabolism” of Earth’s plants and trees. Net primary productivity is the difference between the amount of carbon dioxide absorbed during photosynthesis minus the amount released by respiration.
Whether started by humans (farming, logging, or accidents) or by nature (lightning), fires are always burning somewhere on Earth. These maps show the locations of fires burning around the world each month.
It measures about half the size of a football field and it is so small that you cannot see it on Google maps. This barren bit of rock off the coast of Canada has an unusual namesake: the Landsat 1 satellite. Hear about the discovery in the words of the woman who found it in satellite imagery.
Satellite images of Earth at night have been a curiosity for the public and a tool of fundamental research for at least 25 years. They have provided a broad, beautiful picture, showing how humans have shaped the planet and lit up the darkness.
In honor of our 20th anniversary, we offer a selection of some of the most beautiful, newsworthy, interesting, and scientifically important images from the past 20 years — one for each day of the calendar year.