By Nigel Jaffe
In honor of the 50th anniversary of the landmark Apollo 11 launch—the spaceflight that first landed humans on the Moon—this coming Saturday, today’s Map of the Week looks at how NASA data can be harnessed to create incredibly detailed, vibrant depictions of how the earth changes between seasons.
This map was created by Eleanor Lutz, a Ph.D student in the department of Biology at the University of Washington. It shows the way the surface of the Earth changes perceptibly each month with the warming and cooling of the seasons; in winter, ice dominates much of the northern portion of the globe, before receding in the summer as the eastern United States and sub-Saharan Africa sport a vivid shade of green. Other distinct changes are visible in Spain and eastern Brazil, where the landscape is green in the winter and light brown in the summer.
In the top left and right corners of the map, aerial views from each pole show how ice caps grow and shrink each season. Meanwhile, in the bottom left corner is a map (dark blue-green) that shows seasonal changes in the average amount of clouds in the sky, and in the opposite corner is a similar map (red) showing the amount of sunlight that reaches the Earth.
Lutz’s animations, which are comprised of 12 frames—one for each month of the year—combine data from several sources to show patterns of cloud cover, sunlight exposure, and Arctic ice patterns. To create those images, Lutz relied on data sets from 2004 published online by NASA on their Earth Observations website, which includes data focusing on a variety of areas of interest. Those data sets were illustrated on a smaller scale in several other animations Lutz created through the same technique:
These maps depict a selection of data sets from the NASA Earth Observations collection: fire incidence (1), vegetation (2), solar insolation/amount of sunlight (3), cloud fraction/coverage (4), North Pole ice sheet coverage (5), and “Blue Marble” satellite images (6). Lutz combined the ice sheet data (5) and the satellite images (6), along with U.S. Geological Survey data on tectonic plate locations, to create an original (7), which you may recognize as the map shown on a larger scale above. That final version was created with the help of Natural Earth, a public domain map data set; the NASA data was layered over their template for the coastlines and their labels for cities, ice sheets, lakes, etc.
More of Lutz’s animations and scientific visualizations, including topographical maps of Mercury and Mars, can be found on her blog.