Twenty years is but a blink of the eye in the lifespan of our planet, but as ever-improving satellite imagery continues to show, it is more than enough time to observe profound changes in its weather and surface features. NASA has just introduced a new tool where 20 years worth of satellite photos can be browsed one by one, with the ability to watch on as major events like forest fires and hurricanes play out.
This new interactivity comes courtesy of the latest upgrade to NASA's Worldview tool, which has offered access to daily imagery from the Terra satellite since 2012. That satellite launched in 1999, and Worldview now combines this with images from the Aqua satellite, launched in 2002, to form the longest continuous daily global satellite observation of Earth ever recorded.
The updated Worldview tool allows users to add layers to the global map. For example, by navigating to and selecting the option for "sea ice," patches of pink will then represent its concentration around the world. You can then flick through the days, months or years to see how it changes over time. Events like major fires, volcanic eruptions, along with the evolution of mangrove forests, cloud pressure, snow cover and sea surface temperatures are just few layer options.
Worldview is a bit of fun to play around with for folks with an interest in the environment and how it is changing, but for scientists studying such things it can serve as as invaluable professional tool.
"In the '80s and '90s, if you wanted to look at, say, clouds off the coast of California, you had to figure out the time of year when it was best to look at these clouds, then place a data request for a specific window of days when you thought the satellite overflew the area," says Santiago Gassó, an associate research scientist with NASA's Goddard Earth Sciences Technology And Research program.
"You would get a physical tape with these images and have to put this into the processing system," Gassó continues. "Only then would you know if the image was usable. This process used to take from days to weeks. Now, you can look at images for days, weeks and even years in a matter of minutes in Worldview, immediately find the images you need, and download them for use. It's fantastic!"
The video below offers a demonstration of Worldview's new functionality, and you can jump on to have a look at it yourself here.
Source: NASA
