CALIPSO observes Saharan dust crossing the Atlantic Ocean
Visualizer: Kel Elkins
For the first time, a NASA satellite has quantified in three dimensions how much dust makes the trans-Atlantic journey from the Sahara Desert the Amazon rainforest. Among this dust is phosphorus, an essential nutrient that acts like a fertilizer, which the Amazon depends on in order to flourish.
The new dust transport estimates were derived from data collected by a lidar instrument on NASA's Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation, or CALIPSO, satellite from 2007 though 2013.
We work with many Earth science datasets in different geographic projections that must be accurately positioned on a globe. We developed an IDL routine that automatically extracts the coordinate and projection information from geotif images. For each image, this routine writes out a Renderman Shading Language #include file passing the correct parameters to a projection routine that positions the related texture tile. The projection routine is a C++ Renderman plugin that computes the projection calculations in double precision.
We wanted to see if we could visualize the so-called ocean garbage patches. We start with data from floating, scientific buoys that NOAA has been distributing in the oceans for the last 35-year represented here as white dots. Let's speed up time to see where the buoys go... Since new buoys are continually released, it's hard to tell where older buoys move to. Let's clear the map and add the starting locations of all the buoys... Interesting patterns appear all over the place. Lines of buoys are due to ships and planes that released buoys periodically. If we let all of the buoys go at the same time, we can observe buoy migration patterns. The number of buoys decreases because some buoys don't last as long as others. The buoys migrate to 5 known gyres also called ocean garbage patches.
Events called stratospheric ozone intrusions occur most often in spring and early summer, and can raise ground-level ozone concentrations in some areas to potentially unhealthy levels.
This visualization shows one such event that occurred On April 6, 2012. On that day, a fast-moving area of low pressure moved northeast across states in the Western U.S., clipping western and northern Colorado. Ozone-rich stratospheric air descended, folding into tropospheric air near the ground. Winds took hold of the air mass and pushed it in all directions, bringing stratospheric ozone to the ground in Colorado and along the Northern Front Range.