Earth  ID: 4431

Ozone Transport in the Tropical Western Pacific

NASA-funded scientists have traced the origins of mysterious pockets of high ozone concentrations and low water vapor in the air above the western Pacific Ocean near Guam to fires burning in Southeast Asia and in Africa, half a world away.

These pockets of ozone—a powerful greenhouse gas—are three times more concentrated than surrounding air and are found at around 30,000 feet in the lower part of Earth’s atmosphere known as the troposphere, within the cruising altitude of most commercial airliners. As a greenhouse gas, ozone in the troposphere is an important contributor to global warming, but because it varies widely in where it occurs and how long it stays aloft, its true impact on climate change is hard to determine.

Researchers studying the air over Guam during the winter of 2014 during a pair of airborne field campaigns captured a comprehensive picture of the chemicals traveling with the ozone—chemicals such as hydrogen cyanide and acetonitrile, which originate in fires. Using a data-driven computer model, they then traced the ozone-laden air pockets back 10 to 15 days in most cases—right back to fires in either Southeast Asia, about 2,000 miles away, or tropical Africa, over 8,000 miles away.

The animation begins by showing a single NCAR Gulfstream V aircraft flight from the CONTRAST campaign that was outfitted to measure various trace gases. From the measurements taken on this flight, the backflow trajectories are modelled using the NOAA HYSPLIT model, stepping back in time for the previous 10 days or until the trajectories encountered convection. The trajectories are coloured by observed aircraft ozone level where blue values represent low concentrations of ozone and red represents high values. The ozone value is invariant along each trajectory. The active fire locations detected during the prior 48 hours are shown as yellow/gold points. Areas depicting highly convective regions are shown in white.


Visualization Credits

Cindy Starr (GST): Lead Visualizer
Greg Shirah (NASA/GSFC): Visualizer
Daniel C. Anderson (University of Maryland): Scientist
Laurence Schuler (ADNET Systems, Inc.): Technical Support
Ian Jones (ADNET Systems, Inc.): Technical Support
Joycelyn Thomson Jones (NASA/GSFC): Project Support
Leann Johnson (GST): Project Support
Eric Sokolowsky (GST): Project Support
Ellen T. Gray (ADNET Systems, Inc.): Producer
Sophia Roberts (USRA): Producer
Kayvon Sharghi (USRA): Producer
Please give credit for this item to:
NASA's Scientific Visualization Studio

The Blue Marble data is courtesy of Reto Stockli (NASA/GSFC).

Fire location data courtesy of MODIS Rapid Response Project (NASA/GSFC and University of Maryland -

Science Paper:
Anderson, D.C. et al. (2016) A pervasive role for biomass burning in tropical high ozone/low water structures, Nature Communications, 7, doi:10.1038/ncomms10267.

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Data Used:
Aircraft/Fast 03/CONvective TRansport of Active Species in the Tropics: flight 13 02/19/2014
TRMM and Multiple Geostationary Satellites/Convection Product (Combination of Precipitation Observations) 02/10/2014 - 02/19/2014
Terra and Aqua/MODIS/Fire Location 02/10/2014 - 02/19/2014
Back Trajectories (Calculated with the NOAA HYSPLIT Model) 02/10/2014 - 02/19/2014
Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site.

SVS >> Transport
GCMD >> Earth Science >> Atmosphere >> Atmospheric Chemistry/Oxygen Compounds >> Ozone
SVS >> Hyperwall
NASA Science >> Earth

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version