NASA logo

Aura Science

First global tropospheric maps show streams of tropospheric ozone crossing the oceans


OMI & MLS can estimate the tropospheric ozone residual by subtracting the MLS stratospheric ozone from OMI column ozone. High residual regions correspond to pollution sources and transport.

figure 3 : diagram OMI & MLS measure ozone

Tropospheric ozone residual (TOR) is computed by subtracting the stratospheric column ozone from the total column ozone. The stratospheric column ozone is computed using the MLS limb measurements of ozone. The total column O3 is measured by OMI, and the TOR is the difference between them.

figure 4 : October 2004 & July 2005 Tropospheric Ozone measurements

The monthly mean maps of the TOR show pollution streaming from the U.S., Europe and China to the west in summer and pollution from biomass burning in the equatorial zone.

+ Aura's Top 10 Feature