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Observing NO2 in California

10.2009

Google earth image of South Coast Region of California. Google earth image of South Coast Region of California.

Aura's Ozone Monitoring Instrument (OMI) instrument focuses on the Nitrogen dioxide (NO2) in Southern California. Nitrogen dioxide is more concentrated in more densely populated urban areas. NO2 forms quickly from emissions from cars, trucks and buses, power plants, and off-road equipment. In addition to contributing to the formation of ground-level ozone, and fine particle pollution, NO2 is linked with a number of adverse effects.

NO2 columns scale
OMI Tropospheric column NO2 concentrations over CA
Tropospheric column NO2 concentrations (molecules/cm2) from the Ozone Monitoring Instrument (OMI) over the South Coast region of California from one day, August 1, 2008.
OMI Tropospheric column NO2 concentrations over CA
OMI NO2 columns averaged over summer months (Jun-Aug) for the years 2005-2008 at 0.025 degree resolution. The satellite's 16 day repeat pattern provides daily measurements which partially overlap allowing an area-weighted average to produce a higher resolution image.


Emission Reductions Show Results

Over the past several years, California has enforced aggressive air quality regulations. Results of this action can be seen in Aura's OMI imagery below. OMI shows that decreases in nitrogen dioxide (NO2) columns over the 4 years 2005-2008 approach 40%, almost the same as the weekend decrease observed in 2005.

Vehicles have a much smaller impact on local air quality than they did 20 years ago, but their emissions of heattrapping gases have continue. Mobile sources including passenger vehicles account for approximately half of California's global warming pollution.

2005 Weekdays
2005 Weekdays
2005 Weekends
2005 Weekends
2008 Weekdays
2008 Weekdays

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