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Smog in Shanghai, China

NASA's Fleet of Earth Observing Satellites: Monitoring Our Planet's Health


NASA has a fleet of Earth-observing satellites whose instruments observe our planet's oceans, biosphere, and atmosphere. Several of these satellites have instruments that observe air pollutants around the world. The data collected are being used by air quality managers and researchers studying the impact of air pollution on human health and agriculture.

Air Pollutants Observed from Space


Nitrogen Dioxide (NO2): NO2 is unhealthy to breathe and is primarily generated during fossil fuel combustion, so thermal power plants and automobiles are the dominant sources.

Ozone (O3) & Precursors: At Earth's surface, O3 is unhealthy to breathe and also negatively impacts plants, reducing crop yields.

Particulate Matter (PM) & Precursors: PM are tiny particles (e.g., smoke and dust) that cause numerous health issues when breathed in.

Impacts of Air Pollution: How Satellite Data Can Help


Human Health: Exposure to outdoor air pollution is responsible for an estimated 4 million premature deaths annually with about another 3-4 million resulting from exposure to indoor air pollution; that is, air pollution is responsible for about 1 in 9 deaths worldwide (WHO, 2018;  Cohen et al., 2017). The State of the Global Air webtool allows you to view historical trends of air pollutants for your city with the concomitant impacts on human health.

Agriculture: The economic impact of crop yield loss due to pollution is significant all over the world. Air pollution causes global crop yield losses for wheat, corn, and soybeans that are estimated to range from 11-18 billion annually, with the greatest economic loss estimated to occur in the United States ($3.1 billion).


Global ABS Visualization for 2014Global ABS Visualization for 2005 Global ABS Visualization for 2014

The slider above shows satellite data of nitrogen dioxide (NO2) from the Aura Ozone Monitoring Instrument (OMI) data for two years, 2005 (left) and 2016 (right). The data indicate that levels of this pollutant changed significantly over the last decade in many places around the world.  Slide the bar from back and forth to see these changes.  More information on NO2 trends for each region and more than 300 world cities can be found under the Nitrogen Dioxide tab.


COVID-19 Impacts on Global Air Pollution

Efforts to contain the spread of COVID-19 led to unprecedented changes in air pollution levels around the world, which NASA satellites observed. Professionals from a number of disciplines have used these data to assess the impact of the pandemic. As an example, one pollutant, nitrogen dioxide (NO2), is unhealthy to breathe and also a tracer of human activities as it is emitted during fossil fuel combustion. Here are a few examples of how NO2 data were used:

  • Air quality managers were interested in NO2 data to assess the impact of lockdowns on air pollution levels.
  • Health professionals used NO2 data to gauge the effectiveness (e.g., reduction in emissions from traffic and industry) of lockdown efforts to contain or slow the pandemic in a given area.
  • Climate researchers used NO2 data as a proxy for co-emitted CO2 emissions and, thus, inferred the changes in climate gases from cities and power plants.
  • Given that most world economies are driven by fossil fuels, economists used  NO2 data, a non-traditional source of data for this community, to assess the impact of the pandemic on economic activity around the world, including in countries without reliable economic data.
  • The global intelligence community likely used NO2 data for assessing the impact of the pandemic on world countries, including with world governments that purposely misrepresent or withhold the true extent of the pandemic’s impact.

Learn more about impacts from COVID-19

2015-2019 Average NO2 for the Northeast US 2020 NO2 Map for the Northeast US

The slider above shows satellite data of NO2 from the Aura Ozone Monitoring Instrument (OMI) over the Northeast United States. The image on the left shows the mean of the period from 2015 through 2019, while the image on the right shows the mean for 2020, during the pandemic lockdowns. Though variations in weather from year to year cause variations in the monthly means for individual years, March 2020 shows the lowest values as compared to any of the monthly values for March during the OMI data record, which spans 2005 to present. In fact, the data indicate that the NO2 levels in March 2020 are about 30% lower on average across the region of the I-95 corridor from Washington, DC to Boston than when compared to the mean of 2015 to 2019.



NASA Health & Air Quality Applied Sciences Team (HAQAST) - HAQAST team members will work with you on your air quality issues using a combination of satellite data, surface data, and models.



NASA Applied Remote SEnsing Training (ARSET) - The ARSET program offers free webinars and in-person trainings on the use of NASA satellite data for Health and Air Quality Applications.

NASA Food Security Initiative

The NASA Goddard Space Flight Center's Food Security Initiative promotes the use of Earth observations and Earth science data, models, and knowledge provide essential information and tools to support global food security. (Photo by Ishay Botbol from Pexels)

NASA AQ Forecast

The NASA Global Modeling and Assimilation Office (GMAO) develops and maintains the GEOS system of models, which has a suite of capabilities including simulating weather, climate, chemistry-climate interactions, and now air pollution. Visualize the forecast output with FLUID.

NASA Applied Sciences

The NASA Applied Sciences Health & Air Quality (AQ) Program promotes innovation in public and private sector organizations to apply NASA satellite data, model products, and scientific findings in air quality management and policy activities that benefit human health and safety.

Access nitrogen dioxide data and trends for cities around the world. The data are from the NASA Aura satellite, launched in 2004.