What's New with Earth Today

As cities and countries locked down during COVID-19, some changes were visible from space. NASA, ESA and JAXA have partnered to create a dashboard making those data available.Read more: https://www.nasa.gov/press-release/nasa-partner-space-agencies-amass-global-view-of-covid-19-impacts || The collective power of space-based Earth observations from NASA, ESA (the European Space Agency), and the Japan Aerospace Exploration Agency (JAXA) to see global changes around the world has been harnessed to produce the COVID-19 Earth Observation Dashboard, released on June 25. In this video, leaders from each agency – Thomas Zurbuchen (NASA), Josef Aschbacher (ESA), and Koji Terada (JAXA) – discuss their unprecedented collaboration.Complete transcript available. ||

NASA, ESA (European Space Agency) and JAXA (Japan Aerospace Exploration Agency) have created a dashboard of satellite data showing impacts on the environment and socioeconomic activity caused by the global response to the coronavirus (COVID-19) pandemic.The dashboard will be released on Thursday, June 25 during a tri-agency media briefing. The briefing speakers are:•Josef Aschbacher, director of ESA Earth Observation Programmes•Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate•Koji Terada, vice president and director general for the Space Technology Directorate at JAXA•Shin-ichi Sobue, project manager for JAXA’s ALOS-2 mission•Ken Jucks, program scientist for NASA’s OCO-2 and Aura missions•Anca Anghelea, open data scientist, ESA Earth observation programmes ||

On June 1, the World Health Organization noted that Central and South American countries have become “the intense zones” for COVID-19 transmission. The Ozone Monitoring Instrument (OMI) on board NASA’s Aura satellite provides data that indicate that restrictions on human activity have led to about a 36% decrease in NO2 levels in Rio de Janeiro, Brazil, relative to previous years. Other large cities in South America show similar decreases in NO2: 36% in Santiago, Chile; 35% in São Paolo, Brazil; and 40% in Buenos Aires, Argentina. One notable exception is in Lima, Peru, showing a 69% decrease. The large decrease may partly be associated with natural variations in weather that can, for instance, disperse air pollution more quickly. Additional analysis is required to determine the amount of the decrease of NO2 in Lima that is associated with a decrease in human activity. A notable increase in NO2 occurred in northern South America, which is likely associated with increased agricultural burning in 2020 relative to previous years. ||

Over the past several weeks, the United States has seen significant reductions in air pollution over its major metropolitan areas. Similar reductions in air pollution have been observed in other regions of the world. || Tropospheric NO2 Column, Animated GIF || These recent improvements in air quality have come at a high cost, as communities grapple with widespread lockdowns and shelter-in-place orders as a result of the spread of COVID-19. One air pollutant, nitrogen dioxide (NO2), is primarily emitted from burning fossil fuels (diesel, gasoline, coal), coming out of our tailpipes when driving cars and smokestacks when generating electricity. Therefore, changes in NO2 levels can be used as an indicator of changes in human activity. However, care must be taken when processing and interpreting satellite NO2 data as the quantity observed by the satellite is not exactly the same as the NO2 abundance at ground level. NO2 levels are influenced by dynamical and chemical processes in the atmosphere. For instance, atmospheric NO2 levels can vary day-to-day due to changes in the weather, which influences both the lifetime of NO2 molecules as well as the dispersal of the molecules by the wind. It is also important to note that satellites that observe NO2 cannot see through clouds, so all data shown is for days with low amounts of cloudiness. If processed and interpreted carefully, NO2 levels observed from space serve as an effective proxy for NO2 levels at Earth's surface.NASA's air quality group is also monitoring other air pollutants, such as sulfur dioxide (SO2). Major anthropogenic activities that emit SO2 include electricity generation, oil and gas extraction, and metal smelting. SO2 is emitted during electricity generation if the coal burned has sulfur impurities that are not removed (or not “scrubbed”) from the plant’s exhaust stacks.For more information on what pollutants NASA satellites observe, visit the NASA Air Quality website. ||

TROPOMI Nitrogen Dioxide animation. || Preventative measures adopted to reduce the rate of spread of COVID-19 in the U.S. prompted an overall slowdown in economic activity and fewer vehicles on the roadways in the spring of 2020. To examine changes in air quality in California, NASA constructed weekly averaged nitrogen dioxide (NO2) maps for March and April 2020 at 0.05° grid spacing from high-quality, cloud-free retrievals provided by Tropospheric Monitoring Instrument (TROPOMI) level 2 data.During first weekday period (March 2-6, pre-shutdown) when COVID-19 measures were yet to be implemented, the largest tropospheric NO2 concentrations were observed in Los Angeles and bordering counties with a less prominent peak in NO2 around San Francisco. The TROPOMI scans also resolved areas of enhanced NO2 along the heavily trafficked corridor of State Route 99 (SR-99) in the Central Valley. As initial, soft COVID-19 measures were adopted by businesses in California during the second weekday period, March 9-13, TROPOMI observed strong reductions in tropospheric column NO2 around the large cities of Los Angeles and San Francisco along with noticeable decreases along SR-99. When California announced statewide “shelter-in-place” orders during the third weekday period, March 16-20, further decreases in NO2 were apparent throughout all populated areas in the state and along SR-99. Further weekly areages showed variable decreases in NO2 as decreased economic activity continued. Overall, these observed reductions in TROPOMI NO2 throughout the spring season are the result of decreased emissions on top of the seasonal changes in meteorological conditions. ||

Tropospheric NO2 Column, March 15-April 15 2015-2019 average vs. 2020, USA regions || These images show the impact the spread of the novel coronavirus (COVID-19) has had on reducing air pollution in the United States as widespread lockdowns and shelter-in-place orders have been put in place. The images show a reduction in the levels of nitrogen dioxide (NO2)—a noxious gas emitted by motor vehicles, power plants, and industrial facilities—as measured by the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite in March 2020. The “without stay-at-home orders” images show average monthly NO2 concentrations during March and April from 2015 through 2019, while the “during stay-at-home orders” images show average monthly concentrations in March and April 2020. These improvements in air quality have come at a high cost, as communities grapple with the impacts of COVID-19. The data indicate that the NO2 levels in March and April 2020 are much lower on average across the United States when compared to the mean of 2015 to 2019. ||