Aerosols vary a great deal from place to place and over time. Knowing their type and distribution benefits people everywhere. The Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) satellite mission will help capture a complete and accurate picture of aerosols around the globe.
The US Midwest is one of the most intense areas of agricultural production in the world and is a key player in the global economy.
Data from satellite sensors show that during the Northern Hemisphere's growing season, the US Midwest boasts more photosynthetic activity than any other spot on Earth.
Getting Better All the Time?
The 1990 Clean Air Act Amendment and other state regulations mandated significant reductions in the emission of sulfur dioxide (SO2). When in the atmosphere, SO2 gas reacts to form aerosols. Some of the most dramatic changes in SO2 have occurred in the US Midwest.
The Midwest's central location makes it a transportation crossroads and prime location for heavy industry.
Burning of fossil fuels by power plants and other industrial facilities is the largest source of SO2 in the atmosphere.
Why did conditions improve? Many power plants and other coal-burning facilities have installed flue gas desulfurization devices (“scrubbers”). These technologies can reduce emissions from a given source by 50 to 90 percent. Switching from coal with relatively high sulfur content to lower-sulfur fuel also helped reduce emissions. In some cases, coal-fired power plants were shuttered and replaced with natural gas or other cleaner energy sources such as solar or wind.
The data visualization above shows average changes in SO2 concentrations from 2005 to 2017. Contributions from natural sources (i.e., volcanoes) have been removed. [Ozone Monitoring Instrument on NASA’s Aura satellite] The data simulation below shows SO2 and sulfate aerosols from September 1 to December 31, 2006. Such simulations allow scientists to better understand how these aerosols travel through the atmosphere and impact Earth’s climate. [Goddard Earth Observing System Model Version 5, GEOS-5]
No Laughing Matter?
Unlike nitrous oxide (N2O) – a.k.a. "laughing gas" – nitrogen dioxide (NO2) in the atmosphere can create aerosols that irritate the human respiratory system. Atmospheric NO2 levels are used as a general indicator of air quality since it can quickly transform into ground-level ozone, a major respiratory pollutant in urban smog.
NO2 is a yellow-brown gas that is a common emission from cars, power plants and industrial activity.
Air pollution has decreased even though population and the number of cars on the roads have increased.
The positive shift is the result of regulations, technology improvements and economic changes, according to scientists.
These data highlight the impact of technology to reduce NO2 and SO2 emissions from coal-fired power plants in the Ohio River Valley and other parts of the US.
While air quality is generally improving in the US, power plant emissions of the greenhouse gas carbon dioxide remain an issue. Looking back at the past – and ahead to the future – reveal the importance of keeping a close eye on the potential impacts of climate change in the Midwest.
On November 11, 1933, a very strong dust storm stripped topsoil from desiccated South Dakota farmlands in just one of a series of severe dust storms that year. The following May, a two-day dust storm removed massive amounts of Great Plains topsoil. Dust clouds blew all the way to Chicago, where they deposited 12 million pounds of particles. Two days later, the same storm reached cities to the east, such as Cleveland, Buffalo, Boston, New York City, and Washington, DC.
At the end of this century, droughts in the US could be drier and longer compared to conditions seen in the last 1,000 years. This forecast is based on projections from several climate models. Researchers found the risk of severe droughts would increase if human-produced greenhouse gas emissions continue to increase. Unlike the 1930s Dust Bowl, which lasted less than a decade, future droughts may last 30 to 35 years.
A team of researchers led by scientists at NASA’s Goddard Institute for Space Studies analyzed model results from a moderate climate scenario where greenhouse gas emissions stop increasing by the year 2050. The video below shows soil moisture changes with browns indicating drier regions, while blues indicating wetter regions.
Wanna Get Away?
The Bahamas is the site of Christopher Columbus's first landfall in the New World in 1492. Today, it is a popular vacation destination known for its scenic beauty and year-round tropical weather.
Located east and south of Florida, the Bahamas consists of more than 700 islands, cays, and islets in the Atlantic Ocean.
Only 30 of its largest islands are inhabited, helping maintain its generally good overall air quality.
In the data model visualization below, green represents organic carbon, black carbon, and sulfate aerosols. Organic and black carbon come from burning biomass or fossil fuels. Sources include fires, power plants, vehicles, and other combustion engines that run on fossil fuel. Sulfate particles come mostly from burning fossil fuels, but also from volcanoes.
Scheduled to launch in 2024, PACE will extend and improve NASA's over 20-year record of observing ocean life, aerosols, and clouds.
PACE observations of aerosols over this region will help us keep track of smog and other aerosols affecting our health and climate.
More wavelengths. Unprecedented resolution.
Links and Other Information
- Satellite Shows High Productivity From U.S. Corn Belt [NASA Scientific Visualization Studio]
- Water as Acid Rain [US Geological Survey]
- Sulfur Dioxide Down Over the United States [NASA Earth Observatory]
- Sulfur Dioxide 2018 Update [NASA Scientific Visualization Studio]
- Nitrogen Dioxide (NO2) Pollution - Basic Information [Environmental Protection Agency]
- Nitrogen Dioxide Reduction Across the Ohio River Valley [NASA Scientific Visualization Studio]
- A Decade of Change for Nitrogen Dioxide [NASA Scientific Visualization Studio]
- Dust Bowl [Wikipedia]
- Buried Machinery in a Barn Lot; Dallas, South Dakota, May 1936 [Wikipedia]
- Megadrought [NASA Scientific Visualization Studio]
- Gateway to Astronaut Photography of Earth [NASA Johnson Space Center]
- The Bahamas [NASA Earth Observatory]
- Satellite Tracks Saharan Dust To Amazon In 3-D [NASA Scientific Visualization Studio]
- Aerosol Optical Thickness Updating Forecast [NASA Scientific Visualization Studio]
- Sources of Aerosols [NASA Scientific Visualization Studio]
- Other images used under 123rf License Agreement [ID 93302171, 47210792, 13954012, 52704263, 11007139, 20487622, 16698260, 93812475, 14842435, 114751919, 30263621, 67335951, 99864921, 120126326]