Jul 6, 2020
Dan Cziczo, Professor of Atmospheric Science and head of the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University. His group specializes in the study of aerosol particles in the atmosphere. Aerosol particles act as the seeds on which water, clouds, and ice crystals form within the atmosphere. The presence of these particles in the atmosphere scatter sunlight and cause hazy atmospheric conditions. Aerosols also influence the outgoing radiation from Earth to space, thereby making them a complex player in the energy balance of the Earth. One of the instruments used by Cziczo is a single particle mass spectrometer. His group has deployed this instrument on various NASA research aircraft and several years ago they were able to collect data from a base in Florida that was scheduled to fly through a Saharan dust storm. From this mission, Cziczo’s group was able to collect and analyze the chemical fingerprints of dust particles within that storm. Cziczo explains that Saharan dust storms are very common and have happened frequently for thousands of years during the summer. They are part of the trade winds and occur when material gets picked up off the arid regions of the Sahara and moves from east to west, where it ends up over either the Caribbean or Amazon. Occasionally, these storms will make their way over the continental United States. The most recent dust storm (Summer 2020) was a larger than normal storm and one that Cziczo classifies as a 50 year event. Small bits of this recent storm made it as far north as Minnesota and Canada. Cziczo mentions that aerosol particles can circle the globe several times before finally settling and he provides links (below) for listeners to be able to look up satellite imagery of these particles. While air quality (hazy conditions, pollution, pathogen transport) can be negatively impacted by the particles transported during dust storm events, they can also have a positive impact such as providing fertilization for the Caribbean islands, coral reefs, and even the Amazon rainforest. Cziczo mentions that ultimately, these dust storms
are an important part of our global system.
Links:
NASA MODIS / Dust Storms https://earthdata.nasa.gov/earth-observation-data/near-real-time/hazards-and-disasters/dust-storms
NOAA https://www.nesdis.noaa.gov/content/it%E2%80%99s-dusty-world-noaa-satellites-help-us-keep-track-it
NASA Earth Observatory on this dust storm : https://earthobservatory.nasa.gov/images/146913/a-dust-plume-to-remember