Desert dust forecast to reduce health risks

Astronaut Doug Hurley watches the 2020 desert dust plume from the space station. He took this photo and posted it on Twitter. From Hurley’s tweet: “Today we flew over this desert dust plume in the West Mid-Atlantic Ocean. It’s amazing how wide the area it covers.” Credit: NASA/Doug Hurley

In the summer of 2020, the winds carried nearly 24 tons of dust across the Atlantic Ocean from the Sahara desert in Africa to North and South America, hitting the Caribbean islands with particular force.

This was one of the largest desert dust storms on record and it came in the midst of a global pandemic. An African dust early warning system was developed with funding from NASA and a few days before the event it was installed in Puerto Rico. Using this tool, for the first time, citizens across the island received advance notice that a sandstorm was coming.

“We were watching two different models and satellite images from NASA,” said Pablo Mendes Lazaro, associate professor on the University of Puerto Rico San Juan’s Medical Sciences campus, who led the development of the alert system.

“As soon as we saw the dust storm, we started spreading the news,” he said. “We contacted the competent government agencies and cooperating doctors.”

Desert dust clouds make this journey every year, fertilizing the soil with phosphorous and other nutrients. The right amount of dust feeds Caribbean corals, but too much dust can lead to excessive algae growth. It can also irritate people’s eyes, ears, nose, and throat with fine particles of silica and other minerals that can infiltrate lung tissue and exacerbate allergies and reduce vision.

“During the summer of 2020, as in many other places, we were also fighting COVID-19, and COVID-19 is a respiratory virus,” said Mendez-Lazzaro. “We were very concerned about how dust could exacerbate symptoms.”

Early warning and better preparation

The Desert Dust Alert System involves monitoring satellite data, collecting samples and alerting government agencies and the public, giving people time to prepare.

The 2020 dust storm, nicknamed Godzilla, was so large that astronauts on the International Space Station could see it.

Mendez Lazaro and his team use a variety of NASA instruments and sensors to track aerosols — which can be liquids, gases, bacteria, viruses, and volcanic ash as well as dust — primarily with NASA’s Visible Infrared Imaging Radiometer array (NASA’s VIIRS at the National Alliance’s Sumi Satellite). For Polar Satellites (NPP).

The VIIRS instrument allows researchers to determine the visual depth of aerosols, which is an indicator of the amount of aerosols in the atmosphere.

This animation shows the aerosol trajectory in the desert dust plume from June 15-25, 2020, which was generated from the Suomi NPP OMPS Aerosol Index. Researchers at the University of Puerto Rico in San Juan, funded by NASA, are using satellite data to track dust and other aerosols traveling across the Atlantic from the Sahara Desert. They alert local and federal governments and the public before air quality deteriorates. Credit: NASA/NOAA/Colin Seftor

“It could be a bunch of different things, so the satellite information isn’t enough to know what kind of aerosol is there,” Mendez-Lazaro said. “But because of the dust cloud’s trajectory, you know where it came from, and from ground sampling, you know where it was born.”

Additional information about the path and origin allows scientists to confirm that the cloud is in fact dust from the desert, helping them to predict its effects.

Several days before the 2020 storm, Mendes Lazaro’s team held a live event on their Facebook page with one of Puerto Rico’s top meteorologists, Ada Monzón, which reached nearly 300,000 viewers. Mendez Lazaro also spoke about the hazardous weather conditions in another Facebook Live broadcast from the San Juan National Weather Service.

Monzon and other meteorologists have included information in their forecasts so that the public and especially vulnerable groups — including the elderly, children under five, pregnant women, and people with asthma or other respiratory or skin problems — can take precautions and avoid exposure. the outside.

Mendez Lazaro and his team also provided visualizations through a tool that they planned to make public. Based on the warnings, the Puerto Rico Health Bureau issued recommendations for public health. The advance warning from satellite data also allowed the team to take ground samples for the system to prepare for rapid analysis and characterization of the dust, which caused two days of unhealthy weather conditions in Puerto Rico.

A better understanding of dust could help clinicians treat patients with its health effects, especially if the dust carries pathogens, and allow researchers to retrospectively analyze early satellite data to make possible improvements in future predictions.

Earth notes on Earth

Mendez-Lazzaro and his team developed the alert system with funding from a three-year NASA Applied Science grant awarded in 2019. All proposals have been peer-reviewed.

By the time the storm hit in 2020, an early version of Puerto Rico’s warning system had been implemented. Mendez Lazaro and colleagues also worked to expand it to the US Virgin Islands.

The team is currently establishing a sustainable partnership with the National Oceanic and Atmospheric Administration’s (NOAA) Caribbean Coastal Ocean Observing System (CARICOOS), to keep the system operating after funding from NASA ends.

Mendez-Lazzaro received additional funding from NASA in 2020 to investigate how dust plumes from the desert and other environmental factors affect the spread and severity of COVID-19.

“We were concerned that people already fighting the virus could get worse and their symptoms could be more severe because African dust is another aggravating factor affecting the pulmonary system,” Mendez-Lazzaro said. His team continues to analyze the data and plans to report preliminary findings on this topic in the near future.

Mendez Lazaro’s work is a perfect example of your program’s mission, said John Haynes, who directs Air Quality and Health Applications in the Applied Science Program in the Division of Earth Sciences at NASA Headquarters in Washington.

“Our mission is to discover and demonstrate innovative and practical uses for Earth observation,” said Hines, who served as a technical officer on the NASA side of both projects.

Terabytes of Earth data are downloaded daily from NASA’s constellation of Earth observation satellites. This information is used to answer basic scientific questions about how Earth’s systems are changing. NASA’s Applied Science Program then aims to put this information into the hands of the people who make predictions and policy decisions, so that those decisions can be made faster or better.

“Pablo and his team benefit not only from VIIRS optical depth data, but also from ground observations,” Haynes said. “They collect this information and present it to other agencies in useful formats so that they can make better decisions when these dust storms are expected.”

By Rebecca Carroll
NASA Publications Spinoff 2022

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