RAgged Point, on the east coast of Barbados, is best known for its 19th-century lighthouse, steep cliffs, and hiking and fishing opportunities. But it has also become the center of groundbreaking scientific research that could have a significant impact on public health and how we approach climate change.
In 1966, researchers from the University of Miami established the Barbados Atmospheric Chemistry Observatory (BACO) at Ragged Point. Designed to study Saharan dust, it was the first of its kind and the reason we know as much as we do today about the phenomenon.
As many in the region know, each year—peaking between June and August—huge plumes of dust and other particles from Africa’s Sahel region travel 5,000 miles downwind toward the Americas.
Everything in the atmosphere – dust and other particles, clouds, gases, radiation from the sun – affects each other. Together, they affect the atmosphere, weather and climate, so they are best studied together. As a result, other important meteorological facilities were erected at or near Ragged Point by research and educational organizations around the world.
In 1978, the University of Bristol, the Massachusetts Institute of Technology (MIT) and other organizations established the Advanced Global Atmospheric Gas Experiment (AGAGE) as part of a network of global facilities to monitor harmful greenhouse gases.
Then, in 2010, the Hamburg-based Max Planck Institute for Meteorology established the Barbados Cloud Observatory.
And last September, the United States Naval Research Laboratory (NRL) announced the completion of the first phase of the BACO Moisture & Aerosol Gradients/Physics of Inversion Evolution (MAGPIE)-based program, whose goal is “to study the processes of the exchange of heat, moisture, African dust, and sea spray between the atmosphere and ocean over the Subtropical Atlantic Ocean.” The program will use research aircraft, satellite remote sensing courtesy of NASA, and lidar/laser and radar technology.
US-based researchers have found that serious outbreaks of Saharan dust in the Caribbean have increased by 10% since 1981 – and that the dust is contributing to drought in the Caribbean
BACO’s spacecraft already had a sun photometer, which gives the aerosol optical depth (AOD) – a measure of how much dust is in the atmosphere. The photometer is part of NASA’s Robotic Aerosol Network (Aeronet), which measures AOD worldwide.
All this has made Barbados a key location for atmospheric science.
“Barbados and Ragged Point provide a unique source of information on the intercontinental transport of materials from Africa,” explains University of Miami Professor Joseph Prospero, the research pioneer who founded BACO.
“Africa emits between 50% and 70% of total dust emissions into the global atmosphere. Most of this is carried westward across the Atlantic, where it affects the Caribbean basin and the bordering land masses—the southern United States, Central America, and northern South America. Barbados happens to lie directly on the main summer shipping path.
BArbados is also the site of the Caribbean Institute of Meteorology and Hydrology (CIMH) – an arm of CARICOM, and the main body for meteorological education and research in the region. Founded in 1967, CIMH worked with the Max Planck Institute to create the Cloud Observatory, which is co-managed by both institutions.
Dr Andrea Sealy – a meteorologist and lecturer at CIMH who studied at Howard University and other institutions in the United States before returning to Barbados in 2008 – is the leading expert on Saharan dust in the English-speaking Caribbean.
“Just before I came back to Barbados, I worked at the National Center for Atmospheric Research and worked on climate and dust modelling,” she says. “This piqued my interest in studying the dust of the Sahara, [as did] The fact that Barbados is home to the longest moving dust record… In the Caribbean, there was a gap in terms of Saharan dust work and air quality in general, [so] I decided to run with it and I don’t regret it.”
Saharan dust plumes bring important nutrients to the soil and ocean to America, but it’s a nuisance and even a hazard to people with respiratory illnesses or sensitivities. It may be causing asthma, and some research has found it increases the incidence of chronic obstructive pulmonary disease (COPD). It reduces visibility on the road and in the sky and can cause air quality in the Caribbean to be as bad as major industrialized cities. And things could get worse.
“In general, what we’ve seen in recent years is that we’ve had more intense dust episodes earlier in the year and going into the summer,” Dr Sealy said during a web presentation in April that was part of the University’s Caribbean Climate Columbia. Health Answers Course.
In June 2020, what was dubbed the “Godzilla dust event” rocked the Caribbean and parts of the US for more than a week. It was the largest such event in decades. The air quality index in Trinidad & Tobago was recorded near the top value of 500, within the limit considered dangerous.
Among the new equipment is an instrument that will measure trace metals in the atmosphere, which could help researchers understand why cases of pediatric asthma are so high in Barbados and other parts of the eastern Caribbean.
US-based researchers have found that serious outbreaks of Saharan dust in the Caribbean have increased by 10% since 1981 – and that the dust is contributing to drought in the Caribbean.
Scientists aren’t sure what caused the “Godzilla event.”
“It is possible that we will have more intense dust episodes,” Dr Sealy said Caribbean Beat. “However, due to the uncertainty in climate prediction for source regions in North Africa, there is still debate about how ‘dusty’ the future climate will be.
“So even though increased anthropogenic activity should cause more desertification and more dust lifted into the atmosphere to be transported,” she explained, “there is still uncertainty. For example, NASA published a study that predicts at least a 30% reduction in Saharan dust activity from current levels over the next 20-50 years and a continued decline beyond that.
Dr Sealy and other researchers are working to improve forecasting systems to warn people days in advance of impending dust events and their severity. This is part of her work as chair of the Pan-American node for the World Meteorological Organization’s Sand and Dust Storm Warning Assessment and Advisory System (SDS-WAS) — established in 2007 to enhance early warning efforts.
CIMH aims to be the forecasting center for the Pan-American region, and the BACO site was recently modernized with a new tower – from which will hang the all-important filters that have been used for nearly six decades to capture the dust that will are studied.
Among the new equipment is an instrument that will measure trace metals in the atmosphere, which could help researchers understand why cases of pediatric asthma are so high in Barbados and other parts of the eastern Caribbean.
Reflecting on how far the Ragged Point facility has come, Professor Prospero said: “It’s been a long struggle to convince people of the importance of this work. But it is now recognized as a critical component of understanding the direction and impact of climate change.”
