Saharan Dust Haze in Saint Barthelemy
A 3,000-mile journey: when desert dust crosses the Atlantic to tint Caribbean skies
Current Visibility
Real-time atmospheric conditions
No ongoing episode
Saharan dust haze: a spectacular yet misunderstood natural phenomenon
Although often perceived as a nuisance, Saharan dust haze is a fascinating natural phenomenon that plays a crucial ecological role in the Caribbean balance.
"Saharan dust makes Saint-Barth unlivable during summer and ruins vacations"
Episodes last 2 to 7 days, the island remains fully enjoyable and offers spectacular sunsets
Why does this phenomenon exist?
Each year, between 40 and 100 million tons of Saharan dust are transported across the Atlantic by trade winds. This cloud of fine particles travels over 3,000 miles in 5 to 7 days, creating a natural aerial bridge between Africa and the Americas.
Far from being simple pollution, this mineral-rich dust (iron, phosphorus, calcium) fertilizes the Amazon rainforest, nourishes oceanic phytoplankton, and even helps inhibit hurricane development by drying out the tropical atmosphere.
When does Saharan dust arrive in Saint-Barth?
Understanding the annual calendar of episodes to better plan your stay or anticipate impacts
June - August
Most intense peaks with 2 to 4 episodes per month. Trade winds are at their maximum.
Apr, May & Sep
Occasional short-duration episodes. Moderate intensity.
Oct - March
Very rare. The peak tourist season is completely unaffected.
How does Saharan dust form? Scientific explanations
Formation in the Sahara
Sandstorms in the Sahara lift massive amounts of fine dust up to 15,000 feet altitude. These particles, composed of quartz, clay, and minerals, form what is called the "Saharan Air Layer" (SAL).
This layer of hot, dry air, lighter than the surrounding humid tropical air, moves at altitude like an atmospheric conveyor belt.
Atlantic crossing
Pushed by easterly trade winds, these particles travel 3,000 to 4,500 miles at speeds of 12 to 25 mph. The journey takes between 5 and 7 days, during which the heaviest particles gradually fall into the ocean.
Only the finest particles (less than 10 microns) reach the Caribbean, creating this characteristic haze that can persist 2 to 7 days depending on the episode's intensity.
Beneficial ecological role
- •Amazon fertilization: 27 million tons of dust fertilize the tropical rainforest each year
- •Ocean nutrition: The minerals nourish phytoplankton, the base of the marine food chain
- •Hurricane regulation: The dry air inhibits hurricane formation by reducing atmospheric humidity
What are the impacts of Saharan dust in Saint-Barth?
- 50 to 80% reduction
- Hazy sky, milky color
- Blurred horizon
- PM10 and PM2.5 fine particles
- Degraded air quality index
- Possible respiratory irritation
- Spectacular sunsets (red/orange)
- Unique diffused light
- Atmospheric photography
How to manage a Saharan dust episode?
Asthmatics, elderly, children, cardiac patients
- •Limit intense outdoor activities
- •Wear an FFP2 mask if you are sensitive
- •Stay hydrated regularly
- •Consult a doctor if you experience respiratory discomfort
Homeowners, renters, villa managers
- •Close windows during peaks
- •Clean your vehicle after the episode
- •Rinse terraces and outdoor furniture
- •Increase pool filtration
Tourists, residents, photographers
- •Prefer water activities (swimming)
- •Wear sunglasses
- •Explore air-conditioned shops and restaurants
- •Enjoy the exceptional sunsets
Frequently Asked Questions
For the majority of healthy people, Saharan dust is only a temporary inconvenience. People with asthma, allergies, or respiratory problems should limit intense outdoor activities and consult their doctor if necessary.
A Saharan dust episode typically lasts between 2 and 7 days. The most intense episodes (June-July) can persist a week, while spring episodes are shorter (2-3 days).
Yes! Water activities (swimming, diving, paddleboarding) remain fully enjoyable because the haze only affects atmospheric visibility, not water quality. It's even recommended to escape particles suspended in the air.
Regularly check our homepage which displays the current haze status. Local weather forecasts and satellite images allow anticipating episodes 3 to 5 days in advance.
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