Saharan Dust returned across Trinidad, Tobago, and the Lesser Antilles on Saturday morning with moderate concentrations present, reducing air quality.
What you need to know
— Saharan Dust Surges: The ongoing surge of Saharan Dust is forecast to linger across Trinidad and Tobago through the end of the upcoming week, at least through Friday, October 13th, 2023. Mostly dust-free days are forecast through October 19th, 2023, when the next surge is forecast to arrive.
— Impacts: Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate.
— What Should You Do: Sensitive groups are advised to take the necessary precautions, particularly during high traffic periods and in the vicinity of bushfires.
Current AQI Levels Across T&T
The official air quality monitoring stations from the Environmental Management Agency (EMA) at San Fernando, Point Lisas, and Arima are reporting moderate air quality levels. Stations at Beetham, and Signal Hill, Tobago, are not reporting PM2.5 or PM10 data as of Saturday afternoon.
These measurements are based on PM2.5 (particulates the size of 2.5 micrometers and smaller, usually associated with increases in Saharan Dust, vehicle exhaust, and smoke) and PM10 particulates.
Over the last 24 hours, visibility remained unaffected by Saharan Dust and smoke at the A.N.R. Robinson International Airport at Crown Point, Tobago, and at the Piarco International Airport, Trinidad.
Saharan Dust Forecast
Following the passage of Tropical Wave 49, as forecast, a surge of Saharan Dust has moved across Trinidad and Tobago and the Lesser Antilles, with gradually increasing levels through Monday, October 9th, 2023. Overall higher dust levels are forecast to remain north of Trinidad and Tobago.
Concentrations are forecast to fluctuate between mild and moderate levels through Friday, October 13th, 2023, with little to no dust forecast by the end of next week into the weekend.
Longer range modeling, outside of this 10-day forecast period, suggests a surge of Saharan Dust arriving across the region sometime after October 18th/19th.
Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate. Air quality may be further reduced in the vicinity of bush or landfill fires.
What does this mean for you?
We’re in a period where the Intertropical Convergence Zone and tropical waves and occasional tropical cyclones may shield Trinidad and Tobago from the Saharan Dust events. While tropical waves play a notable role in moving dust across the Atlantic and the Eastern Caribbean, these periodic tropical waves also improve air quality.
The concentration of the dust that follows the wave depends on its strength as it moves off the West African Coast. This is because of stronger thunderstorms across Central Africa. As strong winds move downward and outward from these thunderstorms, the wind kicks up dust as it moves across parts of the Saharan Desert and transports it into the upper atmosphere. This “plume” of dust follows the axis of the wave as it progresses westward into the Atlantic.
Dust that makes it into the upper levels of the atmosphere can then get transported across the Atlantic Ocean. The plumes of dust eventually affect the Eastern Caribbean.
Larger, more concentrated plumes of Saharan dust begin in April and continue through November.
