After somewhat of a dusty start to September, Saharan Dust concentrations are forecast to decline from Wednesday, with little to no dust expected by the weekend. Occasional mild to moderate surges are possible from next week.
What you need to know
— Saharan Dust Surges: A moderate Saharan Dust surge is forecast to move away from Trinidad and Tobago by early Wednesday, September 6th, 2023, with mild concentrations lingering through early Friday, September 8th, 2023. A mild to moderate surge is forecast to return the subsequent week, Friday, September 15th, 2023.
— 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 should take the necessary precautions through early Wednesday and again from Friday, September 15th, 2023.
Current AQI Levels Across T&T
The official air quality monitoring stations from the Environmental Management Agency (EMA) at Point Lisas, San Fernando, and Arima are reporting moderate quality levels. Stations at Beetham and Signal Hill, Tobago, are not reporting PM2.5 or PM10 data as of midnight Tuesday.
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
Saharan Dust levels remain at moderate levels on Tuesday, but from early Wednesday, September 6th, 2023, dust levels are forecast to decline with little to no dust forecast by Friday, September 8th, 2023, and remain at negligible levels through Sunday, September 10th, 2023.
A mild to moderate surge is forecast on Sunday morning and will linger through Tuesday, September 12th, 2023, during the afternoon, with higher dust levels remaining north of T&T.
Another period of negligible dust is forecast through late Thursday, September 14th, 2023, with a mild to moderate surge returning across T&T by Friday, September 15th, 2023.
Through the next seven to ten days, air quality levels across Trinidad and Tobago are forecast to remain between good and moderate. Sensitive groups should take the necessary precautions, particularly through Wednesday, and again during the aforementioned periods of Saharan Dust surges.
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.
