From today, a major Saharan Dust surge is forecast to begin moving across Trinidad, Tobago and the Lesser Antilles, with peak concentrations from Tuesday through Thursday this week across T&T. This surge is forecast to be more concentrated compared to the Christmas 2023 surge across the Windwards and T&T, which brought unhealthy air quality to the country, and reduced visibly to 5 kilometers.
What you need to know
— Saharan Dust Surges: From late January 29th, 2024, a significant Saharan Dust concentration surge is forecast to move across Trinidad and Tobago, spreading across the Lesser Antilles. Peak concentrations are forecast on January 30th into February 1st.
— Impacts: Between January 29th and February 1st, air quality across T&T will range between moderate and unhealthy. From February 1st, air quality will remain mostly at moderate levels, occasionally reducing to levels that are unhealthy for sensitive groups.
— What Should You Do: Particularly between January 29th through February 1st, everyone should take the necessary precautions. Thereafter, unusually sensitive groups are advised to take the necessary precautions, particularly during high traffic and in the vicinity of fires.
Current AQI Levels Across T&T
The official air quality monitoring stations from the Environmental Management Agency (EMA) at San Fernando and Arima report good air quality levels, Point Lisas is reporting moderate air quality levels, and at Beetham, Port of Spain, air quality is unhealthy for sensitive groups. As of Monday morning, the station at Signal Hill, Tobago, is not reporting PM2.5 or PM10 data.
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
A major surge of Saharan Dust is forecast to move across Trinidad and Tobago from today, Monday, January 29th, 2024, with concentrations increasing through today and peaking on Tuesday through Thursday.
Concentrations will gradually decline over the next ten days, but another moderate surge is forecast to move in by February 7th into February 8th.
Based on the latest forecast models, concentrations are forecast to be higher than what was experienced during Christmas 2023, when air quality was reduced to unhealthy levels, and visibility was reduced to 5 kilometers.
Between January 29th and February 1st, air quality across T&T will range between moderate and unhealthy. From February 1st, air quality will remain mostly at moderate levels, occasionally reducing to levels that are unhealthy for sensitive groups. Air quality may be further reduced near bush or landfill fires or during high-traffic periods. As drier conditions are forecast, there will be an increased risk of fires.
What does this mean for you?
Everyone may begin to experience health effects, and members of sensitive groups may experience more serious health effects. Everyone should take the necessary precautions, particularly between January 30th and February 1st, when peak concentrations are forecast.
From February 2nd, air quality is forecast to gradually improve across Trinidad and Tobago as higher concentrations of Saharan Dust move westward. However, with elevated concentrations still present and drier conditions bringing the risk of fires, air quality is still forecast to be reduced, with further reductions in localized areas of fires, blowing smoke and dust, and high traffic.
During this period, a ridge of high pressure stays over the central Sahara Desert, and the Intertropical Convergence Zone (ITCZ) remains over the Gulf of Guinea. The Harmattan wind accelerates when it blows across the mountain massifs of Northwest Africa. If its speed is high enough and it blows over dust source regions, it lifts the dust and disperses it.
The surges of dust during this time of year are due to the Harmattan, a season in the West African subcontinent that occurs between the end of November and the middle of March. During this season, a predominant northeasterly trade wind (dubbed the Harmattan Winds) blows from the Sahara Desert over Western Africa into the Gulf of Guinea.
Dust that makes it into the upper levels of the atmosphere can then get transported across the Atlantic Ocean and affect the Eastern Caribbean. These Saharan Dust outbreaks tend to be milder in the Eastern Caribbean than the dust outbreaks.
