Nearly all islands across the Southern French Antilles and the Windward Islands are experiencing moderate air quality levels as of 1:00 PM Wednesday 3rd July 2019. A vigorous tropical wave is forecast to begin affecting the entire Lesser Antilles on Thursday but will bring a mild surge of Saharan Dust on Saturday into Sunday. Concentrations of Saharan dust forecast to fluctuate between minimal and mild over the next 5 days, with air quality remaining between good and moderate.
Presently, mild to moderate concentrations of Saharan Dust are present across Trinidad and Tobago, with air quality at moderate levels.
Air Quality Index at Environmental Management Agency‘s (EMA) Air Quality Monitoring Stations Across Trinidad. Note these AQI values are to Trinidad and Tobago air quality standards.
Generally, across the Leewards and the Greater Antilles, air quality is good. However, across the Southern Windwards, and parts of the French Antilles, air quality is at moderate levels as this plume of Saharan Dust moves out of the Eastern Caribbean.
Moderate Air Quality
AQI – 51 to 100
What does this mean for you?
Air quality is acceptable; however, for some pollutants, there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
Who needs to be concerned?
Unusually sensitive people: Consider reducing prolonged or heavy exertion. Watch for symptoms such as coughing or shortness of breath. These are signs to take it easier.
Everyone else: It’s a good day to be active outside.
What should you do?
Sensitive Groups: Sensitive groups such as those with respiratory ailments, children and the elderly are advised to reduce outdoor physical exertion, and reduce the time of their stay outdoors, especially in areas with heavy traffic.
Air purification: At this level, the air is slightly polluted. It is recommended to turn on your air purifier, running at a low level, at a minimum.
Ventilation: Please close windows, as the air is slightly polluted.
Masks: Wearing a mask during outdoor activity is recommended, particularly in areas with heavy traffic.
Outdoor Activity: It is recommended to stay indoors and avoid outdoor exercise.
The concentration of the dust that follows the wave depends on the strength of the wave 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.
Larger, more concentrated plumes of Saharan dust begin to occur in April and continue through November.
Good news for folks who suffer from Saharan Dust with this latest tropical wave! Tropical waves, combined with the ITCZ begin to shield Trinidad and Tobago from these dust plumes as they move across the Atlantic. While mild to moderate surges are still forecast following the passage of tropical waves, these dust events are generally forecast to be short-lived and primarily affect islands north of T&T.
Dust models continue to show, following the passage of tropical waves, mild to moderate concentrations of Saharan Dust moving across Trinidad and Tobago over the next several weeks. Based on the latest model guidance, a mild surge is forecast by late Saturday, with a more moderate surge forecast later next week, following the passage of Tropical Wave 16.
Sensitive groups such as persons with respiratory ailments, children, the elderly and cardiopulmonary disease should take the necessary precautions on days where dust concentrations degrade air quality to moderate to unhealthy for sensitive groups.