PM10 concentration, Dakar Bel Air, Senegal

Atmospheric concentrations of Particulate Matter smaller than 10 µm (PM10) are measured using a Tapered Element Oscillating Microbalance (TEOM 1400A from Thermo Scientific) equipped with a PM10 inlet (Thermo Scientific). The TEOM is installed in the campus ISRA / IRD (Institut Sénégalais de Recherches Agricoles / Institut de Recherche pour le Développement) at Dakar Bel Air, which is located at about 300 m from the port and the sea. The inlet is located at 6.75 m above the ground level (about 1.75 m height from the flat roof of the building). The microbalance is installed in an air-conditioned room (about 3 m vertically below the PM10 inlet) to maintain ideal conditions for the TEOM sensor and control units. The lower part of the sampling tube (60 cm length) and the measurement chamber of the TEOM are heated at a temperature of 50°C (this heating allows a thermal stability of the particles and the filter, and minimize water condensation interferences, but it may induce a loss of a part of the most volatile particulate compounds, such as ammonium nitrates or condensate organic compounds). The flow rate is 3 L/min. The concentrations in micrograms per cubic meter (µg/m3) are recorded as 5 min averages and distributed as 1 hour averages (UTC). The value reported for 01:00UTC represents the average over the past hour, and so on (the number of values used to compute the average is given for each time step).