Deposition Monitoring & Mapping
This Passive Monitoring program provides data on air quality at 20 sites in the region where power is not available. Passive devices for measurement of sulphur dioxide, nitrogen dioxide and ozone are collected monthly in spring, summer and fall, and every 2nd month in the winter. An additional 40 TEEM sites are equipped with ion exchange resin collectors, devices used to estimate deposition of substances from industrial and natural sources to ecosystems. TEEM continues to evaluate passive devices for additional substances as they become available.
Five solar-powered, 30-meter towers at forest health monitoring plots continuously measure meteorological conditions. Other instruments provide data on soil conditions. Data are streamed to the WBEA database using cell or satellite links. These data are necessary for proper interpretation of air quality and ecological monitoring data and can be used to improve region specific air quality model predictions.
Conditional Time Averaged Gradient:
WBEA’s Conditional time averaged gradient (CoTAG) instrument measures deposition velocities of compounds containing nitrogen and sulphur. Results are used to calibrate deposition models and estimate dry deposition.
Stable isotope signatures are employed to determine whether a link between specific natural and anthropogenic emission sources and deposition at TEEM sites can be made. Stable isotopes can also be used to trace the fate of these emissions in the terrestrial environment.