Seasonal variations in sulfate, nitrate and chloride in the greenland ice sheet: Relation to atmospheric concentrations

摘要: Samples from three snowpits near Dye 3 in South Greenland have been used to study seasonal variations contaminant transport the atmosphere Ice Sheet. The cover years 1982–1987. samples dated by comparing δ18O values with meteorological data 3. Airborne concentrations of SO2−4 over Sheet estimated for dates corresponding each snowpit sample statistically analyzing several air monitoring stations throughout Arctic, and computing average appropriate stations. Seasonal air, snow, mass-basis scavenging ratios (concentration snow divided concentration air) identified. Results indicate that SO2−4in show a strong peak late February, resulting long-range mid-latitude anthropogenic emissions, while those broad January, February March smaller variation overall. is attributed part effect riming, which results more efficient during warm weather when airborne are low. importance riming also supported annual cycle ratio peaks mid-summer coincident maximum temperatures. In agreement previous estimates, dry deposition appears account 10–30% total snow. Concentrations NO−3 summer; natural material stratosphere as well emissions transported mid-latitudes may be responsible. Cl− relatively high October through July. winter believed reflect (LRT) marine aerosol north Atlantic storms, summer seaspray nearby coastal Greenland. Riming influence