Long-term hourly measurements of dibromomethane in the atmosphere

Abstract

Dibromomethane(CH2Br2) and bromoform(CHBr3) are short-lived bromocarbons which are maily emitted from the ocean. These compounds are believed to contribute to 3-8ppt Br in the stratosphere. In this study, we conducted long-term hourly measurements of CH2Br2 in the atmosphere at Hateruma Island for seven years, and at Cape Ochiishi for five years. We discuss its seasonal variation, year-to-year trend, and its oceanic sources based on the measurements.