Ozone destruction and photochemical reactions at polar sunrise in the lower Arctic atmosphere

摘要: There is increasing evidence that at polar sunrise sunlight-induced changes in the composition of lower Arctic atmosphere (0–2 km) are taking place important regarding tropospheric cycles ozone, bromine, sulphur oxides1, nitrogen oxides2 and possibly iodine3. Here we focus on recent ground-level observations from Canadian baseline station Alert (82.5° N, 62.3° W) aircraft show ozone destruction occurring under surface radiation inversion during March April as Sun rises. The might be linked to catalytic reactions BrOx radicals photochemistry bromoform, which appears have a biological origin Ocean. This may clarify previously unexplained regular springtime occurrences depletion ground level 10-year data record Barrow, Alaska4, well peaks aerosol bromine observed throughout April3. Current information does not allow us offer more than speculative explanation for chemical mechanisms leading these phenomena.