Journal
ATMOSPHERIC ENVIRONMENT
Volume 41, Issue 39, Pages 9091-9098Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.atmosenv.2007.08.008
Keywords
baseline mixing ratios; surface ozone; long-term trends; biomass burning
Ask authors/readers for more resources
Hourly measurements of baseline ozone at the Mace Head Atmospheric Research Station on the Atlantic Ocean coast of Ireland are observed when unpolluted air masses are advected to the station from across the North Atlantic Ocean. Monthly mean ozone mixing ratios in baseline air masses have risen steadily during the 1980s and 1990s reaching unprecedented levels during the early months of 1999. During the 2000s, baseline ozone mixing ratios have shown evidence of decline and stabilisation. Over the entire 20-year 1987-2007 period, the trend in annual baseline ozone has been + 0.31 +/- 0.12(2-sigma) ppb year(-1) and is highly statistically significant. Trends have been highest in the spring months and lowest in the summer months, producing a significant increase in the amplitude of the seasonal cycle. Over the shorter 1995-2007 period, we demonstrate how the growth to peak in 1999 and the subsequent decline have been driven by boreal biomass burning events during 1998/1999 and 2002/2003. The 2000s have been characterised by relatively constant baseline ozone and CH4 levels and these may be a reasonable guide to future prospects, at least in the short term. (C) 2007 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available