Carbon Monoxide Concentration and Isotope Measurements in New - PowerPoint PPT Presentation

Carbon Monoxide Concentration and Isotope Measurements in New Zealand. Rowena Moss, Gordon Brailsford, Martin Manning and Hinrich Schaefer. National Institute of Water and Atmospheric Research.

Raoul Island Baring Head: 41.41°S, 174.87°W Rainbow Mountain Baring Head Lauder Arrival Heights

GC-CVAFS GC CVAFS Detector Rotometer Heated Main column HgO Bed Pre-column 5 4 6 3 7 2 8 1 Vent 9 10 Purge 1mL sample loop O vent 2 Out In Argon carrier

• Seasonal maximum in September (austral spring) • Seasonal minimum in February (austral summer) • Seasonal Amplitude decrease from 40ppb to 30ppb

CO 2 CO

35 CO sources- isotope signatures d18O Technological 25 Savanna burning ch4 oxidation 15 Forest burning 5 d13C -55 -45 -35 -25 -15 -5 5 15 -5 Terpene Ocean -15 NMHC Isoprene -25 -35

• Seasonal maximum in March Seasonal minimum • in late November • Seasonal Amplitude decrease from 6‰ to 4.5 ‰

• Seasonal maximum in March Seasonal minimum • in September • Seasonal Amplitude decrease from 8‰ to 5 ‰

• Seasonal maximum in September Seasonal minimum • in March

Summary • Observed decrease in CO concentrations in the Southern Hemisphere • Changes in sources such as savanna and forest burning and CH 4 oxidation can be observed in δ 13 CO • 14CO can be used to infer variations in OH

NIWA TROPAC team Mike Harvey Zoë Buxton Gordon Brailsford Sara Mikaloff- Fletcher Peter Sperlich Andrew Marriner Rowena Moss Ross Martin Sylvia Nichol Kay Steinkamp John McGreggor Hinrich Schaeffer Tony Bromley