title: Atmospheric O2, CO2 and delta13C measurements from aircraft sampling over Griffin Forest, Perthshire, UK.
abstract: Regular vertical aircraft sampling has been performed in the lower troposphere above Griffin Forest, near Aberfeldy, Perthshire, UK (56 degrees 37'N, 3 degrees 47'W), between February 2003 and May 2004, for analysis of O2/N2, CO2 and delta13C of CO2. We sampled flasks between 800 and 3100 m above sea level. The peak-to-peak amplitude of the seasonal cycle of O2/N2 decreases from 171 per meg at 800 m to 113 per meg at 3100 m. Furthermore, the seasonal cycle is shifted from low to high altitudes with a lag of about 1 month. The same features are observed for CO2 with a decrease in the peak-to-peak amplitude of the seasonal cycle from 17.6 ppm at 800 m to 11.4 ppm at 3100 m. The vertical profiles show decreasing O2/N2 ratios in summer and increasing O2/N2 ratios in wintertime with increasing sampling height, due to surface exchange of oxygen with the land biosphere and the ocean. The O2:CO2 exchange ratios of the vertical profiles vary between -1.5 and -2.4 mol O2/mol CO2.
authors.affiliation: Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland.
authors.forename: Patrick
authors.initials: P
authors.lastname: Sturm
authors.forename: Markus
authors.initials: M
authors.lastname: Leuenberger
authors.forename: John
authors.initials: J
authors.lastname: Moncrieff
authors.forename: Michel
authors.initials: M
authors.lastname: Ramonet