A statistical comparison of the CO₂ measurements at Cape St. James and Station “P”, Canada

Abstract

As part of the Canadian CO₂ monitoring program, a CO₂ flask sampling program was initiated at Cape St. James, Canada in May, 1979. The site was to become the replacement station for Ocean Weather Station “P” (located in Gulf of Alaska), which was terminated in June, 1982. In order to compare the Cape St. James data to the Station “P” data, we have examined the statistical properties of the CO₂ measurements taken at these two stations. Both stations show very similar climatological CO₂ seasonal cycle, with an amplitude of about 13 ppmv. Seasonal minimum occurs at the same time at both sites (late August). Furthermore, CO₂ measurements at both locations indicate greater variability in summer than in winter. Cape St. James shows greater variability than Station “P” in winter (statistically significant), while the opposite is true in summer (not statistically significant). Based on the analysis, we have concluded that Cape St. James was a good replacement choice for Station “P”.