Isotope climatology of Canada: Insights from the first decade of CNIP operation (1997- 2007)
Abstract
The Canadian Network for Isotopes in Precipitation (CNIP) was initiated as a joint venture between university and government researchers to provide the spatial and temporal data necessary to examine the sensitivity of isotope fields to changes in circulation patterns. The network consists of 17 stations distributed across Canada, spanning almost 40° of latitude and 70° of longitude collecting weighted monthly precipitation samples. This marks the first time that both the southern and northern regions of the country have been simultaneously sampled. Sampling of the southern stations was initiated in 1997 to supplement an existing informal arctic network (now formally incorporated in CNIP) resulting in a 10-year dataset for the entire country. The sensitivity of isotope-climate signals to modes of interannual variability such as El Nino-Southern Oscillation, North Atlantic Oscillation, Arctic Oscillation, and the Pacific North American pattern is of interest because they are a primary cause of interannual climate variability. The ten-year dataset includes some intriguing results that reveal the complexity and dynamic nature of isotope-climate relations in Canadian precipitation. Time-series of the CNIP dataset include anomalously low d-excess values during the 1997-98 El Nino at southern stations located across the entire country, suggesting a wide-reaching influence of this mode of climate variability on precipitation labeling. Correlations between and isotope time-series and various circulation indices show strong regional controls on isotope-climate relations.
- Publication:
-
AGU Spring Meeting Abstracts
- Pub Date:
- May 2009
- Bibcode:
- 2009AGUSMCG14A..02B
- Keywords:
-
- 1041 Stable isotope geochemistry (0454;
- 4870);
- 1833 Hydroclimatology;
- 1848 Monitoring networks;
- 1854 Precipitation (3354)