ALT and PTB Stations Isotopic 13C Trends
Description
Black Dots: Monthly average atmospheric Isotopic 13C concentration versus time at stations in the Northern and Southern Hemispheres where 13C concentration is in parts per million in the mole fraction (p.p.m.).
Black Curves: The sum of 4 seasonal harmonics and a spline function to the stations 13C concentration data. The seasonal harmonics include a linear gain factor, to represent increasing amplitude with time.
Station code names are as follows: ALT = Alert, NWT, Canada, and PTB = Utqiagvik (formerly Barrow).
Data from Scripps CO2 Program.
Usage Restrictions
Scripps CO2 program data and graphics on scrippsco2.ucsd.edu are licensed under a CC BY license, Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which clarifies appropriate uses and requirements, including that credit be given to the Scripps Institution of Oceanography at UC San Diego. Some products from this site incorporate data from sources external to the Scripps CO2 program, as indicated. Additional credit must be given for these products, as appropriate for that source.
Ethical usage may also require disclosing intentions at early stages to avoid duplicating ongoing studies at Scripps or elsewhere. For applications supporting peer-reviewed scientific publications, coauthorship may sometimes be appropriate. An example would be if an important result or conclusion depends on this product, such as the first account of a previously unreported phenomenon.
Please direct queries to Ralph Keeling (rkeeling@ucsd.edu)