There are many ways to reconstruct CO2 in the past. The ice-cores from Anatarctica represent the highest fidelity archive but only cover the last 800 thousand years. To reach further back in time we need to use indirect methods called "proxies". These proxies need careful calibration and extensive validation.
The geological past contains a rich archive of examples of Earth's climate system operating in warmer or colder states than today. Palaeoclimate studies can provide valuable insights into how the system operates in these altered climate states, often with important implications for our warming future.
Changes in the concentration of atmospheric CO2 through the action of the carbon-cycle is a key driver of natural changes in climate. Therefore, to fully understand past climate change, and hence what it might mean for our future, we need accurate, precise, robust and high-resolution records of CO2 through geological time.
There are multiple proxies available with new ones being developed all the time. Each proxy has its own strengths, weaknesses and complications. Yet the independence of each proxy means a combined approach will provide the most accurate reconstruction provided the uncertainties for each proxy has been fully explored and calculated.
The aims of the paleo-CO2 project are:
- Compile and summarise the latest and best data for the expert and non-expert, and provide the latest understanding of each of the marine-based CO2 proxies.
- Provide discussion of why some records are discarded by the "experts" in favour of new data and provide the latest understanding of each proxy.
- Provide a set of validation criteria/targets for existing and emerging proxies.
- To highlight where existing proxy validation and inter-comparison efforts are occuring.
- To provide a forum for discussion regarding marine-CO2 proxy intercomparison, validation and calibration.
- A place to post the latest news about CO2 proxies, highlight the latest publications and to advertise community activities (e.g. conference sessions and meetings).