Mapping global CO2

Impact: Development of a new model for better estimates of atmospheric CO2

Knowing where CO2 is emitted (sources) and where it is absorbed (sinks) is a challenge facing scientists and policymakers across the globe.

Mapping these CO2 sources and sinks, or fluxes, in a statistically optimal manner and at a high geographical resolution will improve our understanding of the extent of CO2 emissions caused by humans and its effect on our climate.

Currently, our knowledge is limited by the lack of reliable globally distributed CO2 measurements that would allow estimation of near-surface CO2 sources and sinks.

These estimates need to be sufficiently localised to allow carbon-cycle scientists to infer where the cycling of CO2 occurs over different seasons. UOW researchers are helping to solve this problem by developing a statistically optimal global map of atmospheric CO2 at high geographic resolution.

Distinguished Professor Noel Cressie is working on a spatial statistical model to estimate CO2 in atmospheric columns at any location on the globe, followed by an estimate of near-surface fluxes and a statistical analysis of the uncertainties associated with these estimates.

The uncertainties are fundamental to making probabilistic scientific inference on the near-surface CO2 sources and sinks.

This work is closely tied to the launch in July 2014 of NASA’s Orbiting Carbon Observatory-2 satellite, which is yielding unprecedented atmospheric-column CO2 measurements in terms of both high geographic resolution and data volume.

Providing a solution for the mapping of near-surface CO2 fluxes within a global measurement and transport model will lead to a better grasp of the impact carbon dioxide emissions have on our climate and environment, and thus the impact they have on, for example, the future of crop yields, species distribution, and extreme weather events.

It also has significance for controlling atmospheric CO2 through international carbon treaties and markets for carbon trading.