South African integrated carbon observation network (SA-ICON): CO2 measurements on land, atmosphere and ocean

Abstract

It has become essential to accurately estimate the emission and uptake of atmospheric carbon dioxide (CO(sub2)) around the globe. Atmospheric CO(sub2) plays a central role in the Earth’s atmospheric, ocean and terrestrial systems and it has been recognised as the greatest contributor to the anthropogenic greenhouse gas effect. Increasing atmospheric CO(sub2) concentrations have widespread impact on human and natural systems, such that the last three decades have had successively warmer surface temperatures than any preceding decade in the industrial age. Furthermore increasing energy in the climate system has resulted in increased surface ocean warming and decreasing pH, loss of ice mass over the cryosphere (Greenland and Antarctica), increasing global mean sea level, alterations in the global hydrological cycle (changing precipitation, evapotranspiration and melting snow) through increased moisture in the atmosphere. The impact on the biosphere includes shifting species geographic extent, seasonal activities, migration patterns, and abundances as well as species interactions. Roughly 40% of the total anthropogenic emissions since 1750 have remained in the atmosphere, with the balance being removed by the ocean and vegetation sinks. It has become essential for individual countries to develop strategies to reduce emissions, and accurately monitor their national inventories of the carbon cycle. Understanding the changing driving forces of climate change and evaluation of the carbon emission reduction activities requires long-term and high precision measurements of CO(sub2) gas emissions and sinks as well as their evolution. Long term observations are required to understand current and future behaviour of the carbon cycle, as well as the assessing the effectiveness of carbon emission reduction activities on regional atmospheric CO(sub2) levels. This project aims at setting up an integrated national network of CO(sub2) observation facilities to independently measure both the atmospheric concentrations of CO(sub2) over South Africa and the Southern Oceans and the fluxes of CO(sub2) between the atmosphere and the terrestrial and marine ecosystems. A description of the monitoring network and preliminary results will be presented.