Global carbon cycle dynamics as revealed by long-term observation time series

2nd June 2022 | 9.50 am – 10.20 am

Hans-Knöll-Straße 10, 07745 Jena, Germany
BGC Lecture Hall
Zoom: will be provided

Session 1 – Long-term observations of change (Martin Heimann, moderator)
2nd June 2022 | 9.45 am – 11.40 am


At the forefront of the study of changes in global biogeochemistry are time-series observations of atmospheric CO2, isotopes of CO2 and related species, such as O2 and carbonyl sulfide (COS).  These records now span many decades, revealing variability on seasonal, secular and other time frames that has framed our understanding of global and continental carbon sources, rates of photosynthesis and respiration of both land and oceanic ecosystems, and rates of air-sea exchange.  In recent decades, these records have played a major role in clarifying the large role the land biosphere in modulating atmospheric CO2 and providing evidence for large increase in global land photosynthesis.  This talk will highlight major milestones over the past 6 decades and also showcase several new applications, such as constraining fossil-fuel and land use emissions and improving understanding of natural decadal variability in CO2.


Ralph Keeling’s work centers on long-term measurements of the major constituents in air.  He has been on the faculty at the Scripps Institution of Oceanography, UC San Diego, since 1993.  He was the first to demonstrate that the O2 content of air is decreasing due to the burning of fossil-fuels and has directed a program to track this decrease since 1989.  Since 2005 he has also directed the Scripps CO2 program which sustains the iconic record of carbon dioxide at Mauna Loa and other sites, begun by his father, Charles D. Keeling. He is engaged in ongoing research to refine estimates of sources and sinks of carbon dioxide using atmospheric measurements. Keeling has received the Rosenstiel Award in marine and atmospheric chemistry, the Humboldt Research Award, and is a Union Fellow of the American Geophysical Union. 

Official Website of Ralph Keeling