Land-Atmosphere Interaction : Vegetation Feedback P. Friedlingstein Stephen Guendert Arts & Sciences Climatic Studies 4/1/15

Contents About Friedlingstein 2006 Paper intro Data/Results Conclusion 2010 Paper intro Data/Results Conclusion Questions

Professor Pierre Friedlingstein Research interests in the field of global carbon and global biogeochemical cycles More specifically interested in time scales towards the future in IPCC like projections Numerous key publications Member of Global Carbon Project and actively participates With the ICCP

Introduction (2006) Atmospheric CO2 concentration is one of the most important factors likely to determine the climate of the twenty-first century. In context of future climate change, carbon cycle simulations have been extensively performed and compared to one another in terms of outcomes and scenarios

First, What is the Carbon Cycle?

Intro (continued) Climate change simulations showed a reduced terrestrial carbon sink in all models as a result of impacts on net ecosystem productivity of tropical and Southern Hemisphere ecosystems Models indicate that the carbon cycle feedback is positive in the future. Higher temperatures due to warmer climate leads to less CO2 being abosrbed which in turn leads to more being in the atmosphere

Data

Results All models showed larger amounts of CO2 by the year 2100 All models present indicated positive climate-carbon cycle feedback, indicating the continued growth of atmospheric CO2 More atmospheric CO2 the hotter it gets…

Results Currently our atmospheric concentration is… In the simulations of atmospheric CO2 concentrations for 2100 are predicted to be…

Conclusion Although the prediction models look rather grim, we can always have an influence and try to steer ourselves to the better of the predictions. We each have the power to try and change these!

Intro (2010) Atmospheric content of long lived GHG represents balance between anthropogenic emission and natural sources and sinks. Human induced emissions of GHG have increased substantially in the last 2-3 centuries since the Industrial Revolution.

Intro (continued) It has long been recognized that the change in atmospheric concentration has induced change in the natural sink strengths Decadal Avg. is that 55% of anthropogenic CO2 is absorbed while 45% remains in the atmosphere

Data

Results Based on the graphs, we can see that CO2 variability is based on ENSO time scales and will go up or down during these time periods. Even with this correlation, we are still emitting too much CO2 in the atmosphere for us to be considered at a natural level with ENSO variations.

Results We are able to predict the climate from our past with ice core archives that are taken from around the world From these we can see the natural rises and falls of CO2 concentration and have been able to identify that we have made an impact (negatively) on the atmosphere.

Conclusion With the amount of atmospheric CO2 emitted, we have disturbed the natural process in which the Earth has had for numerous years. Based on the data collected we have been able to identify us as the source of this disturbance

References (picture) (picture) _even_the_dog_starts_to_melt/ (picture) (picture) Intergovernmental Panel on Climate Change, Climate Change 2001: The Scientific Basis (U.K., 2001) Friedlingstein et al (2006) Friedlingstein et al (2010)