Although most of the focus on climate change has centered on the warming effects of fossil fuels beginning with the fairly recent industrial era, new research highlights the start of global warming thousands of years ago when forests were cleared to create room for livestock and other agriculture.
These changes are evident in the ice cores of Greenland and Antarctica, which show increases in carbon dioxide levels related to the burning and decay of cleared forests and meadowlands.
For the study, researchers from Carnegie Institution's Department of Global Ecology in California, USA and from the Max Planck Institute for Meteorology in Germany used a model of global land coverage beginning around 800 AD. To determine how reforestation might affect atmospheric carbon dioxide levels, they focused on four times in history when human populations decreased due to either conflict or disease, with agricultural fields thus being abandoned.
These periods of minimized human activity were found to create a cooling effect as the forests were naturally restored and resumed absorption of CO2 from the atmosphere. Lead author Dr. Julia Pongratz explained the modern implication of such reforestation on planetary cooling as she stated, “Today about a quarter of the net primary production on the Earth's land surface is used by humans in some way, mostly through agriculture… Based on the knowledge we have gained from the past, we are now in a position to make land-use decisions that will diminish our impact on climate and the carbon cycle.”
Many thanks, Dr. Pongratz and colleagues, for your work in revealing the profoundly beneficial effects of reforestation in mitigating climate change. Let us do our utmost to minimize destructive tree losses by halting livestock-raising and other unsustainable agricultural practices for the protection of our planet.
In a video message presented at a June 2009 conference with dignitaries in Mexico, Supreme Master Ching Hai addressed the importance of conserving the world's vital forests as well as a way that this could be done.