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Productivity Increases

Range Expansions

Dozens of studies of historical trends of forest productivity have shown tree growth the world over to have risen hand-in-hand with the upward trend in the air's CO2 content that began with the dawning of the Industrial Revolution, with some of the studied tree species actually doubling their growth rates over this time period.  Even in highly-productive tropical forests is this phenomenon evident; and it has been demonstrated to have accelerated in recent decades.  Concurrently, dozens of studies from every corner of the globe have revealed that the ranges of forests have also increased, particularly where they have not been curtailed by the actions of man. 

Both of these CO2-induced phenomena are manifestations of the unprecedented botanical transformation of the planet that is lifting Earth's biosphere out of the low-productivity state it has occupied for the past six to eight million years of uncommonly low atmospheric CO2 concentration and restoring it to the high-productivity state that it occupied over the prior 400-million-year period of much higher atmospheric CO2 concentration.



** For additional peer-reviewed scientific references and an in-depth discussion of the science supporting our position, please visit Climate Change Reconsidered: The Report of the Nongovernmental Planel on Climate Change (, or CO2 Science (