Tag Archives: ken caldeira

War, Plague No Match for Deforestation in Driving CO2 Buildup

Stanford, CA —  Genghis Khan and his Mongol hordes had an impact on the global carbon cycle as big as today’s annual demand for gasoline. The Black Death, on the other hand, came and went too quickly for it to cause much of a blip in the global carbon budget. Dwarfing both of these events, however, has been the historical trend towards increasing deforestation, which over centuries has released vast amounts of carbon dioxide into the atmosphere, as crop and pasture lands expanded to feed growing human populations. Even Genghis Kahn couldn’t stop it for long. (more…)

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Optimizing Climate Change Reduction

Palo Alto, CA — Scientists at the Carnegie Institution’s Department of Global Ecology have taken a new approach on examining a proposal to fix the warming planet. So-called geoengineering ideas—large-scale projects to change the Earth’s climate—have included erecting giant mirrors in space to reflect solar radiation, injecting aerosols of sulfate into the stratosphere making a global sunshade, and much more. Past modeling of the sulfate idea looked at how the stratospheric aerosols might affect Earth’s climate and chemistry.

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Main Climate Threat from CO2 Sources Yet to Be Built

Stanford, CA — Scientists have warned that avoiding dangerous climate change this century will require steep cuts in carbon dioxide emissions. New energy-efficient or carbon-free technologies can help, but what about the power plants, cars, trucks, and other fossil-fuel-burning devices already in operation? Unless forced into early retirement, they will emit carbon dioxide into the atmosphere for decades to come. Will their emissions push carbon dioxide levels beyond prescribed limits, regardless of what we build next? Is there already too much inertia in the system to curb climate change?

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