Doubling Down on Our Faustian Bargain

by James Hansen, Pushker Kharecha, Makiko Sato

Faust in his Study by Rembrandt
Humanity is doubling down on its Faustian climate bargain by pumping up fossil fuel particulate and nitrogen pollution. The more the Faustian debt grows, the more unmanageable the eventual consequences will be. Yet there are plans to build more than 1000 coal fired power plants and plans to develop some of the dirtiest oil sources on the planet. These plans should be vigorously resisted. We are already in a deep hole -- it is time to stop digging.

Humanity's Faustian climate bargain is well known. Humans have been pumping both greenhouse gases (mainly CO2) and aerosols (fine particles) into the atmosphere for more than a century. The CO2 accumulates steadily, staying in the climate system for millennia, with a continuously increasing warming effect. Aerosols have a cooling effect (by reducing solar heating of the ground) that depends on the rate that we pump aerosols into the air, because they fall out after about five days.

Aerosol cooling probably reduced global warming by about half over the past century, but the amount is uncertain because global aerosols and their effect on clouds are not measured accurately. Aerosols increased rapidly after World War II as fossil fuel use increased ~5%/year with little pollution control (Fig. 1). Aerosol growth slowed in the 1970s with pollution controls in the U.S. and Europe, but accelerated again after ~2000.

The rapid growth of fossil fuel CO2 emissions in the past decade is mainly from increased coal use (Fig. 1), mostly in China with little control of aerosol emissions. It is thus likely that there has been
an increase in the negative (cooling) climate forcing by aerosolsin the past decade, as suggested by regional aerosols measurements in the Far East, but until proper global aerosol monitoring is initiated, as discussed below, the aerosol portion of the amplified Faustian bargain remains largely unquantified.

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