THE HOT ZONE
Last year, James Hansen, director of the National Aeronautics and Space Administration Goddard Institute for Space Studies and Adjunct Professor of Earth and Environmental Sciences at Columbia Universityâ€™s Earth Institute, wrote these words:
â€œOur home planet is dangerously near a tipping point at which human-made greenhouse gases reach a level where major climate changes can proceed mostly under their own momentum.â€
What does this mean? If the climate is a car weâ€™re driving on a mountain road, weâ€™ve arrived at its highest pass. We’re beginning our descent. But weâ€™ve neglected the brakes. The highway department never installed any guard rails alongside the sheer granite cliffs. And on top of this, we forgot to check the power steering fluid. If we canâ€™t steer, and we canâ€™t brake, and there are no railings, nothing is going to stop our fall.
With this blog, we’re hoping to establish a common goal: we must change our driving habits before it’s too late.
Here youâ€™ll read about how our biosphere is changing because of human activity. Weâ€™ll present science about the disappearance of the polar ice sheets, the carbon cycle, microbes, water vapor, climate engineering, even our prospects as terra-formers on other planets. Weâ€™ll discuss the latest research and interview scientists involved in climate change.
But this blog is not just about the scientists doing research. It is about you. We want you to think about now you live now. What changes are you making in your own life, the life of your family, and the life of your community to help stem the global warming tide?
We’re asking you to be self-reflective, and we’re asking for your feedback. We want you to read and learn and respond. The Hot Zone will be a place where serious people can have a serious discussion about climate change.
Get involved in reversing global warming before itâ€™s too late. It’s your planet.
Welcome to The Hot Zone.
My first climate science topic is about how a â€˜goodâ€™ greenhouse gas, carbonyl sulphide, blanketed the Archean Earth, causing the surface temperature to remain just warm enough for life to start.
Researchers in Denmark and Japan think they may have an explanation for why the Earth did not freeze over back when the Sun was about 30% weaker than it is now (about 3.5 billion years ago): carbonyl sulphide, produced by the countless volcanoes ejecting lava into the early atmosphere blanketed the Earth like a down comforter. The insulating effect of the gas compensated for lack of warmth emanating from the Sun.
As evolving life produced increasing levels of oxygen, it reacted with carbonyl sulphide, producing sulphate aerosols. Sulphate aerosols are powerful coolants, thought to be responsible for the creation of Snowball Earth, 2.5 billion years ago.
I asked Goddard Institute of Space Studies Scientist Linda Sohl to comment about whether carbonyl sulphide in the ancient atmosphere has any bearing on our understanding of climate change today. Hereâ€™s what she said:
â€œCarbonyl sulphide is a neat idea for early Earth, which had a very different chemical composition from todayâ€™s atmosphere. However, exploring the chemistry of sulphur in the atmosphere can help us think about the role sulphur may play in future climate change and ideas for geoengineering the climate.â€
Scientists are already experimenting with models to explore the effect man-made sulphate aerosols could have on our atmosphere. A chemical relative of carbonyl sulphide may one day be injected into the stratosphere to cool our planet once again.