The Bad News
1. Emissions are bad
Greenhouse gas emissions (GHG) from human sources are the main problem. We are dumping 40 billion tonnes of carbon dioxide and other GHG into the atmosphere each year. That has raised average global temperatures by about +0.2°C per decade over the past 40 years. Recently warming has reached +0.3°C per decade.
It doesn’t sound like much, but you should think about global temperature like you think about your own body’s. At 36.8°C you feel fine, at 39°C you are running a fever, and at 43°C you’re dead. The Earth System is equally sensitive.
The ‘never-exceed’ temperature after which very bad things start to happen, according to the Intergovernmental Panel on Climate Change, is +2.0°C. Average global temperature in the past year has
