The 1000-ton rule says that a future person is killed every time humanity burns 1000 tons of fossil carbon. It is derived from a simple calculation: burning a trillion tons of fossil carbon will cause 2 °C of anthropogenic global warming (AGW) [57,58], which in turn will cause roughly a billion future premature deaths spread over a period of very roughly one century [59]. On the assumption that 2 °C of warming is either already inevitable (given the enormous political and economic difficulties of achieving a lower limit) or intended (given that the business plans of big fossil fuel industries make it inevitable), it can be concluded that burning 1000 tons of fossil carbon causes one future premature death.
They’re predicting that a billion people are going to die if we burn a trillion tons of carbon, so the ratio of tons of carbon burned to predicted deaths is 1000 to 1. They don’t make any mention of how they concluded that a billion people were going to die. So the 1000 ton rule is only as good as their estimate of how many people would die due to an increase of 2 degrees centigrade due to AGW. It seems a little flimsy without knowing how they arrived at the conclusion that an increase of 2 degrees centigrade due to AGW would result in the deaths of 1 billion people. I’ll have to look at that in the morning.
https://www.mdpi.com/1996-1073/16/16/6074
They’re predicting that a billion people are going to die if we burn a trillion tons of carbon, so the ratio of tons of carbon burned to predicted deaths is 1000 to 1. They don’t make any mention of how they concluded that a billion people were going to die. So the 1000 ton rule is only as good as their estimate of how many people would die due to an increase of 2 degrees centigrade due to AGW. It seems a little flimsy without knowing how they arrived at the conclusion that an increase of 2 degrees centigrade due to AGW would result in the deaths of 1 billion people. I’ll have to look at that in the morning.