3 ms·

Thanks for the legwork. Would need to see the actual content of the predictions. But at least from your quote, the actual effects are not supposed to happen by

Thanks for the legwork. Would need to see the actual content of the predictions. But at least from your quote, the actual effects are not supposed to happen by the year 2000. It's just that the amount of CO2 emitted by year 2000 has already committed us to a certain amount of climate change, that will just take a while to happen. Here's one article with some actual sources, looking at predictions from the year 1981. https://www.skepticalscience.com/lessons-from-past-predictions-hansen-1981.html https://www.skepticalscience.com/lessons-from-past-predictio...

jessriedel 9y ago
> But at least from your quote, the actual effects are not supposed to happen by the year 2000. > It's just that the amount of CO2 emitted by year 2000 has already committed us to a certain amount of climate change, that will just take a while to happen. I agree visible effects by 2000 are not strictly implied by the quote, but it's a bit strained to say it's not suggested. Carbon stays in the atmosphere for a long time, but, unless I'm mistaken, the earth thermalizes to the temperature associated with a steady carbon level (inducing a corresponding sea level rise) fairly quickly. (Original commenter said 2000s.) My understanding is that most of the worrying "inertia" for warming, where the damage appear later, comes from either more complicated climate mechanisms (beyond just sea level rise from melting ice) and the slowness of changing the energy sector.
- Gravityloss 9y ago
  This was about sea level rise. Glacier melting takes decades. There are potential very nonlinear effects with that too, so at some point, much later, sea level rise can be very fast, and it's too late to do much by then anymore. This is a very rough sketch and going by memory so best to check for yourself: on Antarctica, there are certain "gatekeeper" glaciers in valleys between the sea and large lowlands with multikilometer thick ice. If the gatekeeper glacier is lost, then the sea will flow into the big basin, and the large area will melt rapidly / float away as ice bergs etc. Eric Rignot has some interesting presentations: https://www.youtube.com/watch?v=u3ivlofypzE https://www.youtube.com/watch?v=u3ivlofypzE
  - jessriedel 9y ago
    Thanks!

jessriedel 9y ago

> But at least from your quote, the actual effects are not supposed to happen by the year 2000. > It's just that the amount of CO2 emitted by year 2000 has already committed us to a certain amount of climate change, that will just take a while to happen. I agree visible effects by 2000 are not strictly implied by the quote, but it's a bit strained to say it's not suggested. Carbon stays in the atmosphere for a long time, but, unless I'm mistaken, the earth thermalizes to the temperature associated with a steady carbon level (inducing a corresponding sea level rise) fairly quickly. (Original commenter said 2000s.) My understanding is that most of the worrying "inertia" for warming, where the damage appear later, comes from either more complicated climate mechanisms (beyond just sea level rise from melting ice) and the slowness of changing the energy sector.

Gravityloss 9y ago
This was about sea level rise. Glacier melting takes decades. There are potential very nonlinear effects with that too, so at some point, much later, sea level rise can be very fast, and it's too late to do much by then anymore. This is a very rough sketch and going by memory so best to check for yourself: on Antarctica, there are certain "gatekeeper" glaciers in valleys between the sea and large lowlands with multikilometer thick ice. If the gatekeeper glacier is lost, then the sea will flow into the big basin, and the large area will melt rapidly / float away as ice bergs etc. Eric Rignot has some interesting presentations: https://www.youtube.com/watch?v=u3ivlofypzE https://www.youtube.com/watch?v=u3ivlofypzE
- jessriedel 9y ago
  Thanks!