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I wonder if this heat dome effect contributed to Venus' eventual fate. My #1 fear is we're just going to get into some runaway cascade of warming and turn into

by npunt 5y ago

I wonder if this heat dome effect contributed to Venus' eventual fate. My #1 fear is we're just going to get into some runaway cascade of warming and turn into something like Venus much faster than we realize.

freeflight 5y ago
It's kind of sad how we are fantasizing about terraforming Mars, while we've been seemingly very effective at venusforming Terra.
- UnFleshedOne 5y ago
  Well, looking at mars, solutions like "keep slamming it with ice comets till the weather improves" are on the table. On earth we'd have all the NIMBYs whining about impact craters spoiling the view or something.
lamontcg 5y ago
The Earth has had 2,000+ ppm CO2 concentrations in the past and hasn't turned into Venus. And more or less we're going to dig up all the dinosaurs and plants that died and turned into oil/carbon and put them back in the atmosphere and return to that if we do nothing. But we have a record of what that looks like and its not Venus. That's also a very silly things to "fear" since to turn into Venus you gotta do things like melt all of Antarctica, Greenland and the Himalayas first which will take a couple hundred years. There's an awful lot of thermal mass in all that ice. Disruption to agriculture and food production though doesn't require turning the Earth into Venus.
- the_third_wave 5y ago
  The planet has been ice-free in past interglacials, e.g. the last interglacial (before the current Holocene) was warmer than the current. Earth becoming like Venus would take far more terraforming than it would take to turn Mars into a new Earth, probably comparable to turning Venus into an Earth-like planet - i.e. it is not going to happen. In "a few thousand years" [1] the temperature will drop precipitously and we'll be heading for the next ice age if the pattern from the last ~2.5 million years holds. In other words, enjoy the warmth while it lasts, it is sure to get very cold again sometime in the future... [1] which can mean anything from "soon" to "100.000 years" depending on who does the talking
  - lamontcg 5y ago
    A carbon level of 1,000-2,000 ppm will prevent that interglacial from happening and will melt Antarctica by that point in time. For the past 1,000,000 years, through many interglacials, the carbon level has never exceeded 300 ppm. If you look at what "should" be happening right now then we should be cooling. The last interglacial ended 10,000 years ago and the fast Milankovich cycle caused by oscillations of the axial tilt is in a cooling (decreasing tilt) trend. If prior ice age cycles held we should be seeing cooling and the formation of continential glaciers in northern Canada. That natural cycle has been decisively broken.

by npunt 5y ago

freeflight 5y ago

It's kind of sad how we are fantasizing about terraforming Mars, while we've been seemingly very effective at venusforming Terra.

UnFleshedOne 5y ago
Well, looking at mars, solutions like "keep slamming it with ice comets till the weather improves" are on the table. On earth we'd have all the NIMBYs whining about impact craters spoiling the view or something.

lamontcg 5y ago

The Earth has had 2,000+ ppm CO2 concentrations in the past and hasn't turned into Venus. And more or less we're going to dig up all the dinosaurs and plants that died and turned into oil/carbon and put them back in the atmosphere and return to that if we do nothing. But we have a record of what that looks like and its not Venus. That's also a very silly things to "fear" since to turn into Venus you gotta do things like melt all of Antarctica, Greenland and the Himalayas first which will take a couple hundred years. There's an awful lot of thermal mass in all that ice. Disruption to agriculture and food production though doesn't require turning the Earth into Venus.

the_third_wave 5y ago
The planet has been ice-free in past interglacials, e.g. the last interglacial (before the current Holocene) was warmer than the current. Earth becoming like Venus would take far more terraforming than it would take to turn Mars into a new Earth, probably comparable to turning Venus into an Earth-like planet - i.e. it is not going to happen. In "a few thousand years" [1] the temperature will drop precipitously and we'll be heading for the next ice age if the pattern from the last ~2.5 million years holds. In other words, enjoy the warmth while it lasts, it is sure to get very cold again sometime in the future... [1] which can mean anything from "soon" to "100.000 years" depending on who does the talking
- lamontcg 5y ago
  A carbon level of 1,000-2,000 ppm will prevent that interglacial from happening and will melt Antarctica by that point in time. For the past 1,000,000 years, through many interglacials, the carbon level has never exceeded 300 ppm. If you look at what "should" be happening right now then we should be cooling. The last interglacial ended 10,000 years ago and the fast Milankovich cycle caused by oscillations of the axial tilt is in a cooling (decreasing tilt) trend. If prior ice age cycles held we should be seeing cooling and the formation of continential glaciers in northern Canada. That natural cycle has been decisively broken.