6 ms·

Clearest indication yet that polar ice sheets are melting fast

42 points by jfoucher 14y ago

meric 14y ago
Also permafrost is melting (irreversibly on human time-scales): http://www.smh.com.au/environment/climate-change/where-even-the-earth-is-melting-20121127-2a5tp.html http://www.smh.com.au/environment/climate-change/where-even-...
- pyre 14y ago
  > (irreversibly on human time-scales) This comes across as ambiguous and I didn't understand what you meant until I read the article. "It's happening at a rate that is irreversible on human time-scales"
  - rdtsc 14y ago
    I don't know what the original poster meant but I understand it to be that if it is cyclic phenomena and/or was/can be triggered by human activity, it has already entered into a phase that make it unlikely to be reversed no matter what humans do in say one to tens of humans lifetimes (say 100 to 1000 years). The system might correct itself or cycle back but it would be on very large time scales. The main gist from the articles is that the perma frost echo system is an amplifier for climate change. So it is like positive feedback. For maybe for what seems like a small change contributed by human activity, the permafrost echo system might respond and amplify that by some large factor. Anyway I don't know enough about the issue but that is what I understood from the article.
    - pyre 14y ago
      Maybe I wasn't even as clear as I intended, but I read it as: Now that this change has happened, 'putting the genie back in the bottle' would take an enormous amount of time. Even if there was a dedicated, directed effort to do so, we would probably be talking time-scales of millennia rather than things that us humans would actually be able to look forward to (even a couple of generations forward).
deleted 14y ago
[deleted]
- nitrogen 14y ago
  The land underneath, the hard bits underneath your chair is floating on molten metal. And the water in the ocean is floating on top of this hard substance that is floating on molten metal. The surface of the earth is in Constant change, half rising, half falling at varying rates. It's a good thing, then, that there are satellites measuring the earth's gravity, temperature, and land/sea level on a global basis, not just at coastlines. Also, the position of ground-based sensors would be tracked by GPS, so one could tell if the land itself was rising or falling. As a layperson I've learned that lot of effort goes into developing consistent, scientifically useful models of the earth's shape and position: https://en.wikipedia.org/wiki/Geodesy https://en.wikipedia.org/wiki/Geodesy The amount of science in "Climate change and ocean rising/falling discussions" makes me want to gouge my eyes out, usually they are about as scientific as pyramid power. Did you read the linked article? Granted, a lot of popularized articles about climate change contain propagandizing and pounding of phrases like "settled science," and I don't know why that is, but that doesn't invalidate the science that actually exists. Reading a large number of climate change articles on e.g. Ars Technica leaves me with a pretty good impression of the state of actual climate science, certainly better than my impression of "pyramid power." Edit: since the comment to which I replied was deleted I will not post the username of its author, but here is the original text: Plate tectonics cause land to rise/fall faster than the speed at which the ocean is rising/falling. Tides are affected by many factors like ocean currents, weather patterns, temperatures, changes in the very shape of the Earth itself. The land underneath, the hard bits underneath your chair is floating on molten metal. And the water in the ocean is floating on top of this hard substance that is floating on molten metal. The surface of the earth is in Constant change, half rising, half falling at varying rates. If the frothing bubbling iron soup under the land were to change at all due to gravimetric or other physical reasons, the changes in sea level would be far more dramatic than what is measured in the sea level change. You can't just go to your local beach and stick a measuring pole in the sand with a calendar and a clock. Likewise you can't just go to a thousand randomly selected beaches and run averages, why? Because you are only testing the ocean's edges, you need to randomly test the depth of the ocean at every point. To do this right, you must actually calculate the volume of Ocean water, and this hurts people's brains because it is impossible and isn't good for FUD articles. It could very well be possible that the oceans would normally be receding on account of other factors, yet it is still rising from the perspective of beaches because the Earth is becoming more spherical. The amount of science in "Climate change and ocean rising/falling discussions" makes me want to gouge my eyes out, usually they are about as scientific as pyramid power. I choose to ignore people who talk about these sorts of things because I like to learn things by proofs, not be taught to believe things because of propaganda and agenda driven fear uncertainty and doubt for the profit of unscrupulous manipulators.
genuine 14y ago
What good does this do? Should I go into bankruptcy insulating my house with aerogel to protect against severe climate change? If the weather gets hot or there is a drought, environmentalist scientists tell the media that problem is global warming caused by humans. If the weather gets colder, environmentalist scientists tell the media that problem is climate change caused by humans. If it gets really damn cold outside, or really damn hot, then we need to make good insulation cheaper. Whining about it doesn't do a damn bit of good.
- nitrogen 14y ago
  If the weather gets hot or there is a drought, environmentalist scientists tell the media that problem is global warming caused by humans. If the weather gets colder, environmentalist scientists tell the media that problem is climate change caused by humans. That's not what I've been hearing. I see people saying that no individual weather event or localized change can be attributed to global climate change, but that as more total energy is added to the earth system, more chaotic weather events and localized changes can be expected in aggregate (edit: e.g. http://youtu.be/5EaLVOv8cIk?t=1m49s http://youtu.be/5EaLVOv8cIk?t=1m49s).
- lifeformed 14y ago
  Well, it's good to have details on the causes and effects of these kinds of problems, so we can better decide how to prevent it from happening more. Our efforts shouldn't be purely reactive, it should also be preventative.
deleted 14y ago
[deleted]
sighagain 14y ago
This is what is laughable. The original IPCC report on global warming predicted an average rate of global mean sea level rise of about 6 cm per decade. The reality? 11 mm or less over the last 2 decades! That's over a factor of 100 miss. Nobody seems to notice how the goal posts on this issue are constantly moving. In the end, yes, there is global warming, but it is not even close to what was predicted in the late 1980s and early 1990s. http://en.wikipedia.org/wiki/IPCC_First_Assessment_Report http://en.wikipedia.org/wiki/IPCC_First_Assessment_Report
- nitrogen 14y ago
  Science is science because it is allowed to change its mind when presented with new data.
  - PakG1 14y ago
    The unfortunate thing happens when incomplete science is used for political posturing and policy.
    - ThisIBereave 14y ago
      There certainly does seem to be a lot of political posturing going on, but I don't think it is coming from the scientists.
      - PakG1 14y ago
        Although I never said that it was, I would at the same time caution against making broad sweeping statements.
  - CamperBob2 14y ago
    Economics is a bit different. When you make economic decisions based on questionable data, people suffer.
    - eru 14y ago

42 points by jfoucher 14y ago

meric 14y ago

Also permafrost is melting (irreversibly on human time-scales): http://www.smh.com.au/environment/climate-change/where-even-the-earth-is-melting-20121127-2a5tp.html http://www.smh.com.au/environment/climate-change/where-even-...

pyre 14y ago
> (irreversibly on human time-scales) This comes across as ambiguous and I didn't understand what you meant until I read the article. "It's happening at a rate that is irreversible on human time-scales"
- rdtsc 14y ago
  I don't know what the original poster meant but I understand it to be that if it is cyclic phenomena and/or was/can be triggered by human activity, it has already entered into a phase that make it unlikely to be reversed no matter what humans do in say one to tens of humans lifetimes (say 100 to 1000 years). The system might correct itself or cycle back but it would be on very large time scales. The main gist from the articles is that the perma frost echo system is an amplifier for climate change. So it is like positive feedback. For maybe for what seems like a small change contributed by human activity, the permafrost echo system might respond and amplify that by some large factor. Anyway I don't know enough about the issue but that is what I understood from the article.
  - pyre 14y ago
    Maybe I wasn't even as clear as I intended, but I read it as: Now that this change has happened, 'putting the genie back in the bottle' would take an enormous amount of time. Even if there was a dedicated, directed effort to do so, we would probably be talking time-scales of millennia rather than things that us humans would actually be able to look forward to (even a couple of generations forward).

deleted 14y ago

[deleted]

nitrogen 14y ago
The land underneath, the hard bits underneath your chair is floating on molten metal. And the water in the ocean is floating on top of this hard substance that is floating on molten metal. The surface of the earth is in Constant change, half rising, half falling at varying rates. It's a good thing, then, that there are satellites measuring the earth's gravity, temperature, and land/sea level on a global basis, not just at coastlines. Also, the position of ground-based sensors would be tracked by GPS, so one could tell if the land itself was rising or falling. As a layperson I've learned that lot of effort goes into developing consistent, scientifically useful models of the earth's shape and position: https://en.wikipedia.org/wiki/Geodesy https://en.wikipedia.org/wiki/Geodesy The amount of science in "Climate change and ocean rising/falling discussions" makes me want to gouge my eyes out, usually they are about as scientific as pyramid power. Did you read the linked article? Granted, a lot of popularized articles about climate change contain propagandizing and pounding of phrases like "settled science," and I don't know why that is, but that doesn't invalidate the science that actually exists. Reading a large number of climate change articles on e.g. Ars Technica leaves me with a pretty good impression of the state of actual climate science, certainly better than my impression of "pyramid power." Edit: since the comment to which I replied was deleted I will not post the username of its author, but here is the original text: Plate tectonics cause land to rise/fall faster than the speed at which the ocean is rising/falling. Tides are affected by many factors like ocean currents, weather patterns, temperatures, changes in the very shape of the Earth itself. The land underneath, the hard bits underneath your chair is floating on molten metal. And the water in the ocean is floating on top of this hard substance that is floating on molten metal. The surface of the earth is in Constant change, half rising, half falling at varying rates. If the frothing bubbling iron soup under the land were to change at all due to gravimetric or other physical reasons, the changes in sea level would be far more dramatic than what is measured in the sea level change. You can't just go to your local beach and stick a measuring pole in the sand with a calendar and a clock. Likewise you can't just go to a thousand randomly selected beaches and run averages, why? Because you are only testing the ocean's edges, you need to randomly test the depth of the ocean at every point. To do this right, you must actually calculate the volume of Ocean water, and this hurts people's brains because it is impossible and isn't good for FUD articles. It could very well be possible that the oceans would normally be receding on account of other factors, yet it is still rising from the perspective of beaches because the Earth is becoming more spherical. The amount of science in "Climate change and ocean rising/falling discussions" makes me want to gouge my eyes out, usually they are about as scientific as pyramid power. I choose to ignore people who talk about these sorts of things because I like to learn things by proofs, not be taught to believe things because of propaganda and agenda driven fear uncertainty and doubt for the profit of unscrupulous manipulators.

genuine 14y ago

What good does this do? Should I go into bankruptcy insulating my house with aerogel to protect against severe climate change? If the weather gets hot or there is a drought, environmentalist scientists tell the media that problem is global warming caused by humans. If the weather gets colder, environmentalist scientists tell the media that problem is climate change caused by humans. If it gets really damn cold outside, or really damn hot, then we need to make good insulation cheaper. Whining about it doesn't do a damn bit of good.

nitrogen 14y ago
If the weather gets hot or there is a drought, environmentalist scientists tell the media that problem is global warming caused by humans. If the weather gets colder, environmentalist scientists tell the media that problem is climate change caused by humans. That's not what I've been hearing. I see people saying that no individual weather event or localized change can be attributed to global climate change, but that as more total energy is added to the earth system, more chaotic weather events and localized changes can be expected in aggregate (edit: e.g. http://youtu.be/5EaLVOv8cIk?t=1m49s http://youtu.be/5EaLVOv8cIk?t=1m49s).
lifeformed 14y ago
Well, it's good to have details on the causes and effects of these kinds of problems, so we can better decide how to prevent it from happening more. Our efforts shouldn't be purely reactive, it should also be preventative.

deleted 14y ago

[deleted]

sighagain 14y ago

This is what is laughable. The original IPCC report on global warming predicted an average rate of global mean sea level rise of about 6 cm per decade. The reality? 11 mm or less over the last 2 decades! That's over a factor of 100 miss. Nobody seems to notice how the goal posts on this issue are constantly moving. In the end, yes, there is global warming, but it is not even close to what was predicted in the late 1980s and early 1990s. http://en.wikipedia.org/wiki/IPCC_First_Assessment_Report http://en.wikipedia.org/wiki/IPCC_First_Assessment_Report

nitrogen 14y ago
Science is science because it is allowed to change its mind when presented with new data.
- PakG1 14y ago
  The unfortunate thing happens when incomplete science is used for political posturing and policy.
  - ThisIBereave 14y ago
    There certainly does seem to be a lot of political posturing going on, but I don't think it is coming from the scientists.
    - PakG1 14y ago
      Although I never said that it was, I would at the same time caution against making broad sweeping statements.
- CamperBob2 14y ago
  Economics is a bit different. When you make economic decisions based on questionable data, people suffer.
  - eru 14y ago