Am I still allowed to question climate change?

[El Cid]

Rubbish. .

 

So its not a noun?

Edited February 8, 2017 by El Cid

[Robin-H]

This is true. But most of the public discussion is over the polar ice, which is irrelevant to sea levels.

 

The discussion is about the polar ice because it is a more obvious side effect of the warming.

 

We can see the satellite images that show just how much the summer melting of the arctic ice cap has increased in recent years, whereas as the melting from the Greenland is reducing the ice in depth, and not area, it is less visible.

 

It is a clear example of the damaging effect of climate change, one of the consequences of which is sea level rise, so although the melting polar ice might not contribute directly to the sea level rise it is a powerful and easily understood visual. I feel that is why the discussion is over polar ice.

[unbeliever]

The discussion is about the polar ice because it is a more obvious side effect of the warming.

 

We can see the satellite images that show just how much the summer melting of the arctic ice cap is increased in recent years, whereas as the melting from the Greenland is reducing the ice in depth, and not area, it is less visible.

 

It is a clear example of the damaging effect of climate change, one of the consequences of which is sea level rise, so although the melting polar ice might not contribute directly to the sea level rise it is a powerful and easily understood visual. I feel that is why the discussion is over polar ice.

 

You're probably right, but it's extremely misleading.

[sgtkate]

No it's a perfectly reasonable question.

Ice has lower density than water, so the part you see sticking out is about 10% of the total and the remaining 90% under-water takes up as much space as the melted version.

 

I know, but 10% of the ice caps of additional water in the sea is surely quite a large amount? We'd have to know the volume of the entire icecaps versus sea level to be able to plot the impact though. I'm sure that's been done as it's pretty obvious but a Google search has eluded me. And clearly not all the ice caps are melting...yet.

[unbeliever]

I know, but 10% of the ice caps of additional water in the sea is surely quite a large amount? We'd have to know the volume of the entire icecaps versus sea level to be able to plot the impact though. I'm sure that's been done as it's pretty obvious but a Google search has eluded me. And clearly not all the ice caps are melting...yet.

 

As the ice melts it shrinks. The 2 effects cancel out.

[Robin-H]

You're probably right, but it's extremely misleading.

 

Why is it extremely misleading? Climate change is resulting is melting polar ice and it is also resulting in sea level rises from the melting of the polar caps on Greenland and Antarctica as well as thermal expansion.

 

It would be misleading if the sea level rises weren't a consequence of climate change but were being presented as one, but it is a consequence.

[unbeliever]

Why is it extremely misleading? Climate change is resulting is melting polar ice and it is also resulting in sea level rises from the melting of the polar caps on Greenland and Antarctica as well as thermal expansion.

 

It would be misleading if the sea level rises weren't a consequence of climate change but were being presented as one, but it is a consequence.

 

It leaves people with the impression that melting sea ice causes sea level rises.

[sgtkate]

As the ice melts it shrinks. The 2 effects cancel out.

 

Found this article that appears fairly neutral although I don't fully understand some of the science (just read the opening paragraph so I withdraw my comment about it being neutral, however, I'm fairly certain the numbers quoted are correct as they could be fairly easily disproved by someone who is better at maths than me!):

 

http://www.johnstonsarchive.net/environment/waterworld.html

 

From that link:

Using the ice volume figures from above it is straightforward to estimate the effect on sea level were all this ice melted. Melting the 29,300,000 km3 of grounded ice would produce 26,100,000 km3 of water. Note that melting of floating ice has no effect on sea level. Also, about 2,100,000 km3 of the grounded ice in Antarctica is below sea level [19] and would be replaced by water. Thus, the net addition to the world's oceans would be about 24,000,000 km3 of water spread over the 361,000,000 km2 area of the world's oceans, giving a depth of 67 meters. The new ocean area would be slightly larger, of course, since some areas now land would be covered with water. The final result would be around 66 meters (current estimates range between 63 and 75 meters).

 

 

So grounded ice melting alone would cause 67m sea level rise if it all melted. Clearly that's not going to happen anytime soon but at least we now seem to be getting some provable figures.

Edited February 8, 2017 by sgtkate

[unbeliever]

Found this article that appears fairly neutral although I don't fully understand some of the science:

 

http://www.johnstonsarchive.net/environment/waterworld.html

 

From that link:

Using the ice volume figures from above it is straightforward to estimate the effect on sea level were all this ice melted. Melting the 29,300,000 km3 of grounded ice would produce 26,100,000 km3 of water. Note that melting of floating ice has no effect on sea level. Also, about 2,100,000 km3 of the grounded ice in Antarctica is below sea level [19] and would be replaced by water. Thus, the net addition to the world's oceans would be about 24,000,000 km3 of water spread over the 361,000,000 km2 area of the world's oceans, giving a depth of 67 meters. The new ocean area would be slightly larger, of course, since some areas now land would be covered with water. The final result would be around 66 meters (current estimates range between 63 and 75 meters).

 

 

So grounded ice melting alone would cause 67m sea level rise if it all melted. Clearly that's not going to happen anytime soon but at least we now seem to be getting some provable figures.

 

 

That seems right to me.

 

But there's another effect in play:

Water occupies the least volume at 4ºC. Cooler, or hotter than that and it expands. Water has enormous thermal capacity, so it takes decades or more likely centuries for extra average surface temperatures to filter down to the deep water.

Any sea level rise from thermal expansion has little or nothing to do with modern human activity.

[Robin-H]

That seems right to me.

 

But there's another effect in play:

Water occupies the least volume at 4ºC. Cooler, or hotter than that and it expands. Water has enormous thermal capacity, so it takes decades or more likely centuries for extra average surface temperatures to filter down to the deep water.

Any sea level rise from thermal expansion has little or nothing to do with modern human activity.

 

Have you got any evidence I can read for that claim?