May Had Fourth Coldest Globar Temperatures - Page 4

metreon · 06-20-08, 05:47 PM

If for the moment, one discounts the debatable quality of the arctic ice data before 1950, in order for you to associate the prior melting event with the current one based on the theory you are citing, you would have to propose a mechanism for a 100 year weather cycle and then explain why it is far more extensive today than in 1900. It still doesn't add up, but is definitely more plausible than simply sitting it atop contradictory temperature data.

Moreover, my understanding is that there has been a fairly steady loss of sea ice for 30 years, that tends to suggest the wind data might just be secondary to the actual cause of the loss of ice. In other words, the thinner blocks of spring and summer ice have less mass therefore get pushed around more by existing wind patterns. The wind then amplifies the melting effect but doesn't cause it. Just as higher sea temperatures may be secondary to the loss of the ice cover but are not causal. That would suggest multiple feedback loops are acting in this situation and support the idea of a flip-flop state arctic ice, in otherwords, you have it or you don't.

Given ice data prior to 1950 is pretty debatable and spotty anyway, I would have to still say the historic sea ice melt info was irrelevant to the original question, despite your protest. For example, Viking history suggest a clear period during the colonization of Greenland in the middle ages, but I probably wouldn't draw any definitive conclusions about that regarding today's warming since they can't be compared on a quantitative basis.

Nevertheless, it's still an interesting issue in flux. Given that the lower recent air temps you cited resulted in a restoration of the extent of arctic ice this winter, but not the thickness, it will be interesting to see how the ice breaks up later this summer. So what direction are the winds blowing this year? It will be interesting to see if it matters or not.

(The alternate dataset referred to was to the earlier poster, middleground, who posted similar data spanning a wider time frame than your original post.)

jfuh · 06-20-08, 08:33 PM

Quote:

Originally Posted by metreon

If for the moment, one discounts the debatable quality of the arctic ice data before 1950, in order for you to associate the prior melting event with the current one based on the theory you are citing, you would have to propose a mechanism for a 100 year weather cycle and then explain why it is far more extensive today than in 1900. It still doesn't add up, but is definitely more plausible than simply sitting it atop contradictory temperature data.

Moreover, my understanding is that there has been a fairly steady loss of sea ice for 30 years, that tends to suggest the wind data might just be secondary to the actual cause of the loss of ice. In other words, the thinner blocks of spring and summer ice have less mass therefore get pushed around more by existing wind patterns. The wind then amplifies the melting effect but doesn't cause it. Just as higher sea temperatures may be secondary to the loss of the ice cover but are not causal. That would suggest multiple feedback loops are acting in this situation and support the idea of a flip-flop state arctic ice, in otherwords, you have it or you don't.

Given ice data prior to 1950 is pretty debatable and spotty anyway, I would have to still say the historic sea ice melt info was irrelevant to the original question, despite your protest. For example, Viking history suggest a clear period during the colonization of Greenland in the middle ages, but I probably wouldn't draw any definitive conclusions about that regarding today's warming since they can't be compared on a quantitative basis.

Nevertheless, it's still an interesting issue in flux. Given that the lower recent air temps you cited resulted in a restoration of the extent of arctic ice this winter, but not the thickness, it will be interesting to see how the ice breaks up later this summer. So what direction are the winds blowing this year? It will be interesting to see if it matters or not.

(The alternate dataset referred to was to the earlier poster, middleground, who posted similar data spanning a wider time frame than your original post.)

Couldn't have said it any better.

Gill · 06-23-08, 07:29 AM

Quote:

Originally Posted by metreon

If for the moment, one discounts the debatable quality of the arctic ice data before 1950, in order for you to associate the prior melting event with the current one based on the theory you are citing, you would have to propose a mechanism for a 100 year weather cycle and then explain why it is far more extensive today than in 1900. It still doesn't add up, but is definitely more plausible than simply sitting it atop contradictory temperature data.

More extensive today than in 1900?? You base this assumption on what? You act as if I proposed some crackpot theory on why ice is breaking up in the Arctic. You seem to forget that this is the findings by NASA scientists as recently presented in a peer reviewed publication.

Quote:

Moreover, my understanding is that there has been a fairly steady loss of sea ice for 30 years, that tends to suggest the wind data might just be secondary to the actual cause of the loss of ice. In other words, the thinner blocks of spring and summer ice have less mass therefore get pushed around more by existing wind patterns. The wind then amplifies the melting effect but doesn't cause it. Just as higher sea temperatures may be secondary to the loss of the ice cover but are not causal. That would suggest multiple feedback loops are acting in this situation and support the idea of a flip-flop state arctic ice, in otherwords, you have it or you don't.

Maybe you know more that NASA climate specialists... Try reading the paper and then we can discuss it.

Quote:

Given ice data prior to 1950 is pretty debatable and spotty anyway, I would have to still say the historic sea ice melt info was irrelevant to the original question, despite your protest. For example, Viking history suggest a clear period during the colonization of Greenland in the middle ages, but I probably wouldn't draw any definitive conclusions about that regarding today's warming since they can't be compared on a quantitative basis.

Why would you think ice data prior to 1950 is "debatable" or "spotty"?? While I admit that satellites did not measure ice to the millimeter as is done now; however, pretty accurate ice data is available for hundreds of years into the past. There are several papers that detail historical ice coverage.

Quote:

Nevertheless, it's still an interesting issue in flux. Given that the lower recent air temps you cited resulted in a restoration of the extent of arctic ice this winter, but not the thickness, it will be interesting to see how the ice breaks up later this summer. So what direction are the winds blowing this year? It will be interesting to see if it matters or not.

The alternate dataset referred to was to the earlier poster, middleground, who posted similar data spanning a wider time frame than your original post.)

Ice can take years to rebuild thickness. I won't be surprised at all if the ice breaks up extensively this year. How do you explain the record ice extent in the Antarctic??

The graph posted by Middleground started the exact year that global atmospheric warming began. Of course it will have an upward trend slope.

I see that middleground is still lurking in this thread, but hasn't botherred to post anything that "tears me to shreds" yet.

Gill · 06-23-08, 07:30 AM

Quote:

Originally Posted by jfuh

Couldn't have said it any better.

You're right for once... you couldn't have said it better.