muso wrote on Nov 4
th, 2013 at 10:37am:
Ajax,
Reflect on this:
http://www.scientificamerican.com/article.cfm?id=ice-free-arctic-in-pliocene-las... Quote:Ice-Free Arctic in Pliocene, Last Time CO2 Levels above 400 PPM
Scientists trying to determine how the Earth might change as temperatures rise often look back in time to a period around 3.6 million years ago called the middle Pliocene, when concentrations of carbon dioxide ranged from about 380 to 450 parts per million. (Today they are nearing 400.)
A study published yesterday in the journal Science analyzed the longest land-based sediment core ever taken in the Arctic and found that during this period, from 3.6 million to 2.2 million years ago, the area around the North Pole was much warmer and wetter than it is now.
In the middle Pliocene, summer temperatures in the Arctic were around 60 degrees Fahrenheit, which is about 14 degrees warmer than they are now, the study found.
The sediment core came from the bottom of a deep lake in Russia about 60 miles north of the Arctic Circle, called Lake El'gygytgyn.
Why isn't it ice free today? Well one of the factors is that it's not at equilibrium.
How can I explain this in simple terms that you will understand?
Ice - He dead man walking. Is it possible to get ice in a cup of boiling water? Yes. It takes a certain finite time to melt. The ice in the hot water has not yet reached equilibrium.
Now, what we know about the early Holocene is that sea levels rose because of certain discrete events. One of the things that happened during the melt was that a huge lake (Lake Agassiz) burst through the ice and raised sea levels very quickly.
The article in the OP is about "Arctic Summer Temperatures", not sea ice.
First of all that was interesting read with interesting findings.
What spoils it is the last sentence where she say that CO2 is causing todays warming.
Her project wasn't about CO2 and its impact today.
So how can she just slip in a comment like that, is she qualified to do so.
She really discredits her self when she has done such great work and then insinuates something else completely unrelated to her work.
Can we have ice in boiling water..???
Yes we can if we are trying to melt a block of ice in a container with a heat source.
Whether the arctic is in equilibrium or not I don't think either side can claim to know 100%.
What is certain though and I think both sides would agree on this is that we are coming out of a mini ice age since about the 1700 to 1800 hundred, I cant remember exactly.
Its only reasonable to expect temperature to rise and sea ice to melt its all part of the natural cycle of the peaks and troughs the Earth experiences.
Add to this our sun being very active over the last century and what we have today is no cause for alarm imo.