Dear Bazz,

Do your own research as I suggested earlier,
if you're really interested in the topic.
Otherwise you're simply stirring - and I'm not
going to bite.

Bazz: OK Cossomby, so I am ignorant, then enlighten me as to why the ice does not melt at temperatures only 5c below current temperatures?

OK, Bazz: Because temperature over the higher altitudes of the Northern Hemisphere wasn't 'only 5 degrees below current temperatures'. The 5 degree drop was the average for the world, tropics included, high latitude/altitude places would have experienced steeper drops, and/or seasonal differences eg if the summers were relatively colder then winter snow would not melt and over time would build up into glaciers and ice sheets which because of their thickness would be more resistant to melting even in a warmer summer.

So much water was tied up as ice, there was less to rain in warmer places eg tropical and temperate regions; less cloudy weather meant colder weather in winter even in lower latitudes/altitudes, resulting in a feedback process. The circumpolar current around Antarctica kept the southern hemisphere (away from Antarctica) warmer but it was also much drier (because of less rain) so glaciers were limited to Tassie and the Alps: the lack of rain counterbalanced towards colder conditions inland; desert dunes were active over much of southern Australia and even in the drier east of Tasmania. This resulted in the apparent paradox that at the height of the ice age the inland lakes of Australia were fullest - because although there was less rain, the colder weather meant less evaporation, and there was more run-off from snowmelt at lower altitudes below the permanent glaciers.

That is a very brief summary leaving out a lot of factors: changes in atmospheric circulation and the increase of land area as the sea level rose.

It is very complicated; so difficult to give a simple answer to your question. There are innumerable books and papers available on the subject from the last 150 or so years.

Congratulations Cossomby,

Someone who actually knows what they're talking about.
Makes a very refreshing change. Welcome.

Thanks also to Foxy for the worthwhile explanatory information.

Strange about 'ozdoc' - peeks in, seemingly to offer some 'informed' comment, and immediately racks-off (or is it wrack-off) with barely a 'peep'. A bit unusual, wouldn't you say?

Anyway, keep up the good work.
(PS. I have to wonder if the IPCC, and 'climate science' generally, is/are going about tackling this issue the right way. Somehow I can't see how microscopic examination of current 'minutiae', crunching all possible variables, can provide us with the necessary answers.
I would have greater hope in the detailed study of the historical record - ice cores, paleo-sediments and such - in quest of answers.)

Thanks Cossomby, I can understand the explanation you have given
except it does not fit too well with Foxy's original statement.

I have not seen maps showing the ice age coverage of Nth America but I
have seen maps showing the ice age coverage of Europe right down to the Mediterranean.
If there was similar coverage in NA, then the ice age would have to be
melting if temperatures were only 5 deg lower than current temperatures.
Presumably it would take a long time to melt it all but
I just cannot see that the ice thickness could be maintained.

The only other explanation I can see is that the summer to winter
differential would have to be very much larger than it is now.

Anyway I think we have worn it out.

My thoughts will not find much of a welcome here.
But this mornings news papers are full of Abbott,s actions in this area.
Yes he was elected with a mandate.
In my view he has the right to rule as he wishes.
I am aware we can question what that mandate is.
Even with some truth claim his only real mandate was to replace Rudd.
But would we on my side support such a view if it was us in office.
I read then re read the story of his actions yesterday.
See in truth I am not yet able to watch the bloke talk, I run to the TV and change channel.
Find my self content to hide behind play school, even watch it!
Until he is silent.
Coming back to the channel after he is gone I cringe and force myself to watch him on the news.
So why do I find myself breaking in to a chuckle?
Acts like this, he has every right to do it, are leaving him and my country exposed, just as true action is taking place we are heading back in to the dark ages.
So? go Tony you good thing! best campaigner for my side in years.
There my ALP friends is our joy Tony is reminding voters of what we lost.

A very interesting article by the world renowned scientist David Suzuki in yesterdays SMH warning Abbott that he ditches the carbon tax at our nation's peril.

http://www.smh.com.au/comment/tony-abbott-will-doom-future-generations-if-he-ditches-carbon-tax-20130917-2tx0j.html

Abbott and his cronies in politics and business are driven by the short sighted profit motive and show no regard for the future of the planet. They see action on climate change as a cost to be avoided, an impairment to profits. Abbott and his so called fellow skeptics simply deny the reality of climate change at their peril. Unfortunately these skeptics with their money and power may realise the folly of their ways when its too late to save future generations.