So its like most aspects of human caused global warming theory then?

My question on albedo wasn’t only referring to albedo over the Arctic, I was meaning global. I often hear references to global warming increasing the water vapour in the air, this vid mentioned decreased albedo from the Arctic, I was wondering if this would be more than offset from any increased albedo from evaporation, .

Second, Gareth you mention the hole in the ozone layer over Antarctica. There is also a hole over the northern pole. Why would one hole create cooling and the other not?

There is an ozone hole over the Arctic during boreal spring, but it is much more diffuse than that over Antarctica (people were surprised when it was first discovered — it was not expected). The polar vortex — the round-the-pole circulation in the atmosphere — is not so “tight” up North, and so the hole is not so focussed. Geography also plays a part. Antarctica is a cold, high plateau surrounded by a cold, circumpolar ocean current. This creates an intense vortex that tends to “trap” air at the pole, allowing it to cool more than in the Arctic, which is pretty much the reverse of the Antarctic — an ocean surrounded by relatively low lands.

An intensification of the polar vortex in the southern hemisphere has been observed for some time, and is having an impact on the distribution of sea ice (see my link above), and via the Southern Annular Mode/ENSO /PDO interactions, likely on NZ weather patterns as well (subject of active study).

Hope that helps. If any of the Jims are reading, you might chip in too

First this is discussion. These are questions. I’m not an expert on these matters and don’t claim to be. But when I read/watch things like this I can’t help but question some of the logic

On albedo loss. He mentions increased evaporation and atmospheric water vapour. Would the loss of albedo from sea ice melt not be out-weighted by the increase in albedo from increased cloudiness?

Second, Gareth you mention the hole in the ozone layer over Antarctica. There is also a hole over the northern pole. Why would one hole create cooling and the other not?

Reporting in the journal Geophysical Research Letters, scientists from British Antarctic Survey (BAS) and NASA say that while there has been a dramatic loss of Arctic sea ice, Antarctic sea ice has increased by a small amount as a result of the ozone hole delaying the impact of greenhouse gas increases on the climate of the continent.

Meanwhile, Greenland and Antarctica continue to lose large amounts of ice – thinning dramatically at the edges.

Tedesco M., and A. J. Monaghan, 2009. An updated Antarctic melt record through 2009 and its linkages to high-latitude and tropical climate variability. Geophysical Research Letters, 36, L18502, doi:10.1029/2009GL039186.

It’s not a simple vol vs area issue based on thermal mass and amount of water stored, as there’s the Al Bedo guy mixing things up as well eh? Probably also hydrodynamic effects on ocean flows?

I think I’ll stand by my original point about the risks of apparently naive scientists making probably true but easily misconstrued statements of fact (especially if one is wanting to ‘re-purpose’ the findings).