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OT: Moorabal/Lal Lal wind farm 10-Jun-2009 At 8:39:13 AM wombly

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This thread is actually quite funny. It's a microcosm of the debate that has happened in
the scientific community - only it happened there about 25 years ago and most boffins
have long since moved on to trying to figure out how to live with climate change given
that the broader community doesn't seem to want to stop it. But I'll take up the troll and
wade into it anyway.

>But if you think, that due to the fact that the evidence is not sound because it's
>geospecific, we could also ignore the recent decrease in Arctic ice (it's only covers
>10% anyway) and focus on the overall global glacial trend. Some have shrunk, some
>have expanded and some have stayed the same. Overall the volume is the same as
>before this scare campaign started

There's a host of problems with this statement particlualry comparing sea ice with
glaciers, as changes in these are driven by different factors. But the real clanger is that
idea that the overall global ice volume is remaining steady. this is a serious furphy, and
shows a distinct lack of understanding of just what is actually happening around the
world and also what causes changes the mass of a glacier (it's a balance of ice in -
accumulation from snowfall - and ice out - surface melt, iceberg calving etc).

Most of the small, alpine glaciers around the world are shrinking dramatically. The alps,
himalaya, african high mountains, northern andes, the rockies to name but a few. These
guys recieve small amounts of snowfall each hear and are thus quite sensitive to
changes in temperature.

There are a few glaciers in the sub-arcitic lattitudes that are undergoing expansion. e.g.
the fox and tasman on the west coast of NZ, and a few in patagonia and some in
maritime alaska. These glaciers are in relatively warm areas, but are there because they
are fed by huge amounts of snowfall where the westerly trade winds are forced up over
mountain ranges. Hence, they are more sensitive to changes in accumulation. so their
advance is acutally further evidence for an overall warming of the climate, as a warmer
world means more rapid atmospheric circluation, which means more rain/snowfall in
these areas.

Polar ice si a bit more complicated, but also points to an overall trend of ice loss in
most areas. In areas where sea ice is being lost, such as around the antarctic
peninsula, the dramatic increase in warming due to a loss of albedo has vastly
overwhelmed the small increase in accumulation and ice loss there is scarily fast. Much
faster than the glacier modelling community (including those involved in the coming up
with the IPCC predictions - errors there go both ways) had predicted. In the areas just
toward the poles the change is less obvious - temperatures have increased but it's been
offset by an increase in precipitation as their moisture sources are now much closer
(you don't get much evaporation from a frozen sea). So again, the response is
consistent with the notion of a 'global warming'.