Reading this excellent post, what occurred to me as I read about 1 mm/yr sea level increase is how pitifully small that sounds to people who can't comprehend how huge the world is and what a great big honking huge change we're talking about.

To do ANYTHING that changes the entire world by even a little bit is to do something enormous.

What popped into my head when I read the post was a very sharp sense memory of traveling on open ocean for days and days and seeing NOTHING but sea.  Travelling without jets gives you an indelible sense of how vast is the world, which is what enables you to appreciate just how serious something is, even if it sounds tiny, if it's a worldwide effect.

I don't think most people who travel by jet have a good sense of this.  I wish everyone currently flying around would take the Empire Builder or Southwest Chief a few times, so they really come to appreciate how big the American west is; and that they would take a ship across the ocean rather than fly, so they could really grasp, at a gut level, how extraordinarily enormous anything must be to cause even the tiniest measurable change in sea level.

It's a paradox of human psychology--you'd think that if the world seemed small that we'd realize better that we need to take care of our "global village."  But that doesn't seem to be the way of it--instead, jet travel seems to create a kind of amnesia that convinces those who do it that there's nothing that man can't do with his machines; something about roaring around at 400 knots makes the world very small and, at the same time, seemingly too big to be affected by what humans do.  But it is affected by what humans do, very much so.  I think we need people to spend a lot more time moving through the world more slowly in order to appreciate the magnitude of what we're doing.

Save the world: Reduce greenhouse gas emissions 5% annually.

JMG is like what you wrote and Joseph did a bang-up job on such a complex subject made so simple - it is really a 1-2-3 punch.  

It was synchronous because I wanted to blog about how glacial and arctic sea ice melt could COOL the oceans in certain places.  

But where does the meltwater go?  Freshwater would float on top, since its density of 1000 kg/m3 is lighter than saltwater at 1020-1030 kg/m3.  

However, ice can be formed from saltwater and in this case it would probably sink.  It's a fascinating science because the pancake floes and ice shelf is actually a mixture of freshwater, saltwater, and any detritus trapped in the stuff.  

Bear with me, but an article called "Climate History Rewritten: Arctic Ice" (2006 abstracts, no author cited) over at Brown University says the artic ice shield is about 45 million years old and the study findings make some very important conclusions about the role of CO2 in global warming.

In terms the geologic history of the Earth, the artic ocean froze in a mere moment.  It could melt just as fast, although maybe a litle longer because of some latent heat issues.  

I agree it is scary, and definitely non-linear.
/sammie

Onward through the fog

Quoting Hansen: "Important decisions are being made now and in the near future. An example is the large number of new efforts to make liquid fuels from coal, and a resurgence of plans for energy-intensive `cooking' of tar-shale mountains to squeeze out liquid hydrocarbon fuels. These are just the sort of actions needed to preserve a BAU greenhouse gas path indefinitely. "

Hansen's predictions that we could control global warming by stopping coal use, even with oil use, are predicated on these policies not happening, but Obama came out for coal-to-liquids and the phrase "Canadian tar sands" is thrown around like the businessman who whispered "Plastics" to Dustin Hoffmann in the movie "The Graduate".