When you cannot trust the models then you have to study paleoclimatology. Holocene Thermal Maximum conditions ~8000 years ago had led to summer ice far less than 2m km2 extent(possibly half than this). Temperatures over the arctic are reaching the HTM levels. So 2 sq km will be reachead very soon.

The models should have been totally redisigned when we found out that during the holocene thermal maximum there was little if any ice in the summer in the arctic. HTM was as warm as today. Like Hansen, I prefer to trust the paleoclimatic data than models.

I wouldnt bet on cold fusion, but if I was an american I would demand a second Manhatan project for finding clean energy from fission or fusion. It can be done. But research requires money and effort. ITER, that has a very high propability of getting energy from fusion, will cost 20 billion dollars over 12 years. Compare that to 5 trillion that is the value of fossil fuel that the planet burns every year. My opinion. No cap and trade nonsense. No taxes. Fossil fuels are so cheap and the CEOs have bought the politicians so that there will always be loopholes. Do the simple thing, tax all fossil fuels on the planet with 5%. That 250 billion $ can then be allocated to the UN which can allocate the money to whatever projects the world community believes has the best propability of success. This warranties not any significant impact on lifestyle, but R&D on advanced fission,fussion and solar will skyrocket.

Yeap. Nobody has any idea what the cost will be. Actually if sufficient funds were directed to 1)Liquid Thorium Reactors 2)Breeder Reactors 3)Fusion reactors 4)Wind and Solar then the funny part is that these technologies would be far far cheaper than oil and NG and on parity with Coal. We know how to build bad reactors. We need to learn how to make good reactors (low waste and high safety). And than needs investment.

How is it possible for people to write so ill informed articles on newspapers/magazines? When people say "Its better for human beings, humans thrive in warmer climates". Several points. 1)Modern humans existed during the last interglacial period. They did not manage to create civilization. One possibility is that that the climate was significantly different from todays (and only by just 1 degree higher than 1950s), which did not allow the onset of agriculture. But this is speculation with no hard evidence if any. 2)1 degree higher than 1950s, we will survive it. 2-3 degrees is huge difference. During the pliocene the climatic conditions were very different compared to todays climate. 3) More than 3 degrees will lead not only to very significant alterations to the climate but also the onset of positive feedback loops which means bye bye coastal cities. 4) Six degrees which is not an impossibility will alsmost certainly lead the clathrate guns to fire. Based on paleoclimatic evidence, this will lead to another 6 degrees more heating. Then we will be lucky if Earth does not become like Venus. So the cost is 500 trillion dollars. Well guess what, Mars' banks do not accept Us dollars. You need to use them on Earth. And the cost of total inaction is catastrophic.

Things are gonna get ugly but there is also stability in the system as well as instability. There were times in holocene that the arctic sea ice had almost completely gone (~2million sq km minimum), the Larsen A and B were gone. During that time around 6000 K years ago the world was not that different from today. And not any significant feedback loop started (methane clathrates etc). Just the globe reached another point of stability after the melting of the North american ice sheet. Now having ice free arctic in June and July, this is gonna be eventually nasty...