Let's recap Hansen's points.

According to him, we need to invest in the following four things:

an end to coal without CCS
reforestation/afforestation in the tropics
biochar (agrichar, terra preta) and soil carbon sequestration; a transition from slash-and-burn to slash-and-char
biomass coupled to CCS

Let's do it!

This campaign seems focused on an international effort to create a global climate treaty that transcends Kyoto. Honestly, I don't understand this thrust. Our biggest challenge is to turn our own government around, climate-wise. Until and unless we do, why expend energy on  a future global treaty that will have to be agreed on and ratified by hundreds of other countries? The USA has the chief responsibility for mitigating global warming, via our congress in Washington DC. But what has come out of congress so far (the Boxer bill) has no basis in science and if passed next year will condemn us to utter failure. Its provision of an 80% CO2 reduction by 2050 means a paltry 2% point reduction in emissions each year. Together with the ill-advised and subversive plan for carbon trading, this means existing coal plants will continue to operate for their lifetime. Add on to that the proposed subsidies and tax breaks for carbon sequestration (which is unlikely to prove feasible on a global scale), and we face a full-scale unabated coal-based global energy economy. McKibben would be better off finding a concrete target: supporting carbon taxes, stopping carbon trading and subsidies, and focusing on stopping coal in its tracks. He needs a detailed legislative energy agenda to back all of this up, not just homilies about international solidarity. Time is too short for virtual campaigns.

For offering Hope when there is none

If the graph on this video is correct, the CO2 concentration in our atmosphere needs to be lowered way below 350 ppm.

@wolverine: reading through hansen et al materials you see that there is a range of values they believe are somewhere near right and 350 is the high end of them and each mention of 350, the right to lower that number in future is retained.

at the same time 350 is something like the maxed-out physically possible of today's knowledge and equipment. cut human emissions to zero without starving millions of people; capture and store 50 ppm as cost-effectively as we can.

@lorna: every regional and national government, every organization, every group, everyone -- using 350 as a guideline -- has to throw out giant piles of "answers" they've accumulated for use over the next 40-100 years.

for instance, the EPA said last year that the L-W bill would stabilize at about 481 ppm if the world followed its example. combine that with the california finding that to meet "80% by 2050" goals, a carbon market would only go 40% of the way there, and you have a lot of dead excuses lying around.

i really think knowing where you're going is important to people.