simple explanation of how we know warming is manmade:
http://blogs.ei.columbia.edu/2017/04/04 ... t-natural/
I don't expect you to have detailed answers to these question but you know a lot about this subject.
1) How much must the world reduce CO2 emissions to stop the warming?
2) To reduce CO2 emissions to the point necessary, how will it affect the ability of humanity to make a living and travel about? There's a downside to whatever increased costs come from slashing CO2 & CH4. The poor will carry the load of this downside a million times more than the rich. Do we know it's worth it?
3) I judge how serious people are about something by how much they change their behaviors. Are any of the leaders of the AGW community setting an example by changing their lifestyles such that we can say, "now there's an example I can follow"? I won't get into names but at the top all I see are globalists who want to restrict other peoples lives but not their own.
1) co2 levels in the atmosphere are now 400 ppm. i've seen various estimates of how high co2 can "safely" go, but 450 is one number that's out there. recently co2 growth has been 2.5 to 3 ppm annually.
as alfred has noted, eliminating grain-fed beef is one of the most effective steps an individual can make. according to one report (the atlantic, as i recall), becoming vegetarians is all we need to do. the fossil fuels required to grow corn and beans to fatten steers and the methane release from cattle manure are that big a deal.
2) encouraging the development of renewable power even more aggressively and converting to electric vehicles, powered by renewables, holds promise. the economics of renewables vs fossil power are complicated by subsidies and bad market design (we allow fossil burners not to pay full cost for the trash they put out, that is, pollution). i don't have a good handle on how far renewables will take us, but we're not near the limit, and we should get the economics right, by placing a price on carbon--pollution--that reflects its cost.
i've always though nuclear should play a role. my fellow socialists think i'm dangerous, an apostate. without all of us developing the political will to address waste storage, nuclear is going nowhere.
you ask about the cost of the transition and whether it is worth the cost. what's the cost of not making the tranisition? if sea level does rise by 3 feet by 2050, as some predict, tell me what you think the cost will be to make houston, new orleans, miami, and new york livable? or a 5-foot rise in sea level by 2100. what's the cost?
or a 25-foot rise if the melting of the greenland glaciers picks up. (we'll pretend the antarctic glaciers aren't going to melt.)
3) as for the behavior of elites, dont look to me to hold them up as models. what i will say, though, is that some people you hate--say al gore--have pushed investment in clean technology. many businesses are becoming more efficient, which reduces emissions and results in savings, and investing in renewables as a hedge against volatile energy prices. a global view makes sense. the international carbon markets have driven clean technology in india and china and the like. large companies that get commodities in latin america and africa are investing in their supply communities to make them more stable. farmers everywhere, with the right incentives, have the ability to store large amounts of carbon in agricultural soils. using a sink like that buys some time.
do i think the apocalypse is looming? it's hard to believe, but the evidence is troubling. do i think humans will do what the always do? that is, when you no longer have a choice, you do the right thing. the problem with waiting on climate are the feedback loops, which mean that even if we slow co2 emissions, enough bad stuff will continue to happen to push warming. two examples: (1) with arctic ice melting, the dark water will absorb more heat, whereas ice would have reflected it. (2) melting permafrost, which is happening, releases methane (with 22 times the forcing ability of co2), and warming is further encouraged.
progressives are driving their priuses, eating local, wearing hemp shoes, composting old cotton clothes, putting up solar panels, and being sanctimonious. that could be you.
Put on a a ball gag and masturbate every time you get hungry.