will permafrost melt release so many greenhouse gases that it stops mattering if we reduce emissions?

will ocean acidification really devastate sea life?

what happens if hurricanes do get significantly worse?

can we contain wildfires that increase in range, frequency, and intensity while all of the other stuff is going on?

what happens if we are wrong on climate sensitivity and we're really heading for a >5 degree temperature rise in our lifetimes due to increasing feedbacks?





It is very important to understand that this isn't a distant future problem. This is already happening. This is already killing people, exacerbating droughts, etc. It will continue to get worse. 2030 will be worse than now. 2050 will be worse than 2030. This directly hurts your children. Quoting Joseph Romm..."Climate change will have a bigger impact on humanity than the internet has had."



Maybe we shouldn't miss our targets by too much then?



*Additional major sources for much of the above are the IPCC reports, book 1, book 2, Royal Society update, and the US Climate Assessment. Some of this is also just common sense...as sea levels rise, things like runways that will now be below sea level become an issue, and many major airports were built on coastlines. Most of these increase in scale as temperatures rise. For example, GDP losses are likely in the 1-2% range with heavy mitigation and the 5-10% range without it. Crop production likely drops by 5-10% per degree of temperature increase, especially above 2 degrees. Sea level rise probably doubles with high emissions vs low emissions.It is very important to understand that this isn't a distant future problem. This is already happening. This is already killing people, exacerbating droughts, etc. It will continue to get worse. 2030 will be worse than now. 2050 will be worse than 2030. This directly hurts your children. Quoting Joseph Romm..."Climate change will have a bigger impact on humanity than the internet has had."Maybe we shouldn't miss our targets by too much then?

How do we stop global warming?

To be blunt...I don't think we can. Given what it would take from the first section of this post and the fact that people have known about this for many years and only made the problem worse, I don't think we'll actually come close to stopping it. I'm hoping we'll at least make it not as bad as it can be, but we actually seem to be getting worse. In the US at least, the GOP over the last decade has switched to open science denial. Voters rewarded them by electing Trump and giving the GOP control of all branches of government. When faced with a comparatively small refugee crisis, the world failed to band together and deal with it.



Also, much of the above is locked in. Even if we cut all emissions today, warming would continue due to what we've already emitted. It just wouldn't be as bad as it will be if we keep doing what we're doing. A better question then is probably, 'What can I do that will have an impact?' My honest thoughts on that are:

this is a global problem and a classic tragedy of the commons; individuals cannot change much, but leaders can; base your vote on this...do not vote for anyone who lies about this unless all options do, then vote for the option whose lies are least egregious...this is the biggest impact most individuals can have educate the people around you so that they do the same; shut down the people around you who lie about this and limit their influence on others as much as you can try not to have children, and if you do, try not to have too many





That's basically it...things like an individual installing solar panels on his roof don't really matter. There are some societal things we can push for that have great benefits at a low cost like increased telecommuting, increased access to birth control, incentives for increasing building energy efficiency, and so on, but those are hard to make progress on at the individual level.





Another question you might have instead is, 'How can I prepare for it?' I've created a large number of tools and visualizations comparing cities. My gut is to move to a city that should fare reasonably well. I'll try to start putting together city profiles and give more detailed advice on this, but a really crude summary is:





target

large source of freshwater that is not snowpack or glaciers cool temperatures not coastal not near an area likely to collapse stable and somewhat self-sufficient country not located on permafrost not likely to experience a catastrophic loss of rainfall not a massive wildfire risk not right on the threshold of getting tropical diseases Combining those, you get a few obvious places that seem nice and a few obvious places to avoid. I know the US better than everywhere else so I'm biased towards it, but:



probably good places great lakes region (both US and Canada) appalachian region Pacific NW northern Europe central Europe UK southern South America probably bad places anything equatorial western/southwestern US; basically anything west of the line from the Texas/Louisiana border to the Kansas/Nebraska border Middle East anywhere that is already uncomfortably/dangerously hot sometimes southern Europe Central and SE Asia Peru (i.e., dry, glacial melt areas) southern Florida and Louisiana; anywhere with sunny-day flooding really There was an attempt at making a global scale for this, and it can be found here

Is there really no hope?

There is some tiny chance that we win the lottery. Examples of extremely unlikely things that are still technically feasible are:

we solve fusion and rapidly roll that out we find some very cheap way to pull carbon out of the air and store it permanently; keep in mind that the carbon got there in the first place from energy production and it takes more to remove it, so we're talking undoing the past 150 years of energy production while still providing new energy for ourselves; good summary here and an example of an unusual idea that shows a bit of promise is here solar and wind become insanely cheap, we can get it without emissions-heavy mining, we get massive breakthroughs in battery technology, and we opt to shut down fossil fuel plants and replace them with this + all switch to electric vehicles powered by this; for reference on the scale, replacing all US power plants with solar means enough solar cells to cover roughly all paved surfaces in the US, so try to imagine that for the entire world; note also that's just for power plants, so that wouldn't provide fuel for cars, air travel, etc. That's basically it. We've bet everything on technology that doesn't exist and scientists have told us we shouldn't bank on. The analogy that I've found myself using often is that our strategy with greenhouse gases is like signing up for a class, skipping all assignments, skipping all tests, and hoping to score a 250/100 on the final to make up for it.

Summary

There's not a realistic path to limiting warming to 1.5 or 2 degrees and the world is not seriously attempting it. There is a realistic path to maybe keeping it under 4 degrees. The problems get worse as temperature rise goes up, so we should try to keep it as low as possible but we should stop lying to ourselves about it. We've already locked in significant problems, including large-scale death, economic losses, and most likely conflicts/collapses. The best thing you can probably do as an individual is elect leaders committed to mitigating this and prepare your family.





Now for some stretch ones that are poorly understood currently (note that means we could be overestimating them but also that we could be underestimating them):