I don't. It's an improvement, certainly, in that the unhappiness has some kind of effect to deal with. But really it needs to give the player decisions to make.
Oh, I think it can be improved too. I'm not sure how much the game would need to change though in order to give the player some meaningful decisions to make.
For one, I think it needs to be a little bit clearer to the player the correlation between GW and unhappiness in cities. For example, considering the Environmentalism civic, does it have any benefit other than what it lists? Because the +1

and reduced unhealthiness did not sell the civic to me in my game.
The main thing I like about the new system:
- It's at least based on a physical model with parameters and thresholds
- It doesn't just turn everything to desert, and focusing on the polar regions first means it's less annoying. Sometimes a tile may be changed to something more productive (which is possible in RL - it's more the fact it adds more extremes and changes some local climates that makes it costly to adapt to)
- It has an impact on cities
mad
so ignoring it completely is hard to do.
- It isn't caused by nuclear warfare.
- There are buildings which reduce pollution (recycling centre and public transit system).
I think forest preserves on jungles should be more valuable. Currently there's still not enough incentive to keep jungles for all that time, but if they added maybe 2

and some

to the nearby city then keeping them might be worthwhile. Actually I still don't think that's enough but I'm struggling to think of anything that would work.
Or maybe the player could invest part of his/her budget into offsets and this would help reduce the unhappiness (though the way I've described it there makes it pretty one-dimensional and probably boring). For the decision to be interesting it probably needs to be more than, "Should I spend this much gold to reduce unhappiness in key cities?".
Maybe there could be a new building whose main effect is to reduce

caused by GW at some sort of cost to the city?
e.g.
Sustainable City Project
Costs:300

Effects: -10% commerce, -50% GW anger, -15%

from population
Available: Computers
Or 500

without the commerce penalty could work better.
On another note, I only just noticed this thread is in its own subforum now. Maybe this feedback is meant to go in another thread?