* It costs $0.50 per tree planted,
* trees absorb 1 ton of CO2 each,
* Teslas cost $15,000 more than regular cars
* Teslas emit 1 gallon of fuel less than regular cars per 25 miles (starting after 50,000 miles: https://www.wsj.com/articles/SB10001424127887324128504578346...)
* 1 gallon of gas produces 20 lbs of CO2
* Cars will last 250,000 miles
Then we have Teslas saving us: ( (250,000-50,000) miles * 1 gallon per 25 miles * 20 lbs per gallon)/$15,000 = 10 pounds of CO2 saved per dollar spent on Teslas, compared to 4,000 pounds of CO2 saved per dollar spent on planting trees.
This is why I associate myself with climate skeptics despite their negative reputation. An economic analysis of climate change seems to suggest that the world will be worse off with climate change mitigation, as it's currently being practiced, than with climate change itself.
Edit: It's actually quite interesting to see that your username resembles the name of Bjorne Lomborg, a famous scientist who often makes arguments about the economics of climate change and comes to similar conclusions as I do.
There could be an even cheaper scheme for climate change mitigation that we haven't thought of (like stimulating plankton growth with iron, for instance).
And it's actually possible that the total cost of allowing climate change to progress unmitigated may actually be cheaper than 50 cents per ton of CO2; creating more fertilizer for farmland and building seawalls may become cheaper 100 years from now than the future growth-adjusted value of the proposed carbon-based tax credits.