Thread by @BjornLomborg

Paris climate policy will cost a sizable fraction of 21st century prosperity

Two new, explosive, peer-reviewed papers show net-zero/1.5°C :

Benefit $4.5 trillion/year

Cost $26.8 trillion/year

Total loss is $1,800 trillion over the century

We must do better

🧵 + refs

New special issue of peer-reviewed journal 𝘊𝘭𝘪𝘮𝘢𝘵𝘦 𝘊𝘩𝘢𝘯𝘨𝘦 𝘌𝘤𝘰𝘯𝘰𝘮𝘪𝘤𝘴

First climate economic article shows cost and benefit of 1.5°C target

worldscientific.com/doi/10.1142/S2…
worldscientific.com/doi/10.1142/S2…

Climate benefit of 1.5°C policy is less than 0.5% of global GDP by mid-century and 3.1% by 2100

This is an overestimate, as it assumes change from absurdly high damage (RCP8.5) to 1.5°C

Based on new meta-analysis, 39 papers w/61 published estimates

worldscientific.com/doi/10.1142/S2…

Climate benefit of 1.5°C non-trivial

Economic costs are larger every year of this century

+ Cost wildly too small as paper assumes perfect climate policy with global, single, increasing carbon tax

In real life 2x higher or more

worldscientific.com/doi/10.1142/S2…

Second climate economic article shows more realistic costs of 1.5°C and its close cousin Net-Zero by 2050

worldscientific.com/doi/10.1142/S2…

Paris climate policy benefit low

Theoretical cost higher

Realistic cost of 1.5°C much higher again

worldscientific.com/doi/10.1142/S2…

Paris climate policy benefit low

Theoretical cost higher

Realistic cost of 1.5°C much higher again

Realistic cost of Net-zero by 2050 even higher

worldscientific.com/doi/10.1142/S2…

MIT paper only shows consumption costs, but authors shared GDP losses

They also shared their GDP development over century in 2007 US$ (roughly like UN SSP2)

Adj to 2023 US$ using BEA Table 1.1.9

worldscientific.com/doi/10.1142/S2…

All figures are undiscounted

Since costs come before benefits, any discounting makes the benefit-cost ratio over the century even worse

Without discounting, each dollar delivers less than 17¢ of climate benefits

With 5% discounting it is less than a dime

We need to do better:

Green R&D is the way to dramatically cut the cost of going green

If we can innovate green energy to be cheaper than fossil fuels 𝘦𝘷𝘦𝘳𝘺𝘰𝘯𝘦 𝘸𝘪𝘭𝘭 𝘴𝘸𝘪𝘵𝘤𝘩

e.g.


cambridge.org/core/books/sma…
bostonglobe.com/opinion/2015/1…

Paris climate policy will cost $27 trillion each year throughout the 21st century

Each dollar delivers just 17¢ of benefits

Our politicians need to do better


worldscientific.com/doi/10.1142/S2…
worldscientific.com/doi/10.1142/S2…

promises are far more wasteful than useful

I wrote a WSJ oped, detailing the new peer-reviewed studies that show
Paris climate promises could cost $27 trillion each year this century


wsj.com/articles/net-z…
archive.vn/DueaA