A set of talking points circulated in support of President Trump’s decision to withdraw the U.S. from the Paris Agreement included this statement:
“The [Paris] deal also accomplishes LITTLE for the climate
“According to researchers at MIT, if all member nations met their obligations, the impact on the climate would be negligible. The impacts have been estimated to be likely to reduce global temperature rise by less than 0.2 degrees Celsius in 2100.”
The researchers in MIT’s Joint Program on the Science and Policy of Global Change who led the relevant analysis find this statement to be misleading, for two reasons.
First, the 0.2 degree-figure used in the talking point reflects the incremental impact of the Paris Agreement compared with the earlier Copenhagen agreement. If you instead compare the impact of the Paris Agreement to no climate policy, then the temperature reduction is much larger, on the order of 1 degree Celsius — 1.8 degrees Fahrenheit — by 2100. This would be a significant reduction in the global temperature rise, though much more is needed if the world is to achieve its goal of limiting warming to 2 degrees Celsius or less.
Second, the analysis accounts only for countries’ pledges under the Paris Agreement, assuming no further strengthening of the commitments in years after 2030. The Paris Agreement is a milestone of the ongoing UN Framework Convention on Climate Change, which is committed to ongoing annual meetings to regularly revisit and ratchet up nations’ climate goals, making them more ambitious over time.
The relevant MIT researchers believe that the Paris Agreement is an unprecedented and vital effort by nearly 200 countries to respond to the urgent threat of global climate change.