The climate commitments announced by Presidents Barack Obama and Xi Jinping in China are momentous given the political status quo, but they still leave human civilization on a catastrophic trajectory, a Hill Heat analysis shows.
The non-binding targets agreed to in Beijing — that China would peak in emissions by 2030 and the U.S. would accelerate emissions cuts to reach 80 percent of current pollution levels (74 percent of 2005 levels) by 2025 — are a positive step forward. Without such targets catastrophic warming is guaranteed.
President Obama reaffirmed that limiting global warming to less than 2°C (3.6°F) above pre-industrial levels is his goal, claiming the announced targets “means the United States is doing its part to contain warming to 2 degrees Celsius.”
What do the announcements actually mean in the context of what is needed?
Below, we explore the targets in the context of a “Russian roulette” 2C pathway, with pollution levels that scientists estimate lead to a one-in-five chance of exceeding 2C. (Ed.: Russian roulette odds are actually a bit better.)
By 2030, US and China alone will have emitted about 80% of the carbon budget, leaving the other 75% of the global population with little to spare. By 2050, US and China will have emitted about 160% of the carbon budget, making the “Russian roulette” scenario impossible. To be clear, even 2C warming is highly risky, to say the least (Hansen et al, 2013).