New commitments by Europe, China, and the United States to cut their greenhouse gas emissions still aren’t to sufficient to head off dangerous levels of climate change, a new analysis warns.
In November, the United States and China forged an agreement that wedded the former country to an all-new pledge to cut its emissions 26 to 28 percent (below 2005 levels) by 2025, while setting China the goal of getting 20 percent of its energy from renewables by 2030 and peaking its emissions that same year. And in October, the European Union hashed out a new deal between its member countries to cut their collective emissions 40 percent (below their 1990 levels) by 2030.
But scientists and policymakers have agreed that global temperatures must not rise more than 2°C over their pre-industrial levels in order to avoid the climate change that could lead to potentially catastrophic changes in storm patterns, flooding, droughts, heat waves and other extreme events around the globe. According to new modeling done by an international team of researchers, the latest pledges from China, the U.S., and Europe, along with those from the rest of the international community, still leave temperatures rising well above that threshold.
“The pledges made so far lead to earlier emission peaking in many countries, with 1–1.5 °C less total warming than without these policies, but not sufficient to meet the 2°C target,” said Massimo Tavoni, who coordinated the project in the press for the journal Nature Climate Change. Another recent analysis by the Massachusetts Institute of Technology came to a similar conclusion back in August — though that was before the commitments unveiled in October and November.
The Fifth Assessment Report from the United Nation’s Intergovernmental Panel on Climate Change “clearly highlighted the level of global effort needed to stabilize the climate,” Tavoni added. “But a quantitative assessment of the regional implications of post 2020 climate policies, which brings together different modeling tools was missing. This is what the paper has achieved.”
The researchers hailed from six different European institutions, and used six different climate simulators. Specifically, they modeled three scenarios: what would happen without the current pledges, what will happen with them, and what would be necessary to hold to the 2°C limit. Because carbon emissions are cumulative, the world can only emit so much this century before breaking past 2°C becomes inevitable. That “carbon budget” for the 21st Century stands at roughly 1,000 gigatonnes of carbon, and the world has already emitted a bit over half of that. In fact, if the latest pledges from Europe, the U.S. and China are not factored in, the rate at which the world is emitting would hit the carbon budget limit by 2040.
With the new commitments, China’s emissions will be cut in half, the European researchers found. But the Asian economies as a whole will still emit approximately 1,000 gigatonnes more than the 2°C limit allows for all by themselves.
“A large part of the emission reductions, if to be realized at lowest cost, would come from emerging economies such as China or India,” said Elmar Kriegler, a senior scientist at the Potsdam Institute for Climate Impact Research, and one of the study’s co-leaders. “If a future climate agreement aims to tap into these abatement potentials, it would likely need to include mechanisms to compensate developing countries for part of their abatement effort.”
Wealthier countries in the United Nations (U.N.) have put together a fund to begin to provide that compensation, and it just recently met its goal of $10 billion in pledges. But that remains well short of the needed investment: a recent U.N. report found that, by 2050, developing nations will need to spend between $250 and $500 billion every year to adapt to climate change. And that’s assuming temperatures hold to a 2°C rise. According to Tavoni, the European researchers also used their modeling to look into this question, and found that $100 to $150 billion per year by 2030 “could achieve efficiency and cover the total investments in low carbon technologies needed in developing countries for the 2°C target.”
International climate negotiations just concluded in Lima, Peru. And while they did not finalize any hard commitments, or settle the matter of how or how much the advanced economies will compensate poorer nations for their efforts, the talks did hammer out something of a framework within which countries can make their pledges in the run-up to a final round of talks that will occur in Paris at the end of 2015.