Onus still falls on national governments to cut emissions to stave off worst impacts of climate change, Yale researchers say
Individual cities, regions and businesses across the globe are banding together determinedly to confront climate change – but their emissions reductions are relatively small and dont fully compensate for a recalcitrant US under the Trump administration, a new study has found.
A cavalcade of city mayors, regional government representatives and business executives from around the world will convene in San Francisco next month for a major summit touting the role of action beyond national governments to stave off the worst impacts of climate change.
But the greenhouse gas cuts offered up by these entities are relatively modest, according to new research, placing the onus on nations to raise their ambitions even as the US, the worlds second largest emitter, looks to exit the landmark Paris climate agreement.
An evaluation of climate change pledges by nearly 6,000 cities, states and regions, representing 7% of the global population, and more than 2,000 companies that have a combined revenue comparable to the size of the US economy, found a total projected reduction of between 1.5bn to 2.2bn tons of greenhouse gases by 2030.
But globally these emissions cuts fall short of enabling countries to avoid breaching agreed thresholds for dangerous warming that will trigger increased heatwaves, mightier storms, rising seas and displacement of people.
When we look at the individual pledges [by cities, regions and businesses] the impact isnt that large so we absolutely need national governments to pull through and do a lot of the heavy lifting, said Dr Angel Hsu, the director of Data-Driven Yale, which led the study.
The actions of cities, companies and states arent insignificant but they cant do it by themselves. This shows everyone can be doing more. The current reductions are woefully inadequate and hopefully the actions of other entities will give national governments the confidence to be more ambitious.
The analyzed reductions, taken from nine high-emitting countries such as the US, China, India and Brazil, as well as the European Union, overlap with some national efforts that increase the total contribution of emissions cuts.
But this action isnt sufficient to bridge a gap between the Paris agreements goal to avoid 2C (3.6F) of global warming, with an aspiration of avoiding a 1.5C increase, and the insufficient emissions reductions put forward by the deals nearly 200 national signatories.
The agenda of the Trump administration risks making this goal even more challenging. Trump has promised to withdraw the US from the Paris agreement and has unveiled a plan to weaken vehicle emissions standards that could result in more than 1bn tons of extra carbon dioxide over the next 15 years. Last week, Trumps Environmental Protection Agency announced a watered-down climate policy for the energy sector that might even result in emissions rising from coal plants.
Even if every Paris commitment is fully implemented, the world is on track to warm by around 3.3C by the end of the century. Pledges by the likes of Berlin, the Coca-Cola company or even an economic powerhouse like California while welcome, are not sufficient, said John Sterman, the director of the MIT system dynamics group.
The world is in a desperate race between accelerating climate change and the innovation needed to cut emissions before its too late, said Sterman. Cities, states, and business are in the lead, but they face stiff headwinds from weak national policies and the continued efforts of fossil fuel interests to undermine the innovation we need.
Global greenhouse gas emissions rose slightly last year, after a short period of stasis, highlighting the looming scenario whereby as-yet unproven technology will be need to be deployed at a mass scale to suck CO2 directly from the air or capture and bury it after burning vegetation, known as biomass, for energy.
We are already in an overshoot situation and its likely we are already going to have to need to remove carbon from the air, said Klaus Lackner, the director of center for negative carbon emissions at Arizona State University. The idea we just tighten our belt a bit isnt going to solve the problem. We need to stop using the atmosphere as a dumping ground, abandon fossil fuels, find other sources of energy and deal with the carbon debt we already have.
Cities getting involved is good and important but we havent really acknowledged how big and serious the challenge is. We are whistling in the dark.