For the first time, the researchers quantified what is the social cost of carbon- the measure of economic harm from Carbon dioxide emission in around 200 countries. The first country-by-country estimates of the social cost of carbon show who will pay more than their share, and which big emitters face the least economic impact.
New UC San Diego study’s researchers have developed a data set quantifying what the social cost of carbon for the globe’s nearly 200 countries, and the results are surprising. Although much previous research has focused on how rich countries benefit from the fossil fuel economy, while damages accrue primarily to the developing world, the top three counties with the most to lose from climate change are the United States, India and Saudi Arabia—three major world powers. The world’s largest CO2 emitter, China, also places in the top countries with highest losses.
What’s more worrisome is that the country-level SCC for the U.S. alone is estimated to be about $50 per ton – higher than the global value used in most regulatory impact analyses. Among the most-trusted contemporary estimates of SCC are those calculated by the U.S. Environmental Protection Agency (EPA). The latest figures for global costs range from $12 to $62 per metric ton of CO2 emitted by 2020.
This means that the nearly five billion metric tons of CO2 the U.S. emits each year is costing the U.S. economy about $250 billion. India, whose figures of CO2 emissions are about 2 billion metric tonnes or 2 Gigatons, though is smaller, leads all other countries in its CCS estimates from $50-100 per tonne range, which makes the country suffer $100-200 billion worth of losses.
The researchers and scientists from University of San Diego, published its findings in the Nature Climate Change. These contained the estimates of country-level contributions to the social cost of carbon (SCC) using recent climate model projections, empirical climate-driven economic damage estimations and socioeconomic forecasts. In addition to revealing that some counties are expected to suffer more than others from carbon emissions, they also show the global social cost of carbon is significantly higher.
Recent estimates in other related studies of SCC range from approximately US$10 per tCO2 to as much as US$1,000 per tCO2, however this research has a negative range from $-10 to $100 per tCO2.
In order to model the effects of CO2 emissions on country-level temperatures, the authors use an innovative approach by combining results from several climate and carbon cycle modeling experiments to capture the magnitude and geographic pattern of warming under different greenhouse gas emission trajectories, and the carbon-cycle and climate system response to carbon emissions.
“Our analysis demonstrates that the argument that the primary beneficiaries of reductions in carbon dioxide emissions would be other countries is a total myth,”said Kate Ricke, University of California San Diego assistant professor, who holds joint appointments with the campus’s School of Global Policy and Strategy and Scripps Institution of Oceanography.
“We consistently find, through hundreds of uncertainty scenarios, that the U.S. always has one of the highest country-level SCCs. It makes a lot of sense because the larger your economy is, the more you have to lose. Still, it’s surprising just how consistently the US is one of the biggest losers, even when compared to other large economies.”
Ricke and the authors noted mapping domestic impacts of climate change can help better understand the determinants of international cooperation. The nationally-determined architecture of the Paris climate agreement—and its vulnerability to changing national interests—is one important example.
The findings point to some paradoxical behaviour in the climate governance arena. While the European Union has been an international leader on climate issues, the research shows the threat levels of future warming to be much higher for counties such as the U.S. and India. These nations might be expected to take a leadership role on climate, which historically has not been the case. On the other hand, Canada and Russia, countries which have been slower, and in Russia’s case, almost resistant to any serious action to combat climate change, the low impact is a pointer to the lack of urgency. Of course, believers point out that these countries vastly underestimate the impact in case of extreme scenarios, when they could be facing a flood of immigrants or refugees.
Similarly, low lying Island nations like the Maldives, Mauritius and states in the South Pacific which face the threat of wholesale decimation due to rising oceans will take no comfort from the fact that their small economies have kept them out of these lists, when they in fact, stand to lose pretty much everything.
Overall, the research findings may not move the needle too much, thanks to the strange situation of the US behaving more like a climate change denier right now, and the compulsions both India and China face when taking their large populations into account. Saudi Arabia on the other hand, one of the most wasteful and high emission countries in the world per capita, powered mostly by fossil fuels, has much to think about.