There is a 5% chance of limiting average global warming to under two degrees Celsius (3.6 degrees Fahrenheit), the target set in the 2015 climate-rescue Paris Agreement, researchers say
PARIS, France (Aug. 1, 2017) — There is a 5% chance of limiting average global warming to under two degrees Celsius (3.6 degrees Fahrenheit), the target set in the 2015 climate-rescue Paris Agreement, researchers said on Monday, July 31.
And chances of meeting the lower, aspirational 1.5ºC goal, also listed in the 196-nation pact, were a mere 1%, they wrote in the journal Nature Climate Change.
A US-based expert team used projections for population growth to estimate future production, and related carbon emissions from burning fossil fuels.
Based on these data, “the likely range of global temperature increase is 2ºC to 4.9ºC, with median 3.2ºC and a 5% chance that it will be less than 2ºC,” they wrote.
Their calculations were not based on worst-case-scenario predictions of unabated energy use, the team said, and provided for ongoing provision for efforts to curb fossil fuel use.
However, it does not provide for the possibility of a sudden, massive shift to renewable energy.
“Achieving the goal of less than 1.5ºC warming will require carbon intensity to decline much faster than in the recent past,” wrote the team.
The world’s nations concluded years of acrimonious negotiations two years ago to conclude the Paris Agreement on climate change.
They undertook to hold global warming to “well below” 2ºC over pre-Industrial Revolution levels, and to strive for 1.5ºC in a bid to stave off disastrous sea level rise, droughts, storms and other climate effects.
Experts have long warned that even 2ºC would be a tall order.
The UN’s climate science panel recommends a 40-70% cut in greenhouse gas emissions from fossil fuels by 2050 from 2010 levels.
The Paris Agreement is less precise, with signatories aiming for emissions to peak “as soon as possible”.
The UN estimates that the global population will increase from about 7.5 billion today to 11.2 billion by 2100, putting additional pressure on energy resources.