In a way, that's not surprising. The past 12 months have been scorching, with a combination of warm El Niño conditions and signs of human-induced warming leading to heat waves and extreme weather events around the world.
“This El Niño maximum builds on a baseline climate that continues to warm due to climate change,” Andrew Dessler, a climate scientist at Texas A&M University, said in an email. “It's the combination of those things that makes the Earth so hot.”
But does this mean that the world's most famous climate change goals will not be met? Not exactly.
Here's what you need to know:
Where did the 1.5 degrees Celsius goal come from?
The 2016 Paris Climate Agreement commits some 200 countries to keep global average temperatures no higher than 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial levels and to “continue efforts to keep them below 1.5 degrees Celsius.” ” Agreed. The latter additions are mainly due to pressure from small island states, which are at risk of being wiped out by rising sea levels if temperatures rise further.
Scientists have shown that temperature increases can be reduced. Warming to 1.5 degrees Celsius could help coral reefs survive, protect Arctic sea ice and reduce deadly heat waves.
Momentum is growing towards this more ambitious goal, even as carbon emissions continue to rise. Activists and environmentalists have advocated “1.5 to stay alive,” pointing out that achieving that goal will require significant reductions in emissions by 2030.
Does this mean we have missed the 1.5 degree temperature target?
no. Although there is actual disagreement about what exactly constitutes a violation of the standard, scientists and policymakers agree that it is not a single 12-month period, but an average of multiple years. I agree that it must be done. Scientists estimate that, absent dramatic emissions cuts, that will happen sometime in the 2030s. But other single-year or 12-month periods may cross the line by then.
Is it still possible to avoid temperatures exceeding 1.5℃?
Most scientists say that temperatures above 1.5°C are inevitable. “The 1.5 degree limit is more dangerous than a doornail,” Columbia University climatologist James Hansen said on a call with reporters late last year.
Scientists and economists use complex models to try to predict how quickly the world can transition away from fossil fuels. The Washington Post analyzed 1,200 modeled paths for the world to transition to clean energy and found that only four of them involved significant overshoots or speculative technologies that have yet to be achieved. We found that this shows that we are meeting the 1.5 degree goal without the use of carbon capture (such as large-scale carbon capture). exist. At the moment, many experts believe the economy is too stuck on fossil fuels to transition quickly enough to 1.5 degrees of change.
Does it mean we will pass a catastrophic tipping point?
That's an even harder question. Scientists don't know exactly when certain tipping points will occur, such as the collapse of Greenland's ice sheet or the release of greenhouse gases from thawing permafrost. Predicting and modeling such catastrophic changes is extremely difficult.
And 1.5°C is not a magic threshold. This does not mean that the Antarctic ice sheet will collapse and ocean circulation will stop as soon as this number is exceeded. But one thing is certain: With each tenth of a degree of warming, a tipping point becomes more likely. 2 degrees is worse than 1.9 degrees, and 2 degrees is worse than 1.8 degrees.
And every 10 degrees will put an even greater strain on the infrastructure and systems the world has built: power grids, housing, and livelihoods. Our modern world was not designed to be this hot. At some level, the final temperature of the Earth is not the most important thing. This is where countries can actually reduce their carbon emissions to zero and completely stop contributing to future warming.
