Danger levels: What will the world be like if we miss our climate targets?
Hurry up. The scale of action we need to protect the climate is huge, it has to happen quickly, and the plans on the table fail.
In 2015, almost every country in the world agreed to limit temperature rise to 2 degrees Celsius (3.6 F) above pre-industrial levels and to aim for a limit of 1.5 C as part of the ‘Paris Agreement. So far, real commitments to reduce fossil fuel consumption and other measures to reduce greenhouse gas emissions into the atmosphere – if met – will only get us back to 2 , 7 ° C of warming, warned the UN.
At the end of this month, world leaders will gather in Glasgow for the 26th edition of the United Nations Climate Change Conference. And the pressure is strong to propose much more radical measures to achieve the Paris target.
But what difference does a fraction of a degree make? Well, a lot, according to the vast body of scientific research conducted globally to assess the impacts of climate change.
With climate-induced disasters already happening across the world, the scale of the problem may seem unmanageable. Yet while science paints a grim picture, it also shows that limiting warming by what appears to be a tiny amount can save millions of lives, protect vast swathes of land from degradation, and give other species a boost. chance of survival.
According to the latest report from the Intergovernmental Panel on Climate Change (IPCC), released in August, global temperature has already risen by 1.07 ° C since the industrial revolution. And we can already see that just one degree of warming has had a huge impact.
Every inch of sea level rise could put millions at risk
Take the rise in sea level. So far, we have raised the average sea level by about 20 centimeters (7.9 inches) since 1901, according to the IPCC.
It may not seem like much, but it is already forcing people to leave their homes all over the world. According to the Internal Displacement Monitoring Center, hundreds of thousands of people are displaced by flooding every year in the lowlands of Bangladesh.
According to the data-driven climate website Carbon Brief, which analyzed 70 peer-reviewed scientific studies in 2018, with a warming of 1.5 ° C, we envision a global sea level rise of 48 centimeters by the end of this century, compared to 56 centimeters if we reach 2 degrees.
And just eight centimeters makes all the difference for millions of people. According to the IPCC, every 10 centimeters of sea level rise affects up to 10 million more people around the world.
A little warming means a lot of rain
The latest IPCC report indicates that the type of “extreme precipitation event” that before the Industrial Revolution only occurred once every 10 years, now occurs about 30% more often. At 1.5 degrees of warming, the risk increases by 50% – and the severity of the event also increases, becoming 10.5% wetter. At 2 degrees, such an event becomes 70% more likely and 14% wetter.
For a country like India, that means a very different future. According to insurance company Munich Re, floods and landslides caused more than 700 deaths and $ 11 billion (€ 9.5 billion) in damage in 2018 and 2019.
According to Carbon Brief, with 1.5 ° C warming, the economic damage caused by flooding in the country would increase by more than three and a half times and to 2 degrees, almost five and a half times.
Longer and drier droughts
While some areas of the planet will become wetter, others will become drier, with equally catastrophic results. In 2018, the IPCC said limiting global warming to 1.5 C versus 2 C could mean half as many people exposed to water stress.
In its latest report, the IPCC says what would have been a decade-long drought before the industrial revolution is now 70% more likely. At 1.5 C they become twice as frequent, and at 2 degrees they will occur 2.4 times more often.
According to the Carbon Brief, globally, the average duration of a drought increases by two months with 1.5 degrees of warming, four months at 2 degrees, and 10 months with 3 degrees of warming.
In 2019, the World Food Program said 2.2 million people in Central America’s “dry corridor” suffered crop losses due to drought and five consecutive years of erratic weather conditions. In February of this year, that figure rose to nearly 8 million, partly because of the economic impact of the pandemic, which has worsened “years of extreme weather events”, but also because of hurricanes Eta and Iota, which hit Central America in November 2020.
How things get worse in the region will depend on what climate action we take. According to Carbon Brief, at 1.5 degrees warm, the average duration of droughts in Central America will range from five months, to 2 degrees warm by eight months, and 3 degrees by 19 months.
Small numbers, big risks
And alongside the drought comes the heat waves and the perfect conditions for the kind of fires that have roared everywhere. from California to southern Europe and from Indonesia to Australia in recent years. According to the IPCC, limiting warming to 1.5 ° C from 2 ° C could reduce the number of people frequently exposed to extreme heat waves by around 420 million.
While these numbers are staggering, the human cost of these seemingly small increases in warming is nearly impossible to comprehend. Destroyed lives, hunger, homelessness and poverty mean unquantifiable suffering. And they will exacerbate or precipitate political tensions in ways that we cannot predict, leading to conflicts that we can only yet guess at.
What we do know for sure is that when it comes to climate change, seemingly small numbers can make all the difference.