Climate Challenges
Jean Jouzel was the guest of honor at the 2016 HydroGaïa conference. On the future of our planet’s climate, the Nobel laureate offers an uncompromising assessment of the situation. “Stabilizing the greenhouse effect if we want to avoid a catastrophe: that’s simply common sense,” explains Jean Jouzel.
For the Nobel laureate, the situation is dire. But he believes that policymakers are now taking seriously a scientific community that has been warning them for more than 30 years about the dangers of global warming.
Short-term
First finding:“Global warming is unequivocal and unprecedented. It is largely—estimated at 95%—due to human activities.” The main culprits identified are greenhouse gases. Stabilizing the greenhouse effect therefore means reducing emissions. If nothing is done, we can expect“a warming of 4 to 5 degrees Celsius by 2100.”
This is a sudden, unprecedented, and extremely alarming rise in temperature—all the more so because it could continue to accelerate…“A frightening prospect: we’re entering a different world,” comments the climatologist. A short-term danger:“It doesn’t threaten future generations, but rather today’s young people,” he explains.
Irreversible
Reversing the trend? Impossible. When it comes to climate change, there’s no turning back… and we’re paying the price for every moment of indecision in the past. That’s why it’s so important to start adopting responsible behavior today. In practical terms, this means “rapidly and significantly divesting from the fossil fuel sector.”
“Global warming is here; it is inevitable; it is irreversible,” insists Jean Jouzel. The only feasible goal is to keep it within reasonable limits so that we can adapt to it. Limiting the average global temperature increase to below 2 degrees by the end of the century is one of the main points of the Paris Climate Agreement (COP21).
Challenge
“If we want to stay below 2 degrees, at the current rate, we only have about 20 years left to use fossil fuels, ” comments Jean Jouzel. “That’s a real challenge!” And while the terms of the Paris conference remain “far from the goal, ” the climatologist nonetheless welcomes this “universal agreement” signed by the 195 countries in attendance.
Next step: COP 22, to be held in Marrakesh from November 7 to 18, 2016. Following the Paris Agreement, this meeting is anticipated as a“COP of action.”“We have to act now! It’s technically possible, and for younger generations, the challenge is exciting: changing the world, rather than continuing on the same path.” It’s a low-cost revolution, the climatologist assures us: “Staying below 2 degrees would amount to reducing GDP by roughly one year’s worth every 30 years. It’s not suicidal; it’s simply another form of development, ”he concludes.
If nothing is done…
With an average temperature increase of 4 to 5°C, serious consequences are expected in the Mediterranean region as well as around the world…
- ocean acidification: the oceans are now said to be twice as acidic as they were at the beginning of the last century, posing a direct threat to fish and coral reefs;
- “extreme weather events”: droughts, floods, heat waves, cyclones… In our regions, an increase in extreme weather events of the “Cévenol” type is expected;
- risks to populations—including climate refugees, water scarcity, and food shortages—as well as security risks: global warming is, in fact, contributing to political instability in many regions;
- environmental issues: loss of biodiversity, pollution, health…;
- irreversible phenomena: rising sea levels, for example. Along our coasts, sea levels could rise by nearly 1 meter in some areas—a serious threat to low-lying regions, such as the Camargue.
Jean Jouzel is one of the world’s most renowned climatologists and glaciologists, having received numerous awards: the CNRS Gold Medal in 2002, shared with Claude Lorius; the Nobel Peace Prize in 2007, shared with the IPCC (Intergovernmental Panel on Climate Change) and Al Gore; and the Vetlesen Prize in February 2012.