As scientists have testified in interviews, global warming isn’t just about killing glaciers and melting them. “Just because the Earth is warming doesn’t mean that more and more blocks of ice are breaking up, it’s not that simple. It’s mainly the wind that moves around Antarctica that affects the ocean Everything that is happening outside Antarctica is linked to it, global warming on a global scale. There is warm water in the depths of the ocean that has always been there, no relation to global warming. […] majority of [ce dernier] Modifies the movement of air currents and this alters the movement of ocean currents, including depth” notes Atsuiro Muto.
Changes in air flow affect the surface of the water and cause hotter currents to rise to the surface. “As we move up an atmospheric circulation, it also modifies the currents below,” confirms Katherine Ritz.
Results for all species
Without the melting of the Thwaites Glacier, water levels around the world would rise by about twenty centimeters by 2050, recalled Gonery Le Coznet, research engineer at the Bureau of Geological and Mining Research (BRGM). In this case, experts predict a melting of mountain glaciers but a “relatively contained melting of the Antarctic and Greenlandic caps”. In less than ten years, it will be a question of “most of the world’s inhabited regions having ports and coastal infrastructure submerged at high tide”.
The Paris Agreement target should not exceed +1.5 °C which, if respected, could stabilize this increase by about 4 millimeters more per year. Even with these figures, during major storms and cyclones, flooding would still be significantly worse. “Danger areas are low areas, such as the great Asian delta, lowland areas of tropical islands, estuaries, or coastal plains such as the Languedoc in France” warns Gonery Le Coznet.
However, as various organizations underlined after COP26 “if the current rates of the largest pollutants do not change, by the end of the century, the planet will warm from +2.4 to 2.7 °C”.
BRGM engineers agree with this forecast: “Above +1.5 °C, the rate of sea level rise will reach 0.5 to 1.5 cm per year. The risk of the collapse of the Thwaites Glacier exceeds these estimates of sea level rise.” The areas that will then be affected will always be lowlands, estuaries, sandy shores. There will be even weakly consolidated reefs, but the impacts will be out of proportion, much faster than in beach standard scenarios which we are working on today”.
a disaster scenario that would lead, 6. According toI IPCC ReportThe accelerated melting of Greenland. Then we will talk about sea level rise of up to 4 meters by 2150. “The problem with such a melting landscape is that there is a risk of running out of time for planning, finance and implementation. Take protective measures,” analyzes the BRGM expert.
In their fall, the Thwaites and other glaciers in this geographic region would also weaken life. “Simulations prove that large colonies of emperor penguins living around Antarctica are in danger of virtual extinction by 2100,” confirms Yann Ropert Coudert, director of research in marine ecology at CNRS. “If the atmosphere changes drastically and the area heats up, […] Their entire life cycle will be modified and they will have to adapt, move elsewhere or perish”.
In order not to condemn some coastal areas and give hope of not seeing these various collapses, drastic reductions in greenhouse gas emissions are necessary today.