The glaciers will use centuries to reform, even if global warming up

When we talk about lost ice it is not possible to rewind the tape as if nothing had happened. The mountain glaciers eroded due to global warming they will use centuries to reformif we definitively exceed the +1.5 ° C of Global Warming fixed as a threshold insurmountable by the Paris agreements. Even if we were to return below this limit, thanks to technologies for the capture and storage of CO2 and a virtuous action on emissions, reforming the lost glaciers will require the time of entire generations. One more reason to preserve them from the beginning.

A group of scientists from the University of Bristol in the United Kingdom and the University of Innsbruck in Austria presented, in a study published on Nature Climate Changethe first global simulations of the changes of glaciers from here to the year 2500 under the so -called Climate Overshoot scenariosthat is, they foresee a global warming that temporarily exceeds the limit of + 1.5 ° C reaching up to + 3 ° C, and then cool down again. This is because, as Fabien Maussion, associate professor of polar environmental changes at the University of Bristol and the author of the work explains, “current climatic policies are putting the land on a trajectory close to + 3 ° C”.

In addition, the significant increase in the temperatures recorded in recent years – 2024 has pulverized any previous global warming record – indicates that the “official” overcoming scenario of the limits of the Paris agreements is now very probable.

The simulated scenario in the study involves an increase in the global temperatures it leads to + 3 ° C around 2150, before returning to + 1.5 ° C by 2300 (due to decisive policies on the climate implemented late) and stabilize. Essentially A future with clear zero emissions dangerously moved over time. Perhaps a little too much at there, overestimating the recovery capabilities of the glaciers.

«Our goal was to find out if the glaciers could regenerate if the planet were to cool again. Is it a question that many ask themselves: will the glaciers reform during our life, or in that of our children? Unfortunately, our results indicate no »adds Maussion.

Under these climatic conditions, the world glaciers would lose a 16% more mass by 2200 and 11% more by 2500 – in addition to 35% already sentenced to melt even if we remained within + 1.5 ° C. This additional merger water would make the raising of the seas level even more accentuated.

The simulations were obtained using an open source model developed by the University of Bristol to simulate the past and future of glaciers around the world, excluding polar glacial caps.

«Our models show that many centuries will take us, if not millennia, because the great polar glaciers recover from a 3 ° C. For smaller glaciers, such as those of the Alps, Himalayas and Tropical Andes, the recovery will not be visible in the next generations, but It will be possible by 2500It clarifies Lilian Schuster, researcher in atmospheric sciences of the University of Innsbruck, an expert in climate and cryosphere.

The problem is also relevant for the water reserves of the populations that live downstream of the mountain glaciers, made up of the water of the beam. In a growing melting scenario of the ice, the water downstream increases; When the glaciers reform, they begin to Keep more water upstream in the form of ice. The study provides that almost half of the glacial basins studied will be retaining water in the second of the scenarios described beyond the year 2100. An important fact to try to imagine the consequences that this could have on the populations that depend on the water of the difference.

The final message? Overcome even temporarily The + 1.5 ° C of global warming ensures a loss of ice that lasts for centuries, even if the temperatures then return to the ranks. One more reason to keep as close as possible to this safety limit.