The goal of containing global warming, compared to the pre-industrial period, at +1.5 degrees may no longer be enough. This is suggested by a new study published in the important scientific journal Nature. According to scholars, polar caps are melt at an ever faster pace. The most direct consequence is the raising of the sea level which will constitute a danger for the populations that live 10 meters above sea level (about a billion in the world) and 1 meter (about 230 million people). This could trigger a mass migration towards the innermost areas of each country.
The dissolution of polar caps
The dissolution of the polar caps has quadrupled from the nineties to today and represents the main cause of sea level in analyzing. According to the authors of the study (Chris R. Stokes, Jonathan L. Bamber, Andrea Dutton and Robert M. Deconto), the target of the Paris agreements – to limit the increase in world temperature to 1.5 degrees more than pre -industrial levels – is “too high”. If this trend is maintained, the sea level will rise by several meters in the next centuries. To avoid these catastrophic consequences, scholars hypothesize it is necessary to limit the increase in global temperature around the extra degree. A very distant goal at the current rhythms.
Climate change, in fact, are already in progress. From 1901 to 2018 the average global level of the sea (GMSL) increased by 20 centimeters. With an acceleration in recent decades: it has gone from 1.4 mm per year (1901-1990) to 3.7 mm per year (2006-2018), up to 4.5 mm per year (2023). The main managers are the dissolution of the glaciers and polar caps.
The danger for those who live along the coasts
The continuous dissolution of the glaciers exposes the population that lives along the coasts to an “existential danger”. About one billion people live less than 10 meters above sea level, and about 230 million to only one meter. Without adaptation policies, prudent estimates suggest that the raising of 20 centimeters of the sea by 2050 could cause losses of $ 1,000 billion per year due to floods in the 136 larger coastal cities.
The new analysis found that even if the emissions of fossil fuels were quickly reduced to achieve the aim of the and a half degree, the sea level would increase by 1 cm per year by the end of the century, faster than the speed with which the countries could build coastal defenses.
To get to these conclusions, the researchers have combined data from studies on “hot periods” up to 3 million years ago, observations on the dissolution of glaciers and on the rise in sea level in recent decades.