‘As the Earth warms by 2 degrees, Greenland’s ice sheet will collapse’

The melting of the Greenland ice sheet will cause an inevitable sea level rise of at least 27 cm worldwide. According to a study in the scientific journal The nature of climate change. Glaciologist Philip Hebrechts (VUB) notes his seriousness.

We have historically had a warm summer. Has this also had an effect in Greenland?

“It’s not about one summer. The warm summer is only responsible for an increase of up to 1 millimeter. What matters is the sum of the hot summer. Year after year, the ice caps are melting and we are seeing sea level rise.”

“The warmer it gets, the greater the imbalance between melting and snowfall. Currently, the ice sheet is melting more than the snow is accumulating. This may seem paradoxical, but to restore the balance, the ice sheet must lose more mass. Then the ice sheet is smaller and this compensates for Snowfall Decreased.Jason Books’ Study temper nature It is based on data from the last twenty years. If these temperatures remain unchanged, the melting of the ice sheet will lead to a height of at least 27 cm.”

Why is this increase inevitable now?

“The 27 centimeters are necessary to find a new equilibrium. We are getting closer and closer to the so-called tipping point. The imbalance is getting bigger and bigger, and if it continues to warm up, 27 centimeters won’t be able to provide a new equilibrium. As the Earth warms by about two degrees, the ice sheet is doomed. with annihilation and it will disappear irreversibly and irreversibly. Then our height will rise by about 7.5 meters in a few thousand years, depending on the temperature.”

What about 27 cm? What kind of time period are we talking about?

We cannot set a specific date for this. This is only possible on the basis of calculations using ice cover and climate models. This way we know that by the end of this century we will have an increase of 5 to 15 cm.”

Can we extend this situation to the Antarctic ice sheet?

“It is still very cold in Antarctica. At the moment, there is not even surface thaw, not even during the summer. In theory, it is possible that the Antarctic ice sheet will also disappear. However, for the sake of that, We need a global warming of more than 10 degrees and that is far beyond the 2 degree warming that will cause the Greenland ice sheet to disappear.”

Could packing ice caps help curb this rise?

“In principle yes, but in practice this is not possible. Filling a glacier is difficult enough. The surface of the ice sheet is very large, so let’s start.

There is only one real measure, and that is the fight against global warming. This is only possible by reducing our emissions to zero worldwide as quickly as possible. Not for less, but for zero. For that we need bold politics and brave politicians.”

However, sea level rise is not only due to melting ice sheets.

“Right. The main factor for the current rise is the expansion of sea water. When you heat the water, its density decreases and the water expands. The same is happening in the ocean. Today’s sea level rises about 4 millimeters per year. By the end of this century, we will rise from 30 cm to one meter”.

What is the effect of that increase?

A large part of the world’s population lives on the coasts and there are many cities that rise one or two meters above sea level. At some point we will have to evacuate large areas. Sea level rise is largely far-reaching, but we cannot stop it in the short term. The sea level will rise for a very long time, but preferably not too long and preferably not too much.” (EVP)