A glacier disappears

The Rhône Glacier in the Swiss Alps is easy to reach by car. You can even go inside and walk through an ice grotto carved into the glacier. But you should hurry, because this glacier will soon be gone. The Rhône Glacier is in the canton of Valais. It is still about eight kilometers long, two kilometers wide, and up to 350 meters thick. It reaches an elevation of 3,620 meters, while its lowest point, the glacier tongue, is about 2,200 meters above sea level. A small lake has formed in front of the glacier tongue in recent years. The River Rhône, known as the Rotten in Switzerland, rises in this lake.

The Rhône flows through the Valais and into Lake Geneva, then into France towards the city of Lyon. It is 812 kilometres long in total, 545 kilometres of which lie in France. It flows into the Mediterranean near Marseille. The Rhône’s tributaries include the Saône, the Doubs and the Isère.

The Rhône Glacier used to be much larger than it is today. In old pictures, it reaches far down into the valley carved by the Rhône. But like all glaciers on Earth, the Rhône Glacier has been shrinking for some time and will probably disappear completely soon. There’s a human-made reason for this.

For about 200 years, we have been burning a lot of wood, coal, oil, lignite and natural gas. We use these fuels to generate electricity, heat our homes and power cars, ships and planes. Burning them releases gases, especially carbon dioxide, methane and nitrogen oxides. These gases mix with the air and rise into the atmosphere.

These gases let sunlight through, but trap heat radiating from the Earth. As a result, the average temperature in the lower layers of the atmosphere rises slowly but steadily. This process is called the greenhouse effect. In summer, a lot of glacial ice has always melted. But in winter, frost and snowfall would create new ice, so the glaciers kept their size or sometimes even grew. However, if they now lose more mass in summer than they gain back in winter, they will get smaller and smaller.

The Rhône Glacier has been surveyed regularly for about 150 years. During this time, there were only two short periods when the glacier expanded. In every other year, it retreated. Over the past 15 years, it has lost a metre in height each year. This process will accelerate further in the coming decades. By 2060, it will be about 2 metres lower each year; after that, the area it covers will shrink considerably. Scientists believe that by the end of the century, little will remain of this glacier, which formed thousands of years ago.