June 21. An equinox, the summer solstice, estival solstice or midsummer. It not overly important what term you use, it is the day whereby one of Earth’s poles has its maximum tilt toward the Sun. It happens twice yearly, once in each hemisphere (Northern and Southern). For the Alpine Glacier Project it forms a point whereby one can judge the onset of the summer ablation period with previous years. Something we’ve been doing for 50 years.
Today is June 21. “The longest day”. A day to enjoy the maximum amount of available daylight, but we are far from celebrating. Traditionally, summer and winter solstices helped mark the changing of the seasons. However, today’s meteorologists officially use temperature records instead to draw lines between the seasons. That said, this week alone, Yellowstone National Park is closed due to a 1 in 500 year flood event, whilst Iran soared to 52.2°C (in the shade!) – one of the highest pre-solstice temperature readings ever. Our changing climate could not be more real. Yesterday Mawsynram in India recorded 1003.6mm of rain in 24 hours, whilst Pensicola, USA set another new all-time record high temperature of 40.56°C. And so it goes on. Rainfall and temperature records broken frequently, globally.
Here in Switzerland, the changing climate is having what can only be described as a catastrophic impact on the mass balance of glaciers. Minimal winter snow cover (which protects the ice through reflecting the increasingly powerful radiation from the sun) quickly melted, increasingly high temperatures melt ice higher up the mountains. As a result what we see today is a stark image. Snow cover and ice melt akin to mid-August, not mid-June!
Scale is lost in the mountains, Gornergletscher was once 500m thick. But let’s contrast a few images…
To show the difference in snow cover at this time of year, here we have 18th June 2019 and 18th June 2022. Both taken from the Gornergrat looking toward Grentz and Gorner glaciers and the Monte Rosa Massif.
Let’s reflect and contrast 50 years looking from the Gornergrat toward the Theodulgletscher, which descends from the west side of the snowdomed capped Breithorn (4,164 meters). The picture on the left was taken in 1970, on the right in 2022. The loss of ice is significant, close to 1.2km of length loss with significant volumetric loss too.