2025 is the International Year of Glaciers’ Preservation (IYGP2025) by the United Nations General Assembly to “highlight the importance of glaciers and ensure that those relying on them, and those affected by cryospheric processes, receive the necessary hydrological, meteorological, and climate services. These efforts underscore the critical role mountain regions play as a key source of global freshwater and ecosystem services”.
A glacier associated with year-round high-altitude, is a mass of snow or ice that moves downhill. Glaciers are melting rapidly and disappearing around the world with the extremes of climate change. This is bringing dramatic changes to the earth’s topography, plants, animals and water supply, dependent on what was once a gradual process of slow melting ice into cold water runoff. Large glacial masses such as Antarctica and Greenland, which are really mostly ice, are melting and contributing to global sea level rise.
In Peru, a farmer who has lost his livelihood due to floods from too rapidly melting glaciers is actually suing the German multinational energy company RWE showing how these impacts are global and need a response.
When I was in college in the Bay Area many years ago, there was a multidisciplinary class called Mountain Studies which included extracurricular rock climbing with what turned out to be challenging local steep rocks of the East Bay. Challenging because I had a basic fear of heights, but I’ve learned to get over it. The first time I had to jump backwards, repelling with ropes off a steep rock, was a great experience but what I really missed was the summer field trip to the Sierra Nevada for a glacier climb, which required ice pics and crampons for ice.
That was in the early 1970s and at that time California had approximately 50% less glaciers in the three higher mountain ranges, the High Sierra, the Trinity Alps and the Southern Cascade mountains than they did in the John Muir era. By 2021 Sierra Nevada glaciers had lost an average of 75% of their mass while some in the Trinity Alps had disappeared completely. With the extreme dryness of climate change (I don’t use the word drought because droughts end) we continue to have the driest and the warmest winters with far less snow and more rain causing further degradation of the glaciers.
Glaciers formed the unique topography of Yosemite and still provide cold water runoff. Of the 20 named glaciers in California, 13 are in Yosemite including Lyell and Maclure Glaciers in the headwaters of the Tuolumne River. The less visited Tuolumne River Canyon shows the power of glaciers to scour out rock and form what is often called the Little Yosemite valley – the Hetch Hetchy valley. Unfortunately, it is mostly underwater from the O’Shaughnessy dam, which provides water for San Francisco and the Peninsula. It is worth a visit to see the glaciers especially in the hot summer months when the high altitude provides some relief. There is a movement to Restore Hetch Hetchy Valley but that is another story for another day.
To the north, the volcanic 14,162 foot Mount Shasta, which is part of the Southern Cascade Mountain range, are the Whitney Glacier, which is the longest and California’s only valley glacier, and the Hotlum, which is the largest. While Mt. Shasta has snow year around, a new climate change pattern seems to be emerging with an early very wet December but then completely or very dry January, like this last year (2024) and the 2021-2022 winter. These changing baselines have led to less snowpack and moisture with less glacier build up over time.
Through the eons of time and the ice ages there were once glaciers in the San Bernardino mountains, but now the southernmost glacier in North America is the Palades glacier in the John Muir wilderness. It is fitting because John Muir “discovered”, named and hiked on many California glaciers in his time.
While there are many glaciers in the Sierra Nevada mountain range, they are shrinking and over time disappearing. Maybe it is time for me to get out my hiking poles and ice gear and go experience California glaciers while they are still here.
Conner Everts is a long time water activist and the facilitator of the Environmental Water Caucus