American Alpine Jounrna and Accidents in North American Climbing

The Front Lines of Climate Change, Mountaineers are the World's Witnesses to Glacial Decline

  • Feature Article
  • Climb Year:
  • Publication Year: 2007

The Front Lines of Climate Change

Mountaineers are the world’s witnesses to glacial decline.

Joe Stock

Thirty miles into the Neacolas, clouds spread over the Blockade Glacier and reduced our visibility to zero. We groped along in the murk, making slow progress toward a series of passes that would get us to Glacier Fork. A rock outcrop appeared just ahead of us, even though our altimeters still placed us far out in the middle of the glacier. Annoyed, we rechecked the altimeters, compared them to the GPS reading, and passed around the 1958 1:63,360-scale USGS map. Was our navigation that far off?

Dylan Taylor, Andrew Wexler, and I were aiming for Lake Clark and a first ski traverse of the entire Neacola Mountains in Alaska. After endless crosschecking of our tools, we isolated

the source of our confusion: a consistent difference between the altitude shown by our altimeters and the 1958 map altitude. Since the map was made 48 years earlier, the glacier had lost over 100 feet of altitude. The rock outcrop was shown on the map, but, based on our altitude, we thought we were still a couple of miles away from it.

Mountaineers and alpine climbers frequently encounter the effects of climate change. Not all the changes are negative: In the Neacolas, shrinking glaciers made ski touring easier. With less snow surviving the summer months, the glacial conveyor belt has slowed and fewer crevasses form. In many places, however, melting glaciers means harder or more dangerous climbs. Many approaches to alpine climbs now are moraine bashes instead of easy glacier walks, and climbing up and down moraine walls is sometimes the most dangerous part of a trip. Blocks of seasonal snow cascade off glacier-polished slabs. Rocks previously frozen for hundreds of years plunge toward our flimsy helmets.

Classic routes are gone—at least in their old prime seasons. The Black Ice Couloir on the Grand Teton is a smear of dirt by August. The Diamond Ice Couloir on Mt. Kenya depends on rare melt-freeze cycles to form. The legendary White Spider on the Eiger must be climbed in the old “off season.” Perhaps only a generation will still see the snows of Kilimanjaro. The glaciers of Montana, Wyoming, Colorado, and California are hiding under piles of moraine. Remaining ice faces are often composed of unpleasantly hard ice above gaping bergschrunds.

Most Americans hear a lot about climate change, but their conversation on the subject may be spurred only by a heat wave or a balmy winter; their interest soon dies and they go on with their lives. The situation is different for those of us who play and work on glaciers. We have climate change shoved in our faces on every trip.

Glaciers are products of climate and are sensitive to changes in weather. By looking at a glacier and its surrounding basin, we can see the climatic trend. Large valley glaciers, like the Kahiltna Glacier on Denali, respond to climatic shifts in 100 to 200 years. Because of their length—the Kahiltna is 45 miles long—it takes at least 100 years before warming or a lower precipitation trend causes a measurable negative mass balance, or net ice loss. On the other hand, small mountain glaciers, like those in the Cascades, are more responsive to climate. Within a couple of decades, changes in weather show up as negative mass balance.

In September 2006, I guided the Easton Glacier on Mt. Baker in Washington; this glacier is climbed by hundreds each year, and has a serious negative mass balance. Within 15 minutes of seeing the Easton, my clients were asking about climate change. The glacier’s illness was obvious. Ground moraine coated the valley floor where the glacier had flowed less than 50 years ago. Along the glacier margins we saw bathtub rings where the glacier once had scoured the rock and since has melted down. These trimlines now frame the sides of most modern glaciers. Several kilometers up the valley, we saw the withering end of the glacier. As if wheelchair-accessible, the snout was a smooth ramp of dirty ice instead of the vertical or bulbous front typical of a healthy glacier. Higher, bare ice stretched up the mountain, with only the top quarter of the glacier covered in snow. Near the top I saw the dividing line between the old snow (firn) and new snow from the previous winter. This line, known as the equilibrium line

altitude, or ELA, should be only about halfway up a glacier if the glacier is to survive. Input must equal output.

Not all glaciers are shrinking. The Taku Glacier near Juneau is a 57-mile-long, 261-square-mile beast that has been fattening along its full length for over 30 years. The warming climate has shifted its accumulation area into the zone ideal for maximum snowfall. Forests are still being crushed by the Taku’s advancing front. However, virtually all of the rest of North America’s glaciers are not enjoying the same benefits.

Any scientific debate about global warming

ended quickly. Global warming is fact—the temperature has been rising since the Little Ice Age ended 150 years ago. The debate has been to what degree humans are involved. With the report by the Intergovernmental Panel on Climate Change released in March 2007, that debate is now over. Scientists now agree with 90 percent certainty that the majority of the average global temperature increase in recent decades can be attributed to human causes. Carbon emissions are to blame. We know from polar ice cores that temperature follows atmospheric carbon dioxide level, and carbon dioxide has risen dramatically above pre-industrial levels.

Although the tide of public opinion seems to be turning and action to reduce carbon dioxide emissions now seems more likely than it did a decade ago, pressure must be maintained on policymakers to take speedy and effective action if the trend of shrinking glaciers is to be halted. With our unique understanding of glaciers based on years of climbing and camping on them, mountaineers can influence people through our first-hand accounts of what we know about global warming. It is our responsibility to share our experiences in order to help save the mountain environment that we love.

Sharing your data, photos, and stories is the key. Nonclimbers want to hear news from the mountains. Tell your stories. Blow up your photos. Write a story for your local paper. You don’t have to be a scientist. Just tell them what you see. I include a five-minute section on climate change in my Alaska ski mountaineering slide show that is seen by hundreds each year.

While traipsing around the mountains, document what you see. Take photos of the end of glaciers showing the surrounding rock outcrops for reference points, and try to do this each year for comparison. Take photos of glaciers from vantage points that show the complete length of the ice. (Try taking your photos in late summer when most of the seasonal snow has melted.) Then compare the glacier to the map and to similar photos taken years earlier. If you don’t have old photos, take a macro photo of the area on a map, with pointers showing the before and after locations of the glacier’s terminus.

Glaciers lose most of their mass through thinning, and an easy way to measure this ice loss is by taking GPS elevations to compare with your USGS 1:24,000 or 1:63,360-scale maps. Handheld GPS units are not very accurate, but even approximate data is better than none. Using this technique, I found average glacier elevation loss of 70 feet over 10 locations across the Neacola Mountains. Keith Daellenbach measured an average elevation loss of 33 feet across

the Juneau Icefield, an area that includes the Taku Glacier, the United States’ healthiest glacier. These very simple data sets are great for slide shows and kids’ science classes.

Another way to measure ice loss is to take a GPS waypoint at the glacier terminus. Then compare that location to the map you’re using. I recently compared my April 2007 GPS reading of the Eklutna Glacier terminus near Anchorage to the 1994 USGS map and discovered that the Eklutna terminus had retreated an entire mile in this 13-year period.

Mountain guides have a unique opportunity to share the message about climate change with others, especially in talking with clients during trips and in presentations about our adventures to the public. Teaching others about climate change is an important part of your job. Your clients are interested and respect your knowledge. Be prepared to answer their questions.

As mountaineers, we also contribute to climate change, and we have a responsi

bility to mitigate our impacts. Our biggest negative contribution occurs while getting into the hills. We burn hundreds of gallons of gas each year, and this, in turn, sends hundreds of pounds of carbon into the atmosphere. Traveling to and from a recent Tordrillo ski traverse, for example, we flew 450 total miles in a Cessna airplane, burning over 100 gallons of gas. To help offset those greenhouse gas emissions, we purchased Denali Green Tags ( The money we spent to purchase these tags goes toward developing wind energy, arguably the cleanest renewable energy available.

To promote Green Tags among climbers, a group of us in Anchorage is working on an initiative called Climb Green ( We aim to have the cost of Green Tags incorporated into one’s ticket price to fly into Alaskan mountains. For example, when booking a ticket with an air taxi to fly into the Ruth Gorge, Denali Green Tags will be included in the ticket cost.

Glaciers can’t just grab a thicker blanket of snow from the closet, and we can’t grab another planet. Glaciers are pointing their thawing fingers right at us mountaineers. Let’s step up and be ambassadors for the mountains.

A Note About the Author:

Joe Stock works as a mountain guide, hydrologist, writer, and photographer. He lives in Anchorage with his wife, Cathy.

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