Hello from Huaraz!

Back for my second season in the Cordillera Blanca. And none too soon it seems, as there has been significant glacial retreat even since I was last here 11 months ago.

Peru’s Cordillera Blanca is a tropical mountain range, making it especially vulnerable to the effects of a warming global climate. Whatever your political stance on the issue, it is impossible to deny that these glaciers are melting. Here’s just a few quick photo comparisons from the lower-elevation peaks around town:

Churup

Churup is a ~5,500 meter peak near town. The hike to Laguna Churup at the base of the peak’s West face is one of the most popular day hikes in the area. Brad Johnson’s 2003 guidebook, Classic Climbs of the Cordillera Blanca, contains a photo of the face and a route description. He describes two pitches of mixed rock and ice (~100 meters), the rest of the route on snow, and gives the route a grade of D+

That was Churup in the early 2000s. Note how far down the slabs the glacier reaches. Here is Churup today:

The above image should be a comparison where you can slide back and forth between the 2023 image to the 2024 image. It may not work on all browsers. Leave a comment if you’re having trouble with it. Those photos were taken 11 months apart – July 2023 to June 2024.

He reports bad climbing conditions on the face, with lots of dangerous loose rock. April 2024.

Huarapasca

Huarapasca is one of the few peaks in the Cordillera Blanca which you can complete in a day, car-to-car, from Huaraz. I climbed it last year (My 2023 trip report for Huarapasca). This year, the toe of the glacier has visibly receded, and it is now being climbed in the dead of night due to rock and icefall which begins as soon as the dawn rises. Last year we were rappelling down the ice shield at ~1 o’clock in the afternoon, and nothing was falling. This year, that’s a recipe for disaster. The below photos (another slide-to-compare) were taken only ten months apart.

Understand that these are only anecdotal reports. And these are lower-elevation peaks – the higher one will hold on a little longer. But it is shocking to see with your own eyes.

Glaciar Pastoruri

From the summit of Huarapasca, one can see the Pastoruri Glacier, one of Peru’s most famous, and a longstanding tourist attraction due to the easy access. That reputation won’t last though; it is vanishing fast, and is projected completely disappear within 10 years. To take this beyond my personal observations, I’m going to excerpt a little bit of scientific data from a Peruvian government report, by the Authoridad Nacional de Agua (National Water Authority) titled “Pastoruri: 40 Years of Glacial Studies.”

These maps show the location of the Cordillera Blanca within Peru, and the exact location of the Pastoruri Glacier within the range. Huarapasca is the white area just to the north of the road leading to Pastoruri, for reference.

In this aerial diagram, you can see how far and how fast the edge of the Pastoruri glacier has been receding over the past two decades. Where it once used to be a complete glacier, it has now broken into four pieces. Much of the vanished ice surface has melted and formed a large lake at the base of the glacier.

There is much more in the complete report, including maps of the ice surface and graphs showing the decrease in glacier volume, year over year. The six conclusions of the report (as translated by me) are:

1. Pastoruri is an excellent demonstration of changes which are happening in the glacial ecosystem.
2. Our monitoring tools have evolved over the years, allowing for more accurate data today by using tools such as drones and surface-penetrating radar.
3. Between 1980 and 2019, the edge of the Pastoruri Glacier receded more than 600 meters (1970 feet), with the decay accelerating from 1995 on.
4. In the last 25 years, Pastoruri has lost 70% of it’s surface area. Additionally, it has been fragmenting: in 2008 it broke in two, in 2012 in 3, and in 2019 it separated into four pieces.
5. Between 2001 and 2019, the glacier discharged 27 million cubic meters of water into the local watershed, which was used for many productive projects and irrigation.
6. The glacier’s retreat has created the Laguna Pastoruri, a new source of fresh water. In 2017, this lake had a volume of 750,000 cubic meters of water.

Downstream Effects of Melting Glaciers

As addressed in the report above, the melting of the glacier has not been all negative. The large amount of water being released into the ecosystem has caused an agricultural boom in the hills above the Callejon de Huaylas (the valley in which Huaraz sits). The markets in Huaraz and Yungay are filled with delicious, cheap blueberries – a new delicacy. The desert is blooming in new ways.

Although the Pastoruri lake is not dangerous, glacier melt damming up in the moraines and subsequently bursting has been a problem in other areas of this mountain range. There is a long, sad history of natural disasters here caused, at least in part, by glacial phenomena.

Excerpt from “Yuraq Janka: A Guide to the Peruvian Andes” by John Ricker (1977):

From page 35, section titled “Catastrophic Glacial Events“:

The formation of new glacial lakes (pro-glacial lakes) and the expansion of preexisting lakes has been one of the most perilous consequences of the general glacial retreat (Track 1953, Fernandez 1957, Oppenheim, 1946). In the past, sudden drainage of moraine dammed lakes has resulted in the formation of aluviones: great flows of turbulent rock, sand, mud and water mixtures, which devastate the valleys below.

The cause of the rupture of the moraines has been attributed to weakening of the morainal dams through water infiltration. Other aluviones may have been triggered by ice avalanches off the glaciers and peaks which caused a wave to surge over the morainal dam, breaching it in the process.

More than 5,000 people in the city of Huaraz were killed during the rainy season in December 1941 as a result of a morainal dam giving way at Pallkagocha (ca 4400m).

The outburst of water soon picked up boulders and fine sediment from the stream bed, as well as from nearby older glacial-fluvial deposits. The aluvión then broke through the morainal dam of a second lake (ca 4000m) seven to eight kilometers downstream releasing yet more water, increasing the sediment load, and finally inundating part of Huaraz (ca 3050m) some fourteen kilometers further down stream (Oppenheim, 1946).

The chapter goes on, and there are many more examples of deadly alluviones in the region’s history. The most famous being the 1970 earthquake and subsequent alluvion from the flanks of Huascaran, which completely buried the town of Yungay, killing 25,000 people.

For most of us, climate change is nothing more than a graph or an abstract arena in which to earn political points. Here, it is happening daily. It has been happening daily for a long, long time.

Looking to the Future

In 2020, Peru announced that the country had lost more than 50% of its glaciers in the past 50 years. What will the next 50 bring? I can’t say, on the grand scale. But I can say that if things continue on this track, I doubt there will be much ice and mountain climbing happening here. The range is already becoming more dangerous than it used to be.

Nothing I didn’t know, but still, a sad realization to start the season. We’ll be hanging around for the next month+ climbing, feel free to reach out if you’ll be passing through the area. Ice and mixed leads the itinerary, while it’s still around.