Blue Ice & Depth Charges ~ Perito Moreno Glacier

14 March, 2018

I could barely contain my excitement as we boarded the Always Glaciers tour bus, anticipating our third national park, Los Glaciares National Park, and one of Argentina’s most visited destinations, the Perito Moreno Glacier. Rain clouds teased overhead but I was remaining cautiously optimistic that the Argentina rain gods would be kinder to us. Weather is so fickle here in Patagonia, so no use expending negative energy worrying about that which I couldn’t control.

El Calafate is famous as the base for visiting this glacier and the southern sector of Los Glaciares National Park, the largest national park in Argentina. The park has been named a UNESCO World Heritage Site, has 47 large glaciers being fed by a giant ice cap in the Andes, and 30% of its mass is covered by ice. This is the world’s 4th-largest ice cap, excluding Antarctica, Iceland, and Greenland.

The sky cleared as we paid our entrance fee to the park. I was encouraged as I had read that Perito Moreno tends to be more active in sunny weather. We were hoping to experience calvings off the face of this massive beauty.

There are several ways to see this gal – from her many boardwalks, taking a one-hour boat ride along part of her stunningly blue face, or trekking across. Try as I might before our arrival, I could not convince any of the tour companies to allow Terry to trek on the ice, their age limit being 65, and no exceptions due to the insurance they carried. 😦 We opted to stay on the boardwalks as we felt our chances of seeing calvings might be greater.

Not the largest glacier in the park but the one with star quality, Perito Moreno upstages twice-as-long Glacier Upsala, who has picked up much more debris during her advance and is not the brilliant blue that characterizes Perito Moreno.

Unsullied Perito Moreno, a jagged mass of crevasses and knife-edged seracs, is one of only two advancing glaciers in all of South America, crawling forward at a rate of ~ 2 meters per day. Most of the massive glaciers cloaking the spine of the Patagonian Andes are retreating in response to global warming, according to Andrés Rivera, a Chilean glaciologist, all except for Perito Moreno and Pio XI in Chile.  Perito Moreno, at  30 kilometers long and 5 kilometers wide, overshadows all else, sitting in the largest of Argentina’s lakes, Lago Argentino. Over 50% of her bulk sits below the sea, for a total combined height of ~ 170 meters.

Over millennia, untold numbers of storms have deposited countless meters of snow, compressing this glacier into what we see today. As the ice pushes across the channel of Lago Argentino, a massive dyke of ice cuts off the Brazo Rico arm of the lake from the main body. The water pressure builds until the natural dam can no longer bear the weight, resulting in an explosion of ice and frigid water that rushes into the lake’s main glacial trough, flooding everything in its path, including El Calafate. This phenomenon has occurred fifteen times during the 20th century, then from 1988 until March 2004, silence.

There was an arch over this section until two days before our visit.

On March 14, 2004, the dam gave way, releasing an avalanche of water and ice, a fitting metaphor for the flood of tourists who invaded El Calafate in hopes of seeing this event. It is said that those lucky enough to witness such a spectacle have found it to be one of nature’s most awesome sights. The last event of this type occurred just two days before our visit. Although this would have been the ultimate, the 14-meter wall of water that descended upon El Calafate is the reason the Laguna Nimez Bird Sanctuary was closed due to flooding. 😦

As if acknowledging our sadness at the loss of seeing all those feathered charmers, Perito Moreno stepped up and performed mightily the day of our visit. From our boardwalk perch, we listened for the sound of the glacier calving. Once you hear a sound that resembles a small cannon, get prepared for the show. Camera should be on-the-ready or you’ll miss blocks of ice, weighing hundreds of tons, detonating off the glacier’s 74-meter face, crashing into what has been dubbed “Iceberg Channel” below. These frozen depth-charges trumpet the forming of a new iceberg.

And the walls came tumbling down! Terry captured this on video. 🙂

These massive calvings occur several times daily and we were fortunate to see several during our few hours on the viewing platforms. Imagine pieces of a 24-story building being blasted away by a small cannon and this is the sound you hear. Terry got some great video footage, but internet will not allow me to upload it at this time. I see another Perito Moreno post in my future. 🙂