Dark clouds hang dramatically in the sky, contrasting with soaring white cliffs streaked with deep blue and rising high above a turquoise lake. The smell of ice hangs in the air, as does the creaking, rolling sound of ice on the move. Occasionally that sound rises to a crashing boom as huge chunks break off and hit the lake's surface.
This is Argentina's Perito Moreno glacier, remarkable both because it is the world's third largest source of freshwater, and because — despite global warming — it is still growing. One of 48 glaciers fed by the Southern Patagonian Ice Field, Perito Moreno is currently about 197 feet (60 m) high and 3 miles (5 km) wide.
Commenting on the glacier's continued growth, Andres Rivera, a glacialist from the Center for Scientific Studies in Valdivia, Chile, says, "[W]e're not sure why this happens but not all glaciers respond equally to climate change."
This continued growth is especially perplexing in light of what is happening to most of the other Andean glaciers (and indeed glaciers worldwide) that are melting at increasing rates. Scientists have also reported that ice-loss in the Patagonian region is ten times the long-term average.
Despite continually having giant icebergs carved out from its midst, the Perito Moreno manages to keep up its production of new ice. The ice river is constantly growing and moving, changing its shape and the shape of the land around it. This may also be due to warming, however. A warmer climate generally means more rainfall, which can actually increase a glacier's size.
The expanding glacier slowly but steadily creeps over the deep lake (Lake Argentino) until it effectively cuts it in two. The water on one side of the lake then builds up with nowhere to go. Eventually the increasing pressure from the extra water ruptures the ice, often in a spectacular fashion. One lucky park ranger who has witnessed this rupture twice described it as being like “a massive building falling of [a] sudden.”
The first rupturing of the ice by water pressure occurred in 1917. The burst was so strong at that time that it washed away a nearby ancient forest of beech trees. Since then the ice ruptures about every four to five years, although it is far from regular.
The last time the water forced its way through the glacier was in March 2012. Many tourists who were lucky to be there at the time were treated to the awesome sight of giant chunks of ice breaking off and tumbling into the lake. Talk about being at the right place at the right time.
The Patagonian ice cap that the Perito Moreno glacier stems from is enormous. It resides on the border of Chile and Argentina and covers an area of 600,000 hectares. The Argentinian part of this area is home to 356 glaciers, and out of these Perito Moreno is the most well known and most visited by tourists. In fact, it's pretty safe to say that it’s the most famous glacier in South America!
Like other glaciers in this part of the world, the Perito Moreno is the product of falling snow. In the freezing temperatures of the Andes, the snow builds up faster than it can melt. This snow creates pressure and weight on the snow beneath it, crushing it into ice and gradually forcing it down the mountain as a frozen river.
The National Park Los Glaciares, which surrounds the Perito Moreno glacier, was made a UNESCO World Heritage site in 1981. The glacier itself was recently nominated to be declared one of the seven natural wonders of the world, but missed out in the end. We think that's a bit of a shame; it sure looks like a wonder to us!
Lake Argentino, which the Perito Moreno glacier slides into, has its own claim to fame. Not only is it the largest lake in Argentina but it is also at least 15,000 years old! The lake runs into the Santa Cruz river, which itself empties into the Atlantic Ocean.
On overcast days the lake appears a grey color with an almost satin sheen. The water is choppy from newly created icebergs dropping off the calving glacier. Above the waterline the ice is bright white, changing to a deep blue under the lake. Oxygen that has been trapped in the snow is responsible for the blue streaks in the ice — a hue that only adds to the stunning beauty of the glacier.
It's clear from these photographs why the Perito Moreno glacier is one of the most visited sights in the country, with tourists both domestic and foreign flocking to marvel at its beauty. In addition to the spectacular glacier itself, people come to enjoy the surrounding national park, which is full of breathtaking lakes, forests and wildlife. Yet of course, the prime attraction is the towering, moving wall of ice!
If looking at the awesome sight of the glacier isn't enough for visitors, there's also the opportunity to go trekking on the ice itself. This way they can see up close the many ruptures and crevices in the ice, as well as the lagoons formed from meltwater — which is pure enough to drink.
For those not so keen on walking, there is always the option of sailing on the lake. This way visitors can get close enough to the ice cliffs to truly appreciate their height and the caverns carved into them... as long as they stay out of the way of falling icebergs!
However you look at it, the Perito Moreno glacier is an astoundingly beautiful natural wonder. And since it is growing, it is one we won't have to worry about losing any time soon.
We'd like to thank photographer Jakub Polomski for sharing his amazing pictures with us for this story. If you would like to contact him or see more of his work, you can do so at his website.