The Pio XI Glacier is the largest glacier in the Patagonia Icefield and it is as big as Santiago. he color of the blue ice was so much more vibrant than I imagined it would be. The glacier is approximately 1265 square kilometers. It is estimated to grow between 2 and 50 meters per day. An Article on sciencedirect.com states that between 1945-1995 it advanced 10 km. It was certainly a sight to behold. If you look into the distance in this photograph, you can see our cruise ship which looks tiny though it was not.
How then, can this glacier ( and the Perito Moreno Glacier in Argentina) be advancing when the planet is experiencing climate change? One theory is that the warmer ocean temperatures are causing more ice to melt and that this increases moisture levels that are sucked up into the atmosphere, which becomes snow is cooler areas like this. Another theory has to do with the equilibrium line above which glaciers grow from accumulated snow and below which they melt due to warmer temperatures. It is possible that the steepness of the mountains mean there is less below the equilibrium line. (http://news.nationalgeographic.com/news/2009/06/090622-glaciers-growing.html). No one really knows for sure. Overall, more ice is certainly being lost in the region. Most of the glaciers in Darwin's time came right down to the waters edge, while today many are hanging.
The three photographs below show the succession of the glacier calving while I was standing on a sandy beach in front of it. In the first image, a little is starting to break free, then you can see a huge chunk moving. It was so powerful I could feel the ground shake. The third image was taken right as our expedition leader was urgently yelling run, since I giant wave was created that chased us back towards the water. Fortunately, it stopped in time.
Calving Glacier Just Before we Ran
After the wave retreated, I walked back to see what the scene looked like. The two images below show a before and after of what the water in front of the arch looked like around the time of the collapse. I was amazed how many huge blocks of ice could be deposited.
Below are some additional photographs of this magnificent glacier. The sand patterns created as the glacier picks up the earth as it travels were fascinating to study up close. Nature is an incredible artist.
The fissures were also interesting to observe and made me ponder the internal dynamics of water as it contracts and expands.
The relationship between the rocks and ice is complex. Some places evidence of ground up rocks is visible in the coloration of the glacier, while in other areas rocks are deposited on sandy beaches. As we were leaving to get into the zodiac, I noticed how many different types and shapes of rocks there were and even noticed there was a muscle shell. The geologist on board spotted muscle and other shells in a different area and concluded this must have been an inland sea at one time.
Not all the ice is gigantic and imposing. Earlier, when I was kayaking, I spotted this beautiful piece on a floe in the water that glistened like a diamond.
Looking back on the glacier and the mountains as we departed, I was struck by how much the frequent weather systems in Patagonia must contribute to the formation of the glacier. This is no doubt why many are purchasing land with glaciers to ensure they will have rights to water as the world runs out, though private ownership of this precious and life sustaining resource required by all seems very problematic to me.
We made one final stop before boarding the cruise ship, to see if we could locate a rufus chested dotterel. We were lucky enough to spot this delicate little bird on a rock formation that complimented his beautiful coloration.