Climate change is a well-covered topic. While we have heard about the threat to polar bears and rising tides it appears that the risks are endless. Recently a study emerged about a tsunami that is likely to occur soon as a result of climate change. The tsunami will happen in Alaska and it threatens nearly 300,000 people.
In Alaska, there are a high number of glaciers. These amazing formations bring their own ecosystem and when they start to recede due to climate change they bring their own dangers. 100 km east of Anchorage lies Barry’s Arm fjord. Barry’s glacier runs into the fjord and between 2009 and 2015 scientists have noted that it has receded by 600 feet. The retreat of the glacier is put down to climate change as temperatures in some parts of Alaska are warming at twice the rate of the rest of the world.
The glacier supports mountains on either side and if it continues to decline the lack of support could cause a massive landslide to take place. The continued retreat of the glacier will cause this landslide to occur at some point. Scientists are unsure when it will take place but say that it could happen in the next year and it is likely to happen within the next 20 years. While the main cause will be climate change the landslide could be triggered now by anything like heavy rainfall, a particularly warm summer, or an increase in snowfall.
When the landslide happens the resulting tsunami will be devastating to the local area. While the glacier and surrounding area only attract around 500 people at a time, a mixture of hunters, tourists, and fishing crews, the tsunami will reach a lot further than that. Scientists estimate that the tsunami will reach 100 feet in height (the same height of the tsunami that devastated Thailand in 2004 and killed 170,000 people). The tsunami is expected to pose an extreme risk to anything with a 16 km zone. After this zone, it is expected to fall to around 30 feet and still pose a high risk. There are a number of towns in this second zone that will be impacted by the landslide and resulting tsunami. Experts believe that in total around 300,000 residents are put in some form of danger by the event that is likely to occur.
The community of Whittier (population of around 200 people) is most at risk and models suggest it will take 20 minutes from the moment that the landslide occurs for the tsunami to reach the community. This will likely not be enough time to get to higher ground for many. With that in mind, scientists are keeping a close eye on the glacier and the surrounding mountains to better understand any slight changes that occur. They hope that by continuing to investigate the mountain they will be able to predict the landslide in advance of it occurring. Of course, if you live in Whittier this may be the best sign you will ever get that it is time to move.
Alaska has seen several tsunamis as a result of glacier retreat. In general, this type of tsunami is the largest recorded. In Greenland, a much smaller landslide killed four people. Experts say the size of Barry’s Arm landslide will be much bigger and therefore much more threatening.
One leading scientist who published the warning letter about Barry’s Glacier says that in the past these types of events have been rare. However, the doctor warns that with the increase in climate change the likelihood of these events occurring also increases and that they may become part of the new normal.