The moisture that seeps in between cracks in mountain rock can freeze and melt multiple times. As the freezing/melting process goes on, geologists say eventually the melting contributes to falling rock and dislodged boulders. While this is seen as a danger to rock climbers, experts seem to think there is a lot more to rockslides as it relates to climate change.
According to Australian geography expert, Roy Sidle, geologists have always understood that while many factors can cause rock falls, such as erosion, the underlying types of rock, human disturbance, and the freezing/melting cycle are the primary reasons for falling rocks. Now experts are looking at a paper published in 2016 in Nature Geosciences that is giving them more insight into the cause of rock falls. The report shows that data collected over a three-year span, demonstrates that a greater number of rock falls didn’t happen on days when a freeze and thaw occurred, but when sunny, hot days were dominant.
Furthermore, it was discovered that on those hot days, the rock heats up, slightly expanding and then at night, as temperatures drop, the rock cools and goes back to its original state. With current rising temperature trends and the increasing frequency of hotter than average days caused by climate change, this cycle of expansion/contraction causes small cracks and weaknesses in the rock to develop at a greater rate. As the size and quantity of weak points in the rock grow, a greater number of rock falls are threatening the safety of climbers.
For years the factors that were believed to cause rock falls were mostly out of the public’s hands, but now with such a link between rising temperatures and these natural disasters, it’s easy to see how climate change and rock climbing are related. If the future safety of climbers is to improve and these natural disasters are to be avoided, addressing climate change has to be a priority.