Are sinkholes becoming a bigger threat due to climate change? Experts warn that extreme weather events could make sinkholes more frequent and prevalent across Australia. But here's where it gets controversial: while natural causes like chemical weathering and water erosion play a role, human-induced climate change may be a significant contributing factor.
Sinkholes typically form in areas underlain by limestone or carbonate rocks, which can concave due to chemical weathering. Water is a key culprit, eroding bedrock over time and creating caverns. As temperatures rise and rainfall patterns shift due to climate change, these processes can accelerate, increasing the risk of sinkholes.
Research has found evidence linking sinkholes to climate change, including droughts and floods. Heavy rainfall and surface flooding can trigger the collapse of normally stable cavities and erode soil to form new 'subterranean voids'. Rising water tables, driven by increased rainfall and storm frequency, may further destabilize the ground.
Heatwaves and drought can also contribute to sinkholes. In fact, studies have shown that sinkhole frequency in karst environments of northeast Spain increases during droughts. Countries like China and Iran have karstic landscapes, which are at high risk of sinkholes. In China alone, there is around 600,000km² of ground that could collapse.
Some metropolitan areas in Australia may be under threat of sinkholes developing suddenly due to plumbing issues or movement weakening the ground above old mine shafts. Business development manager at Rectify Group, Phil Irwin, warns that people have no idea of the extent of the risk. There could be countless undocumented mine shafts that authorities do not know about.
So, what are the early warning signs of a sinkhole? Keep an eye out for structural issues like cracks in walls and floors, or doors and windows that don't close properly. On the ground, look for buried items becoming visible, small ponds forming, depressions or slumping trees and fences.
How do you get rid of sinkholes? Irwin recommends resin injection, which involves stabilizing the ground by injecting expanding polyurethane resin into the soil through small holes. Bigger sinkholes, such as collapsed mine shafts, can usually be fixed by pumping cellular concrete into the cavity.
But here's the part most people miss: while natural causes are significant, human-induced climate change may be a major contributing factor to the increasing frequency and prevalence of sinkholes. So, what do you think? Do you agree or disagree with this interpretation? Share your thoughts in the comments below!
