Tuesday, December 19, 2017

How Air Pollution Causes Landslides

Air pollution in Asia has reach severe proportions. Lung and cardiac diseases are exacerbated, if not caused, by smog from heavy traffic and burning coal.  Researchers say that landslides can even result from air pollution.

 Cracks appear in rock formations over time due to differences in daily temperatures.  These formations are further destabilized by water and plant roots.  Oftentimes heavy rains and/or an earthquake is all that is needed to cause a landslide

Pollutants are released into the atmosphere and their chemicals react with rain water forming sulfuric and nitric acid.  The normal pH of rainwater is 5.  The acids in the polluted rainwater lower the pH to 4.3.  This small difference, say geologists, is enough to have an effect on water-soluble rocks.  Limestone and shale are particularly vulnerable to the lower pH of the acid rain  as it dissolves the calcite, which holds the shale together.

The acid rain also has an effect on the cracked limestone as it provides oxygen and food to the microorganisms which live in the rocks.  The layers of rocks become slippery because of the loss of organic material and large amounts of limestone slip down the slope.

Risky areas for future landslides are being studied by researchers in hopes that this knowledge would help to recognize these risk zones.  This could also demonstrate the need for investing in clean energy.