Volcanic ash has the potential to remove harmful gases from the atmosphere more cheaply, simply and less invasively than other techniques. Scientists researched the process by spreading volcanic ash on the ocean floor.
A team from the University of Southampton’s School of Ocean and Earth Science has modelled the impact of spreading volcanic ash from a ship to an area of ocean floor to help amplify natural processes which lock away CO2 in the seabed, explains a statement.
They found the technique has the potential to be cheaper, technologically simpler and less invasive than other techniques to remove harmful gases.
Most volcanoes lie close to the oceans, and every year millions of tonnes of volcanic ash falls into them and settles to the seafloor. Once there, it increases carbon storage in marine sediments and reduces atmospheric CO2 levels. This is important because the oceans are the greatest sink of manmade CO2 on Earth.
The scientists modelled the effect of distributing volcanic ash from a ship to an area of ocean. The results suggest that this method could sequester as much as 2300 tonnes of CO2 per 50,000 tonnes of ash delivered for a cost of $50 per tonne of CO2 sequestered – much cheaper than most other methods.
In addition, the approach is simply an augmentation of a naturally occurring process, it does not involve expensive technology and it does not require repurposing valuable agricultural land.
The scientists say further research is needed though to test the efficiency of enhanced ash deposition in the oceans and to make sure there are no unforeseen side effects, but initial indications suggest that it could be applied easily and cheaply in many areas of the world.
Image credit: BelaMarie via Pixabay