Perth, Jan 24 (The Conversation) An underwater volcanic eruption around Tonga and the Hunga Tonga-Hunga Hapai Islands has caused tsunamis in countries around the Pacific and on 21 beaches in Peru. A horrific incident of disintegration took place.
The tsunami in Tonga caused waves about two meters high, making it difficult to measure sea level. At the same time, waves up to 15 meters high were seen on the western coast of Tonga Island, Aua and Hapai Islands. Volcanic eruptions can last for weeks or months, but it is difficult to predict when such a powerful volcanic eruption will occur now.
Most tsunamis are caused by earthquakes, but landslides or volcanic eruptions are responsible for about 15 percent of such disasters. Some of these reasons may also be related to each other. For example, earthquakes or volcanic activities are also involved behind tsunamis caused by landslides.
But does climate change play a role in this as well? With the rise in temperature on the earth, we are witnessing the disasters of storms and cyclones more often. Events such as melting of glaciers and rising of sea level come to the fore. However, climate change does not only affect the atmosphere and ocean, but also the surface of the earth.
Climate-related geological changes can increase events such as earthquakes and volcanic eruptions, resulting in an increased risk of tsunamis. This event can unfold in these five ways:
1. Sea level rise
If rates of greenhouse gas emissions remain high, the average global sea level is forecast to rise between 60 centimeters and 1.1 meters. Nearly two-thirds of the world’s more than five million cities are at risk.
With rising sea levels, the population living in coastal areas is not only at risk of floods caused by storms, but also the fear of tsunamis. A slight rise in sea level rapidly increases the risk of flooding and can lead to a tsunami.
For example, a 2018 study found that a tsunami-induced flood in Macau, China, was predicted to double the risk of flooding by just 50 centimeters of sea level rise. This means that even small tsunami disasters in the future can cause as much damage as large tsunamis today.
2. Landslide
Global increases in temperature increase the risk of landslides both underwater and on the surface, and this increases the risk of local tsunamis.
Melting of permafrost at high altitudes reduces soil stability and increases the risk of erosion and landslides. Earthquake-like events also come to the fore due to torrential rains.
Underwater landslides are prone to tsunamis.
3. Breaking of icebergs
The rate of melting of icebergs is increasing due to global warming. In this, large parts of the glacier melt and reach the sea. According to studies, large icebergs like the Thwaites Glacier in Antarctica are projected to break and melt in the next five to ten years. Similarly, the ice in Greenland is melting rapidly.
Existing research has mainly focused on the relationship between rising sea levels and melting glaciers, but the risk of tsunamis cannot be ignored.
4. Volcano eruption due to melting of icebergs
When the last ‘Ice Age’ ended about 12,000 years ago, melting ice saw a rapid increase in volcanic activity. Any link between climate change and the eruption of more volcanoes is not yet widely understood, but it can be linked to changes in pressure on the Earth’s surface, where melting ice would reduce its mass. Is.
If this correlation is taken into account for the current period of climate change and melting of ice in high altitudes, the risk of volcanic eruptions and associated tsunamis also increases.
5. Increase in the incidence of earthquakes
Climate change increases the incidence of earthquakes in many ways and also increases the risk of tsunamis.
Firstly, the melting of ice sheets increases the risk of earthquakes with reduced pressure on the Earth as the Earth’s surface vibrates to accommodate the reduced load.
In addition, the low air pressure area associated with storms is also a factor.
How can we be ready?
Factors in strengthening tsunami preparedness should include a range of strategies to mitigate the effects of climate change. This may include incorporating projected sea level rise into tsunami forecasting models and creating building codes for infrastructure in vulnerable coastal areas.
Researchers can add predictions of an increase in the incidence of earthquakes, landslides and volcanic eruptions to scientific models of the effects of climate change.
(The Conversation) Vaibhav Shahid
Shahid