Five ways climate change increases tsunami threat, including collapsing glaciers and sea level rise

Hunga Tonga Ha’apai, an underwater volcano in Tonga that erupted massively, triggered an alarm. tsunamiIt reached countries all along the Pacific Rim, even causing havoc in some countries. Katastrophic oil spillageAlong 21 beaches in Peru

Tonga saw waves that were about 2 metres high before the sea-level gauge failed. Waves of up to 15m hit the west coasts of Tongatapu Islands, ‘Eua, and Ha’apai Islands. Volcanic activity could continue for weeks or months, but it’s hard to predict if or when there’ll be another such powerful eruption.

Although tsunamis are most often caused by earthquakes and other natural disasters, a majority of them are caused by tsunamis. significant percentageAbout 15% of these are caused by volcanoes or landslides. Some of these may be interlinked – for example, landslide tsunamis are often triggered by earthquakes or volcanic eruptions.

But does Climate ChangeAre you also a part of the solution? As the planet warms, we’re seeing more Intensive and frequentStorms and cyclones, melting glaciers and ice cap ice caps, and rising sea levels.
Climate change, however, doesn’t just affect the atmosphere and oceans, it affects the Earth’s crust as well.

Climate-linkedGeological changes can increase the likelihood of earthquakes or volcanic eruptions, which can in turn increase the risk of tsunamis. These are just five ways it can happen.

1. Sea level rise

If greenhouse gas emissions continue at high rates, the global average sea level will remain Promised to increaseBetween 60 cm and 1.1m Nearly two thirds of the world’s cities with populations over five million are at risk.

Rising sea levels make coastal communities more susceptible to flooding from storms and tsunamis. Even small rises in sea levels can significantly increase the frequency of flooding and intensity when a tsunami hits, as the tsunami can travel furtherinland.

For example: A 2018 studyIt was shown that a 50 centimetre increase in tsunami-induced flooding would double the frequency in Macau, China. This means that smaller tsunamis could in the future have the same effect as larger tsunamis.

2. Landslides

A warming climate can increase both the risk of sub- and aerial landslides and, consequently, the risk of local tsunamis.

The Permafrost melting(frozen soil) At high latitudes, soil stability decreases making it more vulnerable to erosion. Continue reading intense rainfallAs climate change makes storms more frequent, landslides can also be caused by them.

Tsunamis can occurOn impact when a landslide is introduced to the water or when water is moved underwater by a rapid landslide.

Continue reading:
Waves from the Tonga tsunami are still being felt in Australia – and even a 50cm surge could knock you off your feet

In general, tsunami waves generated from landslides or rock falls dissipate quickly and don’t travel as far as tsunamis generated from earthquakes, but they can still lead to huge waves locally.

In Alaska, the melting permafrost and glacial receding have exposed unstable slopes. This melting led to a landslide in 2015 that sent 180 million tonnes rock into a narrow fjord. A tsunami measuring 193m in height – one of the highest ever recorded worldwide.

Other areas that are at risk include northwest British ColumbiaCanada and Alaska’s Barry Arm, where there is Instabile mountain slopeThe Barry Glacier at the toe is susceptible to failure. Create a severe tsunamiIn the next 20 years.

3. Iceberg calving and collapsing of ice shelves

Global warming is increasing Rate of iceberg calving – when chunks of ice fall into the ocean.

Studies predict that large ice shelves like the Thwaites Glacier in Antarctica will form. Most likely, a collapseIn the next five to ten year. The Greenland Ice Sheet is also being monitored. Thinning and retreatingAlarmingly fast.

While much of the current research focus is on the sea level risk associated with melting and collapse of glaciers and ice sheets, there’s also a tsunami riskFrom the calving and breaking up process.

Wandering icebergs can trigger Submarine landslides and tsunamis thousands of kilometres from the iceberg’s original source, as they hit unstable sediments on the seafloor.

4. Volcanic activity due to ice melting

About 12,000 years ago, the last glacial period (“ice age”) ended and the melting ice triggered a dramatic Volcanic activity has increased.

The correlation between climate warming and more volcanic eruptions isn’t yet well constrained or understood. It could be related. Changes in stress to the Earth’s crust as the weight of ice is removed, and a phenomenon called “Isostatic rebound” – the long-term uplift of land in response to the removal of ice sheets.

If this correlation holds for the current period of climate warming and melting of ice in high latitudes, there’ll be an increased risk of volcanic eruptions and associated hazards, including tsunamis.

5. Increased earthquakes

Climate change can cause an increase in the frequency of earthquakes and increase the risk of tsunamis.

First, the weight and volume of ice sheets could be Suppressing earthquakes and fault movement. The isostatic rebound (land elevation) that occurs when ice melts is accompanied by an increase of earthquakes and fault movement as crust adjusts to the loss in weight.

We might have seen it in the past. AlaskaThe melting glaciers caused fault stability to be less stable, resulting in small earthquakes. Possiblely the magnitude 7.2 St Elias earthquake1979

Another factor is low air pressure associated with storms and typhoons, which studies have also shown can trigger earthquakes in areas where the Earth’s crust is already under stress. Even very small changes in pressure can cause fault movement. An analysisThere were two earthquakes in eastern Taiwan in 2002 and 2007.

So how do we prepare?

Many mitigation strategies to combat climate change must also include elements that increase tsunami preparedness.

This could include incorporating sea level rise projections into tsunami prediction models and building codes for infrastructure along vulnerable coasts.

Researchers can also make sure that scientific models of climate impacts include the projected rise in earthquakes, land slides, and volcanic activity and the increased tsunami risk.

Continue reading:
What causes a tsunami in the first place? A scientist studying the ocean explains how these waves can be so destructive.