5 ways climate change can increase the threat of tsunamis. From collapsing sea ice shelves to rising sea levels

Hunga Tonga Ha’apai was triggered by an enormous eruption of an underwater volcano in Tonga. tsunamiIt reached countries all along the Pacific Rim, even causing havoc in some countries. Katastrophic oil spillagePeru has 21 beaches.

Tonga saw waves that were about 2 metres high before the sea-level gauge failed. Waves 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 changeCould they also play a part? 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 earthquakes and volcanic eruptions. This can lead to tsunami-related problems. Here are five ways this might happen.

1. Sea level rise

If greenhouse gas emissions continue at high rates, the global average sea level will remain Promised to increaseBetween 60 centimetres to 1.1m Two thirds of them 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 a modest rise in sea level can dramatically increase the frequency and severity of flooding when a tsunami strikes, as the tsunami can travel farther inland.

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 in the future, smaller tsunamis may have the same impact today 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 are possibleOn impact, a landslide enters water or water is moved by an underwater 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 resulted in a landslide that deposited 180 million tonnes of rock into narrow fjords in 2015. 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 have predicted that large ice shelves like the Thwaites Glacier in Antarctica will form. Most likely to collapseIn the next five- to ten years. Similar to the Greenland icesheet. Thinning and retreatingAt an alarming rate

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 riskThe calving process and the breakup.

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 is on the rise.

The correlation between climate warming and more volcanic eruptions isn’t yet well constrained or understood. It may be related to 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 tsunami risk.

First, the weight of ice sheet may be Repressing fault movement and earthquakes. 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.

This may be something we have already seen. AlaskaIn this area, melting glaciers have reduced fault stability, causing many small earthquakes. Perhaps 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 trigger fault movement. An analysisIdentified earthquakes in eastern Taiwan between 2002 and 2007.

How can we prepare for this?

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

This could include including projected sea level rise in tsunami prediction models and in building codes that address infrastructure along vulnerable coastlines.

Researchers can also guarantee that climate models include the projected increase of earthquakes, landslides, volcanic activity, as well as the increased tsunami danger this will cause.

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