On the 15th local time, the Hong'aha Apay Volcano in the South Pacific island country of Tonga erupted violently: the sea surface "exploded" in a large area, huge ripples spread rapidly outward, and power and communication were interrupted for a time. The eruption also triggered a tsunami warning in the Pacific Rim, and evacuations have taken place in low-lying coastal areas such as Japan, Chile and Australia. Why did this eruption trigger such a massive alarm? What impact does it have on our lives?
Underwater Volcano Erupts, Setting Off Tsunami Warnings Across Pacific
Submarine volcanoes erupted, triggering a tsunami warning in the Pacific Ocean
By Aina J. Khan
An underwater volcano erupted on Saturday near the remote Pacific nation of Tonga, triggering tsunami warnings across the Pacific and for the West Coast of the United States, and causing strong waves and currents in many coastal areas.
On Saturday, near the remote Pacific island nation of Tonga, an undersea volcano erupted violently. Tsunami warnings followed in the Pacific and on the west coast of the United States, and in many coastal areas, the eruptions also caused violent waves and currents.
A four-foot tsunami wave was reported to have hit Tonga's capital, Nuku'alofa, sending people rushing to higher ground, and witnesses said ash had fallen from the sky.
A four-foot-tall (about 1.2-meter) tsunami reportedly hit the Tonga capital, Nuku'alofa, forcing people to rush to higher ground. Witnesses said volcanic ash fell from the sky.
Despite Tonga's geographical isolation, a booming sound after the initial eruption was heard as far away as New Zealand, 1,100 miles northeast of the archipelago's main island of Tongatapu.
Geographically, Tonga is isolated from the rest of the world. But the rumble of the volcano's initial eruption reached New Zealand, 1,100 miles (about 1,770 kilometers), northeast of Tongatapu, the main island of the Tonga Archipelago.
Across the Pacific warnings were sounded. New Zealand's National Emergency Management Agency advised people in coastal areas to expect "strong and unusual currents and unpredictable surges at the shore."
Alarms have been raised across the Pacific. New Zealand's National Emergency Management Agency advises people in coastal areas to prepare for "rough and abnormal ocean currents and unpredictable coastal surges".
The volcano, Hunga Tonga-Hunga Ha'apai, which is about 40 miles north of Tongatapu, had been relatively inactive for several years.
Located about 40 miles (about 64 kilometers) north of Tongatapu Island, The Hon Aha Apay Volcano has been relatively dormant for several years.
The volcano had erupted in 2014, spawning a new island that eventually became home to blossoming vegetation and barn owls, according to the BBC.
According to the BBC, the volcano erupted in 2014, creating a new island that later became home to lush vegetation and barn owl.
The V.E.I. of the eruption Saturday has not been estimated yet, but before the eruption, the volcano was estimated to be able to produce an eruption with a maximum V.E.I. of 2.
At present, the VEI intensity of Saturday's eruption (volcanic eruption intensity index) has yet to be estimated. But previously, it was estimated that the maximum intensity of the eruption was VEI level II.
Eruptions with a V.E.I. of 6 or higher send so much gas and particles so high into the atmosphere that they can have a cooling effect on the climate for several years, by reflecting more sunlight away from the Earth's surface. But eruptions of that magnitude occur very rarely.
Volcanic eruptions with a VEI index above six send large amounts of gases and particles into the upper layers of the atmosphere. They reflect more sunlight back away from the Earth's surface, which in turn cools the climate for years. But eruptions of this magnitude rarely occur.
【Content Expansion】
V.E.I.: Volcanic explosivity index
That is, a scale of volcanic eruption intensity is measured based on the volume of the ejecta, volcanic clouds, and qualitative observations, from level 0 to level 8, with intensity increasing step by step.
Good words
1.erupt
英 [ɪˈrʌpt] 美 [ɪˈrʌpt]
vi. (Volcanic) eruptions; (emotional) eruptions
expand:
erupt in/into something Some emotion suddenly explodes
He erupted into fury.
He was furious.
2.set something off
To make an alarm start ringing
3.trigger
英 [ˈtrɪɡə] 美 [ˈtrɪɡər]
(herein) v. Trigger, trigger; n. (gun's) trigger, trigger
trigger (off) something triggers/triggers something
Trigger (off) a wave of protests sparked a wave of protests
Trigger a memory triggers a memory
4.current
英 [ˈkʌrənt] 美 [ˈkɜːrənt]
(herein) n. Water flow; air flow; current; adj. Now, current
Air current airflow
electrical current
5.be reported to have done something
Reported to have done something (infinitive completion emphasizes that the action has taken place)
6.boom
English [buːm] Beauty [buːm]
to make a very deep and loud hollow sound; n. A low and huge roar
7.warnings are sounded
The alarm goes off
set off/trigger/sound warnings Sound alarms
sound
UK /saʊnd/ US /saʊnd/
to publicly give a warning
Quick, sound the alarm—there's a fire in the machine room!
Hurry up and pull the alarm, the machine room is on fire!
8.surge
英 [sɜːdʒ] 美 [sɜːrdʒ]
a sudden quick movement of a liquid
a tidal surge 涨潮
9.inactive
英 [ɪnˈæktɪv] 美 [ɪnˈæktɪv]
adj. (volcanic) dormant, inactive, inactive
The volcano has been inactive for 50 years.
The volcano has been dormant for 50 years.
10.spawn
English [spɔːn] Beauty [spɑːn]
vt. to cause something to develop or be produced
AI has spawned new business opportunities.
AI has created a large number of new business opportunities.
11.be/become home to something
Yes/Become... habitat/origin (often used to describe a country or place that has certain resources)
The Amazon rainforest is home to around 40,000 plant species.
The Amazon rainforest is home to about 40,000 species of plants.
12.so… (that)…
too...... That......
She was so tired (that) she couldn't think straight.
She was so tired that her mind was not spinning.
13.reflect
English [rɪˈflekt] 美 [rɪˈflekt]
v. (Physics) Reflection (sound, light, heat, etc.)
14.magnitude
英 [ˈmæɡnɪtʃuːd] 美 [ˈmæɡnətuːd; ˈmæɡnətʃuːd]
n. The intensity of the explosion, the magnitude of the earthquake; huge, significant, important
The prefix magni-: indicates that it is related to "large"
magnify UK /ˈmæɡnɪfaɪ/ US /ˈmæɡnəfaɪ/ v. 放大
magnificent UK /mæɡˈnɪfɪsnt/ US /mæɡˈnɪfəsnt/ adj. Magnificent
An operation of this magnitude is going to be difficult.
Such a large operation is very difficult to operate.
