Tsunamis

A Tsunami is one or a series of waves that occur after an earthquake, sea-quake, volcanic activity, slumps, or asteroid impacts in or near the sea. A mega tsunami is simply a larger occurrence of the phenomena. The energy of a tsunami is constant, a function of its height and speed. Thus, as the wave approaches land, its height increases while its speed decreases. The waves travel at high speed, more or less unnoticed where crossing deep water, but can increase to a height of 30 meters and more as they approach the coastline.

Without the loss of energy, this allows the wave to go ashore making a storm surge seem laughable. These waves are capable of crossing an ocean, toppling large buildings none of which could withstand the force of the wave, equivalent to the speed of a commercial airplane, nor the extreme flooding.

Where would the next Mega Tsunami come from? A volcano named Cumbre Vieja on the island of La Palma in the Canary Islands of North Africa is where geologists suspect the next tsunami could begin. The reason for the concern is that in 1949 during a volcanic eruption part of the island slid into the ocean before ending its descent. Should another large eruption of the Cumbre Vieja occur, the western side of the island is likely to collapse into the Atlantic.

Predicting the next eruption isn't a likely happening; geologists cannot say whether or not the next eruption will be the one to make the island shed its western shore. Not to be pessimistic, but we can't stop tsunamis. Phenomena of this magnitude literally HAVE no way to be diverted. These are naturally occurring events, and next to the impressive force of mother nature, man would not stand much chance.

The only alternative is evacuating when the volcano (Canaries) starts to erupt, possibly giving a few days or weeks warning.

1. Comprehension exercises

1.a. According to the text

• A tsunami may be caused by some volcanic activity.
• Waves don't vary their height and speed.
• A tsunami occurs before an asteroid impacts in the sea.

1.b. According to the text

• In 1949 the western part of the island slid into the sea
• Some waves travel at the speed of a commercial airplane.
• In 1949 a volcano of La Palma was called Cumbre Vieja

1.c. The nearer a wave is the faster it goes.

(Answer "True" or "False" AND write the sentence supporting this idea)

• FALSE: "...as the wave approaches land, its height increases while its speed decreases."

1.d. It is difficult to predict when the next tsunami is going to occur.

(Answer "True" or "False" AND write the sentence supporting this idea)

• TRUE: "Predicting the next eruption isn't a likely happening."

2. Do the following grammar exercises according to the instructions given

2.a. Complete the second sentence so that it has a similar meaning to the first one

It will be better for you not to have spoken in that way.

• You had better not have spoken in that way.

2.b. Turn the two sentences into a clause with "such"

He behaves very rudely. I have never seen anything like that.

• I have never seen such a rude behaviour.

2.c. Turn the two sentences into a relative clause

There was a meeting yesterday. I couldn't understand its purpose.

• There was a meeting whose purpose I couldn't understand.

2.d. Rewrite the sentence using "despite"

He didn't succeed in the business. He made a huge effort.

• Despite making a lot of efforts he didn't succeed in the business/Despite his efforts.

 

3. Identify ONLY FOUR words from their definitions

• sudden falls of land: slumps
• becomes less, goes down: decreases
• not seen: unnoticed
• gradual decline in amount or activity: loss
• stand up or offer resistance to something, not be damaged or broken by something: withstand
• break down, fall down, crap up: collapse

+EXÁMENES RESUELTOS