R23 – Striking back at lightning with lasers


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Striking Back at Lightning with Lasers


1Seldom is the weather more dramatic than when thunderstorms strike. 2Their electrical fury inflicts death or serious injury on around 500 people each year in the United States alone. 3As the clouds roll in, a leisurely round of golf can become a terrifying dice with death – out in the open, a lone golfer may be a lightning bolt’s most inviting target. 4And there is damage to property too. 5Lightning damage costs American power companies more than $100 million a year.


1But researchers in the United States and Japan are planning to hit back. 2Already in laboratory trials they have tested strategies for neutralising the power of thunderstorms, and this winter they will brave real storms, equipped with an armoury of lasers that they will be pointing towards the heavens to discharge thunderclouds before lightning.


1The idea of forcing storm clouds to discharge their lightning on command is not new. 2In the early 1960s, researchers tried firing rockets trailing wires into thunderclouds to set up an easy discharge path for the huge electric charges that these clouds generate. 3The technique survives to this day at a test site in Florida run by the University of Florida, with support from the Electrical Power Research Institute (EPRI), based in California. 4EPRI, which is funded by power companies, is looking at ways to protect the United States’ power grid from lightning strikes. 5‘We can cause the lightning to strike where we want it to using rockets,’ says Ralph Bernstein, manager of lightning projects at EPRI. 6The rocket site is providing precise measurements of lightning voltages and allowing engineers to check how electrical equipment bears up.

Bad behavior


1But while rockets are fine for research, they cannot provide the protection from lightning strikes that everyone is looking for. 2The rockets cost around $1,200 each, can only be fired at a limited frequency and their failure rate is about 40 per cent. 3And even when they do trigger lightning, things still do not always go according to plan. 4‘Lightning is not perfectly well behaved,’ says Bernstein. 5‘Occasionally, it will take a branch and go someplace it wasn’t supposed to go.’


1And anyway, who would want to fire streams of rockets in a populated area? 2‘What goes up must come down,’ points out Jean-Claude Diels of the University of New Mexico. 3Diels is leading a project, which is backed by EPRI, to try to use lasers to discharge lightning safely – and safety is a basic requirement since no one wants to put themselves or their expensive equipment at risk. 4With around $500,000 invested so far, a promising system is just emerging from the laboratory.


1The idea began some 20 years ago, when high-powered lasers were revealing their ability to extract electrons out of atoms and create ions. 2If a laser could generate a line of ionisation in the air all the way up to a storm cloud, this conducting path could be used to guide lightning to Earth, before the electric field becomes strong enough to break down the air in an uncontrollable surge. 3To stop the laser itself being struck, it would not be pointed straight at the clouds. 4Instead it would be directed at a mirror, and from there into the sky. 5The mirror would be protected by placing lightning conductors close by. 6Ideally, the cloud-zapper (gun) would be cheap enough to be installed around all key power installations, and portable enough to be taken to international sporting events to beam up at brewing storm clouds.

A stumbling block


1However, there is still a big stumbling block. 2The laser is no nifty portable: it’s a monster that takes up a whole room. 3Diels is trying to cut down the size and says that a laser around the size of a small table is in the offing. 4He plans to test this more manageable system on live thunderclouds next summer. 5Bernstein says that Diels’s system is attracting lots of interest from the power companies.


1But they have not yet come up with the $5 million that EPRI says will be needed to develop a commercial system, by making the lasers yet smaller and cheaper. 2‘I cannot say I have money yet, but I’m working on it,’ says Bernstein. 3He reckons that the forthcoming field tests will be the turning point – and he’s hoping for good news. 4Bernstein predicts ‘an avalanche of interest and support’ if all goes well. 5He expects to see cloud-zappers eventually costing $50,000 to $100,000 each.


1Other scientists could also benefit. 2With a lightning ‘switch’ at their fingertips, materials scientists could find out what happens when mighty currents meet matter. 3Diels also hopes to see the birth of ‘interactive meteorology’ – not just forecasting the weather but controlling it. 4‘If we could discharge clouds, we might affect the weather,’ he says.


1And perhaps, says Diels, we’ll be able to confront some other meteorological menaces. 2‘We think we could prevent hail by inducing lightning,’ he says. 3Thunder, the shock wave that comes from a lightning flash, is thought to be the trigger for the torrential rain that is typical of storms. 4A laser thunder factory could shake the moisture out of clouds, perhaps preventing the formation of the giant hailstones that threaten crops. 5With luck, as the storm clouds gather this winter, laser-toting researchers could, for the first time, strike back.


Questions 1-3

Choose the correct letter, A, B, C or D.

Write the correct letter in boxes 1-3 on your answer sheet.

The main topic discussed in the text is

A  the damage caused to US golf courses and golf players by lightning strikes.

B  the effect of lightning on power supplies in the US and in Japan.

C  a variety of methods used in trying to control lightning strikes.

D  a laser technique used in trying to control lightning strikes.

According to the text, every year lightning

A  does considerable damage to buildings during thunderstorms.

B  kills or injures mainly golfers in the United States.

C  kills or injures around 500 people throughout the world.

D  damages more than 100 American power companies.

3  Researchers at the University of Florida and at the University of New Mexico

A  receive funds from the same source.

B  are using the same techniques.

C  are employed by commercial companies.

D  are in opposition to each other.


Questions 4-6

Complete the sentences below.

Choose NO MORE THAN TWO WORDS from the passage for each answer.

Write your answers in boxes 4-6 on your answer sheet.

4  EPRI receives financial support from …………

5  The advantage of the technique being developed by Diels is that it can be used ………………

6  The main difficulty associated with using the laser equipment is related to its ………………


Questions 7-10

Complete the summary using the list of words, A-l, below.

Write the correct letter, A-l, in boxes 7-10 on your answer sheet.

In this method, a laser is used to create a line of ionisation by removing electrons from 7 ………………. This laser is then directed at 8 ……………… in order to control electrical charges, a method which is less dangerous than using 9 ……………. .As a protection for the lasers, the beams are aimed firstly at 10 ………..

A  cloud-zappers B  atoms C  storm clouds
D  mirrors E  technique F  ions
G  rockets H  conductors I  thunder


Questions 11-13

Do the following statements agree with the information given in Reading Passage 1?

In boxes 11-13 on your answer sheet write

YES                      if the statement agrees with the claims of the writer

NO                        if the statement contradicts the claims of the writer

NOT GIVEN         if it is impossible to say what the writer thinks about this

11   Power companies have given Diels enough money to develop his laser.

12   Obtaining money to improve the lasers will depend on tests in real storms.

13   Weather forecasters are intensely interested in Diels’s system.