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Hello. This is 6 Minute English
from BBC Learning English.
I’m Sam.
And I’m Neil. Agh, it’s raining again, Sam!
I’ve had enough! It’s been
drizzling, that’s raining lightly, all week…
I know what you mean, Neil.
Living in a wet country
like Britain I sometimes wish I
could push a magic button and stop it raining.
And ironically, people living in hot,
dry countries need rain but don’t get it.
If only we could control the weather…
Ah well it’s funny you should
say that, Neil, because you’re
not the first person to have that idea.
In this programme, we’ll be hearing about
‘cloud-seeding’ and ‘geo-engineering’, two
controversial methods scientists are using
to manipulate or change the weather.
And as usual, we’ll be learning
some new vocabulary as well.
Anything that stops it drizzling
sounds good to me, Sam.
I hate to disappoint you, Neil, but these ideas
involve making more, not less, rain.
We’ll learn the details soon but first I have a
question for you about the wettest
place in the world, a village which
gets nearly twelve metres of rain a year.
But where is it?
Is the wettest village on earth found in:
a) Ireland? b) New Zealand?
or, c) India?
Well, it rains a lot in Ireland
doesn’t it, so I’ll say that’s
where the wettest place on earth is.
OK, Neil. We’ll find out if that’s the
correct answer later in the programme.
The first type of weather manipulation we’ll hear
about is a way of getting snow and rain
out of clouds known as ‘cloud seeding’.
Airplanes fly through the clouds and
spray chemicals to make water particles
freeze and stick together as snowflakes.
These then fall as snow which
builds up during winter
before melting in spring to help water crops.
Listen as Charmaine Cozier, presenter of
BBC World Service programme,
The Inquiry, speaks with
Professor Katja Friedrich, an atmospheric
scientist at the University of Colorado:
The first cloud seeding experiments
took place in the 1940s.
In the years since, scientists are
often accused of meddling with nature.
People are thinking, yeah, you’re
putting some substances in
the atmosphere that should not be there.
Usually I respond and say, every time you
get into your car, every time you
get on an airplane you put substances
in the air that don't
belong, so you're also playing God.
Because everyone needs
water, cloud seeding is
becoming more and more popular, with
scientists from over fifty countries using
the method to extract rain from clouds.
But some critics accuse these
scientists of meddling with
nature – trying to change something which
it’s not their responsibility to change.
In other words, they’re
accused of playing God – acting
as if they have unlimited
power and can do whatever they want.
Unlike cloud-seeding, the next type
of weather modification has never
been tested and is still just a theory.
‘Solar geo-engineering’ aims to reduce
global warming by reflecting sunlight
away from the Earth, back into space.
This involves putting tiny particles
called aerosols into the stratosphere - the
band of sky twenty kilometres
above the surface of the earth, about
twice as high as airplanes fly.
Although it’s never been tested, the
method is controversial, as
Charmaine Cozier discussed with Harvard
University professor of engineering,
David Keith, for BBC World Service’s, The Inquiry:
How controversial is this area?
There's lots of controversy around solar
geo-engineering - and for good reason.
People are, I think, sensibly scared
that this could provide an
excuse that allows countries or
companies to avoid doing the work
that has to be done to cut emissions.
But in fact, controversy has
really waxed and waned over time,
so in the early work on climate
change in the 1960s, and 70s and
early 80s, these ideas were just
part of the way we talked about what
might happen about climate change.
And then, as climate change became more
politically central, say in the
90s and 2000s, there was really a taboo.
David Keith believes
that geo-engineering could
provide an excuse for inaction on
climate change – a reason for countries to
explain why they did not take action.
He says controversy over the method has
waxed and waned - an idiom connected
with the cycle of the moon which
describes something that increases
then decreases over time.
In the 1960s
for example, geo-engineering
was uncontroversial, but by the
1990s it had become taboo - a
subject that is avoided
for social or religious reasons.
While these ideas to change
the weather have
potential benefits, other
suggestions - for example to position a
giant floating mirror between the
earth and sun - are highly controversial…
Although personally, I think
the idea of giant floating
umbrella above Britain would be good!
Ha! Well, just think -
there are even rainier
places to live Neil, as I asked
in my question: in which country
is the world’s rainiest village?
I guessed it was in Ireland.
Which was… the wrong answer,
I’m afraid.
In fact, Mawsynram,
the world’s wettest village, is in the
Khasi hills of north-eastern India.
With around twelve metres
of rain a year, I guess it’s not
somewhere you’ll be visiting, Neil!
OK, let’s recap the vocabulary
we’ve learned starting with drizzling
which means raining lightly.
If you’re meddling you’re trying
to change something
which is not your responsibility
or without being asked to.
Someone who is playing God is acting
as if they control everything and
can do whatever they want.
An excuse is a reason you give to
explain why you did something wrong.
If something waxed and waned, it
grew stronger then weaker over time.
And finally, a taboo is a subject that
avoided for social or religious reasons.
Once again, our six minutes are up!
Bye for now!
Bye bye!