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Hello. This is 6 Minute English from
BBC Learning English. I'm Neil.
And I'm Georgina.
With no end in sight to the coronavirus
pandemic, many people can't wait for
the year 2020 to end.
But with the coronavirus dominating
the newspaper headlines, attention
has moved away from an equally
serious global issue which has
quietly been getting worse -
climate change.
August 2020 saw the hottest
temperature recorded anywhere
in modern times - 54.4 degrees
Celsius in California's Death Valley.
The same month also saw record
amounts of ice melting into the
oceans around Greenland and the
Arctic - huge icebergs breaking
away from the edge of the ice
sheet - a thick layer of ice which
has covered a large area
for a long time.
Greenland's ice sheet is three
times the size of Texas and almost
2 kilometres thick. Locked inside
is enough water to raise sea levels
by 6 metres.
But global heating and melting
polar ice has many scientists
asking whether it's now too late
to stop. Have we have reached the
point of no return? In this programme,
we'll looking at the effects of climate
change on the Arctic and asking
if it s too late to change.
And learning some of the related
vocabulary too. Now, Georgina,
you mentioned record levels of
ice melt in the North Pole but
the scale is hard to take in. The
amounts are so big they're
measured in gigatonnes - that's
a billion metric tonnes.
Imagine a giant ice cube
1 kilometre by 1 kilometre
by 1 kilometre.
So my quiz question is this:
how many gigatonnes of ice
are now melting into the ocean
every year? Is it: a) 450 gigatonnes?,
b) 500 gigatonnes?, or
c) 550 gigatonnes?
I'll take a guess at b)
500 gigatonnes.
OK, Georgina, we'll find out
later. Now, glaciologist Michalea
King has been monitoring the
melting of Arctic ice by satellite.
Here she is answering a question
from BBC World Service programme,
Science in Action, on whether the
destruction of the ice sheet is
now unavoidable:
If we were to say ... define a
tipping point as a shift from
one stable dynamic state to
another, this certainly meets
that criteria, because we're
seeing now that the ice sheet
was more or less in balance prior
to 2000 where the amount of ice
being drained from the glaciers
was approximately equal to
what we are gaining on the
surface via snow every year.
Ice is made from snow falling on
Greenland's glaciers - large,
slow-moving masses of ice.
At the same time though, ice is
also lost through melting.
These two processes of
making and melting ice kept
the ice level in balance - having
different parts or elements
arranged in the correct
proportions. Essentially the
melting ice was replaced
by newly frozen ice.
But now, the glaciers are
shrinking faster than new ice
is being accumulated and the
situation may have reached
a tipping point - the time at
which a change or an effect
cannot be stopped.
So, does this mean that global
heating and ice melting are now
running automatically, separate
from the amount of greenhouse
gases humans are pumping into
the atmosphere? And does that
mean should just give up on
the planet?
In fact, the situation is far from
simple, as Michalea King explains
here to BBC World Service programme,
Science in Action:
We can definitely control the rate of
mass loss, so it's definitely not a
'throw your hands up' and jus
not do anything about it - give up
on the ice sheet kind of situation -
that's certainly not the message
I want to send... but it does seem
likely that we will continue to lose
mass... but of course, a slow rate
of mass loss is highly preferred
to large annual losses every year.
Michalea thinks that changes in
human activity can still slow the
rate - or speed at which something
happens, in this case the speed of
Greenland's ice sheet melting.
She's convinced it's not too late
for collective action to save the
planet, so it's not yet time to
'throw your hands up' - an idiom
meaning to show frustration and
despair when a situation becomes
so bad that you give up or submit.
It's a positive message but one
which calls for everyone to do
what they can before it really
is too late.
Because the rate of ice melt is
still increasing, right, Neil?
Yes, that s right - in fact, that
was my quiz question, Georgina...
do you remember?
Yes, you asked me how many
gigatonnes of Greenland's ice sheet
are now melting every year. I said
b) 500 gigatonnes.
And you were correct! In fact, some
of these giant ice cubes are like
small towns, almost a kilometre tall!
So there's still work to be done.
In this programme, we've been
looking at the rate - or speed -
of ice melt in Greenland's ice
sheet - the thick layer of ice
covering a large area of the Arctic.
Previously, the melting ice was
replaced by newly formed ice on
glaciers - large masses of
slow-moving ice. This kept the
Arctic in balance having
different elements arranged
in proportion.
But the effects of global
heating have brought us
close to a point of no return,
called a tipping point - the
time at which a change or an
effect cannot be stopped.
The situation is serious but
there's still time to take action
and not simply throw your
hands up - show frustration and
despair when you want to give up.
That's all for this programme, but if
you want to find out more about
climate change and Greenland's ice
sheets, search BBC's Science in
Action website.
And for more trending topics
and useful vocabulary, remember
to join us again soon at 6 Minute
English. Bye for now!
Goodbye!