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Seawater freezes at
-2
0
C
(28
0
F) because the salt in it lowers its freezing point.There is enough electricity
in a single fork of lightning
to light a town for a year.
Greenland is the largest island in the
world, with an area of 2,133,086 sq km
(836,109 sq miles). Australia is larger, but
is considered to be a continent rather than
an island.The largest diamond mine in the
world is at Mirny in Siberia. The hole
in the ground is 1,200 m (4,000 ft)
across – so big that helicopters are
sucked into it if they fly too close.
There are 14 mountains more than
8,000 m (26,000 ft) high, all of
them in the Himalayas.Clouds contain tiny droplets
of water floating in air.
A raindrop contains up to
2 million cloud droplets.A delay of three
seconds between
seeing lightning
and hearing thunder
means that the lightning
is 1 km (0.6 miles) away.There are 15,000 bush fires in Australia
every year, as trees and shrubs burst into flames
in the extreme heat. Many plants rely on these
fires to release their seeds.The surface of the Dead Sea in the
Jordan Valley is 408 m (1,340 ft) below
sea level. Its water is so salty that
nothing can live in it except simple
organisms, such as algae.The world’s shortest river is the North Fork
Roe River, in Montana, USA, which is just
18 m (59 ft) long.In 1873 , frogs rained
down from the sky
in Kansas City, USA.
In 1948 , a group of
golfers in Bournemouth,
England, was showered
with herring. The
animals had been swept
up into the clouds by
strong winds.
The hardness of rocks is measured using
the Mohs scale, with soft talc at 1 and
hard diamond at 10.The largest meteor crater is Vredefort
in South Africa, which is 300 km
(186 miles) wide. It was created
when a meteor about
10 km (6 miles) wide
collided with Earth
2 billion years ago.As deserts grow
larger, the amount
of land available
to grow crops is
shrinking at a rate
of 120,000 sq km
(46,000 sq miles)
every year.Seven
per cent of the
world’s oceans
are covered in ice.
Enough water to fill 2 million baths flows out of the
River Amazon into the Atlantic Ocean in one second.
This is five times as much water as the
second-largest flow, from
the River Ganges.On average,
there are just
five days a
year when it
doesn’t rain
on Mt Waialeale
in Hawaii.On the afternoon
of 31 May 1985,
41 tornadoes were
reported around the States
of Pennsylvania and Ohio
in the USA. Seventy-five
people were killed.The eruption of Mount St Helens
in the USA on 18 May 1980 set
off an avalanche travelling at
400 km/h (250 mph).The oldest rocks in the Grand
Canyon were formed 2 billion
years ago.
The Holderness coastline in east
England is being eroded away
by the North Sea at a rate
of 1.5 m (5 ft) per year.More than
30 per cent of
New Zealand’s
greenhouse gas
comes from methane
in the burps and farts
of the country’s 45 million
sheep and 10 million cows.Over the last 10,000 years, 80 per cent
of the world’s forests have been cut down
by humans.TO TAKE A CLOSER LOOK AT OUR PLANET, SEE PAGES 152–189Earth’s
atmosphere is
700 km
(430 miles)
thick.
No two
snowflakes
have the same
shape, but they
all have six
sides.
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