- Our planet boasts some conditions almost beyond the human
imagination. But now modern scientific techniques are starting to tell
a story of just how threatening nature can be.
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- The World's Biggest Wave
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- On 15 September 2004 the eye of a giant storm passed
over a set of scientific gauges on the seabed of the Gulf of Mexico. The
instruments measured the size of the waves created by Hurricane Ivan as
it headed towards the American coast.
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- A study published today in the journal Science reveals
that the hurricane created waves measuring at least 90 feet (30m) from
crest to trough - the tallest and most extreme open-ocean waves ever recorded
by modern instruments.
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- By monitoring differences in water pressure on the seabed,
the scientists were able to estimate the size of the column of water overhead.
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- The findings demonstrate that scientists have in the
past underestimated the size of the waves that can be generated by hurricanes,
said William Teague from the Naval Research Laboratory in Stennis Space
Centre, Mississippi.
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- The waves recorded were the size of a 10-storey building
but were probably not the largest that the hurricane had generated, Dr
Teague said.
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- He estimated that even bigger waves up to 132 feet tall
were being created in other parts of the huge tropical cyclone.
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- Hurricane Ivan had already ripped through the island
of Grenada when the seabed readings were taken, and went on to cause death
and destruction on Jamaica, the Cayman island and finally the United States
where it petered out.
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- The wave-measuring instruments on the seabed are shaped
liked barnacles and are designed to help engineers build structures such
as oil platforms that have to withstand extreme conditions.
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- The worst hurricane
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- Hurricane Mitch, which killed about 11,000 people in
1998, is considered to be the most destructive hurricane of modern times.
Mitch struck Central America in October and November, destroying about
100,000 homes and leaving about 2.5 million people dependent on relief
aid. Wind speeds reached 180mph for a 24-hour period, making it the strongest
hurricane in the Caribbean in more than a decade.
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- Hurricanes normally last for between nine and 10 days
and move westwards at a speed of about 12mph, gradually curving away from
the equator as they move.
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- They are one of the most dramatic and destructive forces
in nature. According to Bill McGuire, author of Surviving Armageddon and
a natural hazards expert at University College London, the past 12 months
have been the worst on record for hurricanes.
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- Five have struck Florida alone and the forecast for this
year is that there will be about four times as many hurricanes as the annual
average.
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- Heaviest rainfall
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- About 1.8 inches (4.6cm) of rain fell in a minute at
Basse Terre in Guadeloupe on 26 November 1970 and 53 inches fell over a
12-hour period at Belouve on La Reunion island in the Indian Ocean.
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- The highest average annual rainfall - some 450 inches
- is at Mt Waialeale in Hawaii. The highest recorded annual rainfall was
1,042 inches (nearly 87 feet) at Cherrapunji, India. It also recorded the
highest rainfall in a calender month - 366 inches, or 30ft 6in.
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- Bombay last month recorded the highest rainfall in a
single day in India - 37.1 inches.
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- Coldest place on Earth
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- The lowest recorded temperature outside a science laboratory
was at the Russian research station at Vostok in Antarctica on 21 July
1983. It was minus 89.2C (minus 128.6F), cold enough to freeze your breath.
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- The temperature there is regularly between minus 30C
and minus 60C, a result of the exceptionally high speed of the winds at
this part of the frozen continent and the lack of solar radiation during
the winter, when the days pass in complete darkness.
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- And while minus 89.2C is the official record, Vostok
station reported, unofficially, that Vostok reached the temperature of
minus 91C during the winter of 1997.
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- Hottest place on Earth
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- There are many contenders for this record. A weather
station in El Azizia in Libya recorded 57.8C (136F) - hot enough to fry
an egg - in 1922.
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- This record meets technical requirement in being made
using a thermometer 5 feet above the ground in an enclosed, shaded area.
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- Other locations have, however, almost certainly been
hotter, but no formal record is available.
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- The Dallol Depression in Ethiopia, which is more than
100 meters below sea level, features yellow sulphur fields among the white
salt beds. Temperatures can reach as high as 63C.
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- Another contender is Death Valley in California, which
is also below sea level, where temperatures have been recorded as reaching
49C.
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- Wave of tornados
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- In April 1974, southern and mid-western US suffered its
worst tornado episode. Over a 24-hour period, 148 swept through the region.
Thirteen states from Alabama to Virginia were affected. After 16 hours,
330 people were dead and 5,484 were injured in a damage path covering more
than 2,500 miles. Tornadoes form during thunder storms when warm, humid
air collides with colder air to form a swirling vortex.
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- Driest place on Earth
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- The Atacama desert in northern Chile is the most arid
tract of land known. On average the buff-coloured sands of this region
receive less than 0.004in of rain a year. Some parts of the desert have
not seen rainfall in 400 years; scientists see it as a good training ground
for testing instruments to search for the presence of water on other planets.
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- The Atacama desert owes its conditions to the fact that
it is sandwiched between the high mountains of the Andes on the east and
the exceptionally cold currents of the Pacific Ocean in the west. Bodies
buried there by prehistoric people are almost perfectly preserved as natural
mummies.
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- The world's worst modern meteor strike
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- Early in the morning of 30 June 1908 a large and mysterious
explosion occurred in the sky over eastern Siberia. Visitors to the site
of the explosion at Tunguska in northern Russia saw catastrophic damage,
with thousands of acres of forest felled.
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- Local reindeer herdsmen said they were blown off their
feet during the impact. The fireball lit up the night sky for hundreds
of miles around - some say that it could even be seen from London.
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- Scientists now believe the event was caused by a large
meteorite breaking up as it entered the Earth's atmosphere. The lump of
space rock exploded at an altitude of about 4 miles (6.4km), sending a
huge pulse of explosive energy to the ground that flattened everything
in its path.
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- The most destructive earthquakes
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- On 22 May 1960 an earthquake with a magnitude of 9.5
on the Richter scale struck off the coast of Chile. It is estimated to
have accounted for about a quarter of the seismic energy released by all
earthquakes in the past century. The US Geological Survey said that the
earthquake killed 2,000 people, injured 3,000 and made another 2 million
homeless. Tsunamis travelled across the Pacific, causing millions of pounds
worth of damage in Hawaii, Japan, the west coast of the US and the Philippines.
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- However, the most destructive earthquake in modern times
was in Tangshan, north-east of the Chinese capital of Beijing, in 1976.
Officially the death toll was 242,419; unofficial estimates said 750,000.
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- The world's biggest volcanos
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- The most destructive volcanic eruption in modern times
was that of Tambora on the Sumbawa island of Indonesia. It began on 5 April
1815 with a moderate explosion. Five days later "three columns of
fire" rose into the sky and an estimated 50 cubic kilometres of molten
magma were expelled. An estimated 92,000 died from the explosion or resulting
starvation.
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- The debris thrown into the atmosphere caused global climate
change. Crops failed as far away as America and many tens of thousands
of people died from famine in the immediate vicinity of the eruption.
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- © 2005 Independent News & Media (UK) Ltd.
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- http://news.independent.co.uk/world/environment/article303759.ece
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