QI: The Book of General Ignorance - the Noticeably Stouter Edition (3 page)

Antarctica. Parts of the continent have seen no rain for two million years.

A desert is technically defined as a place that receives less than 254 mm (10 inches) of rain a year.

The Sahara gets just 25 mm (1 inch) of rain a year.

Antarctica’s average annual rainfall is about the same, but 2 per cent of it, known as the Dry Valleys, is free of ice and snow and it never rains there at all.

The next-driest place in the world is the Atacama Desert in Chile. In some areas, no rain has fallen there for 400 years and
its average annual rainfall is a tiny 0.1 mm (0.004 inches). Taken as a whole, this makes it the world’s driest desert, 250 times as dry as the Sahara.

As well as the driest place on earth, Antarctica can also claim to be the wettest and the windiest. Seventy per cent of the world’s fresh water is found there in the form of ice, and its wind speeds are the fastest ever recorded.

The unique conditions in the Dry Valleys of Antarctica are caused by so-called katabatic winds (from the Greek word for ‘going down’). These occur when cold, dense air is pulled downhill simply by the force of gravity. The winds can reach speeds of 320 kph (200 mph) evaporating all moisture – water, ice and snow – in the process.

Though Antarctica is a desert, these completely dry parts of it are called, somewhat ironically, oases. They are so similar to conditions on Mars that NASA used them to test the Viking mission.

The Western

Highlands of Kenya in Africa.

In terms of annual downpour, Kericho in Kenya has more hail than anywhere else on earth, since it falls on average 132 days each year. By comparison, the UK averages only fifteen hail-days in a year and the worst affected area in the US, the eastern Rockies, experiences an average of forty-five hail-days a year.

What causes the abundance of hail is not fully understood. Kericho is the home of Kenya’s tea plantations, and a 1978 study showed that organic litter from the tea plants gets stirred into the atmosphere, where it acts as a nucleus around which hailstones can grow.

Another theory is that the high altitude of the region could be to blame, as the shape of the terrain causes a large uplift of warm air which quickly condenses. This, and the reduced distance between the freezing level (about 3 miles up) and the ground, reduces the chance of hailstones melting.

The average hailstone is about quarter of an inch across, but they can grow large enough to dent cars, shatter greenhouses and even injure people.

The largest single hailstone ever recorded in the United States was 7 inches in diameter, 18.75 inches in circumference, and weighed in at just under a pound. It fell into the back yard of a house in Aurora, Nebraska, in June 2003. This is off the end of the official US scale for describing hailstones which starts at ‘pea’ and rises progressively through ‘mothball’, ‘walnut’ and ‘tea-cup’ to ‘softball’. The Aurora hailstone was the size of a small melon and would have hit the ground at 100 mph.

Hail costs the US a billion dollars each year in damage to property and crops. A hailstorm that struck Munich, Germany,
in July 1984 caused an estimated billion dollars’ worth of damage to trees, buildings and motor vehicles in a single afternoon. Trees were stripped of their bark and whole fields of crops were destroyed. Over 70,000 buildings and 250,000 cars were damaged and more than 400 people were injured.

However, the world’s worst hailstorm occurred in the Gopalanj district of Bangladesh on 14 April 1986. Some of the hailstones weighed over two pounds and at least ninety-two people were killed.

It’s on Mars.

The giant volcano Mount Olympus – or
Olympus Mons
in Latin – is the highest mountain in the solar system and in the known universe.

At 22 km high (14 miles) and 624 km (388 miles) across, it is almost three times the height of Mount Everest and so wide that its base would cover Arizona, or the whole of the area of the British Isles. The crater on the top is around 72 km (45 miles) wide and over 3 km (nearly 2 miles) deep, easily big enough to swallow London.

Mons Olympus doesn’t conform to most people’s idea of a mountain. It is flat-topped – like a vast plateau in a sea drained of water – and its sides aren’t even steep. Their slight incline of between one and three degrees means you wouldn’t even break sweat if you climbed it.

We traditionally measure mountains by their height. If we measured them by their size, it would be meaningless to isolate one mountain in a range from the rest. That being so, Mount Everest would dwarf Olympus Mons. It is part of the
gigantic Himalaya–Karakoram–Hindu-Kush–Pamir range which is nearly 2,400 km (1,500 miles) long.

Mauna Kea, the highest point on the island of Hawaii.

The inactive volcano is a modest 4,206 m (13,799 feet) above sea level, but when measured from the seabed to its summit, it is 10,200 m (33,465 feet) high – about three-quarters of a mile taller than Mount Everest.

As far as mountains are concerned, the current convention is that ‘highest’ means measured from sea level to summit; ‘tallest’ means measured from the bottom of the mountain to the top.

So, while Mount Everest, at 8,848 m (29,029 feet) is the highest mountain in the world, it is not the tallest.

Measuring mountains is trickier than it looks. It’s easy enough to see where the top is, but where exactly is the ‘bottom’ of a mountain?

For example, some argue that Mount Kilimanjaro in Tanzania – at 5,895 m (19,340 feet) – is taller than Everest because it rises straight out of the African plain, whereas Everest is merely one of many peaks topping the enormous base of the Himalayas, shared by the world’s next thirteen highest mountains.

Others claim that the most logical measure ought to be the distance of a mountain’s peak from the centre of the Earth.

Because the Earth is a flattened rather than a perfect sphere, the equator is about 21 km (13 miles) further from the centre of the Earth than the poles.

This is good news for the reputation of those mountains that are very close to the equator – like Mount Chimborazo in the Andes – but it also means accepting that even the beaches in Ecuador are ‘higher’ than the Himalayas.

Though massive, the Himalayas are surprisingly young. When they were formed, the dinosaurs had been dead for 25 million years.

In Nepal, Everest is known as
Chomolungma
– ‘Mother of the Universe’. In Tibet, it is called
Sagamartha
– ‘Forehead of the Sky’. Like any healthy youngster, it is still growing – at the not very exciting rate of 4 mm (less than a quarter of an inch) a year. 

It’s a mushroom.

And it’s not even a particularly rare one. You’ve probably got the honey fungus (
Armillaria ostoyae
) in your garden, growing on a dead tree-stump.

For your sake, let’s hope it doesn’t reach the size of the largest recorded specimen, in Malheur National Forest in Oregon. It covers 890 hectares (2,200 acres) and is between 2,000 and 8,000 years old. Most of it is underground in the form of a massive mat of tentacle-like white
mycelia
(the mushroom’s
equivalent of roots). These spread along tree roots, killing the trees and peeping up through the soil occasionally as innocent-looking clumps of honey mushrooms.

The giant honey fungus of Oregon was initially thought to grow in separate clusters throughout the forest, but researchers have now confirmed it is the world’s single biggest organism, connected under the soil.  

A grapefruit.

Quite interestingly, a blue whale’s throat is almost exactly the same diameter as its belly button (which is about the size of a side plate), but a little smaller than its eardrum (which is more the size of a dinner plate).

For eight months of the year, blue whales eat virtually nothing, but during the summer they feed almost continuously, scooping up three tons of food a day. As you may remember from biology lessons, their diet consists of tiny, pink, shrimp-like crustaceans called
krill
, which slip down a treat. Krill come conveniently served in huge swarms that can weigh over 100,000 tons.

 The word krill is Norwegian. It comes from the Dutch word
kriel
, meaning ‘small fry’ but now also used to mean both pygmies and ‘small potatoes’. Krill sticks have been marketed with reasonable success in Chile but krill mince was a bit of a disaster in Russia, Poland and South Africa owing to dangerously high levels of fluoride. It came from the krill’s shells which were too small to pick off individually before mincing.

The narrow gauge of a blue whale’s throat means it couldn’t have swallowed Jonah. The only whale with a throat wide enough to swallow a person whole is the sperm whale and, once inside, the intense acidity of the sperm whale’s stomach juices would make survival impossible. The celebrated case of the ‘Modern Jonah’ in 1891, in which James Bartley claimed to have been swallowed by a sperm whale and rescued by his crew mates fifteen hours later, has been nailed as a fraud.

Aside from its throat, everything else about the blue whale is
big
. At 32 m (105 feet) in length, it is the largest creature that has ever lived – three times the size of the biggest dinosaur and equivalent in weight to 2,700 people. Its tongue weighs more than an elephant; its heart is the size of a family car; its stomach can hold more than a ton of food. It also makes the loudest noise of any individual animal: a low frequency ‘hum’ that can be detected by other whales over 16,000 km (10,000 miles) away.