Iain Stewart
BBC, 2010
http://www.bbc.co.uk/programmes/b00qclqx
http://www.youtube.com/watch?v=gYM5hBWZfwQ
http://www.imdb.com/title/tt1588224/
ShareSeeking
Ep. 1 - Deep Earth
Excerpts:
6500 years ago, Timna Valley, Israel's Negev Desert
"When malachite is heated, it releases a metal - Copper"
...
For the first time, we were transforming what the Earth offered us
and in the process creating entirely new resources.
And copper was just the start of thing to come.
About 5000 years ago 'tin' was added to copper to form
a new, more durable metal alloy - bronze.
By 3000 years ago refinements to the smelting process
meant iron could be smelted out of rock."
"Metal tools became the foundation for human civilization.
"The Earths' crust is divided into huge piece called 'plates'.
where they meet are cracks, known as 'fault lines.'
Timna is next to the Dead Sea fault
which separates Africa from Arabia.
"In fact, if you look back at the ancient world,
you see a stong link between fault lines,
water and the growth of some of the first cities.
... nearby is Jericho, said to be the oldest city in the world.
It was first settled 10,000 years ago
because deep ground water rose along fault lines
to create fertile pastures in the desert.
More unusual is the ancient Roman city of Hierapolis.
It was built next to these terraces of WHITE ROCK.
Here, it wasn't just water that was important -
minerals carried inthe water were thought to have revitalizing powers.
So Hierapolis became an important healing center in the Roman Empire."
FAULT LINES:
"Its a connection which lead 11 of the 13 most important civilizations
of the ancient world, unknowingly to build their cities
close to a plate boundary."
4000 years ago,
the island of Crete was home to the Minoans.
...
What the Minoans invented was the day off. (for sports)"
Archipelago, 100 km north of Crete
Today that island chain is known as Santorini,
famous for its pretty white houses and rugged coastline.
ASH OF THE VOLCANO.
This stuff is just like as silica glass.
it gets into your lungs and it just lacerates your lungs.
"But ancient history is lttered with tales of cities destroyed along plate boundaries.
And it's not just volcanoes that do the damage.
Fault lines are also home to another deadly force of nature.
Earthquakes."
"Hierapolis, with its famous health spa,
was destroyed by a giant earthquake in AD 60."
Jericho, has been hit over 15 time by large earthquakes.
Some believe it was this that famously brought its walls "tumbling down".
PLATE TECTONICS
"The key is that all the plates which divide the Earth's surface
are continually on the move.
Where they collide they crumple the land
to form great mountain ranges, like the Himalayas."
When one plate slides underneath another, volcanoes form.
When two plates lock together, and then suddenly break free,
the jolt causes devastating earthquakes.
It's clear that many cities are located close by
In fact 10 of the 20 largest cities in the world
are nest to dangerous fault lines.
Most people probably think of Texas as America's oid state
but California was and still is one of the world's biggest oid producers,
drawing more than 700,000 barrels of crude oil out of the ground everyday.
The point is that in pure economic terms,
we're still financially better off living along a fault line than not,
even when it's one of the most active in the world.
But the problem that i have with that equation
is that life's not just about money.
HAGIA SOPHIA, Istanbul
In its, 1500 years history, its been a church and a mosque and now a museum.
The Hagia Sophia has stood through more than a dozen earthquakes,
without the benefit of modern technology.
________________________
Ep. 2 - Water
Excerpts
Water makes Earth alive.
6000 years ago Sahara Desert was wet.
More than 30% of all fresh water on Earth is under our feet.
I'm travelling to the very epicenter of the monsoon,
a place called Cherrapunjee,
which holds the world record for the hugest rainfalls in a single year.
... but here in Cherrapunjee, the annual average rainfall
is between 11 and 12 meters.
That's nearly the height of a four=storey building.
Streams turn to rivers, and rivers turn to torrents."
During these months, India's land surface heats up much more
than the surrounding Indian Ocean.
The high temp. reduces the density of the air,
creating low pressure.
That sucks moist ocean air onto the land,
which brings rain.
It's because the whole system is driven by the Sun's heat
that the rains come in the summer.
But it also means that the monsoon only lasts for three months of the year.
For the rest of the time, there's virtually no rain.
"And that's made India the largest user of groundwater in the world."
"The world's reservoirs now hold over 10,000 cubic kilometers of water.
That's five times as much water as in all rivers on Earth.
And because most of it is pooled in the more populated northern hemisphere,
away from the equator, the extra weight has slightly changed how the Earth
spins on its axis.
it's caused the Earth's rotation to speed up,
shortening the day by 8 millionths of a second in the last 40 years.
LA stealth the Sierra Nevada's Owens Valley's people's water.
Today, there are conflicts over water taking place all around the world.
Israel, the Palestinians, Syria and Jordan
dispute access to the River Jordan.
Egypt, Sudan and Ethiopia, quarrel over the waters of Nile.
on the Indus River, India and Pakistan are in conflict over dams
built on the rivers' tributary.
And these are only some of the more well known examples.
_________________________
Ep. 3 - Wind
Excerpts:
"These winds begin at the equator.
This is where the sun is at its hottest,
so the air is continually rising.
As it spreads away from the equator, it cools,
until between about 20 and 30 degrees latitude,
the air sinks back to Earth, heating up again in the process.
TRADE WINDS
He (Columbus) had discovered what we now call the Trade Winds -
winds that blow steadily in a south-westerly direction.
It was the trade winds that took him all the way from the African coast
to the Bahamas.
WESTERLY winds
blow west to east.
Between 20 and 30 degrees latitude,
the winds blew east to west.
Between 40 and 50 degrees,
it blew in the opposite direction.
In the 400 years after Columbus made his epic voyage,
nearly 12 million slaves were shipped across the Atlantic.
(New Ocean Trade Routes)
Sailing ships now bypassed the old desert trade routes.
JET STREAMS
Jet streams are powerful currents of fast-moving wind
the whip along the boundary between two cells.
They're several hudred km wide but only a few km thick
They snake around the globe in wavy loops,
directing the course of weather systems below.
50 million years ago,
India collided with Asia,
and that pushed up the Himalayas.
HURRICANES
Each 1 degree rise in sea temp.
increase wind speeds by more than 20 km per hour.
It's spin of the Earth that gives a hurricane its distinctive spiral shape.
"... Then, Just over 3000 years ago, sailors set off from Asia
and begain to spread to nearly every island in this vast (Pacific) ocean,
ending up in the distant far-flung islands
of Hawaii, New Zealand and Easter Island.
"it's thought that this whole area (Pacific Ocean) was peopled by going from west to east (from Africa to America), but the thing is, in this region, the winds blow in the opposite direction - from east to west. Trying to sail into the wind from such long distances
would have taken a lifetime.
So quite how they did this has always been a bg mystery.
EL NINO:
Every few years,
warm water from the west Pacific
surges into the cooler waters of the east.
This warm water heats the air above, changing air pressure
and making the trade winds weaken or swap directions completely.
Today we know this phenomenon as El Nino.
___________________________
Ep. 4 - Fire
Excerpts:
"30,000 bolts of lightning hit the ground every hour.
"Around 1.5 million years ago,
early humans learnt how to control fire.
"Fire was the weapon that began our conquest of the planet.
"But 6000 years ago, our ancestors discovered the trick or burning wood
in a low-oxygen environment.
it only partially burns,
but in doing so it creates a much purer, carbon-rich fuel...
charcoal.
And that can burn at 1100 degrees Celsius...
hot enough to melt metal out of rock.
The invention of metal smelting culminating in the use of iron,
was one of the most critical turning points in human history.
Our mastery of metal gave us tools...
Money and Weapons.
In prehistoric times,
Britain had been almost completely covered in forest,
but by the end of the 16th century,
90% of the ancient woodland had gone.
Ironically, China is now the biggest user and producer of coal in the world.
To create so much salt, you need to evaporate an awful lot of seawater.
Usually, this happens in shallow seas
which get cut off from the rest of an ocean.
Seawater then evaporates, leaving behind a thick layer of salt.
AZERBAIJAN, Naftalan
"Within 20 years, these fields were the site
of the first great global oil boom.
From across the world,
entrepreneurs rushed to Azerbaijan to make their fortunes.
Some succeeded so well that their names are almost legendary.
THE SHELL company started life here,
and the NOBEL brothers of Nobel prize fame
built their business empire on Azeri oil.
After Azerbaijan faded from prominence,
the Middle East became the key oil-producing region in the world.
"This whole mountainside (in Iran) is covered in salt
that's oozed upwards from deep inside the Earth
the remains of a long lost ocean."
Salt is similar to ice becuae it's soft and plastic, which is why it flows.
Where Salt There Oil:
"It's easy to see why geologists searching for oil go looking for salt."
OILY ROCKS, former Soviet Union
a town built on Caspian Sea to dig the oil.
50km far from land. 2000 people live and work here.
built football grounds and even a mosque.
"Today, we're burning it far faster than the planet can make it.
It would take the Earth tree millin years to make enough oil
for just one year of our consumption.
____________________________
Ep. 5 - Human Planet
Excerpts:
It's thought that farming began around 1100 years ago
in the Middle East,
in what's known as the Fertile Crescent.
it took a while to catch on,
but by 7000 years ago it was spreading fast,
across Europe and Asia.
"Every year we burn around 31 billion barrels of it -
that's 1000 barrels a second.
55 million years ago, methane started to erupt from the ocean in massive quantities.
no one is quite sure why it happened, but huge areas of the ocean would have been bubbling like this.
[50 million years ago Himalayas stood up.
and helped Arctic to cover in ice.]
It's a lesson about the most dramatic human influence on the planet -
the speed and scale at which we're changing the atmosphere.
Levels of carbon dioxide and methane are higher than any time
in the last 15 million years.
We can already see some of the effects.
The thickness of the Arctic sea ice has almost halved.
Some of the extra carbon dioxide we've pumped into the atmosphere
has been absorbed by the oceans.
This has increased their acidity by 30%,
hindering the growth of marine creatures, like corals.
Over the last few decades,
the frequency of extreme hurricanes has doubled in some areas.
We're at the beginning of a dramatic period of change.
At the heart of it is the greenhouse effect,
a global warming caused by the gases we release.
Up until now the effect or our impact on the planet,
whether good or bad,
have been accidental and unintended.
GLOBAL SEED VAULT
_____________________
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