Wednesday, September 24, 2014

Angkor, the greatest medieval city on Earth.

Beyond Angkor: How lasers revealed a lost city

Angkor Wat temple
Deep in the Cambodian jungle lie the remains of a vast medieval city, which was hidden for centuries. New archaeological techniques are now revealing its secrets - including an elaborate network of temples and boulevards, and sophisticated engineering.
In April 1858 a young French explorer, Henri Mouhot, sailed from London to south-east Asia. For the next three years he travelled widely, discovering exotic jungle insects that still bear his name.
Today he would be all but forgotten were it not for his journal, published in 1863, two years after he died of fever in Laos, aged just 35.
Mouhot's account captured the public imagination, but not because of the beetles and spiders he found.
Readers were gripped by his vivid descriptions of vast temples consumed by the jungle: Mouhot introduced the world to the lost medieval city of Angkor in Cambodia and its romantic, awe-inspiring splendour.
"One of these temples, a rival to that of Solomon, and erected by some ancient Michelangelo, might take an honourable place beside our most beautiful buildings. It is grander than anything left to us by Greece or Rome," he wrote.
His descriptions firmly established in popular culture the beguiling fantasy of swashbuckling explorers finding forgotten temples.
Today Cambodia is famous for these buildings. The largest, Angkor Wat, constructed around 1150, remains the biggest religious complex on Earth, covering an area four times larger than Vatican City.
It attracts two million tourists a year and takes pride of place on Cambodia's flag.

Find out more

Dr Dan Penny finds medieval carvings under a stone bridge in the Cambodian jungle
Follow the archaeological team in Cambodia as they uncover the mysteries of Angkor Wat. Watch Jungle Atlantis on Thursday 25 September at 20:00 BST on BBC Two or catch it later on the BBC iPlayer.
But back in the 1860s Angkor Wat was virtually unheard of beyond local monks and villagers. The notion that this great temple was once surrounded by a city of nearly a million people was entirely unknown.
It took over a century of gruelling archaeological fieldwork to fill in the map. The lost city of Angkor slowly began to reappear, street by street. But even then significant blanks remained.
Then, last year, archaeologists announced a series of new discoveries - about Angkor, and an even older city hidden deep in the jungle beyond.
An international team, led by the University of Sydney's Dr Damian Evans, had mapped 370 sq km around Angkor in unprecedented detail - no mean feat given the density of the jungle and the prevalence of landmines from Cambodia's civil war. Yet the entire survey took less than two weeks.
Their secret?
Lidar - a sophisticated remote sensing technology that is revolutionising archaeology, especially in the tropics.
Mounted on a helicopter criss-crossing the countryside, the team's lidar device fired a million laser beams every four seconds through the jungle canopy, recording minute variations in ground surface topography.
The findings were staggering.
Lidar technology has revealed the original city of Angkor - red lines indicate modern features including roads and canals
Image showing what is beneath the ground at Angkor
The archaeologists found undocumented cityscapes etched on to the forest floor, with temples, highways and elaborate waterways spreading across the landscape.
"You have this kind of sudden eureka moment where you bring the data up on screen the first time and there it is - this ancient city very clearly in front of you," says Dr Evans.
These new discoveries have profoundly transformed our understanding of Angkor, the greatest medieval city on Earth.
Phra Sav Ling Povn, palace of the leprous king, near the great temple of Angkor Wat, circa 1930 Phra Sav Ling Povn, palace of the leprous king, near Angkor Wat, circa 1930
At its peak, in the late 12th Century, Angkor was a bustling metropolis covering 1,000 sq km. (It would be another 700 years before London reached a similar size.)
Angkor was once the capital of the mighty Khmer empire which, ruled by warrior kings, dominated the region for centuries - covering all of present-day Cambodia and much of Vietnam, Laos, Thailand and Myanmar. But its origins and birthplace have long been shrouded in mystery.
A few meagre inscriptions suggested the empire was founded in the early 9th Century by a great king, Jayavarman II, and that his original capital, Mahendraparvata, was somewhere in the Kulen hills, a forested plateau north-east of the site on which Angkor would later be built.
But no-one knew for sure - until the lidar team arrived.
The lidar survey of the hills revealed ghostly outlines on the forest floor of unknown temples and an elaborate and utterly unexpected grid of ceremonial boulevards, dykes and man-made ponds - a lost city, found.
Relief map of Mahendraparvata
Most striking of all was evidence of large-scale hydraulic engineering, the defining signature of the Khmer empire.
By the time the royal capital moved south to Angkor around the end of the 9th Century, Khmer engineers were storing and distributing vast quantities of precious seasonal monsoon water using a complex network of huge canals and reservoirs.
Harnessing the monsoon provided food security - and made the ruling elite fantastically rich. For the next three centuries they channelled their wealth into the greatest concentration of temples on Earth.
One temple, Preah Khan, constructed in 1191, contained 60t of gold. Its value today would be about £2bn ($3.3bn).
But despite the city's immense wealth, trouble was brewing.
At the same time that Angkor's temple-building programme peaked, its vital hydraulic network was falling into disrepair - at the worst possible moment.
The end of the medieval period saw dramatic shifts in climate across south-east Asia.
Tree ring samples record sudden fluctuations between extreme dry and wet conditions - and the lidar map reveals catastrophic flood damage to the city's vital water network.
With this lifeline in tatters, Angkor entered a spiral of decline from which it never recovered.
In the 15th Century, the Khmer kings abandoned their city and moved to the coast. They built a new city, Phnom Penh, the present-day capital of Cambodia.
Life in Angkor slowly ebbed away.
Angkor Wat
When Mouhot arrived he found only the great stone temples, many of them in a perilous state of disrepair.
Nearly everything else - from common houses to royal palaces, all of which were constructed of wood - had rotted away.

The vast metropolis that once surrounded the temples had been all but devoured by the jungle.
Watch the first episode of Jungle Atlantis on Thursday 25 September at 20:00 BST on BBC Two, or catch it later on the BBC iPlayer. The programme was made in association with The Smithsonian Channel, which will be transmitting both episodes in the US on 5 October under the title Angkor Revealed.

Tuesday, September 23, 2014

Butterflies Take New York: September 21, 2014

  Climate Change March

The news reports say 310,000 people filled the streets of New York, demanding action on climate change. Not all of those people were human. There were birds, fish, mermaids, sunflowers, trees, and more than one Mother Earth and Mr. Death. Some species who couldn't make it in person, like tapirs, sent human ambassadors.

The people who did look human looked like all sorts of human. Indigenous people led the march, wearing gorgeous regalia, drumming and dancing. Great numbers came in from “front-line communities” like Indonesia and poor parishes in New Orleans, the communities least responsible for climate change yet most affected by floods, droughts, and hurricanes. Young people came to fight for their futures. Old people came to fight for their grandchildren.

Some of us have been waiting 45 years to see what we saw in New York: activists for social justice, peace, and the environment joining forces. Out of countless splinter groups, the Movement has finally pulled itself back together. And not a moment too soon.

Fox “news” and Koch-funded “think tanks” might still deny the existence of catastrophic and accelerating climate change, or the fact that humans have caused it. But nearly all scientists and a growing majority of ordinary people understand what's going on. It scares us so badly that our instinct for survival is kicking in.
We are not threatened only as nations or ethnic groups. We are in danger as a species. For the first time in our history, we must identify ourselves most strongly as humans – a species as vulnerable to extinction as whales and butterflies – if we're going to overcome our own deadly mistakes.

The Vermont collective Bread and Puppet performed some vivid street theater to get this point across. First came dozens of people dressed as caribou, with branches for antlers. Behind them loomed a huge Tar Sands puppet, with black wings appropriately made of garbage-bag plastic. Behind that puppet came Death.

Whenever the march stopped, the troupe blew horns to signal the advance of Tar Sands. The caribou fell cowering to the street. Death seemed triumphant; its minions danced on stilts.

Then the horns blew once more, and from nowhere came the Butterflies Against Climate Change: hurrah! They flew through the crowd, revived the caribou, and defeated the forces of destruction.

So okay, butterflies aren't going to save us. But think of them as representing creativity, the winged aspect of the human spirit, and this fable makes sense.

The more we know, the more frightened we get. Our culture is so deeply rooted in greed, violence, and exploitation. So much needs to change. Our leaders get their power from the way things are, which doesn't motivate them to change things. It's hard not to despair.

That's why this march was so necessary. We desperately need to believe that there is enough creativity, enough spiritual power, enough wisdom and skill in the great mass of “ordinary” people, to save humanity from the mess we have made.

On the last day of summer, hundreds of thousands of people demonstrated these qualities in New York City. New Yorkers – not known for their belief in unicorns – smiled and waved and flashed peace signs, hung banners from their balconies, and joined the mermaids and the sunflowers in the street.

So get in touch with your inner butterfly, and stay tuned. The struggle of our lifetimes is just beginning.

Monday, September 22, 2014