How to grow your own glacier - M Jackson

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In the 13th century, Genghis Khan embarked on a mission to take over Eurasia, swiftly conquering countries and drawing them into his empire. But, legend has it that there was one obstacle that even he couldn't overcome: a towering wall of ice, grown by locals across a mountain pass. M Jackson explores the ancient methods of growing glaciers and how they can be used to combat climate change.

Lesson by M Jackson, directed by Artrake Studio.

In the 13th Century,

Genghis Khan embarked on a mission
to take over Eurasia,

swiftly conquering countries and drawing
them into his expanding Mongol Empire.

With his vast armies he became almost
unstoppable.

But, legend has it that there was
one obstacle

that even the impressive Khan couldn’t
overcome:

A towering wall of ice,

grown by locals across a mountain pass

to stop the Khan’s armies from
invading their territory.

No one knows how historically accurate
that particular story is,

but remarkably, it draws on fact:

For centuries, in the Karakoram
and Himalayan mountain ranges,

people have been growing glaciers
and using these homemade bodies of ice

as sources of drinking water and
irrigation for their crops.

But before we get to that fascinating
phenomenon,

it’s important to understand the
difference between

glaciers that grow in the wild,

and those that humans create.

In the wild,

glaciers require three conditions to grow:

Snowfall, cold temperatures, and time.

First, a great deal of snow falls and
accumulates.

Cold temperatures then ensure that the
stacked up snow

persists throughout the winter, spring,
summer, and fall.

Over the following years, decades,
and centuries,

the pressure of the accumulated snow

transforms layers into highly compacted
glacial ice.

Artificially growing a glacier,

however, is completely different.

At the confluence of three great
mountain ranges,

the Himalayas, Karakoram, and Hindu Kush,

some local cultures have believed for
centuries that glaciers are alive.

And what’s more,

that certain glaciers can have different
genders including male and female.

Local Glacier Growers ‘breed’ new glaciers
by grafting together—or marrying—

fragments of ice from male and
female glaciers,

then covering them with charcoal,
wheat husks, cloths, or willow branches

so they can reproduce.

Under their protective coverings,

these glacierets transform into fully
active glaciers

that grow each year with
additional snowfall.

Those then serve as lasting
reserves of water

that farmers can use
to irrigate their crops.

These practices have spread
to other cultures,

where people are creating their own
versions of glaciers

and applying them to solve serious
modern challenges around water supplies.

Take Ladakh, a high-altitude desert region
in northern India.

It sits in the rain shadow of the
Himalayas

and receives on average fewer than ten
centimeters of rain per year.

As local glaciers shrink because
of climate change,

regional water scarcity is increasing.

And so, local people have started growing
their own glaciers

as insurance against this uncertainty.

These glaciers come in two types:
horizontal, and vertical.

Horizontal glaciers are formed when
farmers redirect glacier meltwater

into channels and pipes,

then carefully siphon it off into a series
of basins made from stones and earth.

Villagers minutely control the release of
water into these reservoirs,

waiting for each new layer to freeze

before filling the basin
with another wave.

In early spring,

these frozen pools begin to melt,

supplying villagers with
irrigation for their fields.

Local people make vertical glaciers using
the meltwater

from already-existing glaciers
high above their villages.

The meltwater enters channels
that run downhill,

flowing until it reaches a crop site

where it bursts forth from a pipe pointing
straight into the air.

When winter temperatures dip,

this water freezes as it arcs
out of the pipe,

ultimately forming a 50 meter ice
sculpture called a stupa,

shaped like an upside-down ice cream cone.

This inverted form minimizes the amount
of surface area it exposes to the sun

in the spring and summer.

That ensures that the mini-glacier
melts slowly

and provides a reliable supply of water
to feed the farmers’ crops.

These methods may be ancient,

but they’re becoming more relevant

as climate change takes its
toll on our planet.

In fact, people are now growing their own
glaciers in many regions beyond Ladakh.

Swiss people, utilizing modern glacier
growing technology,

created their first stupa in 2016
in the Swiss Alps.

There are plans for over 100 more in
villages in Pakistan,

Kazakhstan, and Kyrgyzstan.

Perhaps one day we’ll be able to harness
our homegrown glaciers

well enough to build whole walls of ice–

this time not for keeping people out,

but to enable life in some of the planet’s
harshest landscapes.