to the bottom of the world
the highest driest windiest and yes coldest region on earth more arid than the sahara and in parts colder than mars
the ice of antarctica glows with a light so dazzling it blinds the unprotected eye early explorers rubbed cocaine in their eyes to kill the pain of it
the weight of the ice is such that the entire continent sags below sea level beneath its weight yet the ice of antarctica is a calendar of climate change
it records the annual rise and fall of greenhouse gases and temperatures going back before the onset of the last ice ages nowhere on earth offers us such a perfect record
and here scientists are drilling into the past of our planet to find clues to the future of climate change
this past january i traveled to a place called wais divide about six hundred miles from the south pole it is the best place on the planet many say to study the history of climate change
about forty five scientists from the university of wisconsin the desert researchinstitute in nevada and others have been working to answer an essential question about global warming
what is the exact relationship between levels of greenhouse gases and planetary temperatures it's urgent work
we know that temperatures are rising this past may was the warmest worldwide on record and we know that levels of greenhouse gases are rising too what we don't know
is the exact precise immediate impact of these changes on natural climate patterns winds ocean currents
their entire camp every item of gear was ferried eight hundred and eighty five miles from mcmurdo station the main u s supply base on the coast of antarctica
wais divide itself though is a circle of tents in the snow
in blizzard winds the crew sling ropes between the tents so that people can feel their way safely to the nearest ice house and to the nearest outhouse
it snows so heavily there the installation was almost immediately buried indeed the researchers picked this site because ice and snow accumulates here ten times faster than anywhere else in antarctica
they have to dig themselves out every day
chilly commute
but under the surface
is a hive of industrial activity centered around an eight million dollar drill assembly
ten times a day they extract the ten foot long cylinder of compressed ice crystals that contain the unsullied air and trace chemicals laid down by snow season after season for thousands of years
it's really a time machine at the peak of activity earlier this year the researchers lowered the drill an extra hundred feet deeper into the ice every day and another three hundred and sixty five years deeper into the past
they inspect it they check it for cracks
for drill damage for spalls for chips
more importantly they prepare
for inspection and analysis by twenty seven independent laboratories in the united states and europe
who will examine it for forty different trace chemicals related to climate some in parts per quadrillion yes i said that with a q quadrillion
they cut the cylinders up into three foot sections for easier handling and shipment back to these labs some eight thousand miles from the drill site
each cylinder is a parfait of time
this ice formed as snow fifteen thousand eight hundred years ago when our ancestors were daubing themselves with paint and considering the radical new technology of the alphabet
bathed in polarized light and cut in cross section this ancient ice reveals itself as a mosaic of colors each one showing how conditions at depth in the ice have affected this
at depths where pressures can reach a ton per square inch
every year it begins with a snowflake
and by digging into fresh snow we can see how this process is ongoing today
this wall of undisturbed snow back lit by sunlight shows the striations of winter and summer snow layer upon layer
each storm scours the atmosphere washing out dust soot trace chemicals
and depositing them on the snow pack
year after year millennia after millennia
from this we can detect an extraordinary number of things we can see
most importantly
these cylinders and this snow trap air
each cylinder is about ten percent ancient air a pristine time capsule of greenhouse gases carbondioxide methane nitrous oxide all unchanged from the day that snow formed and first fell
and this is the object of their scrutiny but
don't we already know what we need to know about greenhouse gases why do we need to study this anymore don't we already know how they affect temperatures
don't we already know the consequenses of a changing climate on our settled civilization the truth is we only know the outlines
and what we don't completely understand we can't properly fix indeed we run the risk of making things worse consider
the single most successful international environmental effort of the twentieth century the montreal protocol in which the nations of earth banded together to protect the planet from the harmful effects of ozone destroying chemicals used
at that time in air conditioners refrigerators and other cooling devices we banned those chemicals and we replaced them
with other substances that molecule per molecule are a hundred times more potent as heat trapping greenhouse gases than carbon dioxide
this process requires
they have to in fact make sure this ice never gets warmer than about twenty degrees below zero otherwise the key gases inside it will dissipate so in the coldest place on earth
they work inside a refrigerator
as they handle the ice in fact they keep an extra pair of gloves warming in an oven
so that when their work gloves freeze and their fingers stiffen they can don a fresh pair they work against the clock and against the thermometer
so far they've packed up about four thousand five hundred ft of ice cores for shipment back to the united states this past season they manhandled them across the ice to waiting aircraft
the one hundred and ninth air national guard flew the most recent shipment of ice
back to the coast of antarctica where it was boarded onto a freighter
shipped across the tropics to california
unloaded put on a truck driven across the desert
was this planet 's last empty quarter the blind spot in our expanding vision of the world
early explorers sailed off the edge of the map
and they found a place where the normal rules of time and temperature seem suspended
here the ice seems a living presence
the wind that rubs against it gives it voice
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