21 September 2019 | New Scientist | 9ALFRED-WEGENER-INSTITUT / MARIO HOPPMANNHow we can fight climate change
Christiana Figueres tells Adam Vaughan
newscientistlive.com>three decades. Researchers have
gone further back in time by
working out the glacier’s depths
using photos taken from a balloon
in 1909, and comparing them with
photos taken from a helicopter
more recently (see bottom left).
The lift and the steps down to
the shrinking glacier will soon be
dismantled if plans by ski-lift firm
Compagnie du Mont Blanc go
ahead. It hopes to move access
to the glacier 500 metres up the
valley, and build an educational
centre focused on climate change.
“It should allow us to dig a new
cave in a place where scientists
think there should still be some
ice in the next 20 years, even with
the most pessimistic scenarios,”
says Mathieu Dechavanne at
Compagnie du Mont Blanc.
In this area, mountaineers
are seeing the changes up close.
“Eighteen years ago, people used
to ask ‘have you seen evidence of
climate change?’ They don’t ask
that anymore, because it’s clear
there is,” says Andy Perkins, a
British mountain guide who has
guided climbers here since 2001.
Warming is leading to more
rockfall and thawing permafrost,
causing havoc with infrastructure,
he says. “You have to take greater
care because there is no normal
anymore,” says Perkins.
In August, Perkins took a
client on the Cosmiques Arête,
a route above Chamonix that is
considered stable. A day later,
a large piece of rock fell from it.
A recent study of 95 Mont Blanc
massif climbing itineraries from
a famous 1973 book found that all
but two of the routes have been
affected by climate change.
Becky Coles, part of an
all-female team midway through
climbing all the 4000-metre peaks
in the Alps, found the heatwave in
June closed several route options.
It is hard to show rockfall isThe biggest scientific project
ever to take place in the Arctic
is about to kick off. This week,
a ship is set to begin drifting in
the sea ice off Siberia, where it
will become locked in the ice
for months of the Arctic winter.
The Polarstern icebreaker
is due to depart from Norway
on 20 September and is part
of MOSAIC, an epic endeavour
that will involve some 600
scientists studying climate
change, Arctic wildlife and
more over the course of a year.
Winter sea ice in the
Arctic is too thick even for
icebreakers to penetrate.
“It doesn’t make sense to
fight the ice, rather we are
going to work with it,” says the
expedition’s leader, Markus
Rex of the Alfred Wegener
Institute for Polar and Marine
Research in Germany.
The Polarstern, loaded with
scientific equipment, fuel and
food, will be supported by a
fleet of four other icebreakers.
For half a year, the ice will
be impenetrable, so a runway
on the ice will operate to fly
in supplies.The behaviour of the
region’s rapidly declining
sea ice, which is expected to
disappear entirely over
summer in coming decades
because of climate change,
has been well-studied in
summer. But for winter, there
is little data beyond satelliteimages and basic temperature
records from ocean buoys,
says Rex.
The observations from the
Polarstern should help build
better models of climate
change. Rex says some models
predict that the Arctic will
warm by 5°C compared with
pre-industrial temperatures by
2100 but others predict 15°C
of warming. The range is huge
and needs narrowing, he says.
Donald Perovich from
Dartmouth University in
New Hampshire, who will be
aboard the Polarstern, says
the mission should also tell
us more about Arctic snow:
where it is, how it builds up in
winter and melts in summer,
and how it is blown around.
The mission should also
reveal more about how the
bottom of sea ice melts.
“It’s the biggest sea ice
experiment ever, by a large
margin,” says Perovich. “The
number of countries, the
number of scientists, the
number of icebreakers. It’s a
once-in-a-lifetime opportunity.”Scientists to be stranded
in the Arctic sea iceThe Polarstern icebreaker
is about to set out on an
unprecedented mission“It’s the biggest sea
ice experiment ever.
A once-in-a-lifetime
opportunity”across the board and, since 1960,
the rate at which they are losing
ice has increased. A leaked
draft of a report from the
Intergovernmental Panel on
Climate Change (IPCC) on our
planet’s oceans and ice warns that,
this century, melting glaciers will
“first give too much water and
then too little”.
Many places mentioned in the
IPCC report will seem remote to
some people, but the Mer de Glace
and nearby Argentière glacier are
in the heart of Europe, next to
Chamonix, a holiday destination
visited by millions every year.
Tourists can see the effects
clearly. The steps down to the Mer
de Glace are punctuated by “level
of the glacier” signs from 1985
through to 2015, the year the world
agreed the Paris accord to avert
dangerous global warming.
At the ice cave carved in the
glacier, white sheets have been laid
atop the ice to slow the melting.
Sébastien Payot tells me he is
running out of ways to adapt.
Since 1946, his family’s business
has carved a cave here for tourists
every year. But this year, the
diggers encountered a spit of
rock, indicating that they are
nearing the bottom of the glacier.
He fears that the ice’s retreat
means next year’s cave will be
the last. “It’s a barometer of
global warming,” he says.
Recent measurements
by Christian Vincent of the
University of Grenoble show that
the Mer de Glace and Argentière
glacier, France’s second greatest
glacier, have both lost around
800 metres in length in the past
800m
France’s two largest glaciers
have both lost this much of their
lengths over the past 30 years