Walking on snow is still possible on the
Mont Blanc,
But for how long?
Frenchman Loic Thivierge wants to be a
mountain guide, like his father before him.
From a young age he's learnt every
part of this glacier.
But now the landscape is changing before his very eyes.
Like here, on the Arête des Cosmiques ridge.
"We never thought things would fall here
and it all fell last September.
It used to be a very classic route and now we're
wondering whether we can even take it.
It's become dangerous and we're
wondering whether there's something even
bigger might break off, like the whole right side."
The more the glacier melts, the more the
rocky faces collapse.
The mountain is unstable,
and mountain guides are having
to adapt because tourism is on the rise
and more and more inexperienced climbers
want to tackle the routes.
"We used to be able to do some runs in the height of summer, on snowy trails,
and now that's finished.
We can only go in winter now.
Or not even at all. There are lots of
rocks you used to be able to climb but
now with the degradation of the
permafrost
that's unfathomable and almost dangerous.
So for us we're having to adapt, having
to deal with the situation that's
getting worse."
The millennia old permafrost acts like
cement between the rocky faces.
Of the 100 trails highlighted in a 1973 list, 
26 have been heavily affected and
three have disappeared altogether.
3,842 metres up, on the platform of the Aiguille du Midi,
this glaciologist is taking notes.
The mountain is rife with weather stations
and thermometers at various
altitudes, but collecting the data has to
be done in person.
"It's this active layer, this worsening of the 
thawing every year
that we believe to be the root 
cause of the rock faces collapsing.
Florence Magnin and her team at the Mont Blanc university are unequivocal on the issue.
Temperatures rise between 1 
and 1.5 degrees every decade.
At that rate in 30 to 40 years the
permafrost will have completely
disappeared at this altitude.
And the consequences are great for the 
million odd visitors
who visit the site every
year.
"Obviously there'll be an increase in instability. We're already noticing that, with bigger parts
falling off during hot summers.
And we're also noticing that during summer heatwaves
like in 2015 or 2003 there are lots of collapses.
So there's an increase in both the
frequency and the amount of collapses."
Today Florence Magnin's partner is none
other than mountain guide president Olivier Grebert,
who started his career in 1986.
He says that collaboration between guides and glaciologists is vital.
"We work alongside scientists who are now able to give us early signs of potential events.
They're incapable of
telling us when and where,
but they can see if sand is collapsing or if 
water is dripping
in certain areas where it shouldn't be."
The face of tourism is also changing, this train takes tourists up 1,913 meters every day
to admire the 'Sea of Ice', a valley glacier 
which is also shrinking.
So much so that the  'Sea of Ice' now looks 
like a sea of stones.
Here too the rocky faces above the glacier
have been collapsing for years.
"We can see grayish zones where it's collapsed
recently because we can see the oxydated
parts and the parts which have recently
come apart, like on the Bonatti pillar here."
Today glaciologists like Luc Moreau,
have a new role: to raise awareness of global warming.
"Every day from June 15 to
September 15 there is a glaciologist
here witnessing the evolution of this
landscape, which changes permanently,
just like the rest of the planet: vegetation,
mountains, melting snow.
Here the water is collected by EDF 
to produce energy, hydroelectricity.
The glacier changes and loses mass.
We have to create stairs
because the grotto is still there."
To enter the ice grotto, tourists need to
walk down 152 steps.
Along the way, signs
chart the decline of ice levels.
Every spring engineers need to dig out a new
cavity even lower for access.
The inside is still magical but many tourists
notice the changes.
"I came when I was young with my parents, 
around 30 years ago
and it's true that there was 
a lot more snow on the glacier."
"We used to come
here to admire it, but now we just come
to see the extent of the damage."
"It's quite frightening to think of climate change
and the visible impact on
glaciers in France and across the world."
In 2017 a rocky mass of four million
cubic meters came loose in the Swiss Alps,
killing eight hikers and destroying
a local village in the process.
All glaciers are concerned.
Bad news for the
25,000 mountain climbers who make the
pilgrimage to Europe's highest peak
every year.
