1
00:00:29,680 --> 00:00:34,160
This white wilderness,
this emptiness, is the North Pole.


2
00:00:35,640 --> 00:00:39,440
I'm standing in the middle
of a frozen ocean.


3
00:00:40,560 --> 00:00:45,440
Beneath my feet and for
over 500 miles in every direction,


4
00:00:45,440 --> 00:00:48,280
there are several metres of ice.


5
00:00:49,520 --> 00:00:52,560
But something significant is
likely to happen here,


6
00:00:52,560 --> 00:00:54,520
at the North Pole, soon.


7
00:00:56,000 --> 00:00:59,640
Chances are that some time,
within the next few decades,


8
00:00:59,640 --> 00:01:05,960
perhaps even as soon as 2020,
there will be open water here


9
00:01:05,960 --> 00:01:09,640
for the first time
in human recorded history.


10
00:01:11,920 --> 00:01:16,000
The Arctic
and Antarctic are changing.


11
00:01:16,000 --> 00:01:20,120
Enormous masses of ice that have been
frozen for thousands of years


12
00:01:20,120 --> 00:01:22,240
are breaking apart and melting away.


13
00:01:35,800 --> 00:01:40,280
Ice scientists are going to
extremes to find out exactly


14
00:01:40,280 --> 00:01:41,680
what's going on.


15
00:01:41,680 --> 00:01:44,160
For them, these are exciting times.


16
00:01:45,760 --> 00:01:48,200
But the transformation that's being
seen here will be felt


17
00:01:48,200 --> 00:01:50,880
far beyond the polar wilderness.


18
00:01:57,280 --> 00:01:58,440
In this programme,


19
00:01:58,440 --> 00:02:03,080
I'll be trying to understand what
these changes mean, not just to the


20
00:02:03,080 --> 00:02:08,080
wildlife and people that live around
the Poles, but for the whole planet.


21
00:02:19,960 --> 00:02:24,080
I'm starting my journey in the
Arctic, the far north of our planet.


22
00:02:28,240 --> 00:02:31,560
It's still very cold
outside by most people's standards,


23
00:02:31,560 --> 00:02:34,760
but the Arctic has been warming fast,


24
00:02:34,760 --> 00:02:37,560
twice as fast as the rest
of our planet.


25
00:02:37,560 --> 00:02:41,080
My first mission is to find out
what effect


26
00:02:41,080 --> 00:02:43,720
that's having on the animals.


27
00:02:43,720 --> 00:02:46,640
Although first, we have to find them.


28
00:02:46,640 --> 00:02:49,440
It's April in Svalbard.


29
00:02:49,440 --> 00:02:52,800
We are 1,000 miles
north of the Arctic Circle,


30
00:02:52,800 --> 00:02:55,400
in search of the region's
top predator.


31
00:03:06,080 --> 00:03:10,040
We need to travel away from the land
and out over the frozen sea.


32
00:03:17,040 --> 00:03:19,320
There's some tracks
right beneath us.


33
00:03:25,360 --> 00:03:26,520
Over there.


34
00:03:29,760 --> 00:03:32,640
I'm with a Norwegian team,


35
00:03:32,640 --> 00:03:36,440
which is giving the polar bears of
Svalbard their yearly health check.


36
00:03:39,800 --> 00:03:41,120
She's under us now.


37
00:03:42,160 --> 00:03:43,960
I'll come round for a clean shot.


38
00:03:50,000 --> 00:03:53,640
The team works together to
give an anaesthetic injection


39
00:03:53,640 --> 00:03:56,280
from a dart gun without hurting
the bear.


40
00:03:57,920 --> 00:03:59,760
It takes tremendous skill.


41
00:04:04,120 --> 00:04:05,720
Ah, you've got it.


42
00:04:10,640 --> 00:04:13,360
I'll just back off
until she's asleep.


43
00:04:23,520 --> 00:04:25,920
Nobody likes to see a magnificent


44
00:04:25,920 --> 00:04:30,720
animal like a polar bear lolling
about unconscious on the ice,


45
00:04:30,720 --> 00:04:33,040
but it's only by darting them


46
00:04:33,040 --> 00:04:35,240
in this way and keeping check on them


47
00:04:35,240 --> 00:04:37,800
year after year,
that we can be sure we know


48
00:04:37,800 --> 00:04:42,080
what is happening to them and the
population of polar bears as a whole.


49
00:04:43,560 --> 00:04:46,920
Over the last 30 years,
many teams have been seeing


50
00:04:46,920 --> 00:04:50,720
the condition of their local bears
deteriorate.


51
00:04:50,720 --> 00:04:52,440
Although not every bear is suffering.


52
00:05:02,640 --> 00:05:10,600
How much? 96, there.


53
00:05:05,640 --> 00:05:10,600
And 102 here, so that's 197, yeah.


54
00:05:10,600 --> 00:05:11,640
Is that good?


55
00:05:13,720 --> 00:05:16,480
It's not too bad,
it's a bit above average.


56
00:05:16,480 --> 00:05:19,280
So she's a bear in a good condition
for Svalbard.


57
00:05:19,280 --> 00:05:25,720
The trouble is that if this was
underweight, she would be in trouble.


58
00:05:25,720 --> 00:05:30,520
Not only from her own point of view,
but from the point of her cubs,


59
00:05:30,520 --> 00:05:34,280
because an underweight female
gives birth to underweight cubs


60
00:05:34,280 --> 00:05:38,000
and underweight cubs have a great
problem of surviving


61
00:05:38,000 --> 00:05:41,600
their difficult first year
in these circumstances.


62
00:05:43,640 --> 00:05:47,960
It can be minus 40 degrees Centigrade
when polar bear cubs emerge


63
00:05:47,960 --> 00:05:50,160
at the start of the Arctic spring,


64
00:05:50,160 --> 00:05:52,640
from their dens where they were born.


65
00:06:05,000 --> 00:06:07,760
This mother hasn't
eaten for half a year.


66
00:06:09,840 --> 00:06:14,120
She and her cubs need to fatten up
fast over the next few months and


67
00:06:14,120 --> 00:06:18,480
their chances of survival depend on
what's happening beneath their feet.


68
00:06:22,520 --> 00:06:25,680
These polar bears aren't walking
on land.


69
00:06:25,680 --> 00:06:29,280
They're roaming across the frozen
surface of the sea.


70
00:06:32,880 --> 00:06:35,240
And the bear's food lives
under the ice.


71
00:06:48,800 --> 00:06:52,960
Ringed seals are hunted
by polar bears.


72
00:06:54,120 --> 00:07:00,160
In fact, in some parts,
polar bears eat almost nothing else.


73
00:07:00,160 --> 00:07:05,280
So, it's very understandable that
this mother ringed seal...


74
00:07:06,680 --> 00:07:10,640
..who's looking at me now,
should be a little apprehensive.


75
00:07:14,360 --> 00:07:18,080
That pup of hers is only about
three or four days old...


76
00:07:20,440 --> 00:07:25,760
..and the pup won't be able to swim
for another two or three days.


77
00:07:27,800 --> 00:07:31,880
Seals have good reason to be
nervous around their holes.


78
00:07:31,880 --> 00:07:34,960
They need the holes to breathe
when the sea is frozen,


79
00:07:34,960 --> 00:07:37,240
but this makes them easy to find.


80
00:07:39,320 --> 00:07:44,880
Polar bears can sniff out seal holes,
even if they're covered in snow.


81
00:07:51,200 --> 00:07:53,560
Spring is the best hunting season.


82
00:07:56,080 --> 00:07:59,120
This mother's found a food store
under the snow


83
00:07:59,120 --> 00:08:01,960
that was probably made
by an Arctic fox.


84
00:08:03,880 --> 00:08:05,840
It's a time of plenty now,


85
00:08:05,840 --> 00:08:08,800
but the bear family need to make
the best of it


86
00:08:08,800 --> 00:08:12,120
because the good times are about
to come to an end.


87
00:08:17,480 --> 00:08:18,920
As the weather warms,


88
00:08:18,920 --> 00:08:23,480
the ice beneath the bears' feet
starts to break up and then melt.


89
00:08:23,480 --> 00:08:28,240
And as the ice dwindles, so do the
bears' chances of a successful hunt.


90
00:08:31,520 --> 00:08:36,480
Most of the ice is lost over these
shallow coastal waters,


91
00:08:36,480 --> 00:08:37,920
where most of the seals live.


92
00:08:43,440 --> 00:08:47,760
It's now summer and these bears
have a choice - take their chances


93
00:08:47,760 --> 00:08:51,800
on the shrinking ice floes,
or make for the safety of the land.


94
00:08:57,160 --> 00:08:58,960
It's a case of sink or swim.


95
00:09:07,000 --> 00:09:09,320
Bears have always gone
hungry in the summer,


96
00:09:09,320 --> 00:09:11,880
but the length of time
when there's enough ice for them


97
00:09:11,880 --> 00:09:16,440
to go hunting is getting shorter and
shorter, across much of the Arctic.


98
00:09:19,840 --> 00:09:23,160
This is hitting cubs
particularly hard,


99
00:09:23,160 --> 00:09:27,680
because they can't survive for as
long without feeding as their mother.


100
00:09:29,320 --> 00:09:33,200
Cubs that were born
underweight are at the greatest risk.


101
00:09:42,800 --> 00:09:46,720
This mother and her cubs may well
not get another meal


102
00:09:46,720 --> 00:09:49,640
until the sea freezes again
in winter.


103
00:09:49,640 --> 00:09:54,400
There's not much to eat on land and
the fact is that the longer the cubs


104
00:09:54,400 --> 00:09:58,920
have to wait until the ice returns,
the more likely they are to die.


105
00:10:02,200 --> 00:10:06,200
Longer summers with no ice
are probably the main reason why


106
00:10:06,200 --> 00:10:09,120
many polar bear populations
are dropping.


107
00:10:17,400 --> 00:10:21,480
To help monitor bears into the
future, this female is being fitted


108
00:10:21,480 --> 00:10:24,200
with a radio collar to track
her movements.


109
00:10:28,520 --> 00:10:31,720
It's an extraordinary sensation to be


110
00:10:31,720 --> 00:10:34,640
so close to such a powerful animal.


111
00:10:34,640 --> 00:10:37,800
With luck, carrying that collar,


112
00:10:37,800 --> 00:10:40,120
she will have more years to go yet...


113
00:10:41,320 --> 00:10:43,960
..and be telling us a great deal


114
00:10:43,960 --> 00:10:46,440
about herself and the rest


115
00:10:46,440 --> 00:10:49,040
of the race of polar bears, as they


116
00:10:49,040 --> 00:10:51,640
face this very uncertain future.


117
00:10:59,040 --> 00:11:02,160
The future of the ice cover on
the sea isn't just


118
00:11:02,160 --> 00:11:03,680
an issue for the animals.


119
00:11:03,680 --> 00:11:06,000
It's a big concern for the people


120
00:11:06,000 --> 00:11:07,600
who live in the Arctic


121
00:11:07,600 --> 00:11:09,960
and travel across the ice every day.


122
00:11:18,520 --> 00:11:23,000
David Iqaqrialu is an Inuit
from the village of Clyde River


123
00:11:23,000 --> 00:11:24,600
in the Canadian Far North.


124
00:11:30,600 --> 00:11:35,160
There are very few roads up here,
so David and his community,


125
00:11:35,160 --> 00:11:39,160
like most Inuit people, have always
travelled across the frozen sea.


126
00:11:41,080 --> 00:11:45,720
Dog sleds are the safest way to
get around because the dogs feel


127
00:11:45,720 --> 00:11:48,480
thin ice underfoot and won't lead
travellers into trouble.


128
00:11:52,240 --> 00:11:54,680
Old-timers, like David,
know the ice is as well as we know


129
00:11:54,680 --> 00:11:57,440
the streets in our local
neighbourhood.


130
00:12:01,160 --> 00:12:02,360
Every spring,


131
00:12:02,360 --> 00:12:06,280
cracks have always formed in
the same places at the same time.


132
00:12:07,720 --> 00:12:12,040
It's going to be big very soon.
After two weeks maybe...


133
00:12:13,600 --> 00:12:15,800
..it will be more open.


134
00:12:17,160 --> 00:12:21,120
But now, cracks are appearing
where they never did before.


135
00:12:21,120 --> 00:12:25,480
So, David and his friend,
Laimikie, have taken on a new job.


136
00:12:27,160 --> 00:12:30,520
They are using special GPS units
to record the position


137
00:12:30,520 --> 00:12:33,120
of new cracks or weak ice.


138
00:12:35,320 --> 00:12:37,080
These findings will be used


139
00:12:37,080 --> 00:12:39,080
by locals for their own safety,


140
00:12:39,080 --> 00:12:41,400
but they're also being studied
by ice scientists,


141
00:12:41,400 --> 00:12:46,520
who want to predict how the ice
will change in years to come.


142
00:12:46,520 --> 00:12:48,800
THEY SPEAK THEIR NATIVE LANGUAGE


143
00:12:53,320 --> 00:12:57,800
The Inuit are keen to know what
the future holds too


144
00:12:57,800 --> 00:13:00,640
because they've seen
with their own eyes the changes


145
00:13:00,640 --> 00:13:03,200
that the scientists have seen
from space.


146
00:13:05,000 --> 00:13:07,920
This satellite photo from 1980
shows the Arctic Ocean


147
00:13:07,920 --> 00:13:12,800
at the end of the summer,
when ice cover is at its minimum.


148
00:13:12,800 --> 00:13:17,480
Since then, there's been a 30%
drop in the area covered by ice.


149
00:13:20,120 --> 00:13:24,960
But these images can't tell us about
changes to the most important factor,


150
00:13:24,960 --> 00:13:27,600
the thickness of the ice.


151
00:13:31,200 --> 00:13:33,560
Measuring thickness
across the whole ocean


152
00:13:33,560 --> 00:13:36,440
was beyond scientists for many years,


153
00:13:36,440 --> 00:13:39,880
until help came
from an unexpected source.


154
00:13:56,920 --> 00:14:01,640
The Arctic Ocean is of huge military
importance, as it's the shortest


155
00:14:01,640 --> 00:14:03,680
route between North America
and Russia.


156
00:14:09,400 --> 00:14:13,880
Since the late 1950s, British,
US and Russian submarines


157
00:14:13,880 --> 00:14:17,120
have been patrolling
the Arctic Ocean.


158
00:14:18,760 --> 00:14:23,160
But as well as looking out for
enemy activity,


159
00:14:23,160 --> 00:14:26,040
they've also been measuring
the thickness of the ice,


160
00:14:26,040 --> 00:14:28,520
critical when looking for
a place to surface.


161
00:14:32,160 --> 00:14:35,280
When scientists got permission to
look at the submarine crew's records,


162
00:14:35,280 --> 00:14:39,520
they discovered that the ice
has been thinning fast.


163
00:14:39,520 --> 00:14:42,760
In fact, it's nearly
halved in thickness since 1980.


164
00:14:47,200 --> 00:14:49,240
Across most of the Arctic Ocean,


165
00:14:49,240 --> 00:14:52,160
there are now just
a couple of metres of ice.


166
00:14:56,560 --> 00:15:00,960
It's so thin that it could melt away
almost entirely in the summertime,


167
00:15:00,960 --> 00:15:03,440
and that includes
the ice at the North Pole.


168
00:15:04,880 --> 00:15:08,000
If current trends continue,
then there will be


169
00:15:08,000 --> 00:15:09,920
open ocean here by summer's end,


170
00:15:09,920 --> 00:15:12,200
some time within
the next few decades.


171
00:15:15,640 --> 00:15:18,840
So, the days of the Arctic Ocean
being covered


172
00:15:18,840 --> 00:15:21,920
by a continuous sheet of ice
seem to have passed.


173
00:15:21,920 --> 00:15:25,360
Whether or not that's a good or
bad thing, of course,


174
00:15:25,360 --> 00:15:27,200
depends on your point of view.


175
00:15:30,760 --> 00:15:33,480
Nobody has had a better view of the
changes to the Arctic Ocean


176
00:15:33,480 --> 00:15:38,320
than the people of Barrow,
the most northerly town in Alaska.


177
00:15:38,320 --> 00:15:42,040
The people here have always
survived by hunting on the frozen sea


178
00:15:42,040 --> 00:15:44,640
and they celebrate this
at a festival every year.


179
00:15:46,840 --> 00:15:50,680
The blanket toss was once the best
way to spot distant animals to hunt,


180
00:15:50,680 --> 00:15:55,120
as lifelong resident
Lewis Brower explains.


181
00:15:55,120 --> 00:15:58,280
When we throw ourselves up into the
blanket, you know,


182
00:15:58,280 --> 00:16:02,120
you get that much more of an 'Ahh'
of seeing further and further out,


183
00:16:02,120 --> 00:16:04,800
so sometimes, you'll jump 15-20 feet
in the air,


184
00:16:04,800 --> 00:16:08,080
and hopefully, you're being caught
right back into the blanket.


185
00:16:10,080 --> 00:16:12,200
I'm OK!
THEY LAUGH


186
00:16:13,880 --> 00:16:16,560
But the old way of life
is under threat.


187
00:16:16,560 --> 00:16:21,400
When Lewis was young, the sea stayed
frozen to the horizon until July,


188
00:16:21,400 --> 00:16:24,400
and some ice remained
off-shore all summer.


189
00:16:24,400 --> 00:16:26,440
But now, it's breaking up in June


190
00:16:26,440 --> 00:16:30,720
and melting away completely
for two or three months.


191
00:16:30,720 --> 00:16:34,520
I used to go out on the ice all
the time at this time of the year,


192
00:16:34,520 --> 00:16:39,600
but we can't do that any more,
cos there's no more ice.


193
00:16:41,040 --> 00:16:45,440
Lewis can also see that the
loss of sea ice is affecting


194
00:16:45,440 --> 00:16:47,520
the animals he hunts for a living.


195
00:16:49,000 --> 00:16:52,720
Since 2007, something very strange
has been happening


196
00:16:52,720 --> 00:16:55,800
on this stretch of coastline,
close to Barrow.


197
00:16:59,520 --> 00:17:04,080
Mother walruses, confused by the lack
of ice, are crowding onto the land


198
00:17:04,080 --> 00:17:05,240
with their pups.


199
00:17:06,880 --> 00:17:09,280
This very tight crowding isn't normal


200
00:17:09,280 --> 00:17:12,680
and it's caused many youngsters
to be crushed to death.


201
00:17:15,280 --> 00:17:18,400
Many Arctic animals are threatened
by the changing conditions


202
00:17:18,400 --> 00:17:22,960
and that's also bad news
for the traditional hunters.


203
00:17:22,960 --> 00:17:26,880
But the ice loss could be good news
for some people.


204
00:17:30,920 --> 00:17:33,600
There are trillions of dollars' worth
of oil


205
00:17:33,600 --> 00:17:35,600
and gas under the Arctic Ocean.


206
00:17:35,600 --> 00:17:37,640
But the only way to get to them,


207
00:17:37,640 --> 00:17:41,920
until now, has been by building
expensive artificial islands,


208
00:17:41,920 --> 00:17:43,120
like this.


209
00:17:43,120 --> 00:17:44,880
But if the sea ice goes,


210
00:17:44,880 --> 00:17:48,040
it will be much easier to
drill for the huge riches below.


211
00:17:48,040 --> 00:17:52,400
So, the countries that surround
the Arctic are scrambling


212
00:17:52,400 --> 00:17:53,800
to stake their claims.


213
00:18:05,160 --> 00:18:10,640
This daring attempt by the Russians
to claim the disputed seabed


214
00:18:10,640 --> 00:18:13,960
at the North Pole in 2007 caused fury
among the competing countries


215
00:18:13,960 --> 00:18:17,600
and it's unlikely to be
the last such dispute.


216
00:18:19,600 --> 00:18:22,200
The Arctic has never been
so important


217
00:18:22,200 --> 00:18:24,800
and not just because of
its resources.


218
00:18:27,800 --> 00:18:29,160
The North-West passage,


219
00:18:29,160 --> 00:18:33,200
a legendary sea route around the
north of Canada and Alaska, cleared


220
00:18:33,200 --> 00:18:38,440
of ice in the summer of 2007 for the
first time since records began.


221
00:18:38,440 --> 00:18:41,320
This promises a much faster


222
00:18:41,320 --> 00:18:46,000
and cheaper shipping route between
the Atlantic and Pacific Oceans.


223
00:18:50,320 --> 00:18:53,280
And some wildlife could benefit
from an ice-free Arctic too.


224
00:18:58,440 --> 00:19:02,520
Bowhead whales are one of just
a few whales that can live


225
00:19:02,520 --> 00:19:05,640
year-round in the Arctic
because they have no dorsal fin.


226
00:19:07,840 --> 00:19:10,040
This means they can come up
for air in small spaces


227
00:19:10,040 --> 00:19:13,080
and travel easily under the ice.


228
00:19:14,680 --> 00:19:18,120
Their unique body shape used to
mean that the Arctic whales had


229
00:19:18,120 --> 00:19:22,320
the seas to themselves
for most of the year.


230
00:19:22,320 --> 00:19:25,200
But now, some cousins from down south
are moving in.


231
00:19:32,640 --> 00:19:35,960
Killer whales are now a much more
common sight in the Arctic.


232
00:19:35,960 --> 00:19:40,600
Their tall fins make it difficult
for them to travel under ice,


233
00:19:40,600 --> 00:19:44,640
but the longer summers mean they can
travel much further north


234
00:19:44,640 --> 00:19:47,240
and make the most of
the rich Arctic seas.


235
00:19:54,120 --> 00:19:57,080
For animals and people,


236
00:19:57,080 --> 00:20:00,760
it will be those that can adapt who
will thrive in a changing Arctic.


237
00:20:09,920 --> 00:20:12,840
But the loss of sea ice isn't just
an issue for the Arctic,


238
00:20:12,840 --> 00:20:17,160
because the state of the ice affects
the climate of the whole planet.


239
00:20:20,240 --> 00:20:25,120
Because it's white, the ice reflects
up to 90% of the Sun's energy.


240
00:20:25,120 --> 00:20:28,600
This is called the albedo effect
and it's why


241
00:20:28,600 --> 00:20:32,840
we often see heat haze in the Arctic,
even when the air feels cold.


242
00:20:39,640 --> 00:20:43,560
The frozen Arctic Ocean
acts as a huge reflector,


243
00:20:43,560 --> 00:20:47,160
bouncing back the Sun's heat
into space.


244
00:20:47,160 --> 00:20:50,520
Throughout history, that has helped
to cool the planet,


245
00:20:50,520 --> 00:20:54,480
but when the ice melts,
it's a different story.


246
00:21:00,040 --> 00:21:05,720
Because sea water is dark,
it absorbs most of the Sun's heat.


247
00:21:05,720 --> 00:21:09,400
In the Arctic, this can trigger
a chain reaction, as the warming


248
00:21:09,400 --> 00:21:14,160
water melts more ice, exposing more
water to the Sun's heat.


249
00:21:19,720 --> 00:21:23,440
This cycle of warming, as huge areas
start to absorb rather than


250
00:21:23,440 --> 00:21:27,680
reflect heat, is the main reason why
the Arctic, a region the size


251
00:21:27,680 --> 00:21:32,120
of North America, is warming twice
as fast as the rest of the Earth.


252
00:21:37,400 --> 00:21:40,280
So, melting sea ice is a big issue.


253
00:21:40,280 --> 00:21:42,920
But there's another kind of ice
that could have an even more


254
00:21:42,920 --> 00:21:44,840
dramatic impact on our world.


255
00:21:46,200 --> 00:21:48,560
The ice that is found on land.


256
00:21:51,280 --> 00:21:53,400
This is fresh water ice,


257
00:21:53,400 --> 00:21:57,280
formed from thousands of years
of accumulated snowfall.


258
00:22:03,440 --> 00:22:09,360
This is the front of a glacier,
quite a small one, believe it or not.


259
00:22:09,360 --> 00:22:11,840
Glaciers are like rivers of frozen


260
00:22:11,840 --> 00:22:16,080
fresh water flowing
across the surface of the land.


261
00:22:16,080 --> 00:22:19,200
This one, like most polar glaciers,


262
00:22:19,200 --> 00:22:23,680
is flowing down from a vast
inland ice sheet.


263
00:22:23,680 --> 00:22:26,520
And it's what happens to those
ice sheets


264
00:22:26,520 --> 00:22:30,000
that could radically alter
the face of the planet.


265
00:22:31,280 --> 00:22:35,200
The Greenland ice sheet is by far
the largest in the Arctic.


266
00:22:35,200 --> 00:22:37,200
It's two miles thick in places


267
00:22:37,200 --> 00:22:40,360
and six times
the size of the United Kingdom.


268
00:22:47,680 --> 00:22:51,560
Every summer, some of the surface
of the ice sheet melts,


269
00:22:51,560 --> 00:22:55,120
forming sapphire blue lakes
of melt water.


270
00:22:56,680 --> 00:22:59,560
More and more of these lakes
have been forming


271
00:22:59,560 --> 00:23:02,400
as Greenland has warmed
over the last 20 years.


272
00:23:04,000 --> 00:23:07,880
This lake has grown over several
weeks and now it's overflowing,


273
00:23:07,880 --> 00:23:10,320
carving a deep channel
through the ice.


274
00:23:17,280 --> 00:23:20,400
A network of channels criss-crosses
the ice sheet,


275
00:23:20,400 --> 00:23:23,520
but many of them
come to an abrupt end.


276
00:23:34,760 --> 00:23:38,120
Huge holes, like this,
can open up quite suddenly,


277
00:23:38,120 --> 00:23:40,440
draining the melt water away.


278
00:23:51,520 --> 00:23:55,640
Alun Hubbard is a glaciologist,
studying the enormous power


279
00:23:55,640 --> 00:23:59,480
of these waterfalls,
which are known as moulins.


280
00:23:59,480 --> 00:24:03,960
We've got this amazing moulin
going off here today.


281
00:24:03,960 --> 00:24:08,680
The water's overflowing from the
lake, which is beginning to drain.


282
00:24:08,680 --> 00:24:14,400
Tonnes of water cascading down
this pipe that is, effectively,


283
00:24:14,400 --> 00:24:18,080
plummeting to the depths
of the ice sheet through


284
00:24:18,080 --> 00:24:20,160
over a kilometre of vertical ice.


285
00:24:27,640 --> 00:24:30,840
Alun is here to study where
the melt water goes


286
00:24:30,840 --> 00:24:34,040
and what effect it has on
the remaining ice.


287
00:24:34,040 --> 00:24:38,400
To do that, he needs to find a
moulin that has recently run dry.


288
00:24:44,720 --> 00:24:47,400
Just a week ago,
there was a three-mile long,


289
00:24:47,400 --> 00:24:50,240
ten-metre deep lake here.


290
00:24:50,240 --> 00:24:53,760
The weight of all that water
cracked the ice beneath


291
00:24:53,760 --> 00:24:58,280
and the late drained in just
a few hours with incredible force.


292
00:25:03,440 --> 00:25:07,360
Thousand-tonne ice boulders
were tossed about like dice.


293
00:25:14,440 --> 00:25:17,640
Alun's team have found the hole
down which the lake disappeared


294
00:25:17,640 --> 00:25:20,160
and they want to have a closer look.


295
00:25:20,160 --> 00:25:23,240
It's not a job for anyone
with a fear of heights.


296
00:25:30,040 --> 00:25:32,480
As you can see, it's dry up here,
but if you listen,


297
00:25:32,480 --> 00:25:34,040
you can hear the thunder of,


298
00:25:34,040 --> 00:25:36,800
there's a lot of water entering it
at some depth.


299
00:25:38,680 --> 00:25:43,480
Alun wants to place a sensor
deep into the moulin to discover


300
00:25:43,480 --> 00:25:45,200
how much water is flowing
through the ice.


301
00:25:51,400 --> 00:25:54,240
As they drop,
they travel back in time.


302
00:25:56,360 --> 00:26:00,480
30 metres down and they reach
ice formed from snow that fell


303
00:26:00,480 --> 00:26:03,200
10,000 years ago,
in the last Ice Age.


304
00:26:06,360 --> 00:26:11,320
When this lake drained and the plug
got pulled and the whole lot


305
00:26:11,320 --> 00:26:17,280
flushed down through here,
this ice sheet, it rose by a metre


306
00:26:17,280 --> 00:26:21,720
as that water accessed the bed
and forced, jacked up the ice sheet.


307
00:26:21,720 --> 00:26:23,840
So, we know that the water


308
00:26:23,840 --> 00:26:28,200
in this whole plumbing cavity
system, down here,


309
00:26:28,200 --> 00:26:30,120
we know that shoots straight
through that ice


310
00:26:30,120 --> 00:26:33,040
and actually hits
the bed of the ice sheet.


311
00:26:33,040 --> 00:26:36,160
We've hit the water,
I can see the water now.


312
00:26:36,160 --> 00:26:38,360
Great. Nice work.


313
00:26:41,280 --> 00:26:45,320
This daring experiment is
measuring how the water flowing under


314
00:26:45,320 --> 00:26:48,720
the ice sheet affects the speed
with which the glaciers


315
00:26:48,720 --> 00:26:51,400
flow from it, down to the sea.


316
00:26:51,400 --> 00:26:54,800
The theory is that the water is
acting as a lubricant.


317
00:26:54,800 --> 00:26:58,480
So, the more water there is,
the faster the glacier flows.


318
00:27:00,680 --> 00:27:04,880
To the naked eye, glaciers don't
appear to move at all.


319
00:27:04,880 --> 00:27:06,160
But move, they do.


320
00:27:08,400 --> 00:27:12,520
These unique time-lapse images were
captured over the last four years.


321
00:27:25,360 --> 00:27:29,160
Through long observations,
we now know that Greenland's ice


322
00:27:29,160 --> 00:27:34,280
is flowing down to the sea twice
as quickly as it was 20 years ago.


323
00:27:34,280 --> 00:27:37,640
The speed of the glaciers
affects our sea levels


324
00:27:37,640 --> 00:27:42,000
because when they reach the water,
they break apart into icebergs.


325
00:27:43,800 --> 00:27:45,800
Occasionally, a real mega-berg
is born.


326
00:27:55,720 --> 00:27:58,520
This is the Store Glacier
in May 2010.


327
00:28:54,840 --> 00:28:58,080
75 million tonnes of ice,
that had been sitting on land


328
00:28:58,080 --> 00:29:01,160
for thousands of years,
has broken away.


329
00:29:06,400 --> 00:29:09,560
Events like this have become
increasingly common,


330
00:29:09,560 --> 00:29:12,960
as Greenland's glaciers flow faster
into the sea.


331
00:29:25,680 --> 00:29:31,400
Every single one of these icebergs
raises the sea level a small amount.


332
00:29:31,400 --> 00:29:35,880
Scientists monitoring the ice sheet
predict that Greenland might add


333
00:29:35,880 --> 00:29:40,600
as much as a half metre to world sea
levels by the end of the century,


334
00:29:40,600 --> 00:29:44,320
enough to swamp many of
the world's low-lying islands.


335
00:30:06,240 --> 00:30:11,240
99% of the Arctic's fresh water ice
is in Greenland.


336
00:30:11,240 --> 00:30:15,600
It's a staggeringly big ice sheet,
but it's just a drop in the ocean


337
00:30:15,600 --> 00:30:19,600
compared to that at the southern end
of our planet.


338
00:30:27,600 --> 00:30:31,920
In Antarctica,
there is ten times more ice,


339
00:30:31,920 --> 00:30:35,240
by far the largest
concentration of ice on Earth.


340
00:30:40,480 --> 00:30:43,440
Our exploration
of the Antarctic only began


341
00:30:43,440 --> 00:30:45,480
a little over 100 years ago.


342
00:30:51,360 --> 00:30:55,320
The study of ice retreat here was
unwittingly begun


343
00:30:55,320 --> 00:30:59,080
on an expedition led by the great
early explorer Ernest Shackleton.


344
00:31:03,200 --> 00:31:08,640
In 1916, after their expedition boat
was crushed and sunk by ice,


345
00:31:08,640 --> 00:31:14,240
Shackleton and two companions set
off to summon help in a tiny boat.


346
00:31:17,040 --> 00:31:21,000
They sailed over 800 miles
across the Southern Ocean


347
00:31:21,000 --> 00:31:24,680
to the island of South Georgia,
on the edge of the Antarctic.


348
00:31:28,160 --> 00:31:32,120
Near starving and dressed in rags,
the three men


349
00:31:32,120 --> 00:31:35,600
walked across the ice sheet at the
centre of the island, knowing there


350
00:31:35,600 --> 00:31:39,280
was a whaling base on the opposite
coast where they could summon help.


351
00:31:47,280 --> 00:31:51,040
This team of Royal Marines is
re-tracing the steps


352
00:31:51,040 --> 00:31:54,520
of that journey in tribute
to Shackleton and his men.


353
00:31:56,320 --> 00:32:01,080
But for all their efforts, they can't
exactly copy the great walk


354
00:32:01,080 --> 00:32:02,360
because the ice is not as it was.


355
00:32:06,000 --> 00:32:08,560
A number of South Georgia's glaciers


356
00:32:08,560 --> 00:32:09,840
were photographed


357
00:32:09,840 --> 00:32:11,760
by Shackleton's cameraman.


358
00:32:11,760 --> 00:32:14,600
Frozen Planet saw a dramatic change


359
00:32:14,600 --> 00:32:17,360
when they returned 94 years later.


360
00:32:35,160 --> 00:32:40,080
Most of South Georgia's glaciers
have shrunk since Shackleton's time


361
00:32:40,080 --> 00:32:41,680
and most of that has happened


362
00:32:41,680 --> 00:32:44,480
since I first went to
the Antarctic 30 years ago.


363
00:32:46,040 --> 00:32:48,960
I've been to South Georgia
several times


364
00:32:48,960 --> 00:32:52,480
and seen how greatly the glaciers
there have changed.


365
00:32:56,720 --> 00:32:58,600
This photograph of a glacier


366
00:32:58,600 --> 00:33:00,600
reaching right down to the sea


367
00:33:00,600 --> 00:33:02,720
was taken just six years


368
00:33:02,720 --> 00:33:05,520
before I first visited in 1981.


369
00:33:06,720 --> 00:33:11,400
Now, that glacier has retreated
by 400 metres away from the beach.


370
00:33:16,680 --> 00:33:21,040
Temperatures in South Georgia have
risen sharply, but the Southern


371
00:33:21,040 --> 00:33:25,640
Hemisphere's most dramatic warming
has happened a little further south.


372
00:33:27,160 --> 00:33:30,800
In recent years, stronger winds
blowing over the Southern Ocean


373
00:33:30,800 --> 00:33:35,400
have brought warmer air to the 800
mile-long finger of land that forms


374
00:33:35,400 --> 00:33:38,920
the northern extremity
of the Antarctic continent.


375
00:33:44,920 --> 00:33:49,640
Here, on the Antarctic Peninsula, the
changing wind patterns have driven


376
00:33:49,640 --> 00:33:53,000
temperatures up by nearly
three degrees Centigrade


377
00:33:53,000 --> 00:33:54,520
over the last 50 years.


378
00:33:54,520 --> 00:33:58,360
Ten times the average rate
of the rest of the planet.


379
00:34:04,640 --> 00:34:09,240
The rapid warming is having
a big effect on the birdlife.


380
00:34:24,480 --> 00:34:29,160
The Adelie penguin is the most
southerly nesting of all penguins.


381
00:34:31,960 --> 00:34:35,160
And, like the polar bear,
up in the north,


382
00:34:35,160 --> 00:34:38,760
their lives are dependent
on the sea ice.


383
00:34:40,200 --> 00:34:43,320
Adelies spend their whole lives
near ice.


384
00:34:43,320 --> 00:34:45,960
These birds have spent
the winter feeding at the ice edge,


385
00:34:45,960 --> 00:34:48,440
but now it's spring


386
00:34:48,440 --> 00:34:52,800
and they've started a long trek
over the frozen sea towards land.


387
00:35:00,400 --> 00:35:05,560
They're heading for areas
of exposed rock, where they gather


388
00:35:05,560 --> 00:35:09,240
to breed, in colonies that can be
over 100,000 strong.


389
00:35:25,800 --> 00:35:28,800
But it seems that Adelies don't
find the conditions


390
00:35:28,800 --> 00:35:31,320
on the Peninsula
to their liking any more.


391
00:35:33,720 --> 00:35:38,200
17 years ago, when I was last
in the Antarctic, there were


392
00:35:38,200 --> 00:35:43,760
large colonies of Adelie penguins
all along the Antarctic Peninsula.


393
00:35:43,760 --> 00:35:49,000
Now, warming temperatures
have meant less sea ice


394
00:35:49,000 --> 00:35:52,200
and Adelie penguin numbers
are in decline.


395
00:36:01,200 --> 00:36:04,040
Many colonies have been
emptying fast.


396
00:36:08,280 --> 00:36:10,440
It may be that penguins are starving,


397
00:36:10,440 --> 00:36:14,320
or it may be that they're heading
south to colder climes


398
00:36:14,320 --> 00:36:17,320
where there's still plenty of ice
on the sea.


399
00:36:25,600 --> 00:36:29,920
But, as in the Arctic,
while ice-loving animals are feeling


400
00:36:29,920 --> 00:36:34,920
the heat, animals that like it
a bit more cosy are moving in.


401
00:36:42,960 --> 00:36:46,640
The bright orange beaks of Gentoo
penguins are a much more common sight


402
00:36:46,640 --> 00:36:49,440
on the Peninsula these days.


403
00:36:49,440 --> 00:36:51,680
I always used to know them
as residents


404
00:36:51,680 --> 00:36:54,960
of the slightly warmer islands
north of the Antarctic.


405
00:36:54,960 --> 00:36:57,200
But they've moved south in numbers.


406
00:36:58,720 --> 00:37:02,280
There are thought to be ten times
more Gentoos on the Peninsula now


407
00:37:02,280 --> 00:37:03,840
than just 30 years ago.


408
00:37:13,320 --> 00:37:16,040
The peninsula has warmed
a great deal,


409
00:37:16,040 --> 00:37:18,720
but the same is not true
further south.


410
00:37:23,760 --> 00:37:28,600
The Antarctic continent is smothered
by the world's greatest ice sheet.


411
00:37:29,760 --> 00:37:32,400
One and half times the size of
Australia


412
00:37:32,400 --> 00:37:34,280
and up to three miles thick.


413
00:37:37,400 --> 00:37:42,600
A staggering 75% of the Earth's
fresh water is locked up in this ice.


414
00:37:46,880 --> 00:37:52,960
Global sea levels would rise by some
60 metres if all this was to melt.


415
00:37:56,960 --> 00:38:01,080
But what chance is there of
that happening here in the coldest,


416
00:38:01,080 --> 00:38:02,800
most hostile place on Earth?


417
00:38:08,720 --> 00:38:13,560
The ice beneath me, up here
on top of the ice cap, is so thick


418
00:38:13,560 --> 00:38:18,400
that I am short of breath,
simply because of the altitude.


419
00:38:19,480 --> 00:38:22,200
This is midsummer


420
00:38:22,200 --> 00:38:27,640
and the average temperature is
some 20 degrees below freezing.


421
00:38:28,720 --> 00:38:31,640
And I can tell you it feels
much lower than that.


422
00:38:32,720 --> 00:38:37,280
And even the worst predictions
don't suggest


423
00:38:37,280 --> 00:38:42,320
that the air is going to warm enough
to melt the ice.


424
00:38:42,320 --> 00:38:46,000
But now, scientists are asking
a different question.


425
00:38:47,720 --> 00:38:51,800
Could the speed at which
the Antarctic ice flows off the land


426
00:38:51,800 --> 00:38:54,000
be increased by a warmer ocean?


427
00:38:55,680 --> 00:38:57,920
Where the ice sheet meets the sea,


428
00:38:57,920 --> 00:39:01,560
scientists are going to
extreme lengths to find out.


429
00:39:01,560 --> 00:39:02,760
Firing.


430
00:39:14,240 --> 00:39:17,720
Andy Smith works
for the British Antarctic Survey.


431
00:39:19,160 --> 00:39:22,960
What we have here is one kilogramme
of pentolite explosive.


432
00:39:22,960 --> 00:39:26,240
We're going to use this
to generate a shockwave


433
00:39:26,240 --> 00:39:29,400
and record the echoes that come back
from underneath the ice.


434
00:39:29,400 --> 00:39:30,920
Firing.


435
00:39:33,800 --> 00:39:37,080
Andy is particularly
interested in mapping


436
00:39:37,080 --> 00:39:39,200
the underside of the ice
around the coast.


437
00:39:40,840 --> 00:39:44,720
Because here,
it isn't resting on land.


438
00:39:44,720 --> 00:39:48,640
It's floating on sea water,
so if sea temperatures rise


439
00:39:48,640 --> 00:39:51,400
just a little,
it can be melted from below.


440
00:39:53,480 --> 00:39:55,840
Around the coast of Antarctica,


441
00:39:55,840 --> 00:40:00,440
the glaciers have flowed out across
the sea to form immense masses


442
00:40:00,440 --> 00:40:03,840
of floating fresh water ice,
called ice shelves.


443
00:40:08,120 --> 00:40:12,320
These freeze to the land around
them, sticking fast and acting


444
00:40:12,320 --> 00:40:16,200
like bathplugs, holding back the
flow of the glaciers into the sea.


445
00:40:19,400 --> 00:40:23,800
On the Antarctic Peninsula,
a one-degree sea temperature rise


446
00:40:23,800 --> 00:40:28,240
has helped to break apart seven major
ice shelves in the last 30 years.


447
00:40:29,920 --> 00:40:32,360
This is the Larsen B ice shelf,


448
00:40:32,360 --> 00:40:36,720
three times the size of Greater
London, breaking apart in 2002.


449
00:40:38,960 --> 00:40:42,520
Afterwards, the glaciers it had been
holding back


450
00:40:42,520 --> 00:40:45,200
started flowing
up to six times faster.


451
00:40:48,280 --> 00:40:51,960
In 2008, a much larger ice shelf
at the southern end


452
00:40:51,960 --> 00:40:55,040
of the peninsula started to break up.


453
00:40:56,120 --> 00:40:59,760
It's an enormous event
that's never been filmed before.


454
00:41:02,200 --> 00:41:04,760
Andy Smith is flying
down the Peninsula to study


455
00:41:04,760 --> 00:41:07,400
this phenomenon first hand.


456
00:41:08,440 --> 00:41:11,880
We're flying to a place called
Wilkins Ice Shelf.


457
00:41:11,880 --> 00:41:15,160
It's an ice shelf that,
over the last couple of years,


458
00:41:15,160 --> 00:41:19,320
has shown a very sudden
and dramatic break-up.


459
00:41:21,560 --> 00:41:24,520
The Wilkins Ice Shelf is
a two-hour long flight south


460
00:41:24,520 --> 00:41:27,920
from his research base,
but Andy can start to see


461
00:41:27,920 --> 00:41:33,120
the evidence of ice shelf break-up
a long way before he gets there.


462
00:41:33,120 --> 00:41:34,520
As we're heading further south,


463
00:41:34,520 --> 00:41:37,520
we can see more and more
icebergs in the ocean.


464
00:41:37,520 --> 00:41:39,880
And most of the big ones
will be ones


465
00:41:39,880 --> 00:41:42,480
that have broken off
the ice shelves in this area.


466
00:41:48,080 --> 00:41:50,720
Once we cross the mountains,
we should be able to see


467
00:41:50,720 --> 00:41:54,000
Wilkins Ice Shelf and then it's not
far then to the ice front, here,


468
00:41:54,000 --> 00:41:55,320
where it's collapsing.


469
00:42:07,480 --> 00:42:10,080
As Andy's team reaches
their destination,


470
00:42:10,080 --> 00:42:13,600
the scale of what's been happening
soon becomes clear.


471
00:42:13,600 --> 00:42:16,960
Here, for thousands of years,
an area the size of Yorkshire


472
00:42:16,960 --> 00:42:20,440
has been covered by a sheet of ice
200 metres thick.


473
00:42:25,520 --> 00:42:28,440
But now,
over half of that has broken apart.


474
00:42:42,680 --> 00:42:47,400
Andy has been studying
Antarctic ice for 25 years,


475
00:42:47,400 --> 00:42:50,480
but even he is blown
away by what he's seeing.


476
00:42:51,560 --> 00:42:55,240
Now, that is pretty awesome.
That is remarkable.


477
00:42:55,240 --> 00:42:59,760
The edge of the ice shelf has just,
kind of, disintegrated.


478
00:42:59,760 --> 00:43:01,800
Some of the big pieces look like


479
00:43:01,800 --> 00:43:04,160
they could be a mile or more
in size.


480
00:43:06,520 --> 00:43:10,040
It's almost like a, sort of,
a slow motion explosion.


481
00:43:10,040 --> 00:43:12,560
It all pushes outwards very quickly.


482
00:43:20,360 --> 00:43:24,800
Every one of these huge icebergs
will slowly drift out to sea.


483
00:43:29,800 --> 00:43:34,600
To study how fast that happens, Andy
needs to get closer to the action.


484
00:43:36,120 --> 00:43:39,960
We're going to look around and see
if we can find a place where


485
00:43:39,960 --> 00:43:42,520
we can land. And if we can, we'll be
able to put down an instrument


486
00:43:42,520 --> 00:43:45,840
that will help us monitor the big
icebergs that are breaking off


487
00:43:45,840 --> 00:43:47,360
as the ice shelf breaks up.


488
00:43:55,640 --> 00:43:59,040
Landing on an iceberg is another
first for Andy's team.


489
00:44:13,480 --> 00:44:17,440
This satellite transmitter will help
to track the continued break-up


490
00:44:17,440 --> 00:44:20,760
of this colossal ice shelf.


491
00:44:33,360 --> 00:44:37,840
The remainder of the Wilkins
looks set to break apart soon.


492
00:44:41,320 --> 00:44:45,440
It's the latest ice shelf to
disintegrate in a wave that's been


493
00:44:45,440 --> 00:44:46,800
travelling southwards,


494
00:44:46,800 --> 00:44:50,480
playing a major role in the loss
of ice from the Peninsula.


495
00:44:51,600 --> 00:44:56,880
Next in line, and already weakening
in places, are the ice shelves


496
00:44:56,880 --> 00:45:01,920
that hold back Antarctica's gigantic
continental ice sheet.


497
00:45:03,040 --> 00:45:07,360
And it would only take a small
corner of this to slide into the sea


498
00:45:07,360 --> 00:45:09,320
to have major global consequences.


499
00:45:12,560 --> 00:45:17,360
We've only started to see changes
in the Arctic and Antarctic recently.


500
00:45:17,360 --> 00:45:21,760
So, it's hard to predict exactly what
impact these changes will have.


501
00:45:21,760 --> 00:45:25,520
But we can see for ourselves
that these places are changing


502
00:45:25,520 --> 00:45:28,120
and on a scale that is hard
to ignore.


503
00:45:31,160 --> 00:45:36,000
The Poles, North and South,
may seem very remote,


504
00:45:36,000 --> 00:45:40,560
but what is happening here is likely
to have a greater effect upon us


505
00:45:40,560 --> 00:45:44,160
than any other aspect
of global warming.


506
00:45:44,160 --> 00:45:48,400
If the Arctic sea ice
continues to disappear,


507
00:45:48,400 --> 00:45:52,800
it will drive up the planet's
temperature more quickly.


508
00:45:52,800 --> 00:45:55,760
And the melting ice sheets could
contribute to a sea level rise


509
00:45:55,760 --> 00:45:59,840
of a metre, enough to threaten
the homes of millions of people


510
00:45:59,840 --> 00:46:03,320
around the world's coasts
by the end of the century.


511
00:46:04,720 --> 00:46:09,040
We've seen that the animals are
already adapting to these changes,


512
00:46:09,040 --> 00:46:16,000
but can WE respond to what is
happening now to the frozen planet?


513
00:46:53,600 --> 00:46:57,480
The increasing unpredictability
of the ice was a big issue


514
00:46:57,480 --> 00:47:02,160
for the Frozen Planet team, who spent
three years working on top of it.


515
00:47:09,600 --> 00:47:12,360
Whether on sea, land, lake or river,


516
00:47:12,360 --> 00:47:16,800
the state of the ice was the first
concern for most filming crews.


517
00:47:21,960 --> 00:47:28,080
Unexpected break-ups left many a
cameraman in need of a swift rescue.


518
00:47:28,080 --> 00:47:30,880
Sometimes, help came by boat,
and sometimes by air.


519
00:47:38,280 --> 00:47:41,960
I had a chance to see the changing
ice conditions for myself,


520
00:47:41,960 --> 00:47:44,000
when I visited the North Pole.


521
00:47:46,800 --> 00:47:51,640
I flew with the team to a temporary
camp that is set up every year in


522
00:47:51,640 --> 00:47:55,640
the centre of the frozen Arctic Ocean
to support expeditions to the Pole.


523
00:48:00,400 --> 00:48:04,400
I had never visited
the North Pole before,


524
00:48:04,400 --> 00:48:05,840
so this was a great highlight for me.


525
00:48:07,080 --> 00:48:10,160
But it was hard going
in temperatures of minus 40,


526
00:48:10,160 --> 00:48:12,360
so as soon as filming finished,
we flew south.


527
00:48:14,880 --> 00:48:18,440
Little did we know that
we had made it out just in time.


528
00:48:20,160 --> 00:48:24,760
We got back from the Pole camp
last night and I've just bumped into


529
00:48:24,760 --> 00:48:28,680
the Russian Commander,
who's just heard from the camp.


530
00:48:28,680 --> 00:48:33,760
And the news is that a little crack,
which I'd seen in the ice


531
00:48:33,760 --> 00:48:39,320
between our tent and the airstrip,
which was no more than an inch


532
00:48:39,320 --> 00:48:43,640
or so wide, has, overnight,
widened to 20 metres.


533
00:48:43,640 --> 00:48:47,080
Temporary break-ups,
caused by stormy weather


534
00:48:47,080 --> 00:48:50,520
and strong winds, have happened
before, but they've been getting


535
00:48:50,520 --> 00:48:54,400
more and more frequent over recent
years as the ice has got weaker.


536
00:48:59,040 --> 00:49:01,800
It was only swift action
by the staff that prevented


537
00:49:01,800 --> 00:49:05,120
a lot of valuable equipment
going in the drink.


538
00:49:11,880 --> 00:49:16,160
The biggest concern was that the
ice airstrip might break apart,


539
00:49:16,160 --> 00:49:19,440
but, luckily, it held
and everyone was able to evacuate


540
00:49:19,440 --> 00:49:21,320
when the weather improved.


541
00:49:25,720 --> 00:49:29,680
The Frozen Planet team's
clearest demonstration of the power


542
00:49:29,680 --> 00:49:31,840
and unpredictability of breaking ice


543
00:49:31,840 --> 00:49:36,480
came when they went to film the
melting of a frozen Canadian river.


544
00:49:36,480 --> 00:49:37,920
Producer Mark Linfield


545
00:49:37,920 --> 00:49:42,200
and researcher Matt Swarbrick have
travelled to the far North of Canada.


546
00:49:42,200 --> 00:49:44,120
Matt, when was the last time
we saw a car?


547
00:49:44,120 --> 00:49:46,240
I don't know, about three hours ago.


548
00:49:48,720 --> 00:49:51,920
They've driven through the vast
Northwest Territory on a mission


549
00:49:51,920 --> 00:49:55,680
to film the moment when
this frozen waterfall breaks apart.


550
00:49:59,520 --> 00:50:02,960
The break-up, when the frozen
river above the waterfall thaws


551
00:50:02,960 --> 00:50:07,600
and masses of water start to flow
again, can be a spectacular event.


552
00:50:07,600 --> 00:50:10,520
But predicting exactly when
it's going to break


553
00:50:10,520 --> 00:50:14,280
is the big challenge, if Mark and
Matt want to get the best shots.


554
00:50:16,560 --> 00:50:19,600
And they're not the only ones
who want to know.


555
00:50:19,600 --> 00:50:23,000
When the waterfall breaks,
it can flood the town of Hay River,


556
00:50:23,000 --> 00:50:27,840
just downstream, with
millions of tonnes of water and ice.


557
00:50:27,840 --> 00:50:31,560
Mark is taking advice
from the scientist Fay Hicks,


558
00:50:31,560 --> 00:50:34,960
who has the job of predicting
when the ice will break.


559
00:50:34,960 --> 00:50:38,360
What happens is, you get ice jams
form upstream and they start to dam


560
00:50:38,360 --> 00:50:39,440
up the water and it builds


561
00:50:39,440 --> 00:50:41,160
and builds and builds,
and that can let go,


562
00:50:41,160 --> 00:50:44,280
and that's a much bigger wave of
water, you know,


563
00:50:44,280 --> 00:50:45,960
than just the normal flow.


564
00:50:45,960 --> 00:50:48,880
So, it just depends upon how
dramatically it unfolds.


565
00:50:50,320 --> 00:50:54,000
Fay takes her research helicopter
to monitor the situation


566
00:50:54,000 --> 00:50:56,040
upstream of the waterfall.


567
00:51:04,880 --> 00:51:09,120
Just ten miles up river,
the ice is starting to break.


568
00:51:10,680 --> 00:51:14,600
The locals are concerned because
huge amounts of water can build up


569
00:51:14,600 --> 00:51:16,680
if these ice chunks dam the river,


570
00:51:16,680 --> 00:51:19,520
and that can lead to devastating
flooding in the town,


571
00:51:19,520 --> 00:51:21,120
when the dams burst.


572
00:51:21,120 --> 00:51:23,920
Sound of it's moving through
there now.


573
00:51:23,920 --> 00:51:25,560
Yes, got a shot.


574
00:51:25,560 --> 00:51:28,880
Using cameras and sonar to assess
the state of the river,


575
00:51:28,880 --> 00:51:31,720
Fay makes her best guess at
when this break-up will hit


576
00:51:31,720 --> 00:51:33,960
the waterfall just above the town.


577
00:51:33,960 --> 00:51:36,560
Now, guys, I think we have about
48 hours to go.


578
00:51:38,200 --> 00:51:42,680
Fay's prediction of the 24th April
is exciting news for the team.


579
00:51:45,720 --> 00:51:50,200
Upstream from here, it's already
starting to melt and Fay thinks that


580
00:51:50,200 --> 00:51:55,400
we may only have another one or two
days before this whole thing goes.


581
00:51:55,400 --> 00:51:58,160
Which is almost impossible
to imagine looking at it now,


582
00:51:58,160 --> 00:51:59,680
but that's what she says.


583
00:51:59,680 --> 00:52:02,960
With the break-up seemingly imminent,


584
00:52:02,960 --> 00:52:05,960
the team set up
their cameras in anticipation.


585
00:52:08,880 --> 00:52:11,880
Over the next 48 hours, the weather
warms to well above freezing,


586
00:52:11,880 --> 00:52:13,680
but there's no sign of the break-up.


587
00:52:13,680 --> 00:52:16,960
The team waits and waits and waits.


588
00:52:27,320 --> 00:52:30,480
Mark is concerned that the crew have
to return home soon, so


589
00:52:30,480 --> 00:52:32,520
he heads into town to get the advice


590
00:52:32,520 --> 00:52:35,680
of long-term resident Red McBrian.


591
00:52:35,680 --> 00:52:41,040
We just have to live with it and
take whatever evasive action we can.


592
00:52:41,040 --> 00:52:45,640
Red has had 50 years
of witnessing the power of the river.


593
00:52:45,640 --> 00:52:49,720
Well, we're hoping that she may
break up in two or three days.


594
00:52:49,720 --> 00:52:53,120
Oh, no, no, no, that's too soon.
Oh, no, no.


595
00:52:53,120 --> 00:52:57,160
Boys, you're looking at seven
or eight days


596
00:52:57,160 --> 00:53:01,960
before she breaks of any
significance.


597
00:53:01,960 --> 00:53:08,080
And if she breaks, she can jam
and hold up. She can be...


598
00:53:09,120 --> 00:53:13,200
She'd be down here probably
around the 5th or 6th May.


599
00:53:14,800 --> 00:53:19,080
The townspeople are on tenterhooks,
waiting for the big day,


600
00:53:19,080 --> 00:53:22,640
but another week goes by
before anything starts to happen.


601
00:53:34,280 --> 00:53:37,440
Finally, it seems that things
might be happening.


602
00:53:37,440 --> 00:53:39,520
We've just heard some cracks
from upstream,


603
00:53:39,520 --> 00:53:42,840
so, if we're lucky,
we might get some action.


604
00:53:42,840 --> 00:53:47,080
Seven o'clock, which gives us
two hours of light. Two hours.


605
00:53:47,080 --> 00:53:51,120
If it happens at night,
we're going to miss the whole thing.


606
00:53:52,640 --> 00:53:55,280
Sure enough,
the town is put on red alert


607
00:53:55,280 --> 00:53:59,720
that the river is about to break
in the middle of the night.


608
00:53:59,720 --> 00:54:02,320
They've just called a full
evacuation of the Eye Inn,


609
00:54:02,320 --> 00:54:05,480
where we're staying, and if we don't
move now, we're all going to be


610
00:54:05,480 --> 00:54:08,200
underwater and possibly get trapped
here for a few days.


611
00:54:09,240 --> 00:54:11,720
The team have to move out
and get up to the waterfall,


612
00:54:11,720 --> 00:54:15,920
hoping that it doesn't break
before it's light enough to film.


613
00:54:20,920 --> 00:54:24,680
Luckily, the Sun is up
before the main event begins.


614
00:54:24,680 --> 00:54:28,280
That is a serious amount of ice
coming around the corner.


615
00:54:39,480 --> 00:54:43,360
After weeks of waiting,
the sleeping giant of a river,


616
00:54:43,360 --> 00:54:47,720
we thought nothing was go to happen
and suddenly, look at this!


617
00:54:49,040 --> 00:54:52,360
This is what we're here for.
Unbelievable.


618
00:54:52,360 --> 00:54:55,280
Absolutely unbelievable. Holy BLEEP!


619
00:54:59,160 --> 00:55:01,600
The team is used to handling
multiple cameras,


620
00:55:01,600 --> 00:55:05,320
but they don't usually have to dodge
ten-tonne ice floes at the same time.


621
00:55:08,840 --> 00:55:11,760
As you can see, it's racing
over at unbelievable speed.


622
00:55:11,760 --> 00:55:15,120
The power, I just, if you were here
to feel this, it's a deep rumbling


623
00:55:15,120 --> 00:55:19,120
sound of the river, I can feel it up
through my feet.


624
00:55:19,120 --> 00:55:23,880
The power, I just can't imagine.
That could crush a house in no time.


625
00:55:23,880 --> 00:55:28,680
The team takes to the air to witness
the destruction that's unleashed.


626
00:55:28,680 --> 00:55:32,000
Huge ice blocks are pushed
downstream on the wave of water


627
00:55:32,000 --> 00:55:34,520
released by the breaking waterfall.


628
00:55:37,960 --> 00:55:39,920
This could devastate the town.


629
00:55:44,760 --> 00:55:48,320
But, this year,
the townspeople's luck is in.


630
00:55:48,320 --> 00:55:50,440
The town has escaped flooding.


631
00:55:55,080 --> 00:55:59,240
Crucially, the ice blocks did not
dam the river, it's running free.


632
00:55:59,240 --> 00:56:00,920
And the date of the break-up,


633
00:56:00,920 --> 00:56:05,040
the 6th May.
Red's got it right again.


634
00:56:06,680 --> 00:56:11,040
I don't use any of these here gauges
and mechanical assistance,


635
00:56:11,040 --> 00:56:16,080
I just go by what I see on
the river as I walk it down.


636
00:56:16,080 --> 00:56:21,120
And I say I walk it down, back and
forth every day on the river to see


637
00:56:21,120 --> 00:56:26,040
what's happening, and from that,
I gauge when it's going to hit here


638
00:56:26,040 --> 00:56:29,880
and what the situation is going
to be like when it does get here.


639
00:56:29,880 --> 00:56:31,520
You know,
when it went this morning,


640
00:56:31,520 --> 00:56:34,160
I said to my students,
"Guess what the date is?"


641
00:56:34,160 --> 00:56:36,720
Red told us it was the 6th May
and we were, you know, I'm not


642
00:56:36,720 --> 00:56:39,720
surprised, because we've been here a
couple of times and that's happened.


643
00:56:39,720 --> 00:56:42,760
Ten days, two weeks out and he just
looks around and goes "5th May."


644
00:56:42,760 --> 00:56:45,000
How does he know that?


645
00:56:45,000 --> 00:56:46,480
It's incredible.


646
00:56:46,480 --> 00:56:48,720
It's because he just has lived
on this river


647
00:56:48,720 --> 00:56:52,400
and lived this break-up
for 50 years.


648
00:56:53,640 --> 00:56:57,640
Ice scientists are improving
the accuracy of their predictions


649
00:56:57,640 --> 00:56:59,760
all the time, but in the meantime,


650
00:56:59,760 --> 00:57:02,960
the people of Hay River have a
remarkable guardian.


651
00:57:02,960 --> 00:57:07,280
Red, you were completely right this
year. Are you right every year?


652
00:57:07,280 --> 00:57:09,040
No, I'm...


653
00:57:09,040 --> 00:57:15,560
I miss the odd one.
Yes, 1985, I missed it.


654
00:57:17,800 --> 00:57:22,760
For a free Open University
illustrated poster of polar regions,


655
00:57:22,760 --> 00:57:28,320
call the number on the screen.
Or order online by going to


656
00:57:28,320 --> 00:57:35,400
bbc.co.uk/frozenplanet and follow
the links to Open University.


657
00:57:41,840 --> 00:57:45,440
Subtitles by Red Bee Media Ltd


658
00:57:45,440 --> 00:57:48,480
E-mail subtitling@bbc.co.uk