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02:12threatening to flood the world's coastlines.
02:16Penguins are walking off to their death
02:18in inexplicable suicide marches.
02:22Seals are struck blind by ultraviolet rays.
02:29Starfish are unable to reproduce.
02:32And the continent's largest land animal,
02:34a creature smaller than a common housefly,
02:37is facing possible extinction.
02:43And now, on newly exposed rocky landscapes,
02:46seeing sunlight for the very first time,
02:49green vegetation is thriving in the world's largest desert.
02:57Has an irreversible environmental change begun here?
03:00Or can we, as a global community,
03:03work together to save our planet as well as ourselves?
03:10This is the Antarctica Challenge.
03:14The world is more than a scientific potential.
03:19The world is more than a scientific potential.
03:19In part where we have become more than a temperature,
03:24the world could be more than a critical potential.
03:24The world is more than a constant growing range.
03:59According to the National Oceanic and Atmospheric Administration, global temperatures have
04:04been increasing steadily for the past 100 years, with seven of the eight warmest years
04:10on record occurring since 2001.
04:17The most dramatic rise has been here, in Antarctica, as scientists from every discipline search
04:22for clues, and hopefully answers.
04:28Warming temperatures here mean melting ice, and that means flooding for the rest of the
04:32world.
04:38Dr. Julian Scott, a geophysicist with the British Antarctic Survey, believes we have
04:44to prepare for this catastrophe today.
04:47Dr. Julian Scott, British Antarctic Survey, British Antarctic Survey
04:47Adding the water to the ocean will cause more flooding, and we'll need to put up more flood
04:54defences and build our cities in a different way because of it.
05:14Pine Island is one of Antarctica's largest glaciers.
05:18Over 250 km long, approximately the distance between New York City and Boston, and 2 km thick,
05:26it is the greatest contributor of ice flow into the ocean of any ice drainage basin in the
05:31world.
05:36In this time-lapse photography of a melting glacier, we can see just how quickly large areas of ice can
05:43move from the rocky shores to the sea.
05:50Through his extensive study, Dr. Scott has found that Pine Island Glacier alone is currently adding 46 gigatons of fresh
05:58water to the world's sea level every year.
06:03The main reason the glacier is increasing in speed at the moment is thought by most scientists working on the
06:12area to be due to warm ocean water.
06:15Now, this isn't necessarily water that's been affected by atmospheric changes in the recent history.
06:23This is deep ocean water off the edge of the continental shelf that is somehow being pushed up onto the
06:31continental shelf by the wind patterns and the pressure systems in Antarctica.
06:39And shifting warm water right to the area of this glacier where it starts to float.
06:45Now, this is thinning this area of the glacier, and by thinning this floating portion of the glacier, this causes
06:51a reduction in the pressure, which means there's less holding the glacier back, which means it can speed up.
07:02Another cause of the faster moving ice is the warming of the newly exposed rock that extends beneath the ice.
07:09As the sun warms this bare rock, it creates an endothermic reaction that heats the rock bed and melts the
07:16ice from underneath.
07:21Antarctica holds 70% of the world's fresh water in its ice.
07:30According to NASA, if the land ice of the west coast of the continent alone were to melt, the world's
07:36sea level would rise 18 to 20 feet.
07:40This would result in massive flooding around the world, as well as increased weight and pressure on the world's seabed.
07:47This, in turn, could provide severe stress on oceanic fault lines, resulting in earthquakes and tsunamis.
08:02Even the ozone hole may be contributing to this problem by the way it has changed weather patterns here.
08:08Now, one theory that's been suggested is it actually could be anthropogenic, but due to the ozone hole over Antarctica,
08:16which has been shown to change the weather systems around Antarctica.
08:20Or we could be seeing El Niño type effects in the southern weather systems, that the wind is driving this
08:28ocean water up to the front of the glacier.
08:34There's a huge ice sheet grounded largely below sea level, which is why we are concerned about it, but the
08:43ice is very thick and extends way above sea level.
08:46So, obviously, if we were to lose it, it would contribute to the global sea levels.
08:51And, in fact, the whole of the West Antarctic ice sheet could contribute up to five meters.
08:57And the Amundsen Sea area, where Pine Island and Thwaites glaciers are, that have both been noted to be speeding
09:03up recently,
09:05that could contribute around one and a half meters to global sea level.
09:12Dr. Scott is one of many scientists dedicated to studying Antarctica.
09:25He spends long periods of study in the field, but returns home to analyze his findings.
09:34His headquarters are located here, half a world away, in the historic university town of Cambridge, England.
09:43His research, along with others at the British Antarctic Survey, pays tribute to the first scientific expeditions in Antarctica 100
09:52years ago.
09:57While many ships and lives were lost in those early days by explorers the world over,
10:03it was one British explorer who was perhaps best known for paving the way for scientific study here today,
10:10Sir Ernest Shackleton.
10:13In 1909, he led one of the very first scientific expeditions to Antarctica.
10:19Ernest Shackleton really filled the old dictionary definition of an explorer,
10:25one who explores to discover new lands.
10:28There are very few new lands left to discover, under the sea possibly, and of course in space in the
10:33future.
10:34But for scientists, there are always new lands, and they never stop discovering.
10:39Well, during the early expeditions, polar science was really a matter of observation, more than very precise science.
10:45I mean, they didn't have the gear.
10:47But a lot of scientific research was accomplished during the New World Expedition,
10:51and they did accomplish some notable firsts.
10:53They did discover the South Magnetic Pole, which is not a fixed point, but moves about, about six miles a
11:00year.
11:06That was enough for Shackleton to secure a second expedition.
11:13However, this time, it didn't turn out as expected.
11:16When the ship became trapped in the ice, there was hope that she would rise above it and be able
11:21to be floated once more.
11:23But instead, she was slowly crushed.
11:25They watched with horror as this took place.
11:29Eventually, the mast came down, and you see the group, rather desolate on the ice.
11:36They're home, because the ship is always a sailor's home, gone.
11:39They were in a very dangerous situation.
11:41No one knew where they were.
11:55Shackleton and his crew were left stranded and fighting for their lives for over a year and a half.
12:02Amazingly, Shackleton led his endurance crew back to safety without losing one life.
12:10Their incredible story of survival is commemorated by one of Antarctica's very few museums.
12:18With many of their supplies still on its shelves, this unique museum provides an eerie reminder
12:24of how difficult survival is in this harsh land.
12:31A struggle which helped give inspiration to an international treaty 50 years later.
12:55For the first time in human history, 12 nations were able to agree to administer an entire continent.
13:02Signed on December 1, 1959, the Antarctica Treaty bans any military activity and restricts any human occupation solely to scientific
13:12study.
13:14Never before has the world come together to jointly govern a continent, rather than fight over its ownership.
13:21Today, there are 47 nations ensuring the peaceful use of Antarctica, strictly for scientific research.
13:29One of the more recent countries to sign the treaty is Ukraine.
13:37Dr. Eugenie Keryagan is a seismologist from Ukraine.
13:41His country joined the treaty in 1992 and took over Great Britain's Faraday Research Station, renaming it Vernadsky Station.
13:52He believes that the melting fresh water is contributing to the further melting of the ice in a very unusual
13:58way.
14:00Dr. Eugenie Keryagan is a problem.
14:02Dr. Eugenie Keryagan is a system ofamiętств and will appear in the region of the Arctic.
14:05Dr. Eugenia Keryagan is a system of the alcanzation to run over the coast of the Arctic.
14:23Dr. Eugenia Keryagan is a system of an extraordinary 세상 of wild water.
14:26Dr. Eugenia Keryagan Sobano, the areas of L enthusiasts of the Arctic and the compost a lot of the sun
14:28will lift up.
14:28to increase the mass of the water, which will disappear in the atmosphere.
14:35This, in my opinion, can lead to more percent of the fall of rain and snow.
14:43In this year, in December of this year, the level of snow had its maximum value,
14:52about 1,8 meters.
14:56These rains were more than in winter.
15:01In the summer, the rain was more than in winter.
15:10Dr. Kiryagin warns that the increased precipitation will accelerate the melting of the glacier ice,
15:17compounding and accelerating the process as more fresh water from the melting land ice
15:22dilutes the salt water of the Antarctic Ocean.
15:26Since fresh water evaporates faster than salt water, there will be a lot more rain and snow here.
15:35Over the past 20 years, the continent of Antarctica has diminished in size dramatically,
15:40shrinking the ice fields at an alarming rate.
15:45How much further can Antarctica shrink before its melting ice floods the world?
15:50Dr. Kiryagin is measuring this melting every day through a series of seismology tests,
15:55designed to record shifts in glacial movement.
15:58This, on the station, I do a seismic study study.
16:05One of the interesting elements of my work is studying the current
16:13activity on the continent, around the station, in the equator.
16:20Two years ago, I started to count the number of signals that are generated from the nearest
16:28lake on the continental part.
16:36Dr. Keryagan has been recording vibrations from nearby glaciers.
16:41He claims that the increased frequency of seismic signals tells them that the climate is warming.
16:48I can say that in a day, I registered about 1000 signals.
16:55These are signals from the burning of the ice surface.
17:00That the climate is visible, the climate is visible.
17:05There is an increase in the average temperature.
17:09And, probably, this process is causing the increase in the number of signals.
17:16On my opinion, the increase in the number of signals,
17:18which are generated by the nearby glaciers,
17:21indicates that the increase in the temperature in Antarctica.
17:39If he's right, more glaciers will soon resemble this one,
17:43diluting the sea with fresh ice water at unprecedented speeds.
17:47At this continued rate, it could mean catastrophic flooding for most of the coastal towns and cities of the planet.
18:00Are we too late?
18:01Is there anything we can do now to slow and perhaps even reverse this continent's warming to prevent world flooding?
18:09Most scientists predict that the world's coastal towns and cities will be hit the hardest by the rising sea levels
18:16and the ensuing hurricanes, earthquakes and tsunamis.
18:21Coastal cities that are the center of life to millions are at peril.
18:25Cities like San Francisco.
18:28This picturesque coastal city in California is the occasional home of renowned environmentalist and penguin specialist,
18:34Dr. David Ainley, who, after spending more than 30 years in the field in Antarctica,
18:40has likely spent more time there than here.
18:43His contribution to scientific study in Antarctica is so significant,
18:47a mountain there has been named after him, Ainley's Peak.
18:55He believes that cities like his will soon have some serious environmental issues to deal with.
19:00I think we are going to see some major problems.
19:04We are too late by 20 years.
19:09And, I mean, it's really serious.
19:13Well, anybody that lives on the coast is going to be having problems.
19:17It doesn't take much of a rise in sea level, just an inch.
19:20And that's huge when you get a storm surge, you know, from a nor'easter or hurricane or that sort
19:27of thing.
19:28You know, foreclosures are happening on beachfront.
19:31And that's probably a good thing because those properties are history anyway.
19:45And while today's Antarctic scientists are suggesting we need to relocate to higher ground,
19:51the penguins here are already being forced to do the same thing.
19:57There are up to seven species of penguins that might occur in the Antarctic.
20:01Four of those are relatively common.
20:03And if we start from the largest, the emperor penguin,
20:06it's the one that is least tolerant to temperature changes.
20:09It's the one that nests the further south, the one that nests in the coldest climates.
20:13Next would be the Adelie penguin.
20:14They're very much dependent on ice flows and the near ice conditions for hunting.
20:19So they again would be very much affected by rising temperature changes.
20:23The chin strap penguin is somewhere in between.
20:25It is more adaptive.
20:26It will move further north and further south than some of the other ones.
20:32But the one behind me, the gentoo, is probably the most adaptive.
20:35It's the one that might be the super penguin of the Antarctic eventually.
20:50As well, warming waters are responsible for a drastic decline in the penguin's sole food source, the krill.
21:10Krill are small shrimp like marine crustaceans.
21:13They're the primary food supply of penguins and all other Antarctic animal life.
21:19They travel in schools of millions and are very sensitive to water temperature.
21:24A rise in temperature of even half a degree hinders their ability to reproduce,
21:30seriously impacting the penguins here.
21:33Compounding this problem is that more whales are entering these waters now that they have become warmer.
21:39In one gulp, these whales can consume a quantity of krill that would otherwise feed 2,000 penguins.
21:46If the krill move out of the area entirely, these penguins have to find another food source,
21:51and most of them won't be able to.
21:52When krill's available, all of the species of smaller penguins,
21:56here are the adeli, the chin strap, and the gentoo, will eat them almost exclusively.
22:00It's only when the krill is in diminishing numbers that they will return to other species.
22:06Well, if there's no food, there's no birds, pretty simply.
22:09As the food resources change, it's only the species that are able to adapt that are going to survive.
22:15The other species, such as the adeli, the emperor, will have to either stay south or move south into the
22:20colder waters
22:20and try to catch the krill that are still there.
22:48Over the past 25 years, the population of the adeli penguins here in the Antarctic Sea
22:52peninsula has dropped by 50%, while the chin strap numbers have fallen by as much as 65%.
22:59But the most noticeable relocation recently has been among the gentoos.
23:08The biggest change that's occurred here is the movement of the gentoo.
23:11They're moving further south, they're moving south in greater numbers,
23:14they're moving higher up onto the slopes.
23:15When you have small numbers of them, they will nest in the near shore areas.
23:19As the population increases in a preferred nesting locale, they'll move upslope.
23:23So we have penguins behind me, we have penguins on a higher slope to the right,
23:27and then sometimes we'll get penguins even higher up on the slope behind.
23:39So while it looks as though the gentoo is poised to take over the warming west coast of Antarctica,
23:44the retreating penguin species are moving to the colder climates down the coast,
23:49and individual penguins have begun wandering off to certain death,
23:54a phenomenon only recently observed in the past five years.
23:59Viewed by many as suicide marches, lone penguins have been observed to leave their colony,
24:04walk away from the sea, and venture deep into the continent, never to return.
24:11Penguin scientist Dr. David Ainley has been studying penguin behaviour for 40 years,
24:16most of those years in the field in Antarctica.
24:19His theory is that these so-called suicidal penguins are actually pioneers.
24:24A kind of noble explorer who ventures out on his own to find a new home for his colony.
24:30We have these individual penguins that purportedly are committing suicide by walking away from the sea
24:42into the interior of the Antarctic, kind of like Scott did.
24:47When these populations expand, it's because of pioneers that find new places.
24:55They go off and disappear and nobody hears about them anymore, unless they have a good publicist.
25:09This unusual behaviour was first noted when an iceberg measuring 97 nautical miles
25:14came to rest at the shore of a large penguin colony, effectively blocking access to their food supply.
25:22And so this big iceberg, B-15A, parked itself in the southern Ross Sea.
25:30And so there was a lot of disoriented penguins during those five years
25:34that essentially have this 97-mile-long fence that went across the Ross Sea.
25:39So during those five years, there was an increase in the numbers of these penguins
25:45that were really beside themselves about which way to go
25:48and which would get them to where they wanted to go.
25:51Several more of these penguins that were going the wrong way, so to speak.
25:56These would be the heroes that penguins would write about.
26:08However, without the warming temperatures that placed giant icebergs in their path,
26:13there would be no heroic penguins looking for a new home for their tribe.
26:18Suicide missions aside, the relocation of penguin populations
26:22is taking a significant toll on their numbers.
26:28As well, global warming in the ozone hole have combined to threaten penguin populations
26:34across the continent and may very well cause their extinction.
26:54For many penguin species, warming temperatures have reduced the size of ice flows
26:59upon which species such as the emperor penguin hatch their young.
27:04Combined with the increased winds resulting from the ozone hole,
27:08the entire colonies of baby chicks are being blown off the ice to certain death.
27:15But as is being shown at Point Geology, that colony has decreased by 50% since the mid-70s.
27:26And partially it is related to the fact that the fast ice has become too thin,
27:34and so it gets blown out repeatedly and many eggs and chicks are blown away on the ice,
27:41you know, with parents sitting on them.
27:42It's okay with the parents, you know, they're used to water,
27:45so this is happening with greater frequency.
28:11Also occurring with greater frequency is an extended period of dependency by young penguins
28:19such as this one have usually begun to collect food for themselves by now,
28:24yet more and more of these penguins have been observed to be relying on their parents.
28:28Penguins far beyond the age of nestling are having trouble leaving the nest as it were,
28:33perhaps afraid to face the relatively bleak prospects of their diminishing food supplies.
28:49Failed mating attempts such as this one have been observed more and more in the past five years,
28:54suggesting the birds are becoming more disoriented,
28:57perhaps another result of their difficulty in adapting to the rapidly changing environment.
29:20Another cause for concern, especially among the younger penguins,
29:24is the increase in attacks from a predatory bird known as the scua.
29:34Usually these birds only attack the eggs of penguins,
29:38but as the number of eggs has been reduced,
29:40the scua has now become a predator of baby chicks.
29:53And since these birds prefer a warmer climate and a rocky shore to live on,
29:57more of them are entering the peninsula area,
29:59providing the remaining penguin populations something they are not used to, a predator.
30:14While the warmer climate in Antarctica is impacting on the survival of the once plentiful penguin populations,
30:22the increased temperatures are also resulting in the decline of Antarctica's only indigenous land animal,
30:28the common fly.
30:32Okay, what we've been looking at here are little tiny terrestrial invertebrates
30:37that are the main animal fauna on the Antarctic Peninsula.
30:41But they're virtually the only fauna you see in the Antarctic.
30:45And what I've been looking at specifically here is a little fly.
30:48There are only two real flies in Antarctica, and this is one of them.
30:53It's the largest land animal in Antarctica.
30:57And if you're lucky, it's about four or five millimeters long and about half a milligram in weight.
31:02So it's a really rather small, cute little insect, basically.
31:08It's a fly without any wings.
31:10The Antarctic Peninsula, it's one of the three fastest warming parts of the planet at the moment.
31:15And these little invertebrates in their distribution are potentially sensitive to these changes.
31:21So if it gets warmer, as it is doing, they can carry out their life cycle quicker.
31:28What this means is they die faster.
31:35The warmer habitat here can be deadly.
31:39The barren rock now being exposed by melting ice is very dry, depriving the creatures of water.
31:47It doesn't have very good water holding capacity.
31:50If you warm it up, and particularly if you have increased amounts of sunshine, direct sunshine landing on it,
31:55it actually dries out more quickly.
31:57So you actually may end up with a warmer habitat, but one in which there's no water available.
32:02Now that combination of effects is actually then negative on these little invertebrates.
32:11And while warming temperatures are creating deadly environments for Antarctica's land animals,
32:17the warmer waters are having the same effect for Antarctica's marine life.
32:22And while warming temperatures are having the same effect for Antarctica's land animals,
32:35Laura Grange is a marine biologist working with the British Antarctic Survey at the Rothera research station.
32:42She tells us that an anticipated increase of only two degrees in water temperature will cause starfish and other marine
32:48life to stop reproducing.
32:50This is a starfish.
32:54All these animals are actually collected from the shallow water around the Rothera research station,
32:59and they're all collected by scuba diving.
33:02And it's also incredibly colourful, which is easily shown on this starfish.
33:06We collect them directly from outside, and then we bring them in to carry out various experiments on them.
33:12I'm actually looking at their breeding success from year to year.
33:16They're also very important because they're very sensitive to temperature change.
33:21Many scientists have actually predicted that there will possibly be a global temperature change of two degrees within the next
33:26100 years.
33:29Well, these animals in particular are very susceptible or very sensitive to changes in temperature.
33:34And therefore, because of this predicted change, both regionally but also globally,
33:38it's very unlikely that they won't be affected.
33:41And in my case, for my work, if they're not able to breed, obviously they won't be able to survive.
34:08And while global warming in Antarctica seems to be a significant threat to its fauna,
34:13the flora seems to be experiencing a genesis in what is commonly referred to as the world's largest desert.
34:26Daniela Rubling, a sub-Antarctic botany researcher, describes a new vegetation here that she has not seen before.
34:35It looks to be a combination of moss-type plant as well as potentially some algae as well,
34:42but basically chlorophyllic species that do use photosynthesis in order to produce their food and produce to grow and to
34:50survive.
34:52And it's very interesting to see it in this type of area because most of the time these islands are
34:59covered by snow,
35:01they're covered by ice, they don't see light.
35:03And so to see greenery in an area that has always been considered to be a desert,
35:08it's very interesting and exciting to see new life growing in places where it's never been previously.
35:17But perhaps the biggest mystery of the greening of Antarctica is where this new life came from.
35:24Was it always here, lying dormant in the rocky soil, or was it brought here by birds or winds?
35:32Well, I mean, the seeds or the spores of these plants may have been carried in by winds,
35:38and this may have been occurring for hundreds of years, but because it's been covered in snow,
35:43these plants have not been able to establish themselves.
35:46Whereas now, once you get exposure of rock, you get soil deposition,
35:51allowing these seeds or spores to establish themselves and grow in areas where they would never have been before.
36:01And does it stop there?
36:04Is this possibly the beginning of an entirely new ecosystem?
36:11This type of vegetation, it can serve as both food supply for animals that need to convert the plant material
36:19into energy for themselves,
36:21but also in and amongst, you can see that it could also provide shelter or protection from it for animals
36:26as well,
36:27or for smaller invertebrates.
36:28I mean, the possibilities are for more life to grow and for more species to find their way here and
36:36establish themselves as well.
36:44But in order to predict how severe climate change will affect this continent, and by extension the rest of the
36:50world,
36:50a series of measurements and data recordings is done on a daily basis by devoted scientists the world over in
36:57what is often a thankless yet essential job.
37:03Recording temperatures from the past and projecting a tendency to continue is not a very reliable method of forecast,
37:10given the wildly changing atmospheric and meteorological conditions here.
37:14I will wait a minute to see what there is and a little bit later.
37:28I do not know what was different last night when you get ahead.
37:45One of the more accurate methods involves ice core sampling.
38:02Where I'm sitting the ice is 950 metres thick. If I drill through all the way to the bedrock I
38:08will have recovered ice spanning the last 40,000 years.
38:11This is quite an important period. 40,000 years ago the earth was in an ice age, today we're in
38:17a warm period.
38:18By analysing the record of the climate from the bottom of the core to the top I will be able
38:23to see how we move from a cold period into a warm period
38:26and this helps us understand how we expect the climate to change over the next 100 years.
38:41That's a nice piece of core, about 2 metres long and round about here is 500 metres depth from the
38:47surface.
38:48That's ice that fell as snow about 5,800 years ago.
38:55Many things in the atmosphere change from summer to winter
38:58and we can see this in the ice cores when we analyse them.
39:01So when we plot out our results we see a series of waves going down the ice
39:05and these are summer, winter, summer, winter.
39:08So we can simply count the layers just like counting tree rings.
39:23Once we get the 2 metre ice core back to the surface then we pack it into insulated boxes
39:28and then it's shipped by small aircraft back to one of our coastal stations, Halley Bay,
39:33where it's loaded onto one of our ships and it's shipped back to Europe in a refrigerated container.
39:48Once it gets back to Europe we cut it into much smaller pieces and send each of these pieces out
39:53to different laboratories for different analyses
39:55to try to understand all the things that are happening in the climate and the atmosphere.
40:03This study has shown that the increase of greenhouse gases found in the air bubbles is directly proportionate to the
40:09increase in size of the ozone hole.
40:27And what if the hole gets bigger?
40:30How many lives might be at risk as a result of the cancer inducing UV rays?
40:42One of the most important areas of study in Antarctica today is the ozone hole.
40:47As its regularly increasing size approaches human habitats such as New Zealand,
40:52the related increase in cases of skin cancer has made ozone study a high priority.
41:12At Vernadsky Station, ozone scientist Igor Gavatsky keeps a daily vigil of recording ozone readings every three hours.
41:27To do this he uses a Dobson ozone spectrophotometer, an instrument used by the British Antarctic Survey to study the
41:34ozone hole.
41:39The hole was discovered in 1985 by Dr. Jonathan Shanklin using this very device.
41:45Well this sort of white box that we've got in front of us is the Dobson ozone spectrophotometer.
41:51And as you might guess from the fact that you've got ozone in its name, it's for measuring ozone in
41:56the atmosphere above us.
41:58And we can see on the top of the instrument this black tube with a prism at the top.
42:04And that allows us to direct a beam of sunlight into the instrument.
42:08Now this sunlight has come through the Earth's atmosphere through the ozone layer
42:13and it slightly changed that beam, particularly in the ultraviolet part of the spectrum.
42:17And what we do inside the instrument is select out those wavelengths or parts of the ultraviolet spectrum
42:23that have been affected by the ozone.
42:25And by looking at the ratio of intensity of two wavelengths,
42:29we can work out how much ozone was in the path from the instrument to the sun.
42:34And the observer would make some adjustments on the levers and the dial to either select the wavelength
42:42or to find out what the absorption was.
42:46So it's essentially a very simple design, designed by an Oxford professor of physics in the 1920s
42:54and it's still the world standard for measuring ozone from the ground.
43:04Measurements recorded here on Gallandes Island detail the amount of ozone in the atmosphere.
43:10Recent measurements have ranged from 270 to 300 Dobsons.
43:15And this is good news.
43:16A measurement of 260 or less is dangerous for people and animals.
43:27This allows all wavelengths of ultraviolet rays through, burning unprotected skin in five minutes
43:33and blinding Antarctica's land animals.
43:38This Waddell seal, for example, has been blinded by UV rays and this is becoming an increasing problem.
43:44There seems to be evidence that the changes in the ozone hole are having an effect on climate change here
43:49as well.
43:51The changes in the ozone hole certainly have been driving some of the changes that we've seen in surface climate.
44:01I think that's now pretty well established that one of the big changes in Antarctic climate over the last 30
44:08years or so
44:09has been that the westerly winds that blow around the continent have speeded up maybe 20%.
44:16And we now think that a large part of that is due to the reduction of ozone in the stratosphere.
44:33Since its discovery in 1985 by Dr. Jonathan Shanklin, the hole has been getting bigger every week.
44:40Now that it has reached an area in excess of 25 million square kilometers, the size of North America,
44:47it has, for the very first time, stopped growing.
44:51This year's ozone hole has actually been quite unusual.
44:56Quite often it's not a circular thing, it can be quite elliptical,
44:59and sometimes when it's elliptical it sweeps northwards over the tip of South America,
45:04the Falkland Islands and South Georgia.
45:06And that can usually happen once every few weeks.
45:09This year it's only happened once.
45:11The hole has remained very, very circular and consequently very stable.
45:17The reason for this, many scientists believe, has been the Montreal Protocol,
45:22an urgently created global initiative to ban the use of gases that destroy ozone,
45:27such as chlorofluorocarbons or CFCs.
45:31The treaty was signed on September 16, 1987, by almost all the nations of the world,
45:36and the results have made a difference.
45:39Timor-Leste, San Marino and Andorra are the three that haven't signed up.
45:45Everybody else has signed up to the basic protocol, and it's working.
45:49It's really quite amazing.
45:50The amount of these ozone-destroying substances in the atmosphere is clearly dropping.
45:56It will take a few years before what we see at the surface filters through
46:00to the high atmosphere above Antarctica.
46:03But nevertheless, I think even in Antarctica,
46:05we're starting to see the amount of ozone-destroying substances go down.
46:10But it's a slow process because they're very stable,
46:12and it's probably going to be another decade before we can be certain
46:18that things are actually improving.
46:20But we can confidently say that we're on the right track.
46:25And while Dr. Shanklin believes the reduction of our use of CFCs
46:29is the reason why the ozone hole has stopped growing,
46:33his counterpart in Antarctica,
46:35Igor Vodovsky, has recorded measurements that suggest that the hole is actually shrinking.
47:05The correlation between the worldwide CFC band and the reversal of the ozone hole size
47:10is the same.
47:10The correlation between the areas will hopefully encourage further collective efforts
47:13to help reduce the damage to ourselves and our planet.
47:18The Montreal Protocol, together with the signing of the Antarctica Treaty,
47:22have proven to be two unprecedented international cooperatives
47:26that ended up protecting the Earth's environment.
47:28No territorial disputes, no military presence, no natural resource mining,
47:35no commercial interests, no residential land claims.
47:40Antarctica is unique in so many ways.
47:43It is the driest, windiest, highest and coldest continent on Earth.
47:50We can now add to that list that it is the only place on Earth
47:54where the world has come together in peace
47:56to effect environmental change for the betterment of all life.
48:11No matter how insurmountable the environmental crisis may seem to be,
48:15we have proven that with an internationally united effort,
48:18we can answer the call to any challenge.
48:23Even the Antarctica challenge.
48:30...
48:34...
48:35...
48:41...
48:42...
48:43...
48:45...
51:07Okay, we'll see you in a bit.
51:15There we go.
51:43So there you have it, swimming.
51:44Antarctica's newest sport.