1 00:00:22,320 --> 00:00:24,160 Looking down on our planet, 2 00:00:24,280 --> 00:00:25,800 it may come as a surprise 3 00:00:25,920 --> 00:00:29,640 to find just how much of it is blanketed in snow and ice. 4 00:00:29,760 --> 00:00:32,680 These vast frozen wildernesses 5 00:00:32,800 --> 00:00:35,920 cover more than a fifth of the earth... 6 00:00:37,360 --> 00:00:40,000 Yet some areas are so remote and inhospitable 7 00:00:40,120 --> 00:00:41,520 that, even today, 8 00:00:41,640 --> 00:00:43,680 the closest we've come to exploring them 9 00:00:43,800 --> 00:00:45,520 is from space. 10 00:00:49,640 --> 00:00:51,200 More than a decade ago, 11 00:00:51,320 --> 00:00:53,440 the first series of frozen planet 12 00:00:53,560 --> 00:00:57,160 examined life in the arctic and the antarctic. 13 00:00:58,840 --> 00:01:01,280 In this series, we will explore 14 00:01:01,400 --> 00:01:04,440 all of earth's frozen habitats... 15 00:01:06,240 --> 00:01:08,680 From its highest peaks, 16 00:01:08,800 --> 00:01:10,920 to its snowbound deserts... 17 00:01:14,280 --> 00:01:16,240 To deep beneath the ice. 18 00:01:19,640 --> 00:01:21,160 Between them, they contain 19 00:01:21,280 --> 00:01:24,520 an astonishing array of animals... 20 00:01:26,760 --> 00:01:30,560 Many that are found nowhere else on earth. 21 00:01:38,960 --> 00:01:41,640 We will watch the extraordinary ways 22 00:01:41,760 --> 00:01:44,880 by which they manage to survive. 23 00:02:00,400 --> 00:02:01,960 Using new technology, 24 00:02:02,080 --> 00:02:04,320 such as racer drones, 25 00:02:04,440 --> 00:02:07,880 we'll gain a new insight into their remarkable lives. 26 00:02:10,280 --> 00:02:13,840 But just as we're beginning to understand its wildlife, 27 00:02:13,960 --> 00:02:16,720 we are recognising an alarming truth. 28 00:02:16,840 --> 00:02:19,960 Our frozen wildernesses are disappearing 29 00:02:20,080 --> 00:02:23,360 at faster rates than ever before. 30 00:02:27,960 --> 00:02:30,240 And never has it been more important 31 00:02:30,360 --> 00:02:35,560 to understand what is going on in these icy territories. 32 00:02:44,360 --> 00:02:46,120 In this first episode, 33 00:02:46,240 --> 00:02:49,360 we will travel from pole to pole... 34 00:02:50,840 --> 00:02:53,080 To celebrate the precious wildlife 35 00:02:53,200 --> 00:02:57,120 foundin our frozen wildernesses... 36 00:03:01,400 --> 00:03:03,920 And witness their wonders... 37 00:03:05,200 --> 00:03:07,920 While there is still time to save them. 38 00:03:09,760 --> 00:03:12,720 This is frozen planet ii. 39 00:03:49,240 --> 00:03:53,000 We begin our journey in the far south of the planet. 40 00:03:55,080 --> 00:03:56,880 After six months of darkness, 41 00:03:57,000 --> 00:03:59,160 the sun is starting to return 42 00:03:59,280 --> 00:04:02,800 to the largest frozen expanse on earth. 43 00:04:04,240 --> 00:04:05,560 Antarctica. 44 00:04:06,880 --> 00:04:10,320 A continent almost twice the size of Australia. 45 00:04:26,520 --> 00:04:30,640 Here, temperatures fall to minus 80 degrees centigrade. 46 00:04:32,040 --> 00:04:34,680 It's the coldest place on earth. 47 00:04:41,640 --> 00:04:43,360 There is only one animal here 48 00:04:43,480 --> 00:04:47,280 Hardy enough to raise its family in winter. 49 00:04:50,880 --> 00:04:52,680 The emperor penguin. 50 00:04:55,400 --> 00:04:59,560 Winds here can reach speeds of over 100mph, 51 00:04:59,680 --> 00:05:03,600 and a chick is in real danger of freezing to death. 52 00:05:10,320 --> 00:05:16,040 But his parents are possibly the most devoted in all nature. 53 00:05:16,160 --> 00:05:17,680 They shield him 54 00:05:17,800 --> 00:05:20,320 from the full force of the icy blast... 55 00:05:21,920 --> 00:05:25,520 And huddle together to create a tight creche. 56 00:05:26,760 --> 00:05:29,440 Within it, the chicks, remarkably, 57 00:05:29,560 --> 00:05:31,560 can maintain their body temperature 58 00:05:31,680 --> 00:05:33,960 of 37 degrees celsius... 59 00:05:40,640 --> 00:05:43,560 Until one spring day, 60 00:05:43,680 --> 00:05:47,080 when the chicks have grown to almost a metre tall... 61 00:05:50,800 --> 00:05:55,080 The parents simply walk away. 62 00:06:04,360 --> 00:06:07,520 Their parental duties are complete... 63 00:06:11,040 --> 00:06:14,880 And they will never again return to their chicks. 64 00:06:24,080 --> 00:06:27,600 As the days pass, the chicks grow hungry. 65 00:06:36,040 --> 00:06:39,920 And their only chance of finding a meal is out at sea. 66 00:06:41,880 --> 00:06:46,400 But that could be 30 miles away across the frozen ocean. 67 00:06:54,080 --> 00:06:57,480 When one makes the first bold move... 68 00:07:01,400 --> 00:07:03,400 The rest follow. 69 00:07:09,160 --> 00:07:11,520 They set off at a steady pace. 70 00:07:14,800 --> 00:07:19,360 But sliding on your belly is an easy option. 71 00:07:24,240 --> 00:07:28,040 Out on this ever-changing platform of the frozen sea... 72 00:07:29,200 --> 00:07:32,480 Towering walls of ice stand in their way. 73 00:07:38,120 --> 00:07:41,520 This will require mountaineering skills. 74 00:07:43,240 --> 00:07:47,560 Beaks come in useful as ice picks. 75 00:07:56,640 --> 00:08:00,640 And tobogganing is a quick way down. 76 00:08:19,520 --> 00:08:24,080 As they near the sea, the ice becomes more unstable. 77 00:08:27,680 --> 00:08:32,000 Even the smallest crack is met with suspicion. 78 00:08:37,440 --> 00:08:39,560 And with good reason. 79 00:08:41,120 --> 00:08:45,000 A crack can quickly turn into a gaping chasm. 80 00:08:59,240 --> 00:09:01,240 If they can't escape, 81 00:09:01,360 --> 00:09:03,760 the panicked chicks will be doomed. 82 00:09:23,640 --> 00:09:25,320 Made it. 83 00:09:30,840 --> 00:09:34,440 Finally, the end is in sight. 84 00:09:37,000 --> 00:09:39,000 The southern ocean. 85 00:09:44,320 --> 00:09:47,440 In some years, the sea ice is so unstable 86 00:09:47,560 --> 00:09:50,520 that none make it as far as this. 87 00:09:56,800 --> 00:10:00,400 These chicks are the lucky ones. 88 00:10:11,680 --> 00:10:13,800 Not the most graceful entry. 89 00:10:28,200 --> 00:10:30,960 But they are in their element. 90 00:10:32,040 --> 00:10:33,400 The sea. 91 00:10:39,360 --> 00:10:42,560 They may have endured the toughest of upbringings, 92 00:10:42,680 --> 00:10:45,960 but now they can reap the benefits 93 00:10:46,080 --> 00:10:48,280 of the long summer ahead, 94 00:10:48,400 --> 00:10:51,800 and feed in the richest waters on earth. 95 00:11:17,120 --> 00:11:18,480 In winter, 96 00:11:18,600 --> 00:11:22,240 the seas around Antarctica are so cold that they form 97 00:11:22,360 --> 00:11:25,520 a platform of ice twice the size of Europe. 98 00:11:29,160 --> 00:11:31,080 But in summer, 99 00:11:31,200 --> 00:11:34,480 just off the shores of the antarctic peninsula, 100 00:11:34,600 --> 00:11:38,960 the ice cover breaks up into millions of tiny ice roes. 101 00:11:42,640 --> 00:11:45,600 It's an excellent place for a weddell seal 102 00:11:45,720 --> 00:11:48,120 to rest up after a night's feed. 103 00:11:56,920 --> 00:11:59,200 The bay is sheltered... 104 00:12:01,160 --> 00:12:04,040 And the water calm. 105 00:12:13,800 --> 00:12:16,360 But there are great dangers here. 106 00:12:49,680 --> 00:12:51,480 Killer whales. 107 00:12:52,560 --> 00:12:57,200 This pair of 15-year-olds are learning what is perhaps 108 00:12:57,320 --> 00:13:00,360 the most complex hunting technique in nature. 109 00:13:02,960 --> 00:13:05,000 After sizing up their prey... 110 00:13:07,720 --> 00:13:11,000 They assemble 30 metres away... 111 00:13:16,360 --> 00:13:18,840 And then launch an attack. 112 00:13:21,400 --> 00:13:22,680 They swim in tandem, 113 00:13:22,800 --> 00:13:25,160 synchronising their tail beats... 114 00:13:27,480 --> 00:13:29,200 To create a wave. 115 00:13:34,280 --> 00:13:36,520 The seal is washed off... 116 00:13:39,680 --> 00:13:42,240 But it won't give up without a fight. 117 00:14:08,040 --> 00:14:09,920 The seal has escaped... 118 00:14:11,920 --> 00:14:13,920 This time. 119 00:14:16,920 --> 00:14:19,520 But for the young killer whales, 120 00:14:19,640 --> 00:14:21,880 help is at hand. 121 00:14:24,680 --> 00:14:28,280 They live in multi-generational family groups... 122 00:14:30,200 --> 00:14:34,720 Led by an experienced female who can be over 100 years old. 123 00:14:38,440 --> 00:14:40,840 Helped by her accumulated knowledge, 124 00:14:40,960 --> 00:14:44,000 the whales have become ruthlessly efficient. 125 00:15:02,640 --> 00:15:06,080 They have a 90% hunting success rate... 126 00:15:10,200 --> 00:15:15,680 But a killer whale needs to eat a seal a day... 127 00:15:17,640 --> 00:15:22,200 So this 14-strong family has a lot of hunting to do. 128 00:15:26,960 --> 00:15:28,320 Spreading out, 129 00:15:28,440 --> 00:15:33,160 they spy-hop to search the ice roes. 130 00:15:38,920 --> 00:15:41,120 When a seal is spotted, 131 00:15:41,240 --> 00:15:45,440 the scouts alert the family with a rallying call. 132 00:15:54,520 --> 00:15:56,000 But if they are to catch a seal 133 00:15:56,120 --> 00:15:58,560 resting on such a large piece of ice... 134 00:16:00,080 --> 00:16:03,280 The hunters need to change their tactics. 135 00:16:08,240 --> 00:16:12,440 This time, they produce a sub-surface wave. 136 00:16:17,640 --> 00:16:20,040 It breaks the ice into smaller pieces. 137 00:16:24,360 --> 00:16:27,560 But the seal still has a raft... 138 00:16:30,000 --> 00:16:34,080 And appears to be protected from any oncoming wave. 139 00:16:37,480 --> 00:16:41,640 The matriarch whale, however, has a plan. 140 00:16:45,960 --> 00:16:48,240 Working in a coordinated way, 141 00:16:48,360 --> 00:16:51,760 the pod push the seal's ice platform 142 00:16:51,880 --> 00:16:53,680 into clearer water. 143 00:17:16,800 --> 00:17:20,480 The matriarch now tries another tactic 144 00:17:20,600 --> 00:17:23,040 which will avoid injury. 145 00:17:26,280 --> 00:17:28,040 Blowing bubbles. 146 00:17:33,360 --> 00:17:36,760 They disorientate the tiring seal... 147 00:17:43,360 --> 00:17:48,080 And the whales move in for the kill. 148 00:17:59,720 --> 00:18:02,880 Only about 100 killer whales in the world 149 00:18:03,000 --> 00:18:05,000 hunt using this technique. 150 00:18:09,680 --> 00:18:13,760 It's an ingenious solution to the problem of finding prey, 151 00:18:13,880 --> 00:18:17,680 here in the most extreme frozen habitat on earth. 152 00:18:27,440 --> 00:18:29,840 Antarctica is so cold 153 00:18:29,960 --> 00:18:33,320 because of its position at the far south of the planet. 154 00:18:35,600 --> 00:18:37,320 But travel north... 155 00:18:37,440 --> 00:18:39,760 And you'll find other icy worlds 156 00:18:39,880 --> 00:18:43,600 that are created by altitude, in the mountains. 157 00:18:45,880 --> 00:18:47,920 The andes in South America, 158 00:18:48,040 --> 00:18:52,200 with its 4,500 miles of snow-covered peaks, 159 00:18:52,320 --> 00:18:55,160 is the longest range on earth. 160 00:18:59,800 --> 00:19:04,280 These high icy worlds even exist close to the equator, 161 00:19:04,400 --> 00:19:06,960 where the sun is at its hottest, 162 00:19:07,080 --> 00:19:09,600 as on mount Kenya in Africa. 163 00:19:15,760 --> 00:19:20,480 But the highest mountains of all stretch 1,500 miles 164 00:19:20,600 --> 00:19:23,000 across the north of sub-tropical Asia - 165 00:19:23,120 --> 00:19:25,200 the himalaya. 166 00:19:33,480 --> 00:19:36,720 At the western end, bordering Pakistan, 167 00:19:36,840 --> 00:19:39,040 stand the karakoram. 168 00:19:41,040 --> 00:19:45,400 They contain more peaks over 8,000 metres high 169 00:19:45,520 --> 00:19:47,760 than any other range on earth... 170 00:19:51,960 --> 00:19:53,680 And include k2, 171 00:19:53,800 --> 00:19:57,360 which stands over 8,600 metres tall. 172 00:20:07,040 --> 00:20:08,920 The slopes of the himalaya 173 00:20:09,040 --> 00:20:12,120 carry the greatest accumulation of snow and ice 174 00:20:12,240 --> 00:20:14,760 outside the polar regions. 175 00:20:17,240 --> 00:20:20,520 It's an area known as the third pole. 176 00:20:27,320 --> 00:20:29,920 But north of the himalaya, 177 00:20:30,040 --> 00:20:33,200 there are even more surprising frozen worlds 178 00:20:33,320 --> 00:20:35,400 created by altitude. 179 00:20:40,080 --> 00:20:42,560 A remote snow-bound desert - 180 00:20:42,680 --> 00:20:44,160 the gobi. 181 00:20:52,200 --> 00:20:55,360 And beyond it, a grassy plain that stretches 182 00:20:55,480 --> 00:20:58,520 for 5,000 miles across Central Asia. 183 00:20:59,960 --> 00:21:02,760 It's known as the great steppe. 184 00:21:08,240 --> 00:21:10,280 Here, sheltering from the elements 185 00:21:10,400 --> 00:21:11,800 in his Boulder den, 186 00:21:11,920 --> 00:21:14,360 is a somewhat grouchy resident. 187 00:21:20,720 --> 00:21:22,320 A pallas's cat. 188 00:21:25,120 --> 00:21:28,600 He has the densest fur of any cat in the world. 189 00:21:34,240 --> 00:21:36,400 Nonetheless, to keep warm, 190 00:21:36,520 --> 00:21:40,160 he must catch up to five rodents a day. 191 00:21:48,960 --> 00:21:52,200 Top of the menu are voles... 192 00:21:53,520 --> 00:21:55,480 And gerbils. 193 00:21:59,360 --> 00:22:00,840 Relative to body size, 194 00:22:00,960 --> 00:22:04,960 pallas's cats have one of the shortest legs of any cat... 195 00:22:10,400 --> 00:22:11,960 And that helps by giving them 196 00:22:12,080 --> 00:22:14,640 a low profile when stalking. 197 00:22:16,520 --> 00:22:20,440 But it's not so good for wading through deep snow. 198 00:22:33,560 --> 00:22:36,800 Never mind. There are plenty more. 199 00:22:39,360 --> 00:22:42,880 He just needs to stay focused. 200 00:22:58,840 --> 00:23:02,440 Unfortunately, the longer he's out in the snow, 201 00:23:02,560 --> 00:23:05,560 the colder his paws become. 202 00:23:14,840 --> 00:23:20,320 And he has only one way to get the blood circulating again. 203 00:23:34,560 --> 00:23:37,080 That could be one shake too many. 204 00:23:52,240 --> 00:23:56,240 Only one hunt in three by a pallas's cat is successful. 205 00:23:57,480 --> 00:24:00,200 No wonder he has the reputation of being 206 00:24:00,320 --> 00:24:03,400 the grumpiest cat in the world. 207 00:24:10,800 --> 00:24:13,640 To the north of the steppe, in higher latitudes, 208 00:24:13,760 --> 00:24:16,600 lies yet another frozen world. 209 00:24:22,360 --> 00:24:24,800 The boreal forest. 210 00:24:27,440 --> 00:24:31,640 750 billion snow-covered trees. 211 00:24:38,600 --> 00:24:41,720 It's the largest forest on earth, 212 00:24:41,840 --> 00:24:44,920 encircling the top of the world 213 00:24:45,040 --> 00:24:47,280 from Europe to Russia, 214 00:24:47,400 --> 00:24:49,880 and across to North America. 215 00:24:57,600 --> 00:25:01,680 At the far eastern end of this vast siberian forest 216 00:25:01,800 --> 00:25:06,440 lies the hunting ground of one of the world's rarest big cats. 217 00:25:20,160 --> 00:25:22,240 The siberian tiger. 218 00:25:34,040 --> 00:25:36,680 Ihegalhunfing and destruction of its habitat 219 00:25:36,800 --> 00:25:41,160 have driven this tiger to the very brink of extinction. 220 00:25:42,240 --> 00:25:45,760 Now fewer than 500 remain in the wild. 221 00:25:54,960 --> 00:25:57,800 Weighing nearly 200kg, 222 00:25:57,920 --> 00:26:00,920 it's the largest of all the big cats. 223 00:26:06,680 --> 00:26:07,760 To keep warm, 224 00:26:07,880 --> 00:26:11,840 this male must eat 10kg of meat a day... 225 00:26:15,440 --> 00:26:18,320 But in winter, any prey remaining here... 226 00:26:19,920 --> 00:26:22,960 Is all too easily alarmed. 227 00:26:31,640 --> 00:26:35,320 He must patrol his entire 700-square-mile territory 228 00:26:35,440 --> 00:26:37,880 if he is to find enough to eat. 229 00:26:43,240 --> 00:26:45,120 His acute sense of smell 230 00:26:45,240 --> 00:26:48,000 tells him that wild pig were here. 231 00:26:58,800 --> 00:27:03,760 He's so hungry that he would tackle even a 150kg bear. 232 00:27:07,600 --> 00:27:10,080 But it left here months ago... 233 00:27:11,720 --> 00:27:15,200 Leaving only a faint trace of its scent. 234 00:27:19,640 --> 00:27:22,960 In the Autumn, black bears here escape the coming winter 235 00:27:23,080 --> 00:27:25,600 by hibernating inside caves. 236 00:27:34,360 --> 00:27:37,480 But that wouldn't stop a tiger from trying to catch one. 237 00:27:48,000 --> 00:27:51,680 Remote cameras reveal the bear's whereabouts. 238 00:28:00,320 --> 00:28:04,920 It retreated into the farthest recess months ago. 239 00:28:10,120 --> 00:28:13,000 The tiger is simply too big to reach it. 240 00:28:23,440 --> 00:28:25,920 But ready for every opportunity, 241 00:28:26,040 --> 00:28:30,360 this big cat is able to endure the long siberian winter. 242 00:28:36,560 --> 00:28:40,280 And as long as this forest is kept free from poachers, 243 00:28:40,400 --> 00:28:44,840 these magnificent tigers have a good chance of surviving. 244 00:28:52,880 --> 00:28:56,680 In the northerly reaches of the boreal forest... 245 00:28:58,080 --> 00:29:02,120 A strange phenomenon illuminates the night sky. 246 00:29:05,440 --> 00:29:07,720 The Aurora borealis. 247 00:29:09,960 --> 00:29:13,120 Electrically charged particles from the sun 248 00:29:13,240 --> 00:29:15,160 collide with the earth's atmosphere, 249 00:29:15,280 --> 00:29:18,000 creating this othennorldly display. 250 00:29:25,200 --> 00:29:26,480 Viewed from space, 251 00:29:26,600 --> 00:29:29,720 the Aurora brings light to the frozen Poles, 252 00:29:29,840 --> 00:29:32,600 which otherwise would remain in darkness 253 00:29:32,720 --> 00:29:34,520 for almost three months. 254 00:29:43,760 --> 00:29:46,400 This is the arctic tundra... 255 00:29:49,800 --> 00:29:53,840 Where temperatures can fall to minus 50 degrees celsius. 256 00:29:56,240 --> 00:29:57,800 With little or no shelter, 257 00:29:57,920 --> 00:30:00,440 few animals can survive the winter here. 258 00:30:02,520 --> 00:30:04,080 But some do. 259 00:30:11,480 --> 00:30:13,520 Muskox. 260 00:30:13,640 --> 00:30:16,080 Relics from the last ice age. 261 00:30:19,840 --> 00:30:22,160 Two layers of fur protect them 262 00:30:22,280 --> 00:30:24,920 from temperatures of minus 30 degrees. 263 00:30:29,800 --> 00:30:32,640 This allows them to give birth in early spring. 264 00:30:36,800 --> 00:30:41,440 At six hours old, a calf is already able to stand... 265 00:30:47,320 --> 00:30:51,800 Ready to follow the herd in the search for fresh grazing. 266 00:30:58,360 --> 00:31:00,880 But until they gain in strength, 267 00:31:01,000 --> 00:31:03,880 they are very vulnerable. 268 00:31:13,080 --> 00:31:14,640 They're being stalked. 269 00:31:17,960 --> 00:31:20,040 Grizzly bears. 270 00:31:34,240 --> 00:31:37,320 Weighing up to 300kg, 271 00:31:37,440 --> 00:31:41,440 they have emerged after six months of hibernation... 272 00:31:42,560 --> 00:31:44,560 And are extremely hungry. 273 00:31:50,040 --> 00:31:53,160 One gets to within just ten metres... 274 00:31:54,720 --> 00:31:56,040 And then attacks. 275 00:32:31,760 --> 00:32:33,720 Separated from their mothers, 276 00:32:33,840 --> 00:32:38,240 the newly born are unable to distinguish friend... 277 00:32:39,400 --> 00:32:40,880 From foe. 278 00:32:54,120 --> 00:32:58,280 The bear instinctively kills every calf it can. 279 00:33:03,520 --> 00:33:06,240 Only a few escape. 280 00:33:13,280 --> 00:33:16,160 But the herd is now far away... 281 00:33:20,480 --> 00:33:23,880 And he is too weak to follow. 282 00:33:45,040 --> 00:33:49,840 90% of calves do not survive their first year. 283 00:33:53,240 --> 00:33:54,760 Even one without injury 284 00:33:54,880 --> 00:33:57,640 stands little chance without its mother. 285 00:34:41,040 --> 00:34:42,880 Reunited. 286 00:34:49,000 --> 00:34:52,240 If just a few calves survive to adulthood, 287 00:34:52,360 --> 00:34:56,000 the future of the herd will be secure. 288 00:35:12,000 --> 00:35:15,160 North of the tundra lies the arctic ocean, 289 00:35:15,280 --> 00:35:17,920 surrounded by three continents - 290 00:35:18,040 --> 00:35:21,560 Europe, North America and Asia. 291 00:35:23,920 --> 00:35:27,840 In winter, it remains almost entirely frozen. 292 00:35:31,960 --> 00:35:34,360 But as the spring sunshine finally reaches 293 00:35:34,480 --> 00:35:36,840 the northernmost part of the planet, 294 00:35:36,960 --> 00:35:40,240 the sea ice begins to break up. 295 00:35:42,720 --> 00:35:46,000 This marks the start of the breeding season 296 00:35:46,120 --> 00:35:49,520 for male hooded seals. 297 00:36:01,320 --> 00:36:02,960 When they're six years old, 298 00:36:03,080 --> 00:36:07,000 the males develop an inflatable nose. 299 00:36:09,920 --> 00:36:13,360 They're ready to breed, and the bigger their nose, 300 00:36:13,480 --> 00:36:16,880 the more attractive they will be to a female. 301 00:36:18,120 --> 00:36:21,800 And now this one is eager to prove it. 302 00:36:36,800 --> 00:36:39,760 A female has just given birth. 303 00:36:44,320 --> 00:36:46,800 A mother spends a mere four days 304 00:36:46,920 --> 00:36:48,640 feeding milk to her pup... 305 00:36:51,640 --> 00:36:54,120 And then, and only then, 306 00:36:54,240 --> 00:36:56,760 will she be ready to mate again. 307 00:36:59,640 --> 00:37:03,640 That is too long for an impatient youngster 308 00:37:03,760 --> 00:37:04,960 to wait around. 309 00:37:18,040 --> 00:37:21,440 These females seem to have been claimed 310 00:37:21,560 --> 00:37:23,200 by a larger male... 311 00:37:24,560 --> 00:37:28,120 But if this youngster is to breed this year, 312 00:37:28,240 --> 00:37:29,680 it's worth a try. 313 00:37:39,320 --> 00:37:42,760 An inflatable nose can also be used 314 00:37:42,880 --> 00:37:44,920 to intimidate a rival. 315 00:37:46,880 --> 00:37:50,000 His bravado pays off. 316 00:37:55,160 --> 00:37:58,800 He must now woo the receptive female. 317 00:38:17,280 --> 00:38:19,160 She seems unimpressed... 318 00:38:21,960 --> 00:38:24,680 But he has another trick. 319 00:38:34,040 --> 00:38:39,320 He has an expandable sac within his left nostril. 320 00:38:53,480 --> 00:38:55,040 What is her verdict? 321 00:39:02,880 --> 00:39:04,680 A sharp nip on the tail. 322 00:39:08,600 --> 00:39:11,400 And that means no. 323 00:39:17,160 --> 00:39:19,800 With only one day in the year in which to mate, 324 00:39:19,920 --> 00:39:22,840 the female is understandably choosy... 325 00:39:26,680 --> 00:39:28,720 And until the youngster has grown 326 00:39:28,840 --> 00:39:30,960 a more impressive balloon, 327 00:39:31,080 --> 00:39:33,120 he's unlikely to be chosen. 328 00:39:35,520 --> 00:39:38,480 No wonder he's deflated. 329 00:39:47,120 --> 00:39:50,320 The spring not only transforms the ocean, 330 00:39:50,440 --> 00:39:52,920 it also triggers an important event 331 00:39:53,040 --> 00:39:55,840 on the biggest of the arctic's islands. 332 00:39:58,240 --> 00:39:59,520 Greenland. 333 00:39:59,640 --> 00:40:02,120 Over 1,600 miles long. 334 00:40:09,320 --> 00:40:13,280 It's covered by a single gigantic ice sheet, 335 00:40:13,400 --> 00:40:15,720 the largest in the northern hemisphere. 336 00:40:22,920 --> 00:40:26,680 As spring advances, the surface of the ice melts, 337 00:40:26,800 --> 00:40:29,600 forming crystal-clear lakes... 338 00:40:30,880 --> 00:40:32,960 Up to five miles wide. 339 00:40:38,240 --> 00:40:41,040 Climate change is bringing higher temperatures, 340 00:40:41,160 --> 00:40:44,200 so there is more and more meltwater. 341 00:40:46,280 --> 00:40:50,040 It drains down into the mile-thick ice sheet... 342 00:40:51,520 --> 00:40:55,720 And a whole chain of events is then triggered. 343 00:40:57,600 --> 00:41:00,320 Time-lapse photography from space 344 00:41:00,440 --> 00:41:02,400 reveals what happens next. 345 00:41:10,640 --> 00:41:12,560 The increased meltwater 346 00:41:12,680 --> 00:41:16,400 accelerates the ice sheet's slide downhill. 347 00:41:27,800 --> 00:41:29,960 Eventually, it reaches the ocean. 348 00:42:15,520 --> 00:42:18,080 Here, it breaks up into icebergs, 349 00:42:18,200 --> 00:42:21,960 some taller than the empire state building. 350 00:42:55,280 --> 00:42:57,480 Greenland is losing its ice 351 00:42:57,600 --> 00:43:01,480 six times faster today than it was 30 years ago. 352 00:43:05,200 --> 00:43:07,480 It alone is responsible 353 00:43:07,600 --> 00:43:10,960 for a quarter of the rise in global sea levels. 354 00:43:22,640 --> 00:43:25,640 Changes in the arctic are already affecting 355 00:43:25,760 --> 00:43:29,360 the lives of its highly specialised wildlife. 356 00:43:36,320 --> 00:43:37,880 Polar bears. 357 00:43:43,440 --> 00:43:46,880 These one-year-old twins still rely on their mother 358 00:43:47,000 --> 00:43:52,320 for her milk, protection and crucial survival lessons. 359 00:44:14,520 --> 00:44:18,720 But they have yet to perfect their swimming technique... 360 00:44:21,400 --> 00:44:24,960 And they can't wait to practise. 361 00:44:34,520 --> 00:44:37,880 The cubs need to be as at home in the water 362 00:44:38,000 --> 00:44:39,800 as they are on the sea ice. 363 00:44:51,160 --> 00:44:53,920 Their mother calls them out. 364 00:44:55,480 --> 00:44:56,800 Until they've accumulated 365 00:44:56,920 --> 00:44:59,160 a significant layer of body fat... 366 00:45:00,240 --> 00:45:02,720 They feel the cold. 367 00:45:04,400 --> 00:45:08,000 A roll in the snow is a good way to dry off. 368 00:45:13,800 --> 00:45:16,240 Then it's back to play... 369 00:45:19,840 --> 00:45:22,400 While their mother heads off to hunt. 370 00:45:28,440 --> 00:45:30,080 Over the coming months, 371 00:45:30,200 --> 00:45:35,200 a mother must provide her cubs with not just milk but meat, 372 00:45:35,320 --> 00:45:37,080 and lots of it. 373 00:45:41,920 --> 00:45:45,760 By midsummer, the sea ice has become so thin... 374 00:45:51,040 --> 00:45:54,600 That her best chance of catching her preferred prey 375 00:45:54,720 --> 00:45:59,160 is by ambushing it from the water. 376 00:46:11,280 --> 00:46:14,200 It's a technique known as aquatic stalking. 377 00:46:19,360 --> 00:46:21,760 She approaches downwind... 378 00:46:23,520 --> 00:46:29,160 And tries to get within a metre of a bearded seal. 379 00:46:37,520 --> 00:46:41,280 But today there is less sea ice to provide cover, 380 00:46:41,400 --> 00:46:46,640 so she is having to target riskier prey. 381 00:46:49,960 --> 00:46:52,240 The hooded seal. 382 00:47:03,240 --> 00:47:05,760 They are about the same size as the bearded, 383 00:47:05,880 --> 00:47:09,360 but more aggressive and dangerous. 384 00:47:45,720 --> 00:47:49,560 She moves round to the other side. 385 00:48:17,600 --> 00:48:21,520 The arctic is now warming more than twice as fast 386 00:48:21,640 --> 00:48:23,560 as the rest of the world. 387 00:48:25,120 --> 00:48:27,640 The sea could be ice free in summer 388 00:48:27,760 --> 00:48:31,680 by as early as 2035. 389 00:48:37,880 --> 00:48:40,520 That will make it harder for mother polar bears 390 00:48:40,640 --> 00:48:42,320 to feed themselves... 391 00:48:43,520 --> 00:48:45,280 Let alone their cubs. 392 00:48:52,440 --> 00:48:55,040 Well adapted to live in the cold... 393 00:48:57,320 --> 00:49:00,840 The animals that inhabit our frozen lands and seas 394 00:49:00,960 --> 00:49:04,160 need one thing more than any other. 395 00:49:10,520 --> 00:49:15,640 And that is for the planet to stop warming. 396 00:49:29,600 --> 00:49:33,640 It's now up to us to make that happen. 397 00:49:52,320 --> 00:49:55,160 Filming across the length and breadth 398 00:49:55,280 --> 00:49:57,160 of our frozen planet, 399 00:49:57,280 --> 00:49:59,880 one of the team's greatest challenges was to capture 400 00:50:00,000 --> 00:50:04,080 the enormity of Greenland's rapidly melting ice sheet. 401 00:50:07,400 --> 00:50:08,920 To do so, the crew launched 402 00:50:09,040 --> 00:50:12,360 five separate filming expeditions, 403 00:50:12,480 --> 00:50:16,760 installing specially designed cold-proof time-lapse cameras 404 00:50:16,880 --> 00:50:19,520 that were to run for three years... 405 00:50:24,640 --> 00:50:27,120 Even commissioning satellites to record 406 00:50:27,240 --> 00:50:29,720 the big-picture changes. 407 00:50:32,680 --> 00:50:34,760 But the story would be incomplete 408 00:50:34,880 --> 00:50:37,680 without documenting the finale of this event - 409 00:50:37,800 --> 00:50:40,840 the calving of Greenland's store glacier... 410 00:50:42,400 --> 00:50:45,360 A wall of ice over three miles long... 411 00:50:46,840 --> 00:50:50,120 And towering 120 metres high. 412 00:50:55,680 --> 00:50:58,800 The crew arrive at the height of the summer thaw, 413 00:50:58,920 --> 00:51:00,400 when, at any moment, 414 00:51:00,520 --> 00:51:04,200 fracturing ice blocks the size of a small town 415 00:51:04,320 --> 00:51:06,120 may be cast into the sea. 416 00:51:12,000 --> 00:51:14,000 Camping out for the next three weeks, 417 00:51:14,120 --> 00:51:17,480 the team takes advantage of the constant daylight 418 00:51:17,600 --> 00:51:20,400 offered by the far north at this time of the year. 419 00:51:23,920 --> 00:51:26,920 We've got a lot of ice on the glacier, 24 hours a day. 420 00:51:27,040 --> 00:51:29,240 So, yeah, we're poised. 421 00:51:30,560 --> 00:51:32,760 I started about 8pm 422 00:51:32,880 --> 00:51:34,880 and it's currently, yeah, just after two. 423 00:51:35,000 --> 00:51:37,840 I've got until 4am this morning, I think. 424 00:51:42,560 --> 00:51:45,000 They're hoping to be one of the first film crews 425 00:51:45,120 --> 00:51:47,280 to uso a camera drone 426 00:51:47,400 --> 00:51:50,680 for unprecedented proximity and a brand-new perspective. 427 00:51:50,800 --> 00:51:52,680 Yeah, it's going. 428 00:51:52,800 --> 00:51:55,880 It's not long before their new technology 429 00:51:56,000 --> 00:51:58,640 is put to the test. 430 00:52:00,560 --> 00:52:03,680 But it quickly reveals its limitations. 431 00:52:08,160 --> 00:52:10,920 The issue with the drone, you've got to turn it on, 432 00:52:11,040 --> 00:52:14,520 get it in the air and fly it 1.5km to the glacier fronts. 433 00:52:15,760 --> 00:52:18,200 So, if you see a calving happening, 434 00:52:18,320 --> 00:52:20,320 then you're too late. 435 00:52:21,480 --> 00:52:23,600 With a flight time of just 20 minutes, 436 00:52:23,720 --> 00:52:27,080 gauging the moment of takeoff is critical. 437 00:52:27,200 --> 00:52:28,440 Helen: Yeah, I feel like today, 438 00:52:28,560 --> 00:52:31,520 just every decision I've made has been the wrong one. 439 00:52:31,640 --> 00:52:33,720 It's really easy to trick yourself into thinking, 440 00:52:33,840 --> 00:52:35,200 "oh, it's gonna go, it's gonna go," 441 00:52:35,320 --> 00:52:36,320 so you get out there, 442 00:52:36,360 --> 00:52:38,000 use up a whole drone battery hovenng, 443 00:52:38,120 --> 00:52:41,560 come back, and as you're heading back - pfff! 444 00:52:43,720 --> 00:52:46,040 Soon, the team face another problem 445 00:52:46,160 --> 00:52:49,200 that comes with today's warming arctic. 446 00:52:51,880 --> 00:52:53,400 Unseasonably wet weather 447 00:52:53,520 --> 00:52:56,400 makes it impossible to fly the drone, 448 00:52:56,520 --> 00:52:59,720 and acts as a catalyst for further melting. 449 00:53:03,920 --> 00:53:09,080 Absolute racket happening down in the glacier. 450 00:53:09,200 --> 00:53:10,200 Oh, my goodness. 451 00:53:13,440 --> 00:53:15,400 Even if it is a major calving event... 452 00:53:18,000 --> 00:53:19,280 Can't see a thing. 453 00:53:23,160 --> 00:53:25,800 That sound just went on and on. 454 00:53:30,360 --> 00:53:32,200 Helen: That one was huge. 455 00:53:35,320 --> 00:53:37,800 After five days of frustration, 456 00:53:37,920 --> 00:53:41,480 the fog finally lifts to reveal the bay 457 00:53:41,600 --> 00:53:43,760 choked with giant icebergs. 458 00:53:45,920 --> 00:53:49,680 It appears the crew have missed their opportunity. 459 00:53:56,280 --> 00:53:58,520 The morale of the crew 460 00:53:58,640 --> 00:54:01,240 has taken a little bit of a downturn. 461 00:54:01,360 --> 00:54:04,480 Do you know what? I just don't know what to say. 462 00:54:04,600 --> 00:54:06,560 I'm so tired. 463 00:54:06,680 --> 00:54:08,120 To make matters worse, 464 00:54:08,240 --> 00:54:11,120 a plague of mosquitoes descends, 465 00:54:11,240 --> 00:54:13,840 further disheartening the exhausted team. 466 00:54:20,000 --> 00:54:22,240 Helen: All your senses are all-go all the time, 467 00:54:22,360 --> 00:54:24,320 even when you're trying to sleep, 468 00:54:24,440 --> 00:54:25,880 so it's just... 469 00:54:26,000 --> 00:54:28,400 A bit emotionally draining sometimes. 470 00:54:34,880 --> 00:54:37,640 Then, with just a few shooting days left, 471 00:54:37,760 --> 00:54:39,720 under a warming sun, 472 00:54:39,840 --> 00:54:44,320 the glacier groans and rumbles back into action. 473 00:54:48,640 --> 00:54:50,840 Ooh. 474 00:54:52,800 --> 00:54:54,280 Man: Guys, a big one going! 475 00:54:55,320 --> 00:54:58,520 This could be the opportunity they've been waiting for. 476 00:55:00,320 --> 00:55:03,040 Oh, my gosh, look at that! Ah! 477 00:55:13,520 --> 00:55:15,960 A calving event lasting long enough 478 00:55:16,080 --> 00:55:17,360 to film from the drone. 479 00:55:20,080 --> 00:55:23,560 But no-one is prepared for the sheer scale of it. 480 00:55:31,240 --> 00:55:34,960 Just layer after layer of ice broke away 481 00:55:35,080 --> 00:55:36,160 and fell into the sea, 482 00:55:36,280 --> 00:55:37,680 and then out came 483 00:55:37,800 --> 00:55:40,760 this enormous, skyscraper-sized iceberg, 484 00:55:40,880 --> 00:55:44,160 displacing vast quantities of water 485 00:55:44,280 --> 00:55:46,680 and throwing enormous blocks of ice around 486 00:55:46,800 --> 00:55:48,080 like they were nothing. 487 00:55:50,360 --> 00:55:53,120 Sitting here, day after day, crossing your fingers 488 00:55:53,240 --> 00:55:54,760 and hoping that you get a big calving 489 00:55:54,880 --> 00:55:56,616 and you see a big event, and you manage to film it, 490 00:55:56,640 --> 00:55:58,840 and when it does happen and when it does go off, 491 00:55:58,960 --> 00:56:01,080 it's so exciting, and you get the adrenaline. 492 00:56:01,200 --> 00:56:03,280 And then aftennards, as you're sort of coming down 493 00:56:03,400 --> 00:56:05,120 from that, there is a bitter sweetness to it 494 00:56:05,200 --> 00:56:06,920 as she realised that's another piece of ice 495 00:56:07,040 --> 00:56:09,560 that's slowly raising the sea level. 496 00:56:13,200 --> 00:56:17,080 Such imagery provides an invaluable record 497 00:56:17,200 --> 00:56:18,720 of the rapid changes 498 00:56:18,840 --> 00:56:20,360 that are now taking place 499 00:56:20,480 --> 00:56:23,240 across our frozen planet.