WEBVTT 99:59:59.999 --> 99:59:59.999 In 1956, 99:59:59.999 --> 99:59:59.999 a documentary by Jacque Cousteau won both the Palm d'Or 99:59:59.999 --> 99:59:59.999 and an Oscar award. 99:59:59.999 --> 99:59:59.999 This film was called "Le Monde de Silence," 99:59:59.999 --> 99:59:59.999 or, "The Silent World." 99:59:59.999 --> 99:59:59.999 And the premise of the title 99:59:59.999 --> 99:59:59.999 was that the underwater world was a quiet world. 99:59:59.999 --> 99:59:59.999 We now know 60 years later 99:59:59.999 --> 99:59:59.999 that the underwater world is anything but silent. 99:59:59.999 --> 99:59:59.999 Although the sounds are inaudible above water 99:59:59.999 --> 99:59:59.999 depending on where you are and the time of year, 99:59:59.999 --> 99:59:59.999 the underwater soundscape can be as noisy as any jungle or rainforest. 99:59:59.999 --> 99:59:59.999 Invertebrates like snapping shrimp, fish and marine mammals 99:59:59.999 --> 99:59:59.999 all use sound. 99:59:59.999 --> 99:59:59.999 They use sound to study their habitat, 99:59:59.999 --> 99:59:59.999 to keep in communication with each other, 99:59:59.999 --> 99:59:59.999 to navigate, 99:59:59.999 --> 99:59:59.999 to detect predators and prey. 99:59:59.999 --> 99:59:59.999 And they also use sound by listening to know something about their environment. 99:59:59.999 --> 99:59:59.999 Take for an example, the arctic. 99:59:59.999 --> 99:59:59.999 It's considered a vast, inhospitable place, 99:59:59.999 --> 99:59:59.999 sometimes described as a desert 99:59:59.999 --> 99:59:59.999 because it is so cold and so remote, 99:59:59.999 --> 99:59:59.999 and ice-covered much of the year. 99:59:59.999 --> 99:59:59.999 And despite this, 99:59:59.999 --> 99:59:59.999 there is no place on Earth that I would rather be than the Arctic, 99:59:59.999 --> 99:59:59.999 especially as days lengthen and spring comes. 99:59:59.999 --> 99:59:59.999 To me, 99:59:59.999 --> 99:59:59.999 the Arctic really embodies this disconnect between what we see on the surface 99:59:59.999 --> 99:59:59.999 and what's going on under water. 99:59:59.999 --> 99:59:59.999 You can look out across the ice, 99:59:59.999 --> 99:59:59.999 all white and blue and cold, 99:59:59.999 --> 99:59:59.999 and see nothing. 99:59:59.999 --> 99:59:59.999 But if you could hear underwater, 99:59:59.999 --> 99:59:59.999 the sounds you would hear would at first amaze 99:59:59.999 --> 99:59:59.999 and then delight you. 99:59:59.999 --> 99:59:59.999 And while your eyes are seeing nothing for kilometers but ice, 99:59:59.999 --> 99:59:59.999 your ears are telling you that out there are bowhead and beluga whales, 99:59:59.999 --> 99:59:59.999 walrus and beared deals. 99:59:59.999 --> 99:59:59.999 The ice, too, makes sounds. 99:59:59.999 --> 99:59:59.999 It screeches and cracks and pops and groans 99:59:59.999 --> 99:59:59.999 as it collides and rubs when temperature or currents and winds change. 99:59:59.999 --> 99:59:59.999 And under 100 percent sea ice in the dead of winter, 99:59:59.999 --> 99:59:59.999 Bowhead whales are singing. 99:59:59.999 --> 99:59:59.999 And you would never expect that 99:59:59.999 --> 99:59:59.999 because we humans, 99:59:59.999 --> 99:59:59.999 we tend to be very visual animals. 99:59:59.999 --> 99:59:59.999 For most of us -- 99:59:59.999 --> 99:59:59.999 but not all -- 99:59:59.999 --> 99:59:59.999 our sense of sight is how we navigate our world. 99:59:59.999 --> 99:59:59.999 For marine mammals that live underwater, 99:59:59.999 --> 99:59:59.999 where chemical cues and light transmit poorly, 99:59:59.999 --> 99:59:59.999 sound is the sense by which they see. 99:59:59.999 --> 99:59:59.999 And sound transmits very well under water, 99:59:59.999 --> 99:59:59.999 much better than it does in air, 99:59:59.999 --> 99:59:59.999 so signals can be heard over great distances. 99:59:59.999 --> 99:59:59.999 In the Arctic, 99:59:59.999 --> 99:59:59.999 this is especially important 99:59:59.999 --> 99:59:59.999 because not only do Arctic marine mammals have to hear each other, 99:59:59.999 --> 99:59:59.999 but they also have to listen for cues in the environment 99:59:59.999 --> 99:59:59.999 that might indicate heavy ice ahead or open water. 99:59:59.999 --> 99:59:59.999 Remember, although they spend most of their lives underwater, 99:59:59.999 --> 99:59:59.999 they are mammals, 99:59:59.999 --> 99:59:59.999 and so they have to surface to breathe. 99:59:59.999 --> 99:59:59.999 So they might listen for thin ice or no ice, 99:59:59.999 --> 99:59:59.999 or listen for echoes off nearby ice. 99:59:59.999 --> 99:59:59.999 Arctic marine animals live in a rich and very underwater soundscape. 99:59:59.999 --> 99:59:59.999 In the spring, 99:59:59.999 --> 99:59:59.999 it can be a cacophony of sound. 99:59:59.999 --> 99:59:59.999 (Arctic sound) 99:59:59.999 --> 99:59:59.999 But when the ice is frozen solid, 99:59:59.999 --> 99:59:59.999 and there are no big temperature shifts or current changes, 99:59:59.999 --> 99:59:59.999 the underwater Arctic has some of the lowest ambient noise levels 99:59:59.999 --> 99:59:59.999 of the world's oceans. 99:59:59.999 --> 99:59:59.999 But this is changing. 99:59:59.999 --> 99:59:59.999 This is primarily due to a decrease in seasonal sea ice, 99:59:59.999 --> 99:59:59.999 which is a direct result of human greenhouse gas emissions. 99:59:59.999 --> 99:59:59.999 We are in effect, 99:59:59.999 --> 99:59:59.999 with climate change, 99:59:59.999 --> 99:59:59.999 conducting a completely uncontrolled experiment with our planet. 99:59:59.999 --> 99:59:59.999 Over the past 30 years, 99:59:59.999 --> 99:59:59.999 areas of the Arctic have seen decreases in seasonal sea ice 99:59:59.999 --> 99:59:59.999 from anywhere from six weeks to four months. 99:59:59.999 --> 99:59:59.999 This decrease in sea ice is sometimes referred to as an increase 99:59:59.999 --> 99:59:59.999 in the open water season. 99:59:59.999 --> 99:59:59.999 That is the time of year when the Arctic is navigatable to vessels. 99:59:59.999 --> 99:59:59.999 And not only is the extent of ice changing, 99:59:59.999 --> 99:59:59.999 but the age and the width of ice is, too. 99:59:59.999 --> 99:59:59.999 Now, you may well have heard 99:59:59.999 --> 99:59:59.999 that a decrease in sea ice is causing a loss of habitat for animals 99:59:59.999 --> 99:59:59.999 that rely on sea ice, 99:59:59.999 --> 99:59:59.999 such as ice seals, or walrus, or polar bears. 99:59:59.999 --> 99:59:59.999 Decreasing sea ice is also causing increased erosion 99:59:59.999 --> 99:59:59.999 along coastal villages, 99:59:59.999 --> 99:59:59.999 and changing prey availability from marine birds and mammals. 99:59:59.999 --> 99:59:59.999 Climate change and decreases in sea ice 99:59:59.999 --> 99:59:59.999 are also altering the underwater sound scape of the Arctic. 99:59:59.999 --> 99:59:59.999 What do I mean by soundscape? 99:59:59.999 --> 99:59:59.999 Those of us who eavesdrop on the oceans for a living 99:59:59.999 --> 99:59:59.999 use instruments called hydrophones, 99:59:59.999 --> 99:59:59.999 which are underwater microphones, 99:59:59.999 --> 99:59:59.999 and we record ambient noise -- 99:59:59.999 --> 99:59:59.999 the noise all around us. 99:59:59.999 --> 99:59:59.999 And the soundscape describes the different contributors 99:59:59.999 --> 99:59:59.999 to this noise field. 99:59:59.999 --> 99:59:59.999 What we are hearing on our hydrophones 99:59:59.999 --> 99:59:59.999 are the very real sounds of climate change. 99:59:59.999 --> 99:59:59.999 We are hearing these changes from three fronts: 99:59:59.999 --> 99:59:59.999 from the air, 99:59:59.999 --> 99:59:59.999 from the water 99:59:59.999 --> 99:59:59.999 and from land. 99:59:59.999 --> 99:59:59.999 First, air. 99:59:59.999 --> 99:59:59.999 Wind on water creates waves. 99:59:59.999 --> 99:59:59.999 These waves make bubbles; 99:59:59.999 --> 99:59:59.999 the bubbles break. 99:59:59.999 --> 99:59:59.999 And when they do, 99:59:59.999 --> 99:59:59.999 they make noise. 99:59:59.999 --> 99:59:59.999 And this noise is like a hiss or a static in the background. 99:59:59.999 --> 99:59:59.999 In the Arctic when it's ice-covered, 99:59:59.999 --> 99:59:59.999 most of the noise from wind doesn't make it into the water column 99:59:59.999 --> 99:59:59.999 because they ice acts as a buffer between the atmosphere and the water. 99:59:59.999 --> 99:59:59.999 And this is one of the reasons 99:59:59.999 --> 99:59:59.999 that the Arctic can have very low ambient noise levels. 99:59:59.999 --> 99:59:59.999 But with decreases in seasonal sea ice, 99:59:59.999 --> 99:59:59.999 not only is the Artic now open to this wave noise, 99:59:59.999 --> 99:59:59.999 but the number storms 99:59:59.999 --> 99:59:59.999 and the intensity of storms in the Arctic has been increasing. 99:59:59.999 --> 99:59:59.999 All of this is raising noise levels in a previously quiet ocean. 99:59:59.999 --> 99:59:59.999 Second -- 99:59:59.999 --> 99:59:59.999 water. 99:59:59.999 --> 99:59:59.999 With less seasonal sea ice, 99:59:59.999 --> 99:59:59.999 sub-Arctic species are moving North, 99:59:59.999 --> 99:59:59.999 and taking advantage of the new habitat that is created by more open water. 99:59:59.999 --> 99:59:59.999 Now, Arctic whales, 99:59:59.999 --> 99:59:59.999 like this Bowhead, 99:59:59.999 --> 99:59:59.999 they have no dorsal fin 99:59:59.999 --> 99:59:59.999 because they have evolved to live and swim in ice-covered waters, 99:59:59.999 --> 99:59:59.999 and having something sticking off of your back is not very conducive 99:59:59.999 --> 99:59:59.999 to migrating through ice, 99:59:59.999 --> 99:59:59.999 and may, in fact, be excluding animals from the ice. 99:59:59.999 --> 99:59:59.999 But now, everywhere we've listened, 99:59:59.999 --> 99:59:59.999 we're hearing the sounds of Fin whales and Humpback whales 99:59:59.999 --> 99:59:59.999 and Killer whales, 99:59:59.999 --> 99:59:59.999 further and further North, 99:59:59.999 --> 99:59:59.999 and later and later in the season. 99:59:59.999 --> 99:59:59.999 We are hearing, in essence, 99:59:59.999 --> 99:59:59.999 an invasion of the Arctic by sub-Arctic species. 99:59:59.999 --> 99:59:59.999 And we don't know what this means. 99:59:59.999 --> 99:59:59.999 Will there be competition for food 99:59:59.999 --> 99:59:59.999 between Arctic and sub-Arctic animals? 99:59:59.999 --> 99:59:59.999 Might this sub-Arctic species introduce diseases 99:59:59.999 --> 99:59:59.999 or parasites into the Arctic? 99:59:59.999 --> 99:59:59.999 And what are the new sounds that they are producing 99:59:59.999 --> 99:59:59.999 doing to the soundscape under water? 99:59:59.999 --> 99:59:59.999 And third -- 99:59:59.999 --> 99:59:59.999 land. 99:59:59.999 --> 99:59:59.999 And by land, I mean people. 99:59:59.999 --> 99:59:59.999 More open water means increased human use of the Arctic. 99:59:59.999 --> 99:59:59.999 Just this past summer, 99:59:59.999 --> 99:59:59.999 a massive cruise ship made its way through the Northwest passage -- 99:59:59.999 --> 99:59:59.999 the once mythical route between Europe and the Pacific. 99:59:59.999 --> 99:59:59.999 Decreases in sea ice have allowed humans to occupy the Arctic more often. 99:59:59.999 --> 99:59:59.999 It has allowed increases in oil and gas exploration and extraction, 99:59:59.999 --> 99:59:59.999 the potential for commercial shipping, 99:59:59.999 --> 99:59:59.999 as well as increased tourism. 99:59:59.999 --> 99:59:59.999 And we now know that ship noise increases levels of stress hormones in whales, 99:59:59.999 --> 99:59:59.999 and can disrupt feeding behavior. 99:59:59.999 --> 99:59:59.999 Air guns, 99:59:59.999 --> 99:59:59.999 which produce loud, low-frequency "whoomps" 99:59:59.999 --> 99:59:59.999 every 10 to 20 seconds, 99:59:59.999 --> 99:59:59.999 changed the swimming and vocal behavior of whales. 99:59:59.999 --> 99:59:59.999 And all of these sound sources are decreasing the acoustic space 99:59:59.999 --> 99:59:59.999 over which Arctic marine mammals can communicate. 99:59:59.999 --> 99:59:59.999 Now, Arctic marine mammals are used to very high levels of noise 99:59:59.999 --> 99:59:59.999 at certain times of the year. 99:59:59.999 --> 99:59:59.999 But this is primarily from other animals or from sea ice, 99:59:59.999 --> 99:59:59.999 and these are the sounds with which they've evolved, 99:59:59.999 --> 99:59:59.999 and these are sounds that are vital to their very survival. 99:59:59.999 --> 99:59:59.999 These new sounds are loud and they're alien. 99:59:59.999 --> 99:59:59.999 They might impact the environment in ways that we think we understand, 99:59:59.999 --> 99:59:59.999 but also in ways that we don't. 99:59:59.999 --> 99:59:59.999 Remember, sound is the most important sense for these animals. 99:59:59.999 --> 99:59:59.999 And not only is the physical habitat of the Arctic changing rapidly, 99:59:59.999 --> 99:59:59.999 but the acoustic habitat is, too. 99:59:59.999 --> 99:59:59.999 It's as if we've plucked these animals up from the quiet countryside 99:59:59.999 --> 99:59:59.999 and dropped them into a big city in the middle of rush hour. 99:59:59.999 --> 99:59:59.999 And they can't espcape it. 99:59:59.999 --> 99:59:59.999 So what can we do now? 99:59:59.999 --> 99:59:59.999 We can't decrease wind speeds 99:59:59.999 --> 99:59:59.999 or keep sub-Arctic animals from migrating north, 99:59:59.999 --> 99:59:59.999 but we can work on local solutions 99:59:59.999 --> 99:59:59.999 to reducing human-caused underwater noise. 99:59:59.999 --> 99:59:59.999 One of these solutions is to slow down ships 99:59:59.999 --> 99:59:59.999 that traverse the Arctic, 99:59:59.999 --> 99:59:59.999 because a slower ship is a quieter ship. 99:59:59.999 --> 99:59:59.999 We can restrict access in seasons and regions 99:59:59.999 --> 99:59:59.999 that are important for mating, or feeding or migrating. 99:59:59.999 --> 99:59:59.999 We can get smarter about quieting ships, 99:59:59.999 --> 99:59:59.999 and find better ways to explore the ocean bottom. 99:59:59.999 --> 99:59:59.999 And the good news is, 99:59:59.999 --> 99:59:59.999 there are people working on this right now. 99:59:59.999 --> 99:59:59.999 But ultimately, 99:59:59.999 --> 99:59:59.999 we humans have to do the hard work 99:59:59.999 --> 99:59:59.999 of reversing or at the very least decelerating 99:59:59.999 --> 99:59:59.999 human-caused atmospheric changes. 99:59:59.999 --> 99:59:59.999 So let's return to this idea of a silent world under water. 99:59:59.999 --> 99:59:59.999 It's entirely possible 99:59:59.999 --> 99:59:59.999 that many of the whales swimming in the Arctic today, 99:59:59.999 --> 99:59:59.999 especially long-lived species like the bowhead whale 99:59:59.999 --> 99:59:59.999 that the Inuits say can live two human lives -- 99:59:59.999 --> 99:59:59.999 it's possible that these whales were alive in 1956 99:59:59.999 --> 99:59:59.999 when Jacques Cousteau made his film. 99:59:59.999 --> 99:59:59.999 And in retrospect, 99:59:59.999 --> 99:59:59.999 considering all the noise we are creating in the oceans today, 99:59:59.999 --> 99:59:59.999 perhaps it really was "The Silent World." 99:59:59.999 --> 99:59:59.999 Thank you. 99:59:59.999 --> 99:59:59.999 (Applause)