1 00:00:00,000 --> 00:00:00,520 [MUSIC] 2 00:00:00,520 --> 00:00:05,040 Something strange has been happening to the beaches across the Caribbean in recent years. 3 00:00:05,480 --> 00:00:08,920 Large amounts of a brown seaweed, called Sargassum, 4 00:00:09,120 --> 00:00:11,600 have been washing up on shorelines. 5 00:00:11,600 --> 00:00:15,000 Normally found in the open ocean, Sargassum causes 6 00:00:15,000 --> 00:00:18,840 a whole host of issues for coastal ecosystems and communities. 7 00:00:19,480 --> 00:00:22,360 So where is this seaweed coming from? 8 00:00:22,360 --> 00:00:24,080 Let's find out. 9 00:00:24,080 --> 00:00:29,080 Historically, Sargassum was found in scattered patches outside its main range. 10 00:00:29,360 --> 00:00:31,560 But then something strange happened. 11 00:00:31,560 --> 00:00:37,160 In the winter of 2009 to 2010, unusual wind patterns pushed water eastward 12 00:00:37,160 --> 00:00:40,720 from the Sargasso Sea towards the Strait of Gibraltar, where a portion 13 00:00:40,720 --> 00:00:44,680 was transported southward by the Canary Current along the coast of Africa, 14 00:00:45,080 --> 00:00:48,600 delivering a large Sargassum population to the tropical Atlantic, 15 00:00:48,640 --> 00:00:51,640 where it thrived on nutrients from various sources. 16 00:00:51,680 --> 00:00:55,440 This established a new, separate, population of the seaweed 17 00:00:55,640 --> 00:00:57,160 and gave rise to... 18 00:00:57,160 --> 00:01:00,101 ROY: The Great Atlantic Sargassum Belt 19 00:01:00,101 --> 00:01:01,728 That's Roy Armstrong, a professor 20 00:01:01,760 --> 00:01:05,240 in the Department of Marine Sciences at the University of Puerto Rico. 21 00:01:05,680 --> 00:01:09,200 Roy has been trying to figure out the impacts of Sargassum blooms 22 00:01:09,200 --> 00:01:11,800 that have been washing up on Caribbean coastlines. 23 00:01:11,800 --> 00:01:16,240 ROY: Sargassum is an essential habitat in the open ocean. 24 00:01:16,400 --> 00:01:19,360 Think of it as an oasis in the middle of the desert, 25 00:01:19,360 --> 00:01:23,680 it provides shelter, for turtles, for many fishes. 26 00:01:23,840 --> 00:01:28,360 VO: Problem is, when fueled by excess nutrients, Sargassum can quickly grow 27 00:01:28,360 --> 00:01:32,480 and upend the ecology around the islands, which can have negative consequences 28 00:01:32,480 --> 00:01:35,480 for near-shore communities and their economies. 29 00:01:35,680 --> 00:01:39,960 One of the biggest threats is the pungent and toxic hydrogen sulfide 30 00:01:39,960 --> 00:01:43,920 gas that Sargassum releases when it decomposes on shorelines. 31 00:01:44,640 --> 00:01:48,760 There is so much Sargassum that now regularly washes up on the coast, 32 00:01:48,920 --> 00:01:51,880 that local governments are searching for ways to estimate 33 00:01:51,880 --> 00:01:55,640 the size and location of blooms - and their trajectories, 34 00:01:55,840 --> 00:01:58,840 so they can better predict when it will reach the shoreline. 35 00:01:59,680 --> 00:02:02,520 ROY: Because, we cannot deal with all the Sargassum. 36 00:02:02,520 --> 00:02:08,040 So what we need is to prioritize - if you can track with satellites 37 00:02:08,480 --> 00:02:11,720 a patch that you know is going to impact 38 00:02:12,080 --> 00:02:16,440 a very sensitive area, then you know that that's the highest priority. 39 00:02:16,440 --> 00:02:20,120 Now you want to intercept that Sargassum before it comes to shore. 40 00:02:20,360 --> 00:02:24,240 VO: Computer models can rewind the clock to see how currents transport water 41 00:02:24,240 --> 00:02:28,720 across the Atlantic, and help researchers piece together where blooms originate. 42 00:02:30,200 --> 00:02:32,760 Additionally, instruments on NASA satellites 43 00:02:32,760 --> 00:02:36,720 can detect the signatures of large blooms as they move across the ocean. 44 00:02:37,000 --> 00:02:40,640 ROY: The remote sensing technology of NASA is very important 45 00:02:40,640 --> 00:02:43,920 first, to detect Sargassum, and then to track it. 46 00:02:44,400 --> 00:02:48,200 And this way we will have a pretty good idea if 47 00:02:48,200 --> 00:02:53,280 a large patch has the potential of coming to the coast and accumulating, 48 00:02:53,600 --> 00:02:57,496 and therefore impacting the marine ecosystems. 49 00:02:57,496 --> 00:02:58,720 VO: PACE, one of NASA's 50 00:02:58,720 --> 00:02:58,760 and therefore impacting the marine ecosystems Pace, one of NASA's 51 00:02:58,760 --> 00:03:02,400 newest satellites, can add to our growing knowledge of Sargassum blooms, 52 00:03:02,720 --> 00:03:05,720 further helping researchers decipher this new threat. 53 00:03:07,680 --> 00:03:09,640 ROY: Sargassum in general, I don't think it's 54 00:03:09,640 --> 00:03:13,640 something that we're going to see go away because 55 00:03:13,640 --> 00:03:18,920 that new population is in an area that is perfect for growth. 56 00:03:19,360 --> 00:03:23,920 So the the issue is how we're going to deal with the Sargassum problem, 57 00:03:24,440 --> 00:03:28,600 And that's one of the reasons that satellite remote sensing 58 00:03:28,920 --> 00:03:31,085 could be very beneficial. 59 00:03:31,085 --> 00:03:33,254 VO: Sargassum continues to threaten coastal communities 60 00:03:33,254 --> 00:03:33,280 could be very beneficial VO: Sargassum continues to threaten coastal communities 61 00:03:33,280 --> 00:03:37,200 around the Caribbean, but satellites and instruments can track how and why 62 00:03:37,200 --> 00:03:40,520 these blooms occur, and help us better safeguard coastal 63 00:03:40,520 --> 00:03:43,640 ecosystems, and the communities that rely on them.