1 00:00:09,510 --> 00:00:10,290 ~Sound of Helicopter and music in background~ 2 00:00:10,290 --> 00:00:15,880 Peder Nelson: My land cover career really started in 2002… 3 00:00:15,880 --> 00:00:18,040 …with the biggest wildfire in Oregon’s history. 4 00:00:18,040 --> 00:00:20,000 And that was the Biscuit Wildfire. 5 00:00:20,000 --> 00:00:23,000 I at the time was doing botany surveys. 6 00:00:23,000 --> 00:00:29,850 And looking for rare plants or rare mushrooms. And so I was spending a lot of time out on 7 00:00:29,850 --> 00:00:36,020 On the forest, looking at and taking photos and doing the documentation that a scientist or a land manager does. 8 00:00:36,020 --> 00:00:39,470 When that fire happened, it changed everything. 9 00:00:39,470 --> 00:00:46,860 Because we all had to react to this fire that was burning up some of the places that I had literally been the day before. 10 00:00:46,860 --> 00:00:50,430 And it was mapping what was there, and what was under threat. 11 00:00:50,430 --> 00:00:57,160 But it was also mapping the effects of the fire. We needed to find a way to look across five-hundred thousand acres. 12 00:00:57,160 --> 00:01:00,740 And the only way that we could really do that was satellite data. 13 00:01:00,740 --> 00:01:05,970 If we can’t get out and actually measure every single thing, what are we missing? 14 00:01:05,970 --> 00:01:11,940 And that’s where citizen scientist can actually come in and really help traditional scientists. To better understand 15 00:01:11,940 --> 00:01:17,420 What is happening around them. But also fill in these gaps. 16 00:01:17,420 --> 00:01:20,000 ~♪Music♪~ 17 00:01:20,000 --> 00:01:25,380 Title: Why Observe? Land Cover 18 00:01:25,380 --> 00:01:30,280 Narrator: The Global Learning and Observations to Benefit the Environment Program 19 00:01:30,280 --> 00:01:33,150 Is an international science and education program. 20 00:01:33,150 --> 00:01:39,920 It provides students and the public with the opportunity to participate in data collection and the scientific process. 21 00:01:39,920 --> 00:01:45,440 The GLOBE Observer App, is one of the opportunities allowing citizen scientists and students to take land cover 22 00:01:45,440 --> 00:01:51,090 Observations around the world and submit them to a larger database. 23 00:01:51,090 --> 00:01:54,570 But, what exactly is land cover? 24 00:01:54,570 --> 00:01:58,380 Doctor Eric Brown de Colstoun of NASA’s Goddard Space Flight Center explains 25 00:01:58,380 --> 00:02:04,750 Eric: Land cover is really the basic form of the landscape that we have around us. 26 00:02:04,750 --> 00:02:12,540 So, whether it’s forest or a desert. But it’s really one of the components of the landscape that we can study from space. 27 00:02:12,540 --> 00:02:16,800 Narrator: Peder Nelson is a scientist who uses land cover imagery in his research. 28 00:02:16,800 --> 00:02:23,180 Peder: I am a remote sensing scientist, who studies land cover across the globe. 29 00:02:23,180 --> 00:02:31,010 I use satellite imagery to make maps of land cover. And try to quantify what covers the earth. 30 00:02:31,010 --> 00:02:38,110 Sometimes a satellite can’t see what’s happening underneath a tree canopy, or what’s happening underneath cloud cover. 31 00:02:38,110 --> 00:02:45,580 And so we really need people to go out there to take these photos and do these observations, to help fill in where a satellite can’t 32 00:02:45,580 --> 00:02:47,660 actually make some observations. 33 00:02:47,660 --> 00:02:49,590 Narrator: Just like any digital photograph 34 00:02:49,590 --> 00:02:53,730 Land cover images are made up of a series of pixels. To show what covers the Earth. 35 00:02:53,730 --> 00:02:57,900 A pixel, or picture element, is the smallest unit of a digital image. 36 00:02:57,900 --> 00:03:02,730 When combined with thousands of other pixels, a picture is formed. 37 00:03:02,730 --> 00:03:06,180 Each pixel color shown represents a land cover type. 38 00:03:06,180 --> 00:03:11,230 It’s from these pixels where ground verification, or ground-truthing, come into play. 39 00:03:11,230 --> 00:03:14,500 You see, depending on what satellite is taking images 40 00:03:14,500 --> 00:03:20,030 A pixel can cover roughly an area of thirty to five-hundred meters squared. 41 00:03:20,030 --> 00:03:26,650 For imagery captured by Landsat, a pixel is thirty meters squared. Or about the size of a baseball diamond. 42 00:03:26,650 --> 00:03:34,460 However, part of that pixel showing forest, might actually be water. Or shrubs. 43 00:03:34,460 --> 00:03:41,400 By taking land cover observations, citizen scientists can help answer these questions when it comes to land cover maps. 44 00:03:41,400 --> 00:03:47,040 Sooo, why are these land cover observations so important? 45 00:03:47,040 --> 00:03:51,080 Why are they taken in the first place? 46 00:03:51,080 --> 00:03:55,150 Eric: We also are looking at how these components are changing over time. 47 00:03:55,150 --> 00:04:01,220 So, deforestation in the Amazon or across the world. How are cities expanding? 48 00:04:01,220 --> 00:04:06,970 A lot of different things to study and really the view from space is the way we do it here at NASA. 49 00:04:06,970 --> 00:04:14,850 We have big supercomputers that simulate the physics of the atmosphere and the land. The interaction between the Earth’s 50 00:04:14,850 --> 00:04:16,190 Systems. 51 00:04:16,190 --> 00:04:23,580 It’s important to have that land cover map. It sets certain parameters. 52 00:04:23,580 --> 00:04:28,870 Those models can actually be used to look at current day conditions and weather. 53 00:04:28,870 --> 00:04:36,750 So based on these current conditions, what might the Earth look like fifty or a hundred years from now. 54 00:04:36,750 --> 00:04:46,620 There’s an element of understanding but then also being able to predict into the future, you know, what that might be like. 55 00:04:46,620 --> 00:04:49,710 What these changes may mean for us. 56 00:04:49,710 --> 00:04:54,580 Narrator: Each point shown here represents a real world measurement of environmental conditions. 57 00:04:54,580 --> 00:04:59,440 Scientists use computer models to fill in information where measurements may not exist. 58 00:04:59,440 --> 00:05:07,640 By verifying the satellite imagery and using the data for these models, scientists can predict changes in our environment more accurately. 59 00:05:07,640 --> 00:05:14,990 One of these scientists using land cover maps to track urbanization as part of her work is Doctor Amita Mehta of NASA’s Goddard Space Flight Center. 60 00:05:14,990 --> 00:05:20,940 Amita: So, urbanization changes terrain as well as characteristics of the surface itself. 61 00:05:20,940 --> 00:05:27,080 And so, impervious surfaces is what we look at when we are monitoring flooding. 62 00:05:27,080 --> 00:05:34,180 When there are, say, parking lots, cement and concrete surfaces increase. So previously, if it was farmland 63 00:05:34,180 --> 00:05:45,190 Or something which was not built, and if that is built now. That water previously that could go or percolate in the soil and in the ground 64 00:05:45,190 --> 00:05:48,620 now cannot go in and it stays there. 65 00:05:48,620 --> 00:05:51,600 Monitoring helps you to plan for it. 66 00:05:51,600 --> 00:05:59,490 If you see land cover changing, even then you know that how water’s going to flow in that region might change. 67 00:05:59,490 --> 00:06:07,630 If you have to send rescue out or you have to plan for relief activities, and if you know land cover, then you know 68 00:06:07,630 --> 00:06:11,180 Where there might be help needed. 69 00:06:11,180 --> 00:06:22,060 By using land cover maps and models that reflect changes over time, scientists can predict where flooding and other events may occur. 70 00:06:22,060 --> 00:06:29,100 With a changing climate, these predictions from models and land cover maps can help scientists better understand these changes. 71 00:06:29,100 --> 00:06:32,290 And help communities prepare for them. 72 00:06:32,290 --> 00:06:37,700 But, perhaps a more important reason as to why take land cover observations is 73 00:06:37,700 --> 00:06:43,960 You get to participate in a community of scientists, citizen scientists and students. 74 00:06:43,960 --> 00:06:50,580 Eric: So, it’s a very important component that the citizen science and students of the GLOBE Program and GLOBE Observer 75 00:06:50,580 --> 00:06:59,220 Can contribute to is by really giving us the information on the ground of what they’re seeing around them and in front of them. 76 00:06:59,220 --> 00:07:03,680 And we hope over time as well as how maybe some of these things are changing. 77 00:07:03,680 --> 00:07:07,060 Because those would be very valuable for science. 78 00:07:07,060 --> 00:07:12,480 Peder: I saw the value of having information before a hazard happens. 79 00:07:12,480 --> 00:07:18,090 Because once that fire went through an area, we can never recreate that data. 80 00:07:18,090 --> 00:07:24,570 This is all important for us to share and put together because that’s how we understand Earth as a system. 81 00:07:24,570 --> 00:07:34,080 All of these things end up affecting where we live, why we live where we do and why we make some of the choices that we do. 82 00:07:34,080 --> 00:07:39,230 Narrator: To learn more about GLOBE Observer, check out the website at observer.globe.gov 83 00:07:39,230 --> 00:07:40,928 And download the app to start taking your own observations today.