1 00:00:00,433 --> 00:00:03,436 Think about a big old oak tree sitting in the middle of a field. 2 00:00:03,737 --> 00:00:08,575 That tree has been there for 100 years, and it has gone through droughts 3 00:00:09,009 --> 00:00:12,245 and rain and snow and cold and heat, 4 00:00:12,912 --> 00:00:15,915 and it is adjusting constantly to that environment. 5 00:00:16,383 --> 00:00:18,852 So it makes those adjustments 6 00:00:18,852 --> 00:00:21,855 biochemically in their leaves. 7 00:00:22,255 --> 00:00:25,592 You know, it's really easy to think of plants as being, like, almost inert. 8 00:00:25,925 --> 00:00:27,494 I mean, they just sort of sit there. 9 00:00:27,494 --> 00:00:31,197 But the fact is, these plants are constantly making adjustments. 10 00:00:32,632 --> 00:00:35,935 What you're looking at are leaves all over the globe, 11 00:00:35,935 --> 00:00:39,005 changing color for one full year. 12 00:00:39,506 --> 00:00:42,475 This is the first time we've been able to see vegetation 13 00:00:42,475 --> 00:00:46,212 from space in three plant pigments all at once. 14 00:00:46,579 --> 00:00:50,016 For decades we've been able to look at measurements of chlorophyll, 15 00:00:50,083 --> 00:00:53,186 the green pigment in plants that we're all familiar with. 16 00:00:53,887 --> 00:00:56,723 But it's looking at all the plants as kind of one whole, 17 00:00:56,723 --> 00:00:59,325 because most all of them have chlorophyll. 18 00:00:59,893 --> 00:01:02,896 With PACE, we can see more colors. 19 00:01:02,896 --> 00:01:05,698 More colors means being able to sense more pigments. 20 00:01:06,699 --> 00:01:08,068 Pigments are substances 21 00:01:08,068 --> 00:01:11,371 that absorb and reflect light and aid in photosynthesis. 22 00:01:11,971 --> 00:01:15,575 Now, in addition to detecting chlorophyll, PACE can detect 23 00:01:15,575 --> 00:01:19,646 other leaf pigments as well, like carotenoids and anthocyanins. 24 00:01:19,913 --> 00:01:23,249 Carotenoids are pigments that give us the reds, oranges and yellows. 25 00:01:23,483 --> 00:01:25,051 They're always present in leaves, 26 00:01:25,051 --> 00:01:28,054 but they really show up when chlorophyll breaks down. 27 00:01:28,588 --> 00:01:31,357 Anthocyanins are the reds and purples that appear due 28 00:01:31,357 --> 00:01:34,360 to temperature, stress, and bright light conditions. 29 00:01:34,828 --> 00:01:40,100 The leaves are designed to be solar panels, and they absorb a lot of light. 30 00:01:40,233 --> 00:01:44,637 But the problem that they have is if they don't have the nutrients 31 00:01:44,637 --> 00:01:49,776 or the water available to them to be able to photosynthesize successfully, 32 00:01:50,477 --> 00:01:53,480 the fact that they're absorbing sunlight could actually damage them. 33 00:01:53,646 --> 00:01:57,283 And so they have these other pigments that they use to help 34 00:01:57,617 --> 00:01:59,085 mitigate that damage 35 00:01:59,085 --> 00:02:00,687 and protect the leaves. 36 00:02:00,820 --> 00:02:02,555 These pigments then 37 00:02:02,555 --> 00:02:06,860 are signals to us that the leaves are stressed in one way or another. 38 00:02:08,394 --> 00:02:11,397 We can start to see these kinds of signals all over the globe, 39 00:02:11,464 --> 00:02:15,401 potentially pointing scientists to areas for further investigation. 40 00:02:16,369 --> 00:02:19,172 The data allows us to see large-scale farmland 41 00:02:19,172 --> 00:02:22,175 behaving differently than the surrounding landscape. 42 00:02:22,775 --> 00:02:27,413 Here, in the U.S. Midwest, the blues indicate relatively high carotenoids, 43 00:02:27,981 --> 00:02:31,017 suggesting stress responses of corn to a heat wave 44 00:02:31,017 --> 00:02:32,986 in August 2024. 45 00:02:34,287 --> 00:02:38,324 In Siberia, one of the coldest places on Earth, we can see larches-- 46 00:02:38,324 --> 00:02:42,428 deciduous conifers-- adapt to survive the long, cold winter. 47 00:02:43,429 --> 00:02:46,666 As autumn approaches, chlorophyll disappears in larches 48 00:02:46,699 --> 00:02:50,003 as carotenoids increase, seen in the shades of blue, 49 00:02:50,003 --> 00:02:53,006 and eventually lose their needles altogether. 50 00:02:53,540 --> 00:02:56,509 In the South American Pantanal, we see a region 51 00:02:56,509 --> 00:02:59,512 very different from the year-round green Amazon. 52 00:03:00,446 --> 00:03:03,316 The Pantanal is the world's largest tropical wetland 53 00:03:03,316 --> 00:03:05,852 and largest flooded grassland, 54 00:03:05,852 --> 00:03:09,455 and its seasonality is largely driven by precipitation patterns. 55 00:03:10,623 --> 00:03:11,491 The dry season 56 00:03:11,491 --> 00:03:14,928 shows us a shift from greens to reds as chlorophyll is lost. 57 00:03:15,528 --> 00:03:18,531 The greens return with the wet season in September. 58 00:03:20,066 --> 00:03:21,701 PACE continues to collect data 59 00:03:21,701 --> 00:03:23,336 on how plant pigments shift, 60 00:03:23,570 --> 00:03:25,705 providing an opportunity for researchers 61 00:03:25,705 --> 00:03:27,707 to study land changes in a new way. 62 00:03:28,575 --> 00:03:31,311 The kind of people that would use this would be foresters 63 00:03:31,311 --> 00:03:34,581 to look at forested areas that are perhaps being affected 64 00:03:34,581 --> 00:03:37,784 by insect damage or drought stress. 65 00:03:38,218 --> 00:03:42,655 We will be able to look at how the plants, how the vegetation, changes after large 66 00:03:42,655 --> 00:03:47,927 disasters, like really large fires or perhaps a large storm event. 67 00:03:48,428 --> 00:03:51,664 These responses that the plants are making, 68 00:03:51,798 --> 00:03:56,402 come in early, and so we'll be able to see them 69 00:03:56,402 --> 00:04:00,306 before you actually start to see leaves drop off and things like that. 70 00:05:07,507 --> 00:05:09,008 the water loss. 71 00:05:09,008 --> 00:05:11,744 And so we can look at this water use efficiency. 72 00:05:11,744 --> 00:05:15,481 And that tells us something about how much water is being drawn 73 00:05:15,481 --> 00:05:19,218 out of the soil by the plants and sent into the atmosphere, 74 00:05:19,485 --> 00:05:23,056 which then affects how much water flow is going into streams. 75 00:05:23,556 --> 00:05:26,626 And so from that we can build up the whole hydrology. 76 00:05:27,026 --> 00:05:31,497 And so this is a key piece of describing the hydrology for regions and such. 77 00:05:31,531 --> 00:05:35,335 I mean, just this is so much connect connection. 78 00:05:35,335 --> 00:05:36,869 You know. 79 00:05:36,869 --> 00:05:37,770 Yeah. 80 00:05:37,770 --> 00:05:39,639 Between all these different, spheres.