WEBVTT FILE 1 00:00:01.666 --> 00:00:04.433 [rythmic music begins] Narrator: The White House recently called upon the USDA's 2 00:00:04.433 --> 00:00:08.933 Forest Service and the Bureau of Land Management to produce the first ever 3 00:00:08.933 --> 00:00:12.300 national inventory of mature and old growth forests. 4 00:00:14.600 --> 00:00:17.600 After a year’s work, the first stage is complete, 5 00:00:18.166 --> 00:00:21.683 and thanks to observations from high above, scientists will soon 6 00:00:21.683 --> 00:00:25.766 be able to view, measure and understand our forests like never before. 7 00:00:27.650 --> 00:00:30.983 NASA's GEDI instrument on board the International Space Station 8 00:00:31.366 --> 00:00:34.316 helps estimate tree height and biomass, 9 00:00:34.316 --> 00:00:37.316 adding a new dimension to the study. 10 00:00:38.516 --> 00:00:41.183 Palmer: The Forest Service has been studying 11 00:00:41.183 --> 00:00:44.150 old growth forests going back almost 100 years. 12 00:00:44.150 --> 00:00:47.150 Others before us have been studying in much longer. 13 00:00:47.783 --> 00:00:50.783 Many of these forests have been managed 14 00:00:50.900 --> 00:00:56.016 for millennia by native peoples who have deep connections to these forests. 15 00:00:56.100 --> 00:00:59.100 But we still have a tremendous amount to learn. 16 00:00:59.633 --> 00:01:02.933 We have data that's been measured on the ground 17 00:01:02.933 --> 00:01:05.866 that tells us a tremendous amount about what's out there. 18 00:01:05.866 --> 00:01:10.133 But a ground inventory is necessarily going to have gaps in it. 19 00:01:10.316 --> 00:01:14.300 We can measure one plot for every 6000 acres of forest. 20 00:01:14.633 --> 00:01:19.433 What remote sensing data does is it really allows us 21 00:01:19.433 --> 00:01:23.633 to fill in those spatial gaps, but also the temporal gaps. 22 00:01:24.466 --> 00:01:27.800 We know that with the frequency of disturbances 23 00:01:27.800 --> 00:01:32.300 that are happening on our landscape now, we need more rapid information. 24 00:01:33.000 --> 00:01:37.650 So, for example, with the NASA GEDI sensor that we're using in this 25 00:01:37.816 --> 00:01:41.416 particular study, we're working with the NASA scientists 26 00:01:41.416 --> 00:01:45.316 to identify that relationship with those ground-measured 27 00:01:45.316 --> 00:01:48.316 information we know about forests. 28 00:01:48.800 --> 00:01:52.200 Narrator: Ground surveys collect detailed information about forest types 29 00:01:52.200 --> 00:01:55.966 and health, and tree ring data, provide a window back in time. 30 00:01:56.566 --> 00:01:58.100 Pederson: Today, we're in a 31 00:01:59.266 --> 00:02:02.266 marginally documented old growth forest. 32 00:02:03.116 --> 00:02:07.616 It's on Forest Service land in the Tionesta National Forest. 33 00:02:08.216 --> 00:02:12.383 And this is home to the oldest documented eastern hemlock. 34 00:02:13.283 --> 00:02:17.400 And we're putting in plot today and then going to try to core 35 00:02:17.400 --> 00:02:20.400 some more older trees so we can get about five to 36 00:02:20.483 --> 00:02:23.483 maybe six centuries of history. 37 00:02:23.966 --> 00:02:27.183 Looks like it's got a density of rings and a release. 38 00:02:28.616 --> 00:02:31.350 Old growth forests are quite often where we go 39 00:02:31.350 --> 00:02:34.516 to get those long histories where we can learn about 40 00:02:35.550 --> 00:02:39.016 frost events and droughts and insect outbreaks 41 00:02:39.016 --> 00:02:43.516 and any kind of important ecological, climatological, and even sometimes 42 00:02:43.516 --> 00:02:48.383 cultural events that happen, they’re stored in the trunks of these trees. 43 00:02:48.750 --> 00:02:52.216 And the oldest trees have the best stories because they can go farther 44 00:02:52.216 --> 00:02:52.950 back in time. 45 00:02:54.416 --> 00:02:55.200 Narrator: These living 46 00:02:55.200 --> 00:02:59.700 time capsules and their ecosystems help clean our air and drinking water 47 00:02:59.933 --> 00:03:02.966 and provide spaces for recreation and wildlife. 48 00:03:04.166 --> 00:03:07.733 They also help absorb more than 10% of our annual greenhouse 49 00:03:07.733 --> 00:03:12.350 gas emissions. While younger vegetation accumulates carbon more rapidly, 50 00:03:12.833 --> 00:03:16.950 old growth forests contain more biomass overall and store more carbon, 51 00:03:17.333 --> 00:03:20.333 another variable that can be estimated from space. 52 00:03:20.900 --> 00:03:25.050 In addition to GEDI, observations from NASA's ICESat-2 satellite 53 00:03:25.250 --> 00:03:29.266 and several field campaigns, have helped measure our ever changing forests. 54 00:03:30.383 --> 00:03:32.216 Pederson: You know the precision of lidar 55 00:03:32.216 --> 00:03:36.833 now from a space station, how you can beam the lidar 56 00:03:36.833 --> 00:03:40.750 system down and in 30 meter radius plots. 57 00:03:40.766 --> 00:03:45.166 you can pull in all this information about the height of the canopy, 58 00:03:45.466 --> 00:03:49.283 the changes in the canopy over space, and density of the forest. 59 00:03:49.850 --> 00:03:52.316 The precision of these beams now from outer space 60 00:03:52.316 --> 00:03:55.666 to get detailed information about a forest 61 00:03:55.666 --> 00:03:57.450 is truly astounding. 62 00:03:58.666 --> 00:04:01.700 These ecosystems are so complex. 63 00:04:01.700 --> 00:04:04.350 From the treetop to the bedrock. Right? 64 00:04:04.350 --> 00:04:09.350 We're still learning so much about what's underground, what's in the soil, 65 00:04:09.350 --> 00:04:13.200 this live dynamic system and what we can't see. 66 00:04:13.400 --> 00:04:18.600 The old growth forests have a function of time that as a human, we can't fathom. 67 00:04:18.883 --> 00:04:23.300 From a Western science perspective, we do not understand. 68 00:04:23.366 --> 00:04:27.833 And it wouldn't be wise to lose these systems.