1 00:00:01,920 --> 00:00:06,600 Speaker 1: Welcome to brain Stuff. Production of I Heart Radio, Hey 2 00:00:06,680 --> 00:00:10,479 Speaker 1: brain Stuff Lauren vog obamb here. In recent years, climate 3 00:00:10,560 --> 00:00:13,040 Speaker 1: change has loomed like a dark specter over the globe, 4 00:00:13,280 --> 00:00:17,040 Speaker 1: contributing to everything from gentrification in Miami is high income 5 00:00:17,079 --> 00:00:20,080 Speaker 1: coastal dwellers seek new residents fur their inland away from flooding, 6 00:00:20,360 --> 00:00:24,239 Speaker 1: two refugees fleeing drought and crop shortages in Guatemala. But 7 00:00:24,360 --> 00:00:27,880 Speaker 1: the urgency around the issue reached new heights in the 8 00:00:27,960 --> 00:00:32,800 Speaker 1: United Nations. Intergovernmental Panel on Climate Change or IPCC stated 9 00:00:32,840 --> 00:00:36,600 Speaker 1: that rapid, quote, far reaching and unprecedented changes in all 10 00:00:36,680 --> 00:00:39,560 Speaker 1: aspects of society would be needed in order to drop 11 00:00:39,720 --> 00:00:45,360 Speaker 1: carbon dioxide levels by and prevent catastrophic global warming. Scientists 12 00:00:45,440 --> 00:00:48,320 Speaker 1: have indeed proposed drastic measures, just not the way that 13 00:00:48,360 --> 00:00:51,320 Speaker 1: you might think. In the same i p c C report, 14 00:00:51,600 --> 00:00:54,320 Speaker 1: the u N suggested that adding two point five billion 15 00:00:54,360 --> 00:00:57,080 Speaker 1: acres that's one billion hectares of forest to the world 16 00:00:57,240 --> 00:00:59,600 Speaker 1: could help limit global warming in future decades to just 17 00:00:59,640 --> 00:01:03,000 Speaker 1: two and seven degrees fahrenheit that's one point five degrees celsius, 18 00:01:03,040 --> 00:01:05,000 Speaker 1: which would stave off some of the worst effects of 19 00:01:05,000 --> 00:01:08,480 Speaker 1: climate change. And now the U N might just have 20 00:01:08,600 --> 00:01:11,840 Speaker 1: the data to back up their proposal. In another study 21 00:01:11,920 --> 00:01:14,760 Speaker 1: unveiled in July of twenty nineteen and the publication Science, 22 00:01:15,040 --> 00:01:17,560 Speaker 1: a group of researchers associated with the Crowther Lab in 23 00:01:17,600 --> 00:01:20,520 Speaker 1: Switzerland found that global tree restoration to the tune of 24 00:01:20,600 --> 00:01:23,560 Speaker 1: nine hundred million acres that's point nine billion hectares of 25 00:01:23,600 --> 00:01:26,280 Speaker 1: canopy cover, an area that's approximately the size of the 26 00:01:26,360 --> 00:01:30,720 Speaker 1: United States is quote our most effective climate change solution 27 00:01:30,800 --> 00:01:34,840 Speaker 1: to date. That would require upwards of half a trillion trees. 28 00:01:35,720 --> 00:01:38,720 Speaker 1: These trees would store two hundred and five billion tons 29 00:01:38,760 --> 00:01:41,040 Speaker 1: of carbon, or roughly two thirds of the carbon that's 30 00:01:41,040 --> 00:01:44,760 Speaker 1: been omitted by we humans since the Industrial Revolution. Some 31 00:01:44,880 --> 00:01:47,480 Speaker 1: news reports said that this much forest restoration is the 32 00:01:47,480 --> 00:01:50,720 Speaker 1: equivalent of roughly one trillion trees, but that statistick is 33 00:01:50,760 --> 00:01:55,520 Speaker 1: from an estimate in a report from but we spoke 34 00:01:55,520 --> 00:01:59,320 Speaker 1: with the current studies lead author Jean Frascois Bastin via email. 35 00:01:59,760 --> 00:02:02,720 Speaker 1: He said the idea was to estimate what tree cover 36 00:02:02,840 --> 00:02:06,200 Speaker 1: could be expected when you removed the human factor, i e. 37 00:02:06,480 --> 00:02:09,320 Speaker 1: What specific types of forest would naturally occur in the 38 00:02:09,360 --> 00:02:13,720 Speaker 1: absence of other development and where. The team used the 39 00:02:13,760 --> 00:02:16,720 Speaker 1: form of artificial intelligence known as machine learning to build 40 00:02:16,840 --> 00:02:20,440 Speaker 1: quote a model to link tree cover with climate, soil 41 00:02:20,520 --> 00:02:24,119 Speaker 1: and topography based on seventy eight thousand observations of tree 42 00:02:24,120 --> 00:02:28,640 Speaker 1: cover in protected areas. The researchers then projected the data 43 00:02:28,680 --> 00:02:31,480 Speaker 1: further to estimate the potential total tree cover of the 44 00:02:31,520 --> 00:02:35,640 Speaker 1: whole planet if human civilization didn't exist. But of course 45 00:02:35,720 --> 00:02:39,200 Speaker 1: humans do exist, so the team then excluded land currently 46 00:02:39,200 --> 00:02:42,880 Speaker 1: being used for urban settlements, crop lands, and existing forests, 47 00:02:43,160 --> 00:02:46,239 Speaker 1: which yielded the total amount of land available for restoration. 48 00:02:47,160 --> 00:02:49,760 Speaker 1: The study offers a map showing how much tree coverage 49 00:02:49,800 --> 00:02:52,320 Speaker 1: different parts of the globe might support, the top three 50 00:02:52,360 --> 00:02:57,080 Speaker 1: areas being Russia, Canada, and the United States. The studies 51 00:02:57,080 --> 00:03:00,400 Speaker 1: timing a lines of current global efforts around ecological rest ration. 52 00:03:00,960 --> 00:03:04,120 Speaker 1: A one example is the Trillion Trees Vision, which seeks 53 00:03:04,120 --> 00:03:07,679 Speaker 1: to restore one trillion trees by fifty Another is the 54 00:03:07,720 --> 00:03:10,520 Speaker 1: Bone Challenge, which is a partnership between the Government of 55 00:03:10,520 --> 00:03:13,680 Speaker 1: Germany and the u n's International Union for Conservation of 56 00:03:13,760 --> 00:03:17,320 Speaker 1: Nature that aims to restore three seventy one million acres 57 00:03:17,360 --> 00:03:21,160 Speaker 1: of deep forested land by which is about of the 58 00:03:21,200 --> 00:03:26,000 Speaker 1: current studies recommendation. You might be thinking, well, that sounds 59 00:03:26,040 --> 00:03:28,440 Speaker 1: pretty easy. Let's all roll up our sleeves and save 60 00:03:28,480 --> 00:03:31,079 Speaker 1: the planet by planting one tree at a time, right, 61 00:03:31,880 --> 00:03:34,639 Speaker 1: But some experts say the situation is actually a little 62 00:03:34,680 --> 00:03:38,680 Speaker 1: more complicated than that rosy picture, especially if most nations 63 00:03:38,680 --> 00:03:42,800 Speaker 1: don't chip into help. Although by fifty eight nations had 64 00:03:42,800 --> 00:03:45,280 Speaker 1: banded together to commit an acreage that would exceed the 65 00:03:45,320 --> 00:03:48,360 Speaker 1: BONB Challenge goal, most of the restoration work to date 66 00:03:48,360 --> 00:03:52,240 Speaker 1: has been done by only a few countries. We also 67 00:03:52,240 --> 00:03:54,680 Speaker 1: spoke with Jim Hallett, chair of the Board of Directors 68 00:03:54,680 --> 00:03:58,440 Speaker 1: for the Society of Ecological Restoration. He cited major challenges 69 00:03:58,480 --> 00:04:03,560 Speaker 1: to implementing restoration on such a global scale, quote including financing, governance, 70 00:04:03,640 --> 00:04:06,480 Speaker 1: land tenure and ownership, and capacity to do the work. 71 00:04:06,920 --> 00:04:10,200 Speaker 1: There's ample evidence that in some contexts, if the benefits 72 00:04:10,240 --> 00:04:13,080 Speaker 1: of restoration are not equally shared, the project will fail. 73 00:04:13,560 --> 00:04:17,920 Speaker 1: So incentive programs have to be carefully developed, and restorational 74 00:04:17,960 --> 00:04:20,720 Speaker 1: loan will likely not be enough. It takes time, after 75 00:04:20,760 --> 00:04:23,719 Speaker 1: all to implement such a big restoration projects, and also 76 00:04:23,760 --> 00:04:26,599 Speaker 1: for these trees to store carbon, and how it stresses 77 00:04:26,640 --> 00:04:29,560 Speaker 1: that we have to not just restore previously forested lands, 78 00:04:29,720 --> 00:04:34,280 Speaker 1: but preserve what we've currently got. Other scientists question not 79 00:04:34,320 --> 00:04:36,840 Speaker 1: only the practicality of the studies claims, but also the 80 00:04:36,839 --> 00:04:41,400 Speaker 1: studies very methodology. But we spoke with Ica Liling, climate 81 00:04:41,440 --> 00:04:44,760 Speaker 1: change researcher and professor of horticultural sciences at the University 82 00:04:44,760 --> 00:04:47,520 Speaker 1: of Bonne. He pointed out that some of the areas 83 00:04:47,520 --> 00:04:50,680 Speaker 1: marked for restoration couldn't support more trees than they already do. 84 00:04:51,200 --> 00:04:54,640 Speaker 1: Some of them are in permafrost regions for example. Also 85 00:04:54,880 --> 00:04:58,919 Speaker 1: quote the methodology implicitly, probably not on purpose, implies that 86 00:04:59,000 --> 00:05:03,120 Speaker 1: carbon stock is portional to canopy cover i e. Ecosystems 87 00:05:03,160 --> 00:05:06,480 Speaker 1: without trees contain no carbon. This is clearly false and 88 00:05:06,520 --> 00:05:11,880 Speaker 1: strongly inflates the global estimate of restoration. Young Barner, Leedling's 89 00:05:11,920 --> 00:05:14,680 Speaker 1: colleague and a professor for economics of sustainable land use 90 00:05:14,720 --> 00:05:18,839 Speaker 1: at the University of Bonne, is similarly skeptical. Barner says 91 00:05:18,880 --> 00:05:21,320 Speaker 1: that some of the areas being proposed for restoration under 92 00:05:21,320 --> 00:05:24,040 Speaker 1: the current study are already in use for other purposes. 93 00:05:24,760 --> 00:05:28,600 Speaker 1: Barner considers the study to be a quote interesting academic exercise, 94 00:05:28,960 --> 00:05:32,200 Speaker 1: but as a climate change mitigation strategy proposal, and it 95 00:05:32,320 --> 00:05:35,560 Speaker 1: is being advertised as such, it sends a misleading signal 96 00:05:35,640 --> 00:05:40,680 Speaker 1: to the international climate policy debate, but don't fret. Both 97 00:05:40,720 --> 00:05:43,680 Speaker 1: Bustine and Hallett emphasize that the u N has declared 98 00:05:45,000 --> 00:05:48,800 Speaker 1: thirty the Decade on Ecosystem restoration, which could spur nations 99 00:05:48,800 --> 00:05:51,880 Speaker 1: to act quickly, and some countries are already tackling the 100 00:05:51,880 --> 00:05:56,400 Speaker 1: initiative head on. And according to Hallett, forest restoration boasts 101 00:05:56,400 --> 00:05:59,960 Speaker 1: far more perks than just impacting climate change, including maintaining 102 00:06:00,160 --> 00:06:03,760 Speaker 1: or even increasing bio diversity and preserving the ecosystem that 103 00:06:03,760 --> 00:06:07,359 Speaker 1: we humans rely upon for our food and water. But 104 00:06:07,520 --> 00:06:09,800 Speaker 1: even the studies authors acknowledge that it's going to take 105 00:06:09,839 --> 00:06:12,400 Speaker 1: a lot of goodwill to make this grand vision of reality. 106 00:06:13,279 --> 00:06:17,159 Speaker 1: Bastine said, what we need is a universal action. International 107 00:06:17,200 --> 00:06:21,240 Speaker 1: agencies and geo's governments all citizens anyone can be involved. 108 00:06:21,640 --> 00:06:25,520 Speaker 1: Local communities and small organizations may be especially effective. While 109 00:06:25,560 --> 00:06:28,080 Speaker 1: they do not have the same reach as national agencies, 110 00:06:28,160 --> 00:06:30,080 Speaker 1: they have the benefit of knowing what works best in 111 00:06:30,120 --> 00:06:38,040 Speaker 1: their own backyards. Today's episode was written by Terry our 112 00:06:38,120 --> 00:06:40,840 Speaker 1: Lagata and produced by Tyler Clang. 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