1 00:00:00,000 --> 00:00:03,909 [Music] 2 00:00:09,030 --> 00:00:06,789 this is rain and snow 3 00:00:11,509 --> 00:00:09,040 not just a day 4 00:00:13,990 --> 00:00:11,519 or even a year 5 00:00:19,990 --> 00:00:14,000 this is the culmination of almost 20 6 00:00:23,910 --> 00:00:21,750 led by the global precipitation 7 00:00:25,429 --> 00:00:23,920 measurement mission the newest version 8 00:00:27,509 --> 00:00:25,439 of the nasa product called the 9 00:00:28,950 --> 00:00:27,519 integrated multi-satellite retrievals 10 00:00:32,229 --> 00:00:28,960 for gpm 11 00:00:35,350 --> 00:00:32,239 or imerg analysis has remastered almost 12 00:00:37,670 --> 00:00:35,360 20 years of rain and snow creating a 13 00:00:40,229 --> 00:00:37,680 crisper clearer and more complete 14 00:00:42,150 --> 00:00:40,239 picture than ever before 15 00:00:44,310 --> 00:00:42,160 this marks a major milestone in the 16 00:00:46,950 --> 00:00:44,320 effort to generate a long-term record of 17 00:00:49,670 --> 00:00:46,960 global precipitation 18 00:00:51,830 --> 00:00:49,680 with this two-decade long record you can 19 00:00:54,549 --> 00:00:51,840 see regional and global patterns in 20 00:00:58,150 --> 00:00:54,559 unprecedented detail 21 00:01:04,630 --> 00:01:01,590 over india and southeast asia massive 22 00:01:06,870 --> 00:01:04,640 monsoon rains shift 23 00:01:08,789 --> 00:01:06,880 storm tracks march along in higher 24 00:01:11,590 --> 00:01:08,799 latitudes 25 00:01:13,270 --> 00:01:11,600 the seas bubble in the southern ocean 26 00:01:15,990 --> 00:01:13,280 which scientists consider one of our 27 00:01:17,910 --> 00:01:16,000 planet's last great unknowns 28 00:01:20,550 --> 00:01:17,920 if we look a little closer we can see 29 00:01:23,270 --> 00:01:20,560 the wettest and driest places on earth 30 00:01:26,710 --> 00:01:23,280 extreme high events tend to be very 31 00:01:28,630 --> 00:01:26,720 concentrated very localized whereas the 32 00:01:31,109 --> 00:01:28,640 opposite what we would call droughts 33 00:01:33,109 --> 00:01:31,119 tend to be very widespread and sort of 34 00:01:35,749 --> 00:01:33,119 diffuse looking the wettest places on 35 00:01:37,830 --> 00:01:35,759 the globe occur over oceans particularly 36 00:01:40,149 --> 00:01:37,840 in places where the surrounding land 37 00:01:42,550 --> 00:01:40,159 forces air into a converging pattern 38 00:01:45,030 --> 00:01:42,560 over warm waters that provide a lot of 39 00:01:46,310 --> 00:01:45,040 evaporation 40 00:01:49,270 --> 00:01:46,320 for example 41 00:01:51,590 --> 00:01:49,280 off the coast of indonesia 42 00:01:53,109 --> 00:01:51,600 as well as off the northwest coast of 43 00:01:56,069 --> 00:01:53,119 colombia 44 00:01:57,830 --> 00:01:56,079 and just 2 000 miles to the south is one 45 00:02:00,469 --> 00:01:57,840 of the driest areas 46 00:02:02,310 --> 00:02:00,479 the atacama desert in chile 47 00:02:04,389 --> 00:02:02,320 across the atlantic 48 00:02:05,910 --> 00:02:04,399 namibia experiences some of the least 49 00:02:08,469 --> 00:02:05,920 rain as well 50 00:02:10,070 --> 00:02:08,479 the interesting thing of the last two is 51 00:02:11,830 --> 00:02:10,080 that they're right next to the ocean 52 00:02:13,670 --> 00:02:11,840 they're next to cold ocean and so in 53 00:02:15,110 --> 00:02:13,680 fact those dry zones actually extend 54 00:02:17,270 --> 00:02:15,120 over the ocean 55 00:02:19,589 --> 00:02:17,280 we tend not to think of ocean deserts 56 00:02:22,949 --> 00:02:19,599 but in fact that's what's going on 57 00:02:24,869 --> 00:02:22,959 over the past two decades precipitation 58 00:02:26,869 --> 00:02:24,879 has been changing 59 00:02:28,790 --> 00:02:26,879 what we're seeing isn't a change in the 60 00:02:30,630 --> 00:02:28,800 overall amount of rainfall 61 00:02:31,990 --> 00:02:30,640 but rather how that rainfall is 62 00:02:34,150 --> 00:02:32,000 distributed 63 00:02:36,470 --> 00:02:34,160 what seems to be happening and this is 64 00:02:39,110 --> 00:02:36,480 still subject to some interpretation 65 00:02:41,509 --> 00:02:39,120 is that the regions that get more 66 00:02:43,350 --> 00:02:41,519 precipitation are getting even more and 67 00:02:45,670 --> 00:02:43,360 the areas that get less precipitation 68 00:02:47,509 --> 00:02:45,680 are getting even less you perhaps heard 69 00:02:48,949 --> 00:02:47,519 the phrase the wet get wetter and the 70 00:02:51,030 --> 00:02:48,959 dry get drier 71 00:02:53,509 --> 00:02:51,040 this long record allows researchers to 72 00:02:55,589 --> 00:02:53,519 better test climate models by comparing 73 00:02:57,910 --> 00:02:55,599 the model's virtual scenario with 74 00:03:00,070 --> 00:02:57,920 decades of real precipitation 75 00:03:02,790 --> 00:03:00,080 we're able to go back in time and 76 00:03:05,589 --> 00:03:02,800 re-analyze large-scale events like el 77 00:03:07,830 --> 00:03:05,599 nino by making these revised estimates 78 00:03:10,070 --> 00:03:07,840 in the past it gives us better insight 79 00:03:12,710 --> 00:03:10,080 into the behavior of the atmosphere and 80 00:03:15,110 --> 00:03:12,720 it allows people who are doing say model 81 00:03:16,869 --> 00:03:15,120 verification to do a more accurate job 82 00:03:18,470 --> 00:03:16,879 of verifying their models for that 83 00:03:20,309 --> 00:03:18,480 particular event which happened in the 84 00:03:21,430 --> 00:03:20,319 past than they could have done at the 85 00:03:23,350 --> 00:03:21,440 time 86 00:03:25,350 --> 00:03:23,360 improving the models with the past will 87 00:03:26,869 --> 00:03:25,360 help predict the future 88 00:03:28,149 --> 00:03:26,879 and that doesn't stop with weather 89 00:03:30,309 --> 00:03:28,159 forecasts 90 00:03:33,430 --> 00:03:30,319 a long precipitation record is a vital 91 00:03:35,270 --> 00:03:33,440 tool for researchers modeling floods and 92 00:03:37,110 --> 00:03:35,280 landslides 93 00:03:39,750 --> 00:03:37,120 disease outbreaks 94 00:03:43,270 --> 00:03:39,760 agricultural forecasts 95 00:03:45,190 --> 00:03:43,280 tracking our main source of fresh water 96 00:03:48,390 --> 00:03:45,200 all of these applications need lots of 97 00:03:50,229 --> 00:03:48,400 data over many decades to fine-tune 98 00:03:52,789 --> 00:03:50,239 these statistics and models that 99 00:03:54,430 --> 00:03:52,799 agencies rely upon for making decisions