1 00:00:01,020 --> 00:00:04,870 Two days before Hurricane Maria devastated Puerto Rico 2 00:00:04,890 --> 00:00:09,070 a NASA satellite captured a 3-D view of the storm 3 00:00:09,090 --> 00:00:14,750 revealing the processes inside the hurricane that would fuel the storm’s intensification. 4 00:00:14,770 --> 00:00:18,980 NASA’s precipitation satellite has an advanced radar 5 00:00:19,000 --> 00:00:23,410 that measures both liquid and frozen water inside hurricanes. 6 00:00:23,430 --> 00:00:29,590 This satellite is called the Global Precipitation Measurement Core Observatory, or GPM. 7 00:00:29,610 --> 00:00:37,180 Now, for the first time, we can take you inside a hurricane in a 360-degree view of this data. 8 00:00:37,200 --> 00:00:41,560 You can look around by moving your device or clicking and dragging on the screen. 9 00:00:41,580 --> 00:00:48,790 We’re currently inside Hurricane Maria when it was a Category 1 hurricane in September 2017. 10 00:00:48,810 --> 00:00:53,660 This was a few days before it rapidly intensified to a Category 5 hurricane. 11 00:00:53,680 --> 00:00:59,660 Look down and you'll see a map showing where we are inside Hurricane Maria 12 00:00:59,680 --> 00:01:01,540 and what the colors are showing. 13 00:01:01,560 --> 00:01:04,160 The dots around you show areas of rainfall, 14 00:01:04,180 --> 00:01:09,120 where green and yellow show low rates and red and purple show high rates. 15 00:01:09,140 --> 00:01:15,900 The colored areas below the dots show how much rain makes it to the surface. 16 00:01:15,920 --> 00:01:22,910 Look up and you’ll see blue and purple dots that show light and intense frozen precipitation. 17 00:01:22,930 --> 00:01:27,000 Right now we are traveling through a gap between rainbands. 18 00:01:27,020 --> 00:01:31,260 Now we’ll collapse the clouds of dots into the actual data values, 19 00:01:31,280 --> 00:01:37,630 which are in millimeters of precipitation per hour. 20 00:01:37,650 --> 00:01:42,440 The rates in this storm vary from less than 0.5 millimeters per hour 21 00:01:42,460 --> 00:01:47,740 to over 150 millimeters per hour. 22 00:01:47,760 --> 00:01:57,580 It’s these actual values that scientists use to figure out what’s going on inside hurricanes. 23 00:01:57,600 --> 00:02:01,130 Next we’ll turn the numbers into a representation 24 00:02:01,150 --> 00:02:07,170 that helps us to see other 3-D structures in the distance. 25 00:02:07,190 --> 00:02:12,090 Wider, red and purple ellipsoids show higher rainfall rates 26 00:02:12,110 --> 00:02:16,200 and spherical green and yellow ellipsoids show lower rainfall rates. 27 00:02:16,220 --> 00:02:24,780 Rising to 5 kilometers, you’ll see a distinctive change to frozen precipitation, shown in blues and purples. 28 00:02:24,800 --> 00:02:29,660 This transition is the melting layer where falling snow and ice 29 00:02:29,680 --> 00:02:32,740 warm to the point that they melt into water drops. 30 00:02:32,760 --> 00:02:37,510 We are currently moving up a tall column of intense precipitation. 31 00:02:37,530 --> 00:02:39,980 Scientists call these hot towers. 32 00:02:40,000 --> 00:02:44,650 Lots of heat and energy are released in hot towers 33 00:02:44,670 --> 00:02:48,800 as rising water vapor condenses into precipitation. 34 00:02:48,820 --> 00:02:52,670 Most hot towers are between 10 and 15 kilometers high 35 00:02:52,690 --> 00:02:55,980 - roughly the altitude that commercial jets fly. 36 00:02:56,000 --> 00:03:00,640 Multiple hot towers are common in intensifying hurricanes. 37 00:03:00,660 --> 00:03:07,450 Here’s another hot tower that’s about 17 kilometers tall. 38 00:03:07,470 --> 00:03:09,660 Hot towers often appear near the eyewall, 39 00:03:09,680 --> 00:03:14,260 a ring of heavy wind and rainfall surrounding the center of the storm. 40 00:03:14,280 --> 00:03:19,060 We’re now in the eye of Hurricane Maria. 41 00:03:19,080 --> 00:03:23,980 At this stage of development, Maria’s eyewall is asymmetrical 42 00:03:24,000 --> 00:03:28,160 with heavier rain in the northern part colored in purple. 43 00:03:28,180 --> 00:03:31,580 This is common in storms impacted by environmental winds. 44 00:03:31,600 --> 00:03:42,520 A few days after this time, Maria’s eyewall intensified and became more symmetrical. 45 00:03:42,540 --> 00:03:48,010 While NASA's GPM satellite can detect big features like the shape of the eyewall, 46 00:03:48,030 --> 00:03:51,770 it can also measure tiny precipitation particles. 47 00:03:51,790 --> 00:03:58,390 These blue drops show the size and density of ice and water particles inside Hurricane Maria, 48 00:03:58,410 --> 00:04:02,490 which is also known as the drop size distribution. 49 00:04:02,510 --> 00:04:08,480 Big drops are colored in dark blue and small drops in light blue and white. 50 00:04:08,500 --> 00:04:14,150 Looking at drop sizes and rainfall rates provides a key part of the equation 51 00:04:14,170 --> 00:04:17,530 in understanding hurricane intensity. 52 00:04:17,550 --> 00:04:22,870 Factors such as temperature, humidity, wind speed, and clouds 53 00:04:22,890 --> 00:04:26,540 influence the size of the precipitation particles, 54 00:04:26,560 --> 00:04:31,000 which in turn affects how much rain falls and how a storm grows. 55 00:04:31,020 --> 00:04:36,700 These advanced satellite measurements are critical for improving forecasts 56 00:04:36,720 --> 00:04:41,370 of how these powerful storms may intensify and where they may go. 57 00:04:41,390 --> 00:04:45,960 Scientists are seeing things never measured before, 58 00:04:45,980 --> 00:04:50,290 revealing new insights into hurricanes -- drop by drop. 59 00:04:50,310 --> 00:05:02,247