Lesson: Hurricanes and Hot Towers Global Precipitation Measurement Mission Developed by Kristen Weaver GPM Master Teacher NASA Goddard Space Flight Center

Guiding Questions Storms: Have you ever experiences a hurricane or a severe storm? What was it like? Hurricane Damage: What are some of the effects of hurricanes? Hurricane Causes: What conditions cause hurricanes to form? Predicting the Path: How do we predict the path of a hurricane? How have those predictions changed over time, especially with the use of satellites? Using Satellites: How can satellites look inside a hurricane? Predicting the Intensity: What can “hot towers” in a hurricane tell us about its intensity? This slide could be shown to students as a preview of the lesson, or used solely as a reference for the teacher.

Engage Have you ever experienced a hurricane or a severe storm? What was it like? Use these questions as a way to start a discussion to get at students background knowledge and prior experiences, so that they have a context for the lesson. The pictures will appear when you click, especially useful if students are having trouble coming up with ideas. Images from Microsoft Office ClipArt

Winds and Storm Surge Somerset Point in Pinopolis, SC along the shores of Lake Moultrie during Hurricane Gaston on August 29, 2004 North Roosevelt Boulevard, Key West, Florida during Hurricane Wilma, October 2005 Image courtesy of Mike Stafford, http://www.erh.noaa.gov/chs/pictures.shtml Image source: http://www.srh.noaa.gov/key/?n=wilma

Before and After In the top image, taken in 1998, notice the pier, pier house, and the antebellum house. The bottom image shows the same location on August 31, 2005, two days after Hurricane Katrina made landfall. This photo shows the complete destruction of these landmarks. (Image and text from http://coastal.er.usgs.gov/hurricanes/katrina/photo-comparisons/mainmississippi.html)

Effects of a Hurricane 9th Ward flooding caused by Hurricane Katrina Damage caused by Hurricane Katrina Images from: http://sos.noaa.gov/Education/forecast.html

What causes hurricanes? Video link: http://oceantoday.noaa.gov/fuelforthestorm/ (length 2:19)

Three Factors of Hurricane Formation What do hurricanes need to be able form? Warm water (at least 80°) Moist Air Converging Winds Image source: http://scijinks.jpl.nasa.gov/hurricane

Where do hurricanes form? The storms get what they need from the warm equatorial waters off the coast of Africa, and then blow west toward the U.S. coast.

Hurricane Damage Because hurricanes can be so damaging, we want to be able to predict when and where they will hit land and how strong they might be, to help people prepare. Storm surge from Hurricane Ike Damage caused by Hurricane Gustav Image source: http://sos.noaa.gov/Education/forecast.html

Prediction the Path of a Hurricane We especially need to know the path of the hurricane to warn people who might be affected. Image source: http://www.nws.noaa.gov/om/hurricane/pdfs/HurricanesUNF07.pdf, page 17 When advisories are being issued, these products can be found at http://www.nhc.noaa.gov/ (National Hurricane Center, from the National Weather Service). Click the image to go to a website showing any current hurricane warnings. Tropical Storm Force Wind Speed probabilities, 120 hour, for Hurricane Katrina issued 5 PM Wednesday, August 24, 2005/NOAA

Track Forecast Cones A track forecast cone represents the probable track of a tropical cyclone (called a hurricane when they form in the Atlantic Ocean). These are changed as scientists get new data about the storm, because they want to be as accurate as possible. Image source: http://www.nhc.noaa.gov/archive/2005/KATRINA_graphics.shtml (shows an animation of the progression of the prediction cones for Hurricane Katrina, click on the image to go to animation) Click the image to go an animation of the progression of forecast cones for the storm.

Historical Predictions Back in the old days, hurricane predictions were based entirely on ground observations. Before radio, telephones, and the Internet, imagine how hard it would be to share information, and warn people they might be in danger! The great Galveston hurricane (in 1900) roared through the prosperous island city with winds in excess of 130 miles per hour and a 15-foot storm surge. When it was finally over, at least 3,500 homes and buildings were destroyed and more than 8,000 people were killed. Click the image to go to http://celebrating200years.noaa.gov/magazine/galv_hurricane/welcome.html for more information about the Great Galveston Hurricane of 1900. Image and caption source: http://celebrating200years.noaa.gov/magazine/galv_hurricane/Galveston19001.html

Developments in Prediction Technology Later, ships at sea were able to transmit information to shore via radio, and we developed radar and hurricane hunter aircraft (as in NASA’s HS3 mission) to give us more data to put into computer models to help with predictions. Image sources: http://www.nssl.noaa.gov/tools/radar/, http://www.srh.noaa.gov/lch/?n=Humberto, http://www.nasa.gov/mission_pages/hurricanes/missions/hs3/ Click on the image of the radar tower or radar data to go to a brief description of NOAA’s radar research, link: http://www.youtube.com/watch?v=hUm83vk8smo (length 0:39) Click on the image of the plane to go to an animation of a NASA’s Global Hawk aircraft scanning a storm to monitor eyewall development, link: http://www.youtube.com/watch?v=5VODtQCx8Fc (length 0:40) Click on either image to go to a short video about NOAA’s advances in radar.. Click the image to go to an animation of the aircraft scanning a storm to monitor the formation of the eyewall.

Modern Predictions Even better, these days we have satellites that can watch the storm the entire time its active, greatly improving our ability to predict the path of a hurricane. Hurricane Bonnie, August 1998: 5-Day Forecasts vs. Actual Storm Track. Improved forecasts can save money ($600K to $1M per mile of coast evacuated) and lives by more precisely predicting where the hurricane eye will be located at landfall. Source. Dr. A. Hou, NASA DAO Image and caption source: http://www.nasa.gov/pdf/62317main_ICS_Clouds.pdf, page 23 Clicking the image will link to a video about forecasting, leading into the coming discussion about forecasting the intensification of hurricanes. Video link: http://youtu.be/MmEdgKjf7Hs (length 2:09) Click the image to go to a video about forecasting hurricanes.

Satellite Views of Hurricanes Satellites can show us the storm clouds as they move across the ocean, such as in this animation of Hurricane Katrina Link to video: http://scijinks.jpl.nasa.gov/hurricane-Katrina (length 1:00) But what if we want to see more, such as how much rain is falling, or what is happening inside the storm? Satellites can help us with that, too.

Tracking Precipitation from Space Satellites can provide a more complete picture of rain from space, allowing scientists to look at storms, rainfall totals, and changes throughout days to years The Tropical Rainfall Measuring Mission (TRMM) has been providing rainfall data since 1998 in the tropics and mid latitudes The Global Precipitation Measurement (GPM) Mission will extend observations of rain and snow up to the Arctic and Antarctic Circles Image source (and for more information about TRMM): http://trmm.gsfc.nasa.gov/overview_dir/background.html

Instruments on TRMM - Microwave NASA scientists are using the TRMM satellite to understand which parts of a hurricane produce rainfall and why, like this microwave image of a hurricane. The red and yellow indicate areas of heavier rainfall compared to the blue and green. This is especially useful over oceans, where we don’t have rain gauges.

Instruments on TRMM - Radar Using radar, TRMM can even see inside a storm! Revealing the 3-D structure of the hurricane can tell us a lot about what will happen next with the storm. Hurricane Sandy on Oct. 28, two days prior to landfall Link for animation: http://www.youtube.com/watch?v=0_2pcVIJvBM. (length 0:10) Click the image to go to an animation of the data.

Instruments on TRMM The upper image shows the same 3-D view into Hurricane Sandy (using radar) as the previous slide. The lower image is microwave data showing rainfall totals, also for Sandy. The more data we have to work with, the better chance we have of making good predictions! This slide shows how the instruments on TRMM can work together to give us data about a storm.

Hot Towers Looking at what are called “hot towers” using radar has helped scientists develop insight into what causes hurricanes to intensify – the towers often occur before a storm gets stronger. Pretty important if you’re in the path of one! Clicking on the image should link directly to an animation looking inside Hurricane Bonnie (length 0:52). If it doesn’t work, other formats are available at http://svs.gsfc.nasa.gov/goto?1150. Thanks to Dr. Scott Braun, TRMM Project Scientist and Dr. Dalia Kirschbaum, GPM Applications Scientist and Education & Public Outreach Lead, both at NASA Goddard Space Flight Center for help with the information on the previous slides about TRMM’s instruments. TRMM Observations of Hurricane Bonnie (1998)

Towers in the Tempest Link to video: http://gpm.nasa.gov/education/videos/towers-tempest (length 4:20) Video Description:  'Towers in the Tempest' is a 4.5 minute narrated animation that explains recent scientific insights into how hurricanes intensify. This intensification can be caused by a phenomenon called a 'hot tower'. For the first time, research meteorologists have run complex simulations using a very fine temporal resolution of 3 minutes. Combining this simulation data with satellite observations enables detailed study of 'hot towers'. The science of 'hot towers' is described using: observed hurricane data from a satellite, descriptive illustrations, and volumetric visualizations of simulation data. The first section of the animation shows actual data from Hurricane Bonnie observed by NASA's Tropical Rainfall Measuring Mission (TRMM) spacecraft. Three dimensional precipitation radardata reveal a strong 'hot tower' in Hurricane Bonnie's internal structure. The second section uses illustrations to show the dynamics of a hurricane and the formation of 'hot towers'. 'Hot towers' are formed as air spirals inward towards the eye and is forced rapidly upwards, accelerating the movement of energy into high altitude clouds. The third section shows these processes using volumetric cloud, wind, and vorticity data from a supercomputer simulation of Hurricane Bonnie. Vertical wind speed data highlights a 'hot tower'. Arrows representing the wind field move rapidly up into the 'hot tower, boosting the energy and intensifying the hurricane. Combining satellite observations with super-computer simulations provides a powerful tool for studying Earth's complex systems. 

Share what you’ve learned! Now that you know the basics about what causes a hurricane and how and why we try to predict them, create a news report or weather forecast (performed with a script or created as a comic strip), telling people about a hurricane that’s coming and how we know where it will hit and if it will intensify. If you wish to have students also talk about hurricane preparedness, “Hurricanes…Unleashing Nature’s Fury” (http://www.nws.noaa.gov/om/hurricane/pdfs/HurricanesUNF07.pdf) is a great resource. Images from Microsoft Office ClipArt

News Report or Comic Strip Some ideas to consider including: How is hurricane forecasting different now than it used to be? Imagine being a weather forecaster in two different areas of the coast, one in the direct path of the hurricane and one only near it. What would be different about what you tell people about the storm? How does our knowledge of a storm change as it gets closer? How might that change what you need to tell people? Optional: How should people prepare for a hurricane?

Extension Activities Extension Activities

“Hurricane Survival” Video Video link: http://oceantoday.noaa.gov/hurricanesurvival/ (length 3:08) A video with dramatic scenes of storms, as well as tips about how to prepare for a hurricane. If you wish your students to include preparedness information in their news report, this is one way for them to get the basics. If you prefer them to have written information to refer to, look at the last few pages of “Hurricanes: Unleashing Nature’s Fury” at http://www.nws.noaa.gov/om/hurricane/pdfs/HurricanesUNF07.pdf or look for other resources at http://www.nhc.noaa.gov/prepare/wwa.php

Comparing Improvements in Predications Image source, and for more information, see: http://www.nhc.noaa.gov/verification/verify5.shtml You can point out to students that there is a clear decrease in the error (measured in nautical miles off the actual track of the hurricane) since 1970. You might also point out how much more variation there is in the lines for predictions further away from landfall (120 hours and 96 hours), but that the data is much tighter for closer-range predictions like 24 hours, showing how much more accurate they are. There is less of an obvious trend in the intensity errors graph, showing how much improvement there is to make in that sort of prediction.

“TRMM at 15: The Reign of Rain” video Link to video: http://gpm.nasa.gov/education/videos/trmm-15-reign-rain (length 3:16) Video Description:  When it rains it pours, goes the saying, and for the last 15 years, the data on tropical rainfall have poured in. NASA's Tropical Rainfall Measuring Mission (TRMM) was launched on Nov. 27, 1997, and for the last decade and a half has enabled precipitation science that has had far reaching applications across the globe. In this video commemorating TRMM's 15th anniversary, Project Scientist Scott Braun looks back at the legacy of the Tropical Rainfall Measuring Mission and a few of the major scientific milestones the satellite has helped achieve.

“Hurricane Storm Surge” video Video link: http://oceantoday.noaa.gov/hurricanestormsurge/ (length 2:35)

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