Science and Storms: Predicting the Unpredictable
Late last summer, thousands of people joined forces as records were being broken, not at the summer Olympics in Greece, but rather in Florida. Starting in August Floridians banned together as the peninsula became the only state to suffer four major hurricanes in one season since Texas in 1886.
Just a few months later, national focus shifted to the Indian Ocean when a 9.3-magnitude earthquake caused one of the largest tsunamis in recent history, striking several countries, killing hundreds of thousands people, and leaving millions homeless.
After such disasters, it is common to ask of science why such storms occur, how does one track and predict such a storm, and where is the technology that is needed to save lives?
In reality, different areas of research have been looking at such natural phenomena as earthquakes and hurricanes for decades. Such research crosses disciplines and even countries. Researchers become creative, looking to other technology in different fields, like astronomy and physics. Countries piggy-back onto programs, systems, and satellites other nations have to create a new system with different purposes. In short, researchers study not only their area of science, but any other area, technology, or program available to better understand such complex natural phenomena.
Trying to See "Eye-to-Eye" with Hurricanes
Hurricanes Charley, Frances, Ivan, and Jeanne devastated Florida and other southern states in 2004. Two other major hurricanes that remained at sea rounded out the hurricane season with six major hurricanes and fifteen tropical storms.
Hurricane season started late last fall the first storm did not form until early August. While most seasons see storms forming as early as June, the late start brought more destruction than anticipated. Furthermore, the late start just saw a late end. When the tropical storm Otto finally diminished on December 2nd, the Atlantic seaboard at length could breathe and begin the long process of rebuilding.
As the National Hurricane Center followed the paths of these storms, it found that the mapping techniques used last year needed improvements. To help efficiently evacuate areas, they projected storms five days ahead, as opposed to the three-day projections in previous years. However, the technology was not developed enough to anticipate if a storm would skip areas. After Hurricane Charley hit the west coast of Florida, it skipped up the east coast and reemerged, striking Myrtle Beach, South Carolina. Hurricane Ivan acted even more unpredictably when, after hitting Alabama and heading north, a piece of the system returned to the Gulf of Mexico and caused more damage.
In response to this problem, NASA developed technology to look into the center of the system, helping meteorologists forecast changes in a hurricane's intensity and direction. Using the Japan Aerospace Exploration Agency's (JAXA) Tropical Rainfall Measuring Mission (TRMM) satellite, the pictures from the satellite give valuable information about how the storm is put together, providing clues as to whether a sudden change in the direction of winds near the top of the storm may impact the storm's strength or cause it to jump paths.
"With hurricane forecasts, events change quickly, and meteorologists need data as fast as possible," says Jeffrey Halverson, Meteorologist and TRMM Education and Outreach Scientist. "This new process gives them data within three hours from the time the satellite has flown over a tropical cyclone. We hope this new data product will help the community to better assess the structure and intensity of tropical cyclones."
Professional and amateur storm trackers alike can look into the eye of a storm by going to the TRMM website.
This technology may prove very valuable for the 2005 hurricane season, which is already expected to bring great damage to the Atlantic coast. Forecasters at the National Oceanic and Atmospheric Administration are predicting at least seven Atlantic hurricanes this year, with as many as five matching Ivan's destructive force. The season has already started with Hurricanes Dennis and Emily hitting the Caribbean.
If this hurricane season does prove as destructive as the NOAA predicts, the National Hurricane Center is planning on implementing the five-day storm projections again, despite criticism that it creates unnecessary panic. The NHC is certain that the need for an extended outlook combined with new equipment is necessary, even if it causes some to prepare for a storm that may end up not in their path.
"Last year's hurricane season provided a reminder that planning and preparation for a hurricane do make a difference," says Max Mayfield, director of the NOAA NHC. "Residents in hurricane vulnerable areas who had a plan, and took individual responsibility for acting on those plans, faired far better than those who did not," he explains.
Predicting How the Earth Will Move
As nations celebrated the 2004 holiday season and coming New Year, festivals were put on hold as the world turned its eyes onto the Indian Ocean, where countries were rocked with one of the deadliest natural disasters this century. In his room at the Hilton Arcadia resort at Karon Beach, Phuket, Mike Williams was shaken awoke with the 9.3 magnitude earthquake that occurred off the coast of Sumatra. The tsunami wave followed. "The beach umbrellas and sunbeds were like dolls' furniture as they were swept inland," says Williams. "The surge continued, and dozens of cars were swept along the road like floating toys. It was absolute chaos - very scary," describes Williams.
As the waters retreated, exposing more destroyed homes and land, the death toll continued to rise, settling above 225,000 people. Millions more were left homeless. Relief programs arose everywhere, and people tried to help in every way possible.
Developing technology to predict earthquake magnitude and location from the tiny movements that tectonic plates make everyday has long been the subject of research projects. Scientists tend to look at this problem in two ways: tracing a single earthquake's movements from its epicenter on or looking at several earthquakes over long periods of time.
Miaki Ishii and Peter Shearer, scientists at Scripps Institution of Oceanography at UCSD, in collaboration with Heidi Houston and John Vidale at UCLA's Earth and Space Sciences department, developed a new method for imaging how the earth ruptured during the quake. Called "back projection," the method is not unlike those used to find sources of oil and gas and by astronomers to image distant galaxies. In this method, the scientists use the first-arriving seismic waves generated by an earthquake to produce detailed images within 30 minutes of an event. They then trace seismic waves back to their original rupture source.
In the case of the Sumatra-Andaman event, they used the Japanese Hi-Net array, consisting of about 700 high-quality seismometers, as antennae to track the seismic sources. Ishii and his partners obtained a series of rupture points progressing from south to north in the Sumatra-Andaman region. In this method, the scientists use the first-arriving seismic waves generated by an earthquake to produce detailed images within 30 minutes of an event. They then trace seismic waves back to their original rupture source.
"It's similar to some ideas that have been used in the past," says Shearer. He explains, "But as far as we know it's the first time that it has been applied to directly image the rupture of a large earthquake."
Meanwhile, Álvaro Corral, a physicist at the Universitat Autònoma de Barcelona, connected the reoccurrence time of earthquakes to physics systems. The time interval between successive earthquakes is similar to the physical structure of systems when they change phase in the "critical points," as when water vaporizes from liquid to gas. Researchers may be able to develop projections for location and magnitude of future earthquakes by studying past earthquakes.
"If we note the different earthquakes that have taken place in a given zone over a large period of time," says Corral. He also explains that, "We see that they are grouped together, but the most surprising thing is that if we look at a longer period of time, the groups of earthquakes are themselves also grouped in larger clusters. The same happens for any period of time, for earthquakes of any magnitude, wherever they take place in the world. This has a fundamental implication on the type of phenomenon that earthquakes are; rather than being chaotic, as one might think, we can consider them to be critical."
The ability to predict and carefully track tropical storms, hurricanes, earthquakes, and tsunamis becomes more important with increasingly worse storms and destruction. The new technology being developed could help warn residents in danger. Any technology used to save lives reminds everyone how science helps to improve society. Cooperation between countries like Japan and the US to study tropical storms show how simple it can be to develop new processes by joining forces.
What about the parallels found between astronomy, physical science, and earthquakes? Well, that's just plain scientific ingenuity.