News

    Hurricane Prediction More Reliable Than Ever, But Still Imprecise

    Multimedia

    Audio

    The strong hurricanes bearing down on the Caribbean and Gulf of Mexico this year have caused renewed interest in predicting these violent tropical cyclones. Forecasting them has improved significantly in the last 25 years, providing more lead time for evacuation and other protective measures. But, it is still an imprecise science that needs a lot of fine-tuning.

    The giant storms that spin out of the warm waters near the Equator take an enormous toll in death and destruction worldwide each year. The U.S. government's oceans and atmosphere agency NOAA says the number and intensity of hurricanes in the tropical north Atlantic Ocean has risen in the past decade after a 25-year lull. The director of the agency's National Hurricane Center, Max Mayfield, told a U.S. Senate committee that it is as if someone threw a switch in 1995.

    "We've had a lot more hurricanes, not a record number of major hurricanes, but close," he said. "We've had a lot of activity again and the research meteorologists tell us that we are in for another 10 or 20 years or more of this active period here."

    A recent study in the journal Science by a group of U.S. university researchers shows that the annual number of the strongest hurricanes - those with winds higher than 210 kilometers per hour - has almost doubled globally since 1990, from 10 to 18.

    Some scholars blame global warming. They say the heating of the atmosphere by the trapped gasses from burning fossil fuel has caused warmer oceans and more moisture in the air, ideal conditions for tropical cyclones. But Max Mayfield and others say it is premature to make that connection.

    "There are cycles with active periods and inactive periods," he said. "For example, the 1940s, '50s, and '60s were very, very active with lots of hurricanes, lots of major hurricanes, and in the '70s, '80s, and early '90s, the numbers really dropped down. Without invoking global warming, I think that just natural variability alone is what this can be attributed to."

    Whatever the reason for the latest increase in hurricane activity, forecasting them is the key to protecting the population.

    Mr. Mayfield's agency accurately predicted hurricane Katrina's path four to five days before it reached land in late August and devastated a wide swath of the U.S. Gulf of Mexico coast.

    His boss, U.S. oceans and atmosphere agency chief Conrad Lautenbacher, says the prediction saved tens of thousands of lives and contrasts the situation to the loss of hundreds of thousands of lives in December's Indian Ocean tsunami.

    "What makes the difference? Observations," he said. "There was nothing in place in the Indian Ocean to allow observations to be transmitted to an educated and ready-to-act public. In the United States, where we have global observations starting with satellite systems that detect things immediately as they form, ground based systems, air breathing systems, we had four or five days warning time for people to prepare and be ready to move out."

    Sixty or 70 years ago, no advance warnings were possible. Then, in the 1940s, reconnaissance aircraft began hunting such storms regularly. Much later, orbiting satellites started monitoring hurricanes and scientists began putting the data, such as temperature, wind speed, direction and, precipitation into computers to make mathematical models for prediction. Still, just 25 years ago, forecasters could provide only 12 to 18 hours advance notice of an impending hurricane.

    But hurricane Katrina was relatively easy to predict because it stayed on a steady track. Most storms are not so cooperative.

    "Hurricanes by nature are notoriously difficult to predict. They are incredibly fickle beasts," said University of South Alabama meteorologist Keith Blackwell. He told the U.S. Senate committee that, unlike Katrina, many storms are unpredictable four to five days in advance. He argues that three day forecasts are currently the most reliable.

    "We have come a long way with track forecasting of hurricanes, but there still are often severe limits to our skills several days into the future. Much more work remains," he said.

    Mr. Blackwell also says forecasters still have little ability to predict important hurricane conditions such as intensity, size, rainfall amounts, and the tsunami-like surge of ocean water, which is often more devastating than high winds.

    He points out that one of the biggest drawbacks is the lack of data collection inside and immediately around a developing storm.

    University of South Carolina marine biologist Madelyn Fletcher says the density of U.S. coastal weather observations is relatively low compared to those over land. Only 140 sites collect data along the coasts compared to 14,000 on land, and she says that is not enough to make forecasts as reliable as possible.

    "A lot of our weather comes from the ocean," she said. "That emphasizes the great need to have more measurements, more observations, and the serious need for a higher density of observations sites in coastal oceans. I see that in the United States, but I'm sure it is true globally."

    Ms. Fletcher is optimistic that this will improve. She cites the growing network of partnerships among U.S. government forecasters and university researchers to improve coastal weather observations. In addition, the national oceans and atmosphere agency is working with the military and several other government agencies to achieve an integrated ocean observing system, a plan that Washington is seeking to expand with other nations into a global project.

     

     

    This forum has been closed.
    Comments
         
    There are no comments in this forum. Be first and add one

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    Two-thirds of World Faces Water Shortagei
    X
    February 12, 2016 7:31 PM
    Four billion people — or two out of every three on the planet — do not have enough water to meet their basic needs. That is far greater than previously thought, according to a new study that presents a more accurate picture of the problem. As VOA's Rosanne Skirble reports, the findings will help policymakers and the public craft solutions to address the threat.
    Video

    Video Two-thirds of World Faces Water Shortage

    Four billion people — or two out of every three on the planet — do not have enough water to meet their basic needs. That is far greater than previously thought, according to a new study that presents a more accurate picture of the problem. As VOA's Rosanne Skirble reports, the findings will help policymakers and the public craft solutions to address the threat.
    Video

    Video Gateway to Mecca: Historical Old Jeddah

    Local leader Sami Nawar's family has been in the Old City of Jeddah for hundreds of years and takes us on a tour of this ancient route to Mecca, also believed to be the final resting place of Adam's wife, Eve.
    Video

    Video New Technology Aims to Bring Election Transparency to Uganda

    A team of recent graduates from Uganda’s Makerere University has created a mobile application designed to help monitor elections and expose possible rigging. The developers say the app, called E-Poll, will make Uganda's democratic process fairer. From Kampala, VOA's Serginho Roosblad reports.
    Video

    Video As Refugees Perish, Greek Graveyards Fill

    Aid workers on the Greek island of Lesbos say they are struggling to bury the increasing number of bodies of refugees that have been recovered or washed up ashore in recent months.  The graveyards are all full, they say, yet as tens of thousands of people clamor to get out of Syria, it is clear refugees will still be coming in record numbers. For VOA, Hamada Elrasam reports from Lesbos, Greece.
    Video

    Video Russia Bristles at NATO Expansion in E. Europe

    Russian Foreign Minister Sergei Lavrov is meeting Friday with the head of NATO after the Western military alliance and the United States announced plans for the biggest military build-up in Europe since the Cold War. Russia has called NATO's moves a threat to stability in Europe. But NATO says the troop rotations and equipment are aimed at reassuring allies concerned about Russia as VOA's Daniel Schearf reports from Moscow.
    Video

    Video To Fight Zika, Scientists Target Mosquitoes

    Mosquitoes strike again. The Zika virus outbreak is just the latest headline-grabbing epidemic carried by these biting pests, but researchers are fighting back with new ways to control them. VOA's Steve Baragona takes a look.
    Video

    Video Mosul Refugees Talk About Life Under IS

    A top U.S. intelligence official told Congress this week that a planned Iraqi-led operation to re-take the city of Mosul from Islamic State militants is unlikely to take place this year. IS took over the city in June 2014, and for the past year and a half, Mosul residents have been held captive under its rule. VOA's Zana Omar talked to some families who managed to escape. Bronwyn Benito narrates his report.
    Video

    Video Scientists Make Progress Toward Better Diabetes Treatment, Cure

    Scientists at two of the top U.S. universities say they have made significant advances in their quest to find a more efficient treatment for diabetes and eventually a cure. According to the International Diabetes Federation, the disease affects more than 370 million people worldwide. VOA’s George Putic reports.
    Video

    Video NATO to Target Migrant Smugglers

    NATO has announced plans to send warships to the Aegean Sea to target migrant smugglers in the alliance's most direct intervention so far since a wave of people began trying to reach European shores.
    Video

    Video Russia's Catholics, Orthodox Hopeful on Historic Pope-Patriarch Meeting

    Russia's Catholic minority has welcomed an historic first meeting Friday in Cuba between the Pope and the Patriarch of Russia's dominant Orthodox Church. The Orthodox Church split with Rome in 1054 and analysts say politics, both church and state, have been driving the relationship in the centuries since. VOA's Daniel Schearf reports from Moscow.
    Video

    Video Used Books Get a New Life on the Streets of Lagos

    Used booksellers are importing books from abroad and selling them on the streets of Africa's largest city. What‘s popular with readers may surprise you. Chris Stein reports from Lagos.
    Video

    Video After NH Primaries All Eyes on South Carolina

    After Tuesday's primary in New Hampshire, US presidential candidates swiftly turned to the next election coming up in South Carolina. The so-called “first-in-the-South” poll may help further narrow down the field of candidates. Zlatica Hoke reports.
    Video

    Video Smartphone Helps Grow Vegetables

    One day, you may be using your smartphone to grow your vegetables. A Taipei-based company has developed a farm cube — a small, enclosed ecosystem designed to grow plants indoors. The environment inside is automatically adjusted by the cube, but it can also be controlled through an app. VOA's Deborah Block has more on the gardening system.
    Video

    Video Exhibit Turns da Vinci’s Drawings Into Real Objects

    In addition to being a successful artist, Renaissance genius Leonardo da Vinci designed many practical machines, some of which are still in use today, although in different forms. But a number of his projects were never realized — until today. VOA’s George Putic reports.