• Force of nature

    by Cameron Douglas

    telegraph.co.uk CMYKOn November 2 a monster was born near Pohnpei in the Federated States of Micronesia: a broad area of low pressure, destined to become possibly the deadliest typhoon ever to strike the Philippines. Churning westward, the system developed into a tropical depression the following day. On November 4 it was upgraded to tropical storm and given the name Haiyan, a girl’s name meaning “sea swallow.” In the Philippines, it was called Yolanda. One day later the storm had intensified into a typhoon.

    By November 6 the Joint Typhoon Warning Center (JTWC) declared Haiyan a Category 5-equivalent super typhoon. Gathering even more strength, Haiyan took on fearsome proportions. At 1200 hours UTC on November 7 the Japan Meteorological Agency (JMA) clocked its maximum ten-minute sustained wind speed at 235 km/h (145 mph). Six hours later the JTWC reported one-minute sustained winds at 305 km/h, or 196 mph, surpassing the record set by 190-mph Hurricane Camille in 1969.

    The eye of the storm crossed the east edge of the Philippines on November 8. Still gaining speed, the killer ripped across the easternmost provinces; then, with gusts hitting 235 mph, its northern eyewall — the most powerful part of the storm — tore into Cancabato Bay and pushed a two-story-high wall of water into Tacloban City, the densely populated heart of the region, causing terrible loss of life.

    Analysis and history

    What is a typhoon? Such storms are mature tropical cyclones. When these mature cyclones occur in the western region of the North Pacific Ocean, they are called typhoons. In the Northeast and Central Pacific Basin and the North Atlantic, such storms are called hurricanes. In the Southern Hemisphere and the Indian Ocean, they are simply called cyclones.

    Six factors contribute to typhoon formation and development: Warm sea surface temperatures; atmospheric instability; high humidity in the mid to low levels of the troposphere; a pre-existing low-level focus or disturbance; low vertical wind shear; and enough Coriolis force to develop a low pressure center. (Coriolis effect is a property of physics where a force travels in a straight line when viewed from one perspective but rotates when viewed from another. In any low-pressure system, air tends to flow inward but is deflected perpendicular to its velocity by Coriolis force.)

    Most typhoons form from June to November. The most intense tropical cyclones typically occur in the northwestern Pacific. Nearly one-third of all the world’s tropical cyclones happen there, making it the most active basin on Earth. The busiest typhoon season on record for the general western Pacific region was 1964, when 39 tropical storms formed. The slowest was 2010, with 14 storms.

    Typhoons are usually steered west or northwest by the subtropical ridge, which is a significant belt of high pressure located about 30 degrees from the equator. The Philippines usually takes the brunt of landfalls. China and Japan are impacted slightly less, although some of the worst typhoons in history have hit China. The deadliest typhoon of the twentieth century was Typhoon Nina, which struck China in 1975 and killed nearly 100,000 people when 12 reservoirs failed due to flooding. Typhoon records for southern China date back a thousand years.

    Typhoons take one of three general paths:

    • Straight track westward, or straight runner. This affects the Philippines, southern China, Taiwan and Vietnam. Such was the case with Haiyan.
    • A parabolic, recurving track. These affect the eastern Philippines, eastern China, Taiwan, Korea and Japan.
    • Northward track. These move due north from the point of origin, affecting only small islands.

    In rare instances, a hurricane that begins in the eastern or central regions of the Pacific will wander far enough westward to be re-classified as a typhoon.


    The RSMC Tokyo-Typhoon Center, part of the JMA, has been responsible for issuing official typhoon warnings for the western Pacific since 1989. Each National Meteorological and Hydrological Service in the western Pacific is responsible for issuing warnings for specific land areas threatened in their country. Such agencies include the JTWC; the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA); and the Hong Kong Observatory. There are JTWC warning stations in Japan, Honolulu, Hong Kong, and the Philippines.

    Artificial control

    In the 1960’s and ‘70’s the U.S. Government engaged in research to artificially dissipate tropical cyclones. It was called Project Stormfury. Hurricane Debbie was seeded with silver iodide in hopes that supercooled water would freeze in the storm’s outer rainbands and cause the inner eyewall to collapse, thus reducing the winds. Debbie’s wind speed did drop 31 percent, but rebounded after each of two seedings. Previously in 1947, a similar attempt on a hurricane off Jacksonville, Florida resulted in the storm suddenly changing course and plowing head-on into Savannah. Other ideas — towing icebergs into tropical zones, covering the water surface with evaporation inhibitors, throwing dry ice on the cyclone, and even blasting it apart with nuclear weapons — have all suffered the same flaw: the cyclones are simply too large and short-lived to be manipulated by man.

    Climate change

    Climatologists have published studies correlating the intensification of storms with climate change. In a chilling coincidence, the 2013 United Nations Climate Change Conference was underway in Warsaw when Haiyan made landfall in the Philippines. Yeb Saño, the Philippine delegate, announced a hunger strike “in solidarity with my countrymen who are struggling to find food back home.” Sixty people from Climate Action Network also joined the strike.

    To aid victims of Typhoon Haiyan, go to:

    Send comments and suggestions for future Green Pages to: cameron@cedarstreettimes.com/

    posted to Cedar Street Times on November 21, 2013

    Topics: Green


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