Spotting the Furious Typhoon
BY “AWAKE!” CORRESPONDENT IN HAWAII
“TYPHOON!” The word strikes terror into the hearts of Chinese, Japanese, Filipinos, Guamanians and Micronesians. It is a word of Chinese origin used west of the 180th meridian to describe a storm that attains a wind speed of seventy-five miles per hour or greater. East of that imaginary north-south dividing line such storms are called hurricanes.
Every year dozens of these howling windstorms sweep through the area of the Pacific and Indian Oceans. On occasion typhoons veer over mainland China, causing great destruction of life and property. At times, Japan is battered by two typhoons at one time, with floods and landslides causing great loss of life.
Huge mounts of energy are released during a typhoon, or hurricane. “It is estimated,” notes the Encyclopaedia Britannica (1974 edition), “that a mature hurricane may export more than 3,500,000,000 tons of air per hour.”
How do these massive storms get their start? What is it like to live through one? Can they be spotted far enough in advance to enable persons to escape their destructive fury?
Have you ever heard of the “intertropical convergence zone”? Known also by its initial letters ITCZ, this is a belt of converging trade winds and rising air that encircles the earth near the equator. This zone is a seedbed of tropical storms, for here the sun’s heat warms up air and water more than in any other area on earth. With what effect?
Water from the ocean’s surface continually evaporates and rises with the warm air to form clouds. When conditions are right, several updrafts of warm air may combine, producing a chimney effect. As the chimney continues to grow, it will start spinning due to the rotation of the earth. Air pressure at the chimney’s bottom drops rapidly, drawing in still more air and moisture from outside the rotating column. It is similar to when water is sucked in at the bottom of a sipping straw. The warm, humid air may rise to a height of thirty to thirty-five thousand feet, where it encounters a blanket of cold air. Then it spreads out; the moisture condenses and begins falling as rain, whirling faster and faster with the winds as the storm develops.
Water in the “eye” of such a storm may be ten to fifteen feet higher than the surrounding ocean. A severe typhoon or hurricane may churn up ocean waves to a height of some fifty to a hundred feet. Can you imagine the destructive force of such huge billows? The fury of winds at typhoon or hurricane force has been known to drive small splinters through large trees, carry huge ships ashore, and wreck trains.
As an example of a typhoon’s fury, on October 7, 1737, storm-tossed waves some forty feet high smashed into Calcutta, India, killing 300,000 persons. On Monday, August 16, 1971, typhoon Rose pelted the island of Hong Kong with rain and winds up to 120 miles per hour. The ferocious storm peppered Hong Kong’s rocky beaches with some forty oceangoing vessels that were torn from their anchorages. Concerning hurricane Fifi, which swept across Nicaragua, Honduras, El Salvador, Guatemala and Belize last September, an article in Readers Digest reported:
“Fifi saved her worst malevolence for Choloma and other towns on both sides of the Merendón Sierra. A slow-moving hurricane may dump five to ten inches of rain on flat country. It can pour five times that much on a mountainous area. In Choloma, Manuel Becerra’s Texaco station sits a few feet higher than the surrounding land. ‘As the water rose, people began coming from the low-lying areas,’ he said. ‘By midnight at least 800 people were huddled around the station.’
“Then the deluge began. ‘In even a hard rain you can see individual drops,’ he said. ‘But suddenly a solid curtain of water poured from the sky.’
“The downpour continued for four hours. The saturated earth on the steep Merendón could hold no more. Suddenly, thousands of tons of earth, rocks and trees slid downhill. In Ocotillo, Arcadio Gámez heard the roar. He rushed outside, firing his pistol into the air to alert other residents. About 40 followed him higher up the mountain. In shock they watched every house in the village hurled into the ravine. ‘It looked as if the mountain were floating,’ said Gámez. Thirty-one luckless people from Ocotillo were swept down the corridor of death in a churning mélange of earth, houses, boulders, cattle and huge trees.”
Before Fifi’s fury subsided, the hurricane claimed the lives of some 7,000 to 8,000 persons and left hundreds of thousands homeless in resultant floods and landslides. In the town of Choloma, mentioned above, 2,700 of its 5,000 inhabitants were reported dead.
Is there a way to avoid such terrible consequences? Can hurricanes and typhoons be spotted far enough in advance to make for large-scale preservation of life?
Detecting the Birth of a Storm
Due to poor communications facilities, in years gone by a rapidly falling barometer indicating a swift drop in air pressure was about all the advance warning that people would get. However, this often happened too late for them to escape a storm’s fury. Later, with the spread of radio communications, volunteer observers in the island chains were able to provide a few hours of advance warning that a storm was in the making.
Then came radar with its capacity to detect a typhoon’s spiraling cloud formation. However, since radar signals travel in a straight line, whereas the earth curves, radar detection of typhoons is possible only when the storm comes within about two hundred miles of a radar instrument.
By far the most helpful means for spotting typhoons are weather satellites. One of them, which circles the earth in a north-south direction, scans an area of 2,000 by 2,000 miles every four and a half minutes. What the satellite “sees” is recorded on magnetic tape for readout at two command stations in the United States, one at Fairbanks, Alaska, and the other at Wallops Island, Virginia.
The facilities of this satellite enable weather stations at Guam, Wake Island, Honolulu and many other locations to know about atmospheric conditions for hundreds of miles around them. Forecast offices at Honolulu and Guam evaluate the cloud pictures received and check for any cloud patterns typical of a tropical storm or typhoon.
Another weather satellite has its orbital speed set so as to remain in a fixed position at a Pacific equatorial point. This enables weather stations to receive photographic coverage of most of the Pacific basin every twenty-two minutes. A similar satellite serves over the Atlantic Ocean.
When a Typhoon Is Imminent
What happens when a typhoon pattern appears on a weather-satellite picture? At such a time weather stations throughout the area are alerted. Steps are taken for the preservation of life and, to the extent possible, to minimize damage to property. But that is not all.
Weather stations send aloft large balloons with transmitting equipment. Special receivers track these instruments, which provide information about temperature, humidity, wind speed and direction all the way from the surface of the storm to an altitude of about seventeen miles. Besides this, special typhoon hunter planes are dispatched from Guam or the Philippines to track a storm in progress and to radio back information about wind speeds at various locations from the edge of the storm to its very center, as well as sea conditions. An eyewitness reports what it is like to ride in such a plane:
“It was as dark as midnight. In the never-ceasing turbulence our 120,000 lb. airplane was bounced around like a cork in a rapid . . . Imagine if you can, a cubicle about the size of an ordinary bathroom, along with two tons of electronic gear, thermos bottles, rescue equipment and the crew, and then stir it all well.”
Spotting and tracking typhoons right from their birth is of the utmost importance. For example, the coral-atoll type of islands, where many Micronesians live, are especially vulnerable to storm waves, for these islands are, on the average, no higher than twenty feet above sea level. Ships at sea, too, appreciate storm warnings that allow sufficient time to get out of harm’s way.
Indeed, much progress has been made in providing advance warnings of furious typhoons or hurricanes. Unfortunately, though, many lives are lost due to such warnings being ignored. In view of the destructive forces unleashed by such howling tropical windstorms, it is wise to flee from their path as quickly as possible.