The Hurricane Hunters

by Ivan Ray Tannehill

For more than fifty years after this, there were arguments about the reasons for these changes in temperature and humidity. Some scientists claimed that they were caused merely by the heating of the sun in a clear sky and that the air which preceded and followed the center was cooled and saturated by the rain. Some of the Jesuit scientists at Manila did not agree. One weatherman showed, for example, that if they took air at 75° and 100% humidity and heated it to 88°, the humidity would fall only to about 61% and that the air at Manila at that time of year had never had such a low humidity (53%), even when the sun was shining.

The general conclusion was that the air descends in the eye of the tropical storm. At least, they were convinced that it descended in the Manila typhoon. When air descends, it is compressed, coming into lower levels where the pressure is higher. This compression causes its temperature to rise and the air then has a bigger capacity for moisture. In other words, the air becomes warmer and drier. There never has been full agreement on this question. Certainly, in some cases, the air is not warmer and drier in the center.

In later years, typhoon centers passed over other observatories and had various effects. However, one struck Formosa on September 16, 1912, and the calm center passed over the observatory long after the sun had gone down. In this case, the temperature jumped from 75° to 94° and this could not be explained by the direct heat of the sun. But there were different results in other cases and in one instance the temperature fell a little.

All of these observations were confined to ground level and what the observer could see from there or from shipboard, where he was being bounced around by violent seas and sometimes was thoroughly drenched by the mountainous waves breaking over the decks. One example was the Idaho in the typhoon in 1869.

A half-century later, two British destroyers were trapped in the same region by an unheralded typhoon. Setting out for Shanghai in the early morning, they rounded the Shantung Promontory and headed across the Yellow Sea at fifteen knots, with sunlight gleaming on the water ahead. The weather looked favorable, barometer high, wind light, but it failed to stay that way very long. By ten o’clock there was a strong wind on the port beam, blowing gustily from the east, and an ominous rising sea. Reducing speed to eleven knots, the commander of the destroyer in the lead—called the Exe—found by dead reckoning that he was only about eight miles from land and, although he was running almost parallel to the coast, their situation was beginning to look dangerous. He had to make a decision as to his future course.

Among other disturbing factors was the design of the ships. These destroyers were of a new type, with a large forecastle which made it likely that they would drag their anchors if they tried to lie-to in a sheltered place on that exposed coast. The two ships held their course. By noon the visibility had dropped to less than a mile. The commander feared that he would be unable to identify any land he might see through the increasing gloom and concluded that his chances of finding a safe shelter among the rock-bound islands along the coast was fast becoming nil. So he signaled to the other destroyer to head fast for the open sea. In the next hour, the wind and sea mounted rapidly and he was certain that they were being overtaken by the dangerous sector of the typhoon. Now they were in real trouble!

His first lieutenant was the last of his officers out of school, so the commander asked him about the law of storms and the proper course under the circumstances. According to the latest books which the lieutenant had studied, they should have steamed toward the northwest but this would have thrown them onto a lee shore. The commander decided that there was no choice except to hold their course and run the chance of going into the dreaded center of the typhoon. So they got busy, doubly securing all movable gear and seeing that all was snug for a frightening trip into the unknown. The commander was annoyed, not so much by the battering the ship was taking as by the cheerful attitude of the lieutenant, who seemed to be looking forward to this new experience.

In this miserable situation they fought heavy gales and towering seas for hours. The other destroyer had been lost from view but now appeared close on their beam. She assumed strange attitudes in the growing darkness. “At times,” the commander said, “she would be poised on the crest of a great wave, her fore part high above the sea and her keel visible up to the conning tower; the after part, also high in the roaring wind, leaving her propellers racing far out of the water. Then she would take a dive and an intervening wave would blot out this ‘merry picture,’ and then, to our relief as the wave passed, a mast would appear waving on the other side and then we would catch sight of her funnels and finally her hull, still above water.” As darkness closed in, the crew of the Exe were glad they could no longer see the other destroyer for it made them vividly conscious that their own little ship was going through equally dangerous contortions.

During this time the destroyer Exe had suffered much damage. The upper deck had been swept clear. Much water was getting below and the pumps were choked. The commander was weary from holding on to the bridge and trying to keep his balance. The crew was frightened more than ever by the increasing power of the storm and the inexorable approach of the unknown horrors in the center.

The awful night passed in this terrifying manner, with the barometer steadily going lower, and the quartermaster straining to keep the craft on course. With powerful winds full in his face and drenched by spray, he managed to hold the ship most of the time and made the best use of her high bows. When he failed and allowed the ship to get a few points off course, the steep waves threw her on her beam ends and came crashing along the upper decks, making it a tough job to get her back with her nose against the elements, and the high bows as a sort of shield against the brutal sea. Besides, the compass light had been beaten out and in the blackness of the storm he had no way of judging the direction except by the crash of the wind and water in his face.