Meteorology: The Storm Killers

Like a ballerina bereft of her balance, Hurricane Arlene whirled on a curious course through the Atlantic to open the 1963 storm season. Her wild dance subsided to a gale-force pirouette, then suddenly spun back to hurricane size at week’s end. Though she finally seemed headed out to sea, Arlene’s sisters* may even now be waiting in the wings. But when they begin their destructive spin toward the U.S. East Coast, they will be met by a group of storm-killing scientists who hope to learn how to stop them.

Bombing Esther. After the wide spread hurricane havoc of 1954 and 1955, the U.S. Weather Bureau began an intensive program aimed at learning how to slow a hurricane down and make it change course. Observations from air planes and balloons showed large quantities of supercooled water high above each hurricane’s heat chimney — the rising column of moist, warm, low-pressure air near the storm’s calm eye. Meteorologists speculated that if this water could be turned to ice, the energy released in the process might change the chimney’s pressure enough to calm the raging winds.

In 1961 the Weather Bureau sent a strike force of airplanes on a “bombing” mission aimed at Hurricane Esther’s heat chimney. Into the chimney they dropped eight finned, 130 lb. bombs which spewed a cloud of minute silver iodide particles as they fell. The crystals acted like small ice “seeds,” and supercooled droplets of water instantly froze around them. Instant icing released the latent heat of fusion, equivalent to the energy of eight 20-kiloton atomic bombs. In one hour, radar showed that a 160° segment of the chimney had been knocked out. Maximum wind speeds dropped by as much as 14% in the seeded sector. But two hours after seeding stopped, Esther had repaired the damage.

Waiting for Beulah. Encouraged by the results, the Weather Bureau last year joined forces with the Navy in Project Stormfury, an experiment to determine if large-scale, continuous seeding could kill a hurricane early in its career. But for all its grand plans, Stormfury’s experimental attack is highly restricted by the fear that something may go wrong. In 1947 the Navy seeded a hurricane far out in the Atlantic, then watched in embarrassed amazement as the storm turned abruptly and careened in a devastating swath through Savannah, Ga. Though no one could prove that seeding caused the course change, fear of lawsuits has limited Stormfury targets to hurricanes at least 48 hours away from shore—nearly 1,000 miles at the hurricane’s average speed of 20 miles per hour. “Bureaucrats are scaredy-cats,” growls one Stormfury scientist. Beyond such limitations, the storm killers want a hurricane that is moving toward the coast and not fluctuating as erratically as Arlene.

Last week Stormfury Project Director Dr. Robert Simpson, 50, eagerly prepared for a shot at Hurricane Beulah —provided she meets all the requirements when she appears. His eleven airplanes and 50 men stood by at Roosevelt Roads Naval Station in Puerto Rico, armed with more than ten times as much silver iodide as was “smoked” into Esther two years ago. Their work will only be a check on the 1961 experiment, not a full-scale attempt to kill a hurricane, but that day is coming. And when it does, Simpson will get a particular pleasure out of the experiment. In 1919, when he was seven years old, a hurricane ripped through his home town of Corpus Christi. As the water rose 16 ft. above street level, he swam to the roof of the courthouse. Perched high and wet over the scene of devastation, he swore revenge. He still intends to get it.

*The U.S. Weather Bureau list for 1963 reads: Beulah, Cindy, Debra, Edith, Flora, Ginny, Helena, Irene, Janice, Kristy, Laura, Margo, Nona, Orchid, Portia, Rachel, Sandra, Terese, Verna, Wallis.