It is now, in the 21st century, that the concept of weather modification has taken flight. Something unimaginable 100 years ago is now possible and can assist us all in hazard mitigation. What is weather modification? It is an intentional manipulation of the atmosphere to alter the natural process. That is, to bring rain where none was falling or to end rainfall where it continued to fall- or any variation of other weather elements in between. Weather modification has obvious value to those who require a certain weather outcome. For example, while I was stationed in Alaska at Elmendorf AFB as a meteorologist in the late 1970s, it was a routine practice to turn on propane dispensers during episodes of thick cold fog (temperatures below freezing). The local environment was dramatically cooled down. These dispensers were placed near the approach zone of an active runway and, under the right conditions, would successfully raise the visibility from zero to a half mile or greater- just enough to allow aircraft to land. Fog would turn to ice crystals and fall to the ground. It was then, and continues to be today, an excellent form of weather modification that benefits everyone involved. Perhaps the most famous type of weather modification is cloud seeding. This activity has been around since the 1950s with aircraft dropping silver iodide or dry ice into cumulus clouds. There have been mixed results. The theory states that cloud chilling will enhance coagulation of small cloud droplets into larger raindrops. But success is quite dependent upon the right conditions. Skeptics have asserted that some of the apparently successful seeding operations were made into weather systems that would have produced rain anyway. Nonetheless, farmers and ranchers have employed a number of seeding companies in the US, Russia, China and India for decades. There has always been a market, especially during droughts, and continues to be today. A similar concept was utilized on a much grander scale from 1962 through 1983 with Operation Stormfury. In this version of cloud seeding, tropical
storms and hurricanes were the target. But instead of producing rainfall for the benefit of growers in dry areas, cloud seeding would theoretically "rain a system out" over the ocean and prevent dangerous tropical storms from doing damage upon landfall, presumptuously on US shores. Unfortunately, it was concluded that the size and scope of hurricanes far outpaced our ability
to mitigate it. In fact, rather than being diminished, tropical storms were possibly being "steered". Obviously, the practice of intentionally driving a damaging storm into a location that would otherwise not have been hit under natural processes was fraught with potential litigation. Operation Stormfury came to a sudden and decisive halt forever. Still, the tantalizing prospect of controlling weather for the good of mankind was a tempting goal during this golden age of technology growth.
Hail canons have been used since the 19th century, theorizing that a sonic or shock wave aimed skyward into the thunderstorm might disrupt hail formation. In fact, changing the weather has been a staple of superstition for millennia. As far back as ancient India 3000 years ago, rishis (holy people) would chant mantras that ostensibly might bring rain. Witches in both Europe and the New World were thought to have abilities to conjure up good or bad weather. And there was a common belief that some Scandinavian peoples had the power to control weather. This was such a potent conviction that the Vikings refused to engage Finnish ships in battle on the sea. It is interesting
for me to note that some of the most brilliant founding meteorologists were Norwegian or Scandinavian; men like Vilhelm Bjerknes (who gave us primtive equations), Carl-Gustaf Rossby (Swedish- who gave us cold fronts and warm fronts - and Rossby wave theory), and Sverre Pe6erssen (to whom all meteorologists own a debt of gratitude for exceptional insight in his
groundbreaking 1940 textbook Weather Analysis and Forecasting). He discovered thermodynamic principles that are in utilized daily in modern meteorology. Petterssen also made the most important weather prediction in history: the D-Day invasion forecast. So what is it about the Scandinavians and weather? There must be something in the water. Today, weather modification is an element of military philosophy, scarcely known by the public. Weather warfare was occasionally utilized in Vietnam. Operation Popeye was an ambitious effort run by the Air Weather Service to increase rainfall along the Ho Chi Minh trail by 30%. A United Nations resolution from 1978 prohibits the military use of environmental modification techniques. Still, classified and nonclassified development is underway. "Weather-modification is a force multiplier with tremendous power that could be exploited across the full spectrum of war-fighting environments",
according to a 1996 research paper produced for the US Air Force. It is the fascinating inventory
into a bevy of possible concepts that many wouldn't even think possible. This look into the
future, entitled Owning the Weather 2025, is unclassified and available at:
Notwithstanding the failure of Operation Stormfury, efforts are still being conceived at universities, with clever ideas to minimizing potential hurricane intensity or even tropical storm formation. One theory calls for dropping oil on the ocean surface that would minimize evaporation and thus deprive the tropical system of its fuel source. Another forwarded by a company in Florida, is to disperse a substance called Dyn-O-Gel. This is a polymer (in powder form) that is advertised to absorb 1,500 times its weight in water. Clouds of a tropical system would lose a substantial fraction of their water droplet content, which would result in a weaker storm. These and other intrepid ideas continue to be discussed and implemented experimentally. Humankind has developed many new and exciting techniques that improve our lives, and at the same time minimize threats to our safety. Such is the case with meteorology that science marches forward to blunt the fiercest aspects of weather. An important part of hazard mitigation is preparedness.Numerous agencies, both public and private, continue to arm the public with knowledge and the means to shelter themselves from hazardous weather. Regarding tornadoes, we now stand at the pinnacle of modern science- able to predict the nearly exact location of a tornado threat, with the greatest lead-time in history. Underground storm shelters in tornado alley can save lives, even when an EF-5 strikes. The same capability may be stated about winter storms, tropical storms and even fire storms. It is information technology and instant communication that has allowed the US and other developed nations to meet dangerous weather head-on and live through it. As we step into 2013, weather that can't be modified (yet) can certainly be survived, through the exploitation of modern technology.