Sunday, November 15, 2009

The Perils of Weather Modification

Weather Headlines

Weather modification backfires in China?

History of weather-tinkering in the USA

October weather to hang on most of this week (today & tomorrow the 2 nicest days in sight).

Best chance of light rain: Thursday, again Saturday

Turning colder by Thanksgiving: cold enough for a little wet snow NEXT Thursday & Friday?

A recent spate of record blizzards across northern China has created an uproar. Nearly 50 people have been killed during the heaviest snows in five decades across northern China's drought-stricken northern regions. Damage is estimated at more than $650 million; highways have been clogged, thousands stranded at area airports, with numerous reports of collapsed roofs north of Beijing. What makes the storm so controversial? Days before the Beijing Weather Modification Office conducted widespread cloud-seeding operations, boasting that "they had produced 16 million metric tons of additional snow." In a Wall Street Journal article a weather official, Zhang Qiang, was quoted as saying, "We won't miss any opportunity for artificial precipitation since Beijing is suffering from the lingering drought." Ouch. The timing is curious, but the truth of the matter: there is NO way seeding a few clouds could have created the record snowfalls (1-3 feet) measured over normally-arid northern China. It was an unfortunately-timed coincidence, but it points out the moral hazard of tinkering with Mother Nature.

Record-breaking snowstorms in the midst of a lingering drought. North China has been hit hard by heavy snow in the last week, paralyzing travel by air and land, collapsing buildings, leaving scores of people dead. The massive blizzard coincided with aggressive cloud-seeding conducted by the Chinese government in an attempt to end a decade-long drought.

During the 1970s, during a severe drought, efforts were made to seed clouds over North Dakota to try and squeeze a little rain out of a dry, dusty, summer sky. What happened next was also (probably) another example of crazy-coincidence: it POURED over the Red River Valley, and subsequent floods got farmers so angry that they petitioned to stop weather modification immediately. You could argue the cloud-seeding worked too well! Since then there has been no weather modification (to my knowledge) anywhere east of the Rockies. Many western states routinely operate weather modification exercises, attempting to nudge the weather in a certain direction. Cloud-seeding over the Sierra Nevada mountains of California have been shown to spike snowfall by 3-5%, but only when conditions aloft are ripe. Salt Lake City's airport has dropped dry ice into ice fogs, hoping to dissipate ice crystals and clear runways, with some level of success. But the energy necessary to create widespread, heavy rain (or snow) is something that just isn't in the realm of reality anytime soon.


In recent years the one area of weather modification that has gotten the most attention revolves around hurricanes. Although it's probably impossible to nudge a hurricane in any specific direction - the notion of weakening a hurricane is very possible, at least in theory. Since hurricanes thrive on warm ocean water, if you could somehow cool water temperatures in the path of a hurricane, you MIGHT be able to knock down wind speeds (and subsequent storm surges and damage). Scientists have devised amazing technologies for bringing cool water deep in the ocean to the surface; even Microsoft's Bill Gates got in on the action by filing a patent for a process that might weaken hurricanes by cooling the water in their path.

Project Stormfury. In the 1960s attempts were made to weaken a handful of hurricanes approaching the U.S. coast. The theory: by seeding the outer eyewall it might be possible to strengthen the thunderstorms farther away from the center of the storm, widening the eye, and subsequently weakening the strongest winds in the process. Although some of the initial results were promising, nearby nations complained that the USA was "stealing their rain", so the experiments were halted.

But tinkering with the weather is fraught with peril, technological and political. During the 1960s, during Project Stormfury", researchers attempted to seed the inner eyewall of Hurricane Debby, off the coast of Florida, with silver iodide, hoping to weaken the raging donut of towering thunderheads. Sure enough wind speeds dropped by 30% immediately after the Hurricane Hunter aircraft seeded the core of the storm. But after getting wind of the experiment, countries like Cuba and Mexico complained to the United Nations that America was "robbing them of their life-giving storms." Bowing to international political pressure the hurricane researchers halted their flights into hurricanes, and there hasn't been any attempted modification since. Sometimes I'm asked, "Paul, couldn't you just detonate a nuclear weapon in the eye of a hurricane?" Hmm. Hurricanes get their strength from warm ocean water. Let's heat the water to a million degrees F. in a few milliseconds! Truth: such tinkering could make a hurricane even more fearsome, not to mention what would happen to radioactive fallout. Similar suggestions have been made for tornadoes. "Just launch rockets into the funnels to disrupt the violent vortexes!" Great idea, Einstein. But what happens if your artillery shell MISSES and you hit a nearby neighborhood.

Rest assured - weather modification (on a large and devastating scale) is still the stuff of science fiction, not reality. And no, I haven't seen any credible evidence that the Russians (or anyone else) are using low-grade radio frequency waves or any other esoteric methods to disrupt the weather patterns over North America. Again, the energy required to really have a widespread impact on a storm 1,500 miles wide boggles the mind, and is outside the realm of reality. At least in our lifetime.

I hope you were able to sneak outside yesterday and play in the sun. Does rake leaving qualify as "playing"? I took my '85 convertible out for a spin. I can't remember the last time I was able to do this in mid November. No complaints here. I consider this payback for an especially rotten October. The mercury topped out at 49, well above our average high of 40 for Nov. 15. A year ago the high was 37, by comparison. No snow (yet) in November - we should have seen about 3-4" by now. A fairly quiet week is on tap, today and Tuesday probably the nicest days in sight with highs near 50 over parts of central and southern Minnesota. A Colorado storm will strengthen over Tulsa, Oklahoma tomorrow, then push almost due north, spreading a few light showers into town by Wednesday night and Thursday, but rainfall amounts don't look impressive. Looking farther ahead a little rain or drizzle may fall Saturday, followed by sunnier, drier weather on Sunday as temperatures cool a few degrees. Nothing remotely resembling a "cold front" is in sight this week, temperatures consistently 5-15 degrees above average for this time of year. The Weather Honeymoon continues.

Now, about Thanksgiving. Although I don't see any monstrous, flight-mangling, highway-battering snow/ice/rain storms between now and Thanksgiving, the long LONG range computer models are strongly hinting at a cool-down right around Thanksgiving, even suggesting a slushy inch or so of snow on Thanksgiving and "Black Friday", the shopping (mess) the day after we all consume far too much turkey and stuffing. But winds are forecast to be blowing from the north/northwest, so I can't get too excited (or concerned) just yet. Our flow aloft will be "modified Pacific" through much of next week, so expect our run of October-ish weather to hang on for the better part of the next 10 days. I can live with that....

Paul's Outlook for the Twin Cities

Today: Mostly sunny & beautiful. Winds: light, under 5 mph. High: 51

Tonight: Clear and frosty. Low: 26

Tuesday: Bright sun, still feels more like mid October. High: 50

Wednesday: Sunny start, then increasing clouds. High: 46

Thursday: Overcast, a little light rain possible. High: 44

Friday: Mostly cloudy, cool and damp. High: 43

Saturday: Still gray, a little light rain or drizzle possible. High: 46

Sunday: Partial clearing, breezy and cool. High: 43

No comments:

Post a Comment