One of the frustrating aspects of weather is our inability to control it.  For farmers, massive hailstones can cause millions of dollars damage.

Attempts to seed clouds to increase precipitation, disperse fog, or suppress hail have been carried out since the 1940s.  The most commonly used technique is to spray clouds with substances like silver iodide, dry ice, or liquid propane, which act as ice forming agents.

Those in the weather modification business claim increases of five to twenty percent for winter precipitation, and even more for coastal areas.  Suppression of hail is, they claim, twenty to fifty percent effective.  All this is dependent on the presence of clouds that are close to producing
precipitation, so cloud seeding can never halt a drought.

This is a controversial area of technology.  Cloud seeding is not well studied scientifically, and unintended consequences remain unknown.  Opponents worry about simply "robbing Peter to pay Paul".  They believe that cloud seeding to enhance rainfall or reduce hail fall without any bad impact seems too good to be true.  Critics would like to see cloud seeding companies legislated like drug companies, who have to prove a drug's efficacy and safety in clinical trials before they market it.

So next time you wish you could change the weather, remember that in some cases it might just be possible.

MOVING BEYOND MATTER
 by Christopher Shennan

For most of us, weather is no big deal.  Sure, our heating bill goes up in the winter, and we find humid summer days a little hard to bear.  But  in some regions weather has a much more devastating affect.  In Bangladesh, for instance, in 1998, devastating floods drove more than a million people to take refuge in flood shelters.  918 people died.  The death tool for cattle approached 27,000.  Well over 14 million acres of standing crops were affected.*

These figures represent more than a mere inconvenience, or even tragedy for an isolated few.  They depict a tragedy that wrecked the economy of an entire nation, and dealt another hard blow to people already in the grips of grinding poverty.  In spite of wonderful scientific advances, no one could do anything about this.  And this was only one of the many weather-related tragedies of the last century.

Weather is serious and uncontrollable.  And so perhaps we shouldn't be surprised that it sometimes becomes the subject of humour.  Somehow it's easier to deal with problems when we can laugh at them.

A fictitious story is told about a farmer who argued with God about the way He was handling the weather.  So, at last, God agreed to put the weather under the farmer's control just for one season.  And with satisfaction the farmer accepted the challenge.  

He carefully regulated rain and sunshine, and made sure the ground was just right for planting and in his mind's eye he could see mountains of corn in a bumper crop.

Imagine his dismay when he discovered that not one corn cob had developed.  No corncobs, no corn were to be found on any stalk.  He complained to God, "What's going on here?  Are You trying to sabotage my crops?"

"I did nothing at all."  God replied, "You forgot the wind.  Without the wind pollination can not take place, and without pollination no crop can be produced."

So have you noticed that though we've learned a lot about controlling the environment, we still can't get everything right?