Under- the -Weather Man

In late September, I would never have guessed that I would spend the next week in St. Vincent's Coronary Care Unit following a heart attack. John Day suffer a heart attack? Fortunately, it was a slight one caught in time. Dr. Warren Sparks was on duty at the Columbia Willamette Valley Medical Center emergency room. Fortunately for me, he is a great doctor.

As I was sitting in the emergency room with daughter, Patti, she heard another person passing through say, "I recognize that guy with the white mustache. He's the Weatherman." He should have said, "He's the Under-the-Weather man," for that is what I was at the moment.

Dr. Sparks, in consultation, ordered a trip by ambulance to Providence St. Vincent Medical Center in Portland. And has stayed an hour beyond his normal shift time to see me on my way. Love in action.

From my room on the sixth floor with a picture window view to the north overlooking a fir forest, I could see a continually varying panorama of clouds. In my room a Mylar balloon tugs at its tether. "Sorry to hear that you are under the weather" is printed on its side, with a picture of Donald Duck shedding rainfall from a dark overhead cloud.

Why does it tug upwards? This question gives me the opportunity to pursue the topic of the ups and downs of weather from my last column. The upward tug is the buoyant force which in this case is greater than the downward force of gravity.

The father of the concept of buoyancy is the great Archimedes, about 250 B.C., chief wise man of the city state of Syracuse at the boot of Italy. He had been challenged by his king to solve a mystery, namely, were his goldsmiths ripping him off and adulterating the precious metal to be used in his new crown with a base metal that looked like gold, but wasn't.

Archimedes pondered the problem at length. Then, one day, while using the public baths, the answer came to him. He weighed less when immersed in water than when immersed in air. In exultation he rushed down the city street naked as a jay bird shouting "Eureka, Eureka."

The Archimedes Principle, central to understanding the workings of the weather goes as follows: any body immersed in a fluid is buoyed up by a force equal to the weight of the fluid displace by the body.

My Mylar balloon tugs upward because the weight of the air it displaces is greater than the weight of the Mylar skin and the helium enclosed.

Because of its importance, I have my meteorology students at Linfield College recite this like a mantra.

As I look out my windows, I see change taking place in the cloud structure. Early on, the predominant cloud was stratified cumului, which have very little, but some buoyancy. Now, there is growing evidence of increasing buoyancy producing rising cumulus towers. Why rising? Because of the upward buoyant forces.

Buoyancy occurs in two forms: elevator and parking structure. Let me explain. The aforementioned cumulus are a consequence of elevator buoyance. The buoyant column rises vertically as does an elevator. And the air rises as a series of vortex rings, like smoke rings.

As I write, I look down on St. Vincent's four-story parking structure. Cars don't get to the roof by an elevator. They drive up a long inclined plane, round and round. Atmospheric buoyance sometimes manifests slowly as one air mass slowly rises over an inclined plane, such as a warm frontal surface.

My clouds as I view them this afternoon are no longer cumulus, but the sky is full of thick gray, layered masses, soon to become nimbostratus with rain.

The battle between the ups and downs goes on continually on scales ranging from microscopic to global. El Niño, so central to the news, is a semiglobal battle between the ups and downs in the grand weather scheme. We shall have more to say on this top in future columns.