The world has endured (survived?) two of them.

They led to transformations in energy use and economic activity twice in the modern era, in 1973-74 and 1979-1980.

They are oil shocks, and right now Daniel Yergin, chairman of Cambridge Energy Research Associates, argues in a Financial Times column that what is unfolding before us is the world's third oil shock. (Oil traded Thursday at $128.60 per barrel.)

Further, Yergin argues that those who say the world could take $80 per barrel oil in stride amid strong economic growth should not feel emboldened about the world's ability to continue to grow with an oil price that's $60 higher in the near future. The contraction ripples have started. In the airline sector. In the auto sector. Note the lighter traffic at your local mall. And did you notice that last food bill for the same shopping cart of items you bought?

Bad news, good news

Yergin's bad news? (And short-term, it is bad news.) Supply, short-term, will not be able to prevent the shock, in other words, lower prices to levels that would maintain (restore?) adequate global economic growth. Engineering skills and oil equipment are in short supply, drilling costs are rising, and equally damaging, selected governments are restricting access or postponing decisions that would bring more oil to the market in the shortest possible time.

Yergin's good news? Demand is already responding to record-high oil (and in the U.S., gasoline) prices, except in those countries where prices are controlled or subsidized. The oil shock is propelling changes (finally) in public policy, corporate/consumer behavior, along with technological development and implementation. Hybrid cars/vehicles, once fringe, are now in demand. The U.S. Congress increased automobile fuel efficiency requirements for the first time in 32 years. And billions of dollars have been added to speed the development of battery technology.

Coal. Detestable coal.

Politically incorrect coal.

The stuff of Dickens' England. Black-lung disease. Strip-mining. And global warming.

Coal is the 'Rodney Dangerfield of energy forms,' because, like the late comedian, it gets no respect.

Have you ever heard of a positive association regarding coal? As a child in the United States, way back in the twentieth century, you dared not misbehave prior to the holidays, lest you get, coal in your stocking.

(No one ever spoke of a reprimand involving 'getting oil in your stocking.' No sir. Oil is considered 'black gold.')

Well, in the near future you and many others may look favorably on collecting coal, and a lot of it, if current trends continue regarding that other notable energy form, oil.

The oil surge, which gives new indications daily that it's evolving into the world's third oil shock, bodes tougher times for airlines, and travelers alike, many analysts agree.

Moreover, those tougher times may propel "creative and avant-garde" ideas and strategies to cope with the more-challenging flying environment, by both airlines and travelers, so says C. Leonard Bauer, independent stock analyst.

American Airlines (NYSE: AMR) took the first, bold - - and controversial - - step in the 'era of new flying rules' by announcing that it would charge passengers $15 each way to check their first bag, The Dallas Morning News reported. American also reduced its flying schedule by 11-12% at the same time.

Bauer said travelers should brace for more a-la-carte changes from the major carriers, and some truly creative ones, at that. "The airlines will be looking at every way to reduce fuel usage and cover those expenses from added weight," Bauer said, "When oil was at $20 a barrel, weight was a cost factor, but now at more than $125 a barrel, it's a going-concern factor. These high fuel costs can and will force some airlines out of business if they can't recover these costs. 'Light flight' is in." Bauer added that he does not have a rating on nor own shares of any airline.