The glass is half-empty these days for whisky-drinkers with a taste for Scotch, as a worldwide shortage is beginning to make the alcohol more difficult to find – and more expensive.

Scotland's stock of barrel-aged whisky is running low, due to higher-than-anticipated global demand for the luxury alcohol. And because Scotch needs to be aged for 10-25 years, suppliers can't simply whip up more to meet the current demand.

Alcohol historian Rod Phillips says distilleries in the 1990s and 2000s did not anticipate the drink becoming as popular as it now is in Asia, where many have developed a taste for it. Japan, China, South Korea and Singapore have all seen a huge boom in the demand for Scotch, Phillips said.

"There's a big demand for prestigious and luxury alcohols in general," Phillips told CTV's Canada AM on Friday. "They didn't expect this kind of demand, so they simply didn't prepare with enough whisky in the barrel."

Scotch is a luxury type of whisky made exclusively in Scotland, and typically aged in barrels for several years. "You buy a bottle of Scotch that's 25 years old or 18 years old – that refers to the youngest whisky in the bottle," Phillips said.

But it's not all bad news for whisky-drinkers. Scotch whisky might be more difficult to come by these days, but Phillips says there are many other great whiskies produced in different parts of the world.

"There could be an upside to this shortage, and that is that people may move away from drinking what is a bit of a cliché," he said.

For instance, Crown Royal's Canadian-produced whisky, Northern Harvest Rye, was recently named "whisky of the year" in the Whisky Bible. The drink has been flying off the shelves ever since, though it, too, could dry up due to a strike at the Manitoba distillery where it's produced.

Phillips said the shortage probably won't affect most people in a significant way.

"To most consumers, it doesn't mean anything, to be honest," he said. "It could just lead people to be more adventurous in their whisky-drinking."