Technical and fundamental investors are fond of using indicators to divine which direction stocks may be headed. These cues can come from almost anywhere: interest-rate yield curves, put/call ratios, manufacturing surveys… you name it.

Some even use the Super Bowl as a prognosticating tool.

Personally, I monitor a wide variety of indicators, but only to keep my finger on the pulse of the global economy. There’s no silver bullet that accurately tells us when to buy and sell. If there were, someone would have uncovered it a long time ago.

That being said, if I were forced to pick a single barometer that could predict the weather for all types of assets, it would be China’s inflation rate.

It’s no secret that China has become the world’s growth engine. And the bullish outlook for natural resources in particular is predicated on the assumption that China’s booming economic expansion is fueling huge demand for coal, copper and just about every other commodity you can think of.

Any serious signs of deceleration (like we saw in 2008) could trigger a swift selloff. And inflation is the one roadblock that could prompt Beijing to deliberately step on the brakes.

Thanks in part to bold stimulus initiatives (and the stubborn refusal to let the yuan appreciate), prices have been on the rise, particularly in overheated real estate markets such as Shanghai. But we’re not just talking about property. Overall consumer inflation rates have remained above the government’s safety zone for nine straight months, touching 5.2% in March and 5.4% for the first quarter.

In response, the central bank has cut off the loose credit spigot. Bank reserve requirements have been tightened six times during the past six months, and interest rates were just hiked for the fourth time.

Those moves won’t automatically bring this locomotive to a screeching halt — gross domestic product (GDP) still surged 9.7% this quarter. But any cool-down will be met with a hostile reception from investors. With that in mind, I’ll be watching diligently for signs that China’s inflation-fighting tactics are blunting growth, but the train still seems to be chugging down the tracks.

And as long as China remains growing and hungry for natural resources, there are profits to be made. Especially in copper, a key building block for any rapidly growing economy. Copper wiring, for example, is essential in plumbing, power transmission, electrical circuitry and endless other applications. There’s no arguing that demand is on the rise. Prices on the London Metal Exchange recently touched $10,100 per ton — a new all-time peak.

And I think copper prices will move higher…

A few weeks ago, about 500 delegates representing mining companies near and far gathered in Santiago, Chile, for the 10th annual World Copper Conference came to the same conclusion: They won’t be able to meet the world’s demand for copper this year.

Action to Take –> I expect copper inventories to dwindle and prices to ascend further into record territory, possibly breaching $11,000 per ton. One of my top pick to tap into this supply/demand imbalance in Scarcity & Real Wealth is Freeport-McMoRan Copper & Gold (NYSE: FCX). The company (which mines 4 billion pounds annually) rakes in $260 million in incremental operating cash flows for every $0.10 increase in copper prices.

Profits are likely to explode as copper prices continue to climb…

P.S. — I recently put together a free webcast discussing another area where scarcity is rearing its head and offering investors a great opportunity to profit from a growing supply/demand imbalance long before the market’s conventional wisdom prices it in. Click here to view it.