"While global climate change may be over-politicized, there's no disputing that the issue is real," says Larry Edelson. In his Real Wealth, he looks at two favorite exchange-traded funds that invest in the water sector.

He explains, "Food shortages and the lack of fresh drinking water are likely the most acute and immediate problems. For example, Northwestern India is running out of water, China is raising water prices to curb use and Mexico recently restricted the water supply amid a shortage.

"Domestically, unbridled use of groundwater in Arizona is a potential disaster. The problem is pipelines and canals don't extend far enough to deliver water to everyone. And unrestrained drilling in outlying areas is draining the supply.

"What is one thing you can't live without?" asks Brandon Clay and Ron Rowland. "Take away that glass of cool, clean drinking water from your diet, then it's a matter of days before you dehydrate and die." ons

In All Star Investor, they explain, "Water is essential to our survival." And for investors, they add, "Powershares Water Resources Portfolio (ASE: PHO) is a perfect play on the global demand for water technology."

"The essential nature of water is the same for the 6.67 billion people on this planet. With Latin America and Asia entering the modern world at an unprecedented pace, water is becoming even scarcer.

"Improving diets and growing industry have pushed this diminishing resource further from the reach of many people. Yes, people are still drinking water, but at what cost?

"Water covers most of our planet. Still, less than 2% is fresh water. That makes water a limited resource. Consumption is growing with 6,000 cubic meters per inhabitant used every year. That's the equivalent of draining Lake Superior – the biggest lake in the world – twice. Since the water cycle is not replenishing growing demand, water sources are being depleted.

"We've been tracking the water industry for a while and it's been crystal clear that water is an area we want to dive into," says Toby Smith in his ChangeWave Investing. Here, he looks at a water-focused ETF.

"Water is often taken for granted, but that is changing. A combination of global economic growth and years of neglect are leading to a tidal wave of demand for water infrastructure and various technologies.

"It's forecasted that by 2025, almost two-thirds of the global population will live in countries where water will be a scarce commodity. Climate change could exacerbate the problem. Clearly, water issues cross all boundaries.

The water industry combines the best attributes of a good defensive strategy coupled with numerous 'offensive' plays. From a growth perspective, spending on water projects at all levels is on the upswing due to years of infrastructure neglect and under-investment.

"One great way for all investors to participate is by investing in an ETF with a water focus, such as PowerShares Water Resources (NYSE: PHO).

"The beauty of this water ETF is that it gives us exposure to each of the companies that were highest rated in our survey (comprising approximately one-third of the PHO holdings). PHO also has a well-balanced portfolio, with no single stock representing more that 4% of the total. IN our view, it's clear that the water industry will see above-average growth well into the future."

Each day, Steven Halpern's TheStockAdvisors.com offers the latest market commentary and favorite investment ideas from the nation's leading financial newsletter advisors.

"Water is the sleeper investment of the decade," says Jim Powell. "Although the world is focused on energy, clean water is in far shorter supply in many regions. That's even true in many parts of the U.S."

The editor of Growth Stock Alert suggests, "A great deal of money will be made by today's earlybird investors who buy strategic water stocks." Here are his favorites in the sector.

"Unlike oil, there is no substitute for water. Some investors mistakenly think that water is a low value commodity that's not likely to deliver good profits. What the critics fail to consider is the equipment needed to
obtain, purify, transport and recycle water is very expensive.

"Calgon Carbon (NYSE: CCC) is my first choice in a water stock. The company is the world's largest supplier of
granulated activated carbon, the principal purification agent for water. The company also supplies complete treatment systems for municipalities and private organizations.

"The company has 16 operating centers and 23 sales and service offices around the world. A few years ago

, the company expanded its purification business to include industrial liquids and gasses. Rising concerns about greenhouse emissions and other pollutants are giving Calgon Carbon another boost.

"I also recommend ITT Corporation (NYSE: ITT), the world's leading supplier of systems that move and purify
water. The company's treatment equipment is sold throughout the world under the Sanitaire, Aquious and WEDECO brands.

"Water in all it uses is in short supply all over the world," says Richard Lehmann. Here, in his ETF Advisor, he reviews exchange-traded funds that invest in the water sector.

The advisor comments, "A CIA analyst once stated that Iraq's water was far more valuable than its oil." Indeed, he points out that in South Florida, which is currently experiencing a drought and severe water use restrictions, some advocate a ban on all new development while others encourage a water desalinization plant.

He continues, "The lack of potable water in the African sub-continent has been the subject of much international interest as a problem that is solvable with current technology."

For investors seeking exposure to the water sector, he notes that there are three water related ETFs on the market: PowerShares Water Resources Portfolio (ASE: PHO), First Trust ISE Water Index Fund (ASE: FIW) and the Claymore S&P Global Water ETF (ASE: CGW). He observes that all three ETFs have roughly the same expense ratios of around 0.65%.

The most recent entry, he points out, is the Claymore S&P Global Water. He says, "The ETF is unique in that it takes a global perspective to the water industry and invests in 50 companies distributed throughout the world. The investments cut across market capitalization sizes and range from small to large."

Companies in its portfolio, he notes, are divided into two groups: water utilities and infrastructure, and water equipment and materials. He says, "We think this is the best of the three since it encompasses a wide variety of geographic regions, with the US market representing only 28% of their holdings."

For more stock picks from the leading financial newsletter advisors, visit Steven Halpern's free daily website, TheStockAdvisors.com.