It's no secret that the airline industry produces an enormous amount of greenhouse gas emissions, specifically CO2 (carbon dioxide). In fact, it's estimated that airlines produce approximately 2 to 3 percent of all manmade CO2 emissions, which many scientists believe are a leading cause of climate change.

Yesterday, United Airlines CEO Oscar Munoz revealed that United had committed to reducing the company's greenhouse gases 50 percent by 2050. According to Munoz:

Achieving this goal would eliminate 21 million metric tons of CO2 in the atmosphere per year, or the equivalent of taking 4.5 million cars off the road; that's all the cars in Los Angeles and New York City combined.

While this announcement makes United the only U.S. airline to commit publicly to reducing its greenhouse gas emissions, when Oscar Munoz talks, the industry listens. I wouldn't be surprised if American, Delta, Southwest, and other airlines soon follow United's example.

Part of United's commitment will be fulfilled by using less fossil fuel, which will be accomplished by burning biofuels (which are produced from such things as seaweed and agricultural waste) instead of regular jet fuel. To this end, today United will fly the longest biofuel flight to date in the industry -- Flight 44 from its hub in San Francisco to Zurich, Switzerland -- using 16,000 gallons of biofuel blended with regular jet fuel in a 30:70 ratio.

According to Munoz, while United's commitment to reduce greenhouse gas emissions will be good for the earth, it will also be good for the company's bottom line. Says Munoz:

The price of oil went up by nearly 50 percent in the past year, and prices are expected to continue to rise. Fuel costs us more than $15,000 every minute. In fact, we spend more on fuel than ground operations, facilities, and landing fees -- combined. So, when investors and analysts demand to know how we intend to control fuel costs and increase profits while keeping ticket prices low, our sustainability advantage becomes crucial.

Again, when Munoz talks, the rest of the airline industry listens. We'll soon see if United's competitors get on board -- or let this one fly right on by.