Worldwide sales of light vehicles are expected to increase this year, albeit slowly, with a major caveat to those growth projections being the outcome of Europe’s sovereign debt issue.

The research was conducted by Polk & Co. and Fitch Ratings.

Polk projects that worldwide sales of new light vehicles this year should rise 6.7% over 2011 volumes to 77.7 million vehicles, with gains anticipated in all global regions except Europe.

China is expected to make the largest contribution to global sales growth for new vehicles, according to Polk, with an anticipated 16% increase in sales over 2011, with much of that growth occurring outside of the large metropolitan cities of Shanghai and Beijing.

By contrast, European sales are expected to be flat or down slightly, to just over 19 million units, Polk said, as austerity plans will prevent governments from boosting 2012 sales through “scrappage” programs (such as the U.S. “cash for clunkers” effort in 2009) and other incentives offered in previous years.

Polk’s analysts predict that the U.S. market will experience 7.3% growth to 13.7 million vehicles, primarily due to the relatively strong year for sales in 2011 combined with a weakening economy that will continue to impact new vehicle demand through most of this year.

The company added that it doesn’t expect the U.S. market to achieve pre-recession sales levels greater than 16 million light vehicles per year until 2015.

That dovetails with the outlook offered by Fitch Ratings, which noted that U.S. light vehicle sales are likely to grow this year to 13.2 million units; a figure well below the industry annual sales level of approximately 17 million units seen from 1999 through 2006.

“We believe the U.S. industry may struggle to exceed annual sales of approximately 15 million light vehicles at the peak of the current demand cycle,” Fitch said in its 2012 Outlook: U.S. Auto Manufacturers and Suppliers report.

On a more positive note, Fitch pointed out that U.S. automakers are now more “resilient” and can better withstand a significant drop in vehicle sales.

“Relative to the last downturn, [OEM] operating profiles are more resilient as a result of capacity reduction, lower fixed costs, and a more manageable labor cost structure linked to the recently ratified United Auto Workers (UAW) contracts,” Fitch said.

“We estimate that the break-even industry sales level for the Detroit Three and major parts suppliers is now about 10.5 million light vehicles, corresponding to 2009 recessionary sales volumes,” the firm added.