Some 12.3 million jobs were lost during the Great Recession, according to a recent report by the Brookings Institute and the Hamilton Project. For those who were able to find new work, wages decreased from $43,700 per year to $23,000 annually two years after the initial job loss, a 48 percent decrease. Current unemployment figures show that many people who lost jobs in the downturn are still unable to find work. The latest unemployment figures show that more than 8 percent of Americans are unemployed. Many more have simply stopped looking.

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The steep wage reductions and chronic unemployment indicate that the pre-recession U.S. economy is not likely to come back. In many places, well-paying manufacturing jobs have disappeared for good. If the workers who held these jobs don't learn new skills, the United States is at risk of creating a permanently unemployed class that lacks the skills necessary to thrive in the modern workforce.

These workers need to change, and quickly. According to experts, one of the quickest avenues to change and one of the fastest-growing areas of the world economy is the green sector. Businesses involved in alternative energy, green construction, conservation, and environmental management and cleanup strive to create economic growth in environmentally friendly, sustainable ways.

Focus on building a green economy has intensified as concerns about global warming and climate change have increased. Industries that rely heavily on fossil fuels are under pressure to switch to more environmentally friendly methods. Recent reports show that hundreds of billions of dollars are invested in the green economy each year.

Green job experts say the existing skills of many workers who lost manufacturing jobs in the downturn make them prime candidates for green work. All that's needed is some patience, retraining, and a willingness to accept the risks of a quickly evolving sector.

Educated workers in demand. Ezra Drissman, manager of Internet operations at GreenCareersGuide.com, a green industry job board, says educated workers like engineers and architects are already in demand across green industries.

"The engineers always come out ahead," he says. "They're in demand because their job is to find a better way of doing things."

Blue-collar workers who lost their jobs in the recession can also leverage their skills for jobs in the green industry, Drissman adds. For instance, someone with solid manufacturing skills has the basic skill set necessary to install solar panels, one of the fastest growing sectors of the green economy, he says.

"You will see the need for solar installers go up and increase quite a bit … I think we're one to two years away from it taking off," Drissman says. "For people who have been laid off by companies like General Electric or Chrysler, a one year retraining is crucial."

Drissman acknowledges that the training required for entry into this workforce, as well as the dramatic change of industries, might frustrate workers.

"With any new technological revolution, the blue-collar workers and really specialized skills are going to have the hardest time readjusting," he says. "But the jobs that end up being created are way better than the ones they had 50 years ago. The potential here really is phenomenal."

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Placement, on the ground. There are numerous websites that advertise green jobs. But one of the more unique is BaltimoreGreenCareers.org, run by the Baltimore Center for Green Careers. According to the site, the center is "dedicated to the creation of business and employment development initiatives that contribute to environmental sustainability and are open to all Baltimore job seekers."

John Mello, green projects director for Baltimore nonprofit organization Civic Works, says the goal of the center is to place blue-collar and disadvantaged workers into green jobs that have the potential for growth.

"Some of [the workers placed by the Center] were working in blue-collar industries," Mello says. "A lot of folks come to us with a broad labor experience. We service anyone in Baltimore who is unemployed or underemployed."

Mello says workers placed by the center primarily work in the cleanup of brownfields, or cites the Environmental Protection Agency defines as "a property, the expansion, redevelopment, or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant." They also work in other structures that contain potentially dangerous substances like asbestos.