"It's time to bail out the people and the planet," says Van Jones , author of The Green Collar Economy: How One Solution Can Fix Our Two Biggest Problems . We agree, and this guide to to sustainability-focused career paths will help retrofit and solar-charge your work life.
America has only two million farmers, and their average age is 55. Since sustainable agriculture requires small-scale, local, organic methods rather than petroleum-based machines and fertilizers, there is a huge need for more farmers -- up to tens of millions of them, according to food guru Michael Pollan. Modern farmers are small businesspeople who must be as skilled in heirloom genetics as marketing.
Schools: University of Vermont: Center for Sustainable Agriculture; Stone Barns Center For Food & Agriculture in New York State; University of Oklahoma: Kerr Center for Sustainable Agriculture; Evergreen State College: degree in Sustainable Agriculture.
Related careers: urban gardener; farmers market and CSA coordinator; artisanal cheesemakers; and other food producers.
Modern forestry is a complex combination of international project finance, conservation and development. According to the World Bank, a staggering 1.6 billion people depend on the forest for their livelihoods. Foresters help local people transition from slash-and-burn to silviculture--teaching cultivation of higher-value, faster-growing species for fruit, medicine or timber, for example while carefully documenting the impact on the environment. Deforestation, which causes around a quarter of all global warming, is also likely to be a leading source of carbon credits worth tens of billions of dollars .
Schools: Yale School of Forestry and Environmental Studies; Duke University: Nicholas School of the Environment; University of Michigan: School of Natural Resources & Environment.
Companies/organizations: The Nature Conservancy; New Forests Inc.
Solar Power Installer
Making and installing solar power systems already accounts for some 770,000 jobs globally. Installing solar-thermal water heaters and rooftop photovoltaic cells is a relatively high-paying job--$15 to $35 an hour--for those with construction skills. And opportunities are available all over the United States, wherever the sun shines. Currently over 3,400 companies in the solar energy sector employ 25,000 to 35,000 workers. The Solar Energy Industries Association predicts an increase to over 110,000 jobs by 2016 -- even more if anticipated tax credits are accelerated .
Companies: Akeena Solar; Sungevity; Sunpower; Full list at SEIA.org.
Energy Efficiency Builder Buildings account for up to 48 percent of US energy use and greenhouse gas emissions. LEED, the major green building certification, has over 43,000 accredited professionals . But the cutting edge in efficient buildings goes far beyond LEED. Buildings constructed according to Passivhaus and MINERGIE-P standards in Germany and Switzerland, respectively, use between 75% and 95% less heat energy than a similar building constructed to the latest codes in the US. Greening the US building stock will take not only skilled architects and engineers, but a workforce of retrofitters who can use spray foam insulation and storm windows to massively improve the R-value (thermal resistance) of the draftiest old houses. A study by the Apollo Alliance recommended an $89.9 billion investment in financing to create 827,260 jobs in green buildings -- an initiative supported by the Obama stimulus package, which specifically mentions energy retrofits .
Schools: Arizona State University School of Architecture: Energy Performance Climate-Responsive Architecture; University of Michigan: Alfred A. Taubman College of Architecture + Urban Planning; The Earth Institute at Columbia University.
Wind Turbine Fabricator
Wind is the leading and fastest-growing source of alternative energy with over 300,000 jobs worldwide. Turbines are 90% metal by weight, creating an opportunity for autoworkers and other manufacturers to repurpose their skills. According to the American Wind Energy Association , the industry currently employs some 50,000 Americans and added 10,000 new jobs in 2007. Their job board  is an excellent place to start looking for opportunities.
Companies: Vestas; Siemens; GE Energy.
Conservation Biologist The granddaddy of diversity, E.O. Wilson, famously called conservation biology -- a discipline with a deadline. The urgent quest to preserve the integrity of ecosystems around the world -- and to quantify the value of -- ecosystems services -- leads to opportunities in teaching, research and fieldwork for government, nonprofits, and private companies. The forthcoming economic stimulus package from the Obama administration offers the prospect of increased federal support for science and research .
Schools: Center for Conservation Biology at the University of Washington and the Center for Conservation Biology at Stanford University. At the small College of the Atlantic  every student gets his or her degree in human ecology; it's been called the most sustainable college or university in the world.
Green MBA and Entrepreneur
The concept of the triple bottom line  has migrated from the margins to the mainstream of the business world. A recent report by the U.S. Conference of Mayors, Mayors Climate Protection Center found that business services like legal, research and consulting account for the majority of all green jobs -- over 400,000. This includes everything from marketing to the LOHAS (Lifestyles of Health and Sustainability) segment, to serving as a VP of sustainability within a large company, to piloting a green startup like Method or Recyclebank.
Schools: Stanford School of Business; San Francisco's Presidio School of Management; Leeds School of Business; University of Colorado at Boulder -- Deming Center for Entrepreneurship; the Bainbridge Graduate Institute in Wash.
Recycler The total number of recycling jobs in the United States is at more than 1 million, according to recent reports  (PDF, right click to save). Although the market for paper and plastic has slowed down recently due to the economic downturn, demand for steel is still strong -- 42 percent of output came from scrap in 2006 -- and recycling remains the economical alternative to high disposal fees. Worldwide more than 200,000 people work in secondary steel production, and the US is a major center of production. New laws and regulations  are also creating a need for specialized companies that can close the loop by recycling and repurposing e-waste, clothing, plastic bags, construction waste, and other materials.
Companies: Rumpke; Greenstar North America.
Sustainability Systems Developer The green economy needs a cadre of specialized software developers and engineers who design, build, and maintain the networks of sensors and stochastic modeling that underpin wind farms, smart energy grids, congestion pricing and other systems substituting intelligence for natural resources. Coders with experience using large scale enterprise resource planning have an edge here, as well as developers familiar with open source and web 2.0  applications.
Companies: IBM, V2Green, WindLogics
Urban Planner Urban and regional planning is a linchpin of the quest to lower America's carbon footprint. Strengthening mass transit systems, limiting sprawl, encouraging use of bicycles and deemphasizing cars is only part of the job. Equally important is contingency planning, as floods, heat waves and garbage creep become increasingly common problems for metropolises. Employment in this sector is projected to grow 15 percent by 2016, and the jobs are mainly in local governments, which make them a slightly safer bet for the downturn.
Schools: Penn Institute for Urban Research ; Harvard: Department of Urban Planning and Design; Portland State University: Nohad A Toulan School of Urban Studies and Planning.