According to the U.S. Department of Labor, “The green economy encompasses the economic activity related to reducing the use of fossil fuels, decreasing pollution and greenhouse gas emissions, increasing the efficiency of energy usage, recycling materials, and developing and adopting renewable sources of energy.” This presumably reflects the thinking about “green” jobs in the real economy of the United States, which prioritizes the continued energy and material flow through our civilization and the availability of those parts of “the environment” that people directly use.
The use of the term “green” triggers imagery consistent with a natural setting dominated by plants, and by extension, more biodiversity. Rightly, many of us tend to associate this with a better life. Unfortunately, because the green economy as presently defined only peripherally addresses a few of the causes of our biosphere's degradation, and is likely to exacerbate others, the result is not likely to match our expectations from the imagery.
Biodiversity loss is perhaps the largest single manifestation of biosphere degradation. Habitat loss, population growth, and invasive species (three of the five largest causes) may actually increase as a result of green activities, and the continued reliance of green technologies on electronic technology may not alleviate the pollution problem (the fourth cause) outside of a very narrow range of harmful substances. Habitat loss is a consequence of our appropriation of land and other resources from use by wildlife, which is likely to increase as we mine more materials for new technologies, build more buildings, erect large-scale wind and solar installations (along with their distribution and transportation infrastructure), and devote land to the growth of biofuels. More efficient resource use tends to drive up consumption because people feel free to use more (viewing the savings as the equivalent of new resources); and as per-capita consumption increases, so does population (enabling full use of the available resources). Wherever people go, other species go with them, among them our favorite monoculture crops, often displacing the natives and sabotaging ecosystems. Now, with biotechnology and species bred for biofuel use, we can introduce a range of new species that may wreak even more havoc.
If we were to more broadly define the goals of a green economy to include a healthy biosphere where people use only what can be replenished without harm to each other and other species, we might truly have a healthier world as a result. It is almost certain to be very different from what we currently have, so different perhaps that a job classification system like the one used by our government wouldn't even be meaningful.