The Real Poop
This planet is going to the crapper. We did it. Nobody else to blame. Not even a meteor. We are in the Anthropocene Era. It's not too late to save Big Blue Marble, however, and that's where environmental scientists come in. Indiana Jones with no shoes. It is an environmental scientist’s job to analyze the effects of various pollutants in our air and water supplies, convince corporations and governments to institute policies and pass laws that will protect and preserve the environment, and hug trees (a few environmental scientists have allowed it to go a little further than that, but you will be happy to know that they are now in jail and off our streets).
And more darkly, it is environmental scientists who sell themselves to sign off on construction sites knowing that they will kill indigenous life. The world needs environmental scientists with slightly higher moral standards than these sell-outs. People who are less concerned about getting the green and more concerned about being green.
You must have a strong background in math and the sciences, have great oral and written communication skills (as you will need to spend much of your time convincing cigarette-flicking, non-recycling goobers that what you do is worthwhile), and have the versatility to work in a lab, in an office, or out in the field. (It's not a literal field. What do you think you’re going to be doing—picking wildflowers?)
Most environmental scientists are employed either by the government or by a science and engineering company. Others work for oil and gas companies, and still others run their own businesses. You know that "Environments 'R Us" place down on the corner? That was obviously started up by some enterprising young environmental scientist.
"August 12: Tree still looks pathetic."
On the upside, you are doing valuable and worthy work and maybe, just maybe, you will have a part in preserving this spinning ball of ours. On the downside, you will have to combat ideas held by stubborn people whose belief that the Earth isn't in that much danger will stand in the way of things getting done. Despite all of the scientific evidence, there are still plenty of individuals who don't believe in global warming, or that we are contributing to the hole in the Ozone Layer, or that aluminum cans actually go some place to be recycled.
Don't say "can't"–say "CANS!"
You wouldn't run into a lot of this resistance in certain other scientific avenues, such as a chemist who is attempting to develop a drug that would cure a widespread disease (people across the board are pretty much in favor of curing the sick and dying), but you know that you are doing just as much to ensure the well-being of our species—perhaps even more so—because you are working to give us a planet that we can continue living on. Those chemists can invent as many drugs as they like, but if none of us has any air to breathe in 100 years, it's not going to do us much good.
Our planet is at a crossroads and, as an environmental scientist, you are helping to right the ship. (What a ship is doing on the road is beyond us.) Technology developed within the last century or so has helped (most of) us realize what we are doing to slowly but surely damage the world we live in, and gives us the tools to reverse the trends. Of course, we wouldn't have most of these problems in the first place if it wasn’t for certain aspects of technology, but let’s not quibble.