I've been an environmentalist since before I ever heard of the word. When I was about nine years old, I read about dinosaurs and their extinction and immediately thought that if extinction could happen to the dinosaurs, it could happen to humans (to me!). It became clear to me very early that all elements of the environment are interconnected and that perturbations in one area of the ecosystem could have dire implications for other areas of the ecosystem. We don't know where the tipping point is regarding loss of species, loss of habitat, etc., so to preserve ourselves, our best bet is to preserve all species, something we haven't been doing very well.
So I'm not an environmentalist because I worship nature, as the folks on the right say about environmentalists, but for selfish reasons--reasons that I believe are relevant to (nearly) all humans. (Full disclosure: I do have an appreciation of the beauty and power of nature; I spent a good deal of time in my twenties hiking, camping, and caving in the mountains and deserts of the West). I first learned about global warming in my high school biology class (in the '70s); it was called the Greenhouse Effect and was presented as fact--as far as I know, it wasn't a matter of controversy at the time. It didn't set off my self-preservation instincts--I had no idea that a few degrees could matter (and I think that is still the mindset of many people today). I didn't think about it all until the global warming debate started to make headlines. Then I heard about the scientific consensus that global warming is a result of human activities.
I think many people think that although global warming is happening, it isn't something for them to worry about in their lifetime (again, what do a few degrees matter?). From 350.org:
So far, we’ve experienced about 1 degree (Celsius) of warming, and the impacts are frightening. Glaciers everywhere are melting and disappearing fast, threatening the primary source of clean water for millions of people. Mosquitoes, who like a warmer world, are spreading into lots of new places, and bringing malaria and dengue fever with them. Drought is becoming much more common, making food harder to grow in many places. Sea levels have begun to rise, and scientists warn that they could go up as much as several meters this century. If that happens, many of the world’s cities, island nations, and farmland will be underwater. Meanwhile, the oceans are growing more acidic because of the CO2 they are absorbing, which makes it harder for animals like corals and clams to build their shells and exoskeletons. All around the globe, we’re stacking the deck for extreme weather — like hurricanes, typhoons, blizzards, and droughts — which exacerbates conflicts and security issues in regions that are already strapped for resources.Remember that this is the result of a 1 degree rise in temperature; according to NASA's Earth Observatory, "based on a range of plausible emission scenarios, average surface temperatures could rise between 2°C and 6°C by the end of the 21st century." Even the lower end of the predictions would be disastrous, according to climate scientist James Hansen.
I expect to see climate refugees from within this country (think about the effects of drought in California and much of the West and rising ocean levels in Florida and other places) and skyrocketing food prices as what is now fertile cropland becomes barren wasteland. Yes. I expect to see these things, within my lifetime. So that is where the selfishness comes in. I see suffering ahead for me and those I love, not to mention their descendants. I march in the hope that our collective action will spur the powers that be to take action to limit the effects of global warming. I realize that it is too late to prevent a lot of these effects, but I believe we should do all we can to prevent those we can.
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New York City, Sunday, September 21Clik here to view.

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