Re the view that humans are making the Earth less habitable for HUMANS (and many other creatures).
This is my jeremiad: The Earth itself will survive, of course, but in an altered state. The question then becomes what will happen to possibly billions of humans in coming decades, as the U.N. projects in its middle projection that the Earth will have 9.1 billion humans by 2050, an increase of 2.5 billion over today. For example, with global climate change, what will ensue--what rapid human changes will need to made--if the agricultural zones of the central Plains in the U.S. shift northward hundreds of miles toward and into Canada? How many trillions of dollars would be needed to make that adjustment, an adjustment to an area that is one of the principal breadbaskets of the world?
Yes, the world is always in flux and climate is no exception. Scientists believe we are in an interglacial period, but the overwhelming consensus is that the current rapid changes are anthropogenic (human-caused) in origin.
Not abusing the Earth? Mountaintop removal in the coalfields of Appalachia where I worked as a strip-mine inspector; the mass of plastic the size of Texas floating in the Pacific Ocean; the great majority of rivers in China that are terribly polluted--I'd say these are just a few examples of the human destruction of life-systems of Earth.
Sure, global climate change might benefit the five countries bordering the Arctic Ocean, as it is now projected that the Arctic Ocean will be completely ice-free by 2070, and those countries could explore for what might be 25% of the world's reserves of oil and gas. At the same time, of course, the rise in the eustatic level (sea level) would also cause some massive readjustments along coastlines of the planet, where so many people (including me) now live.
One huge change looming just over the horizon is the approach of peak oil, when the production of petroleum that has for so long been increasing, reaches the point of decreasing production. Even though at that tipping point there would still be a great deal of oil in the pipeline, prices would begin a rapid spiral upwards. Sure, there would be lots of oil, but priced beyond what our economy could easily use. Again, massive changes would ensue, too fast to adjust to without gargantuan disruption to life as we are used to living it.
Yes, Earth will survive, but what is the fate of life as we know it? Jerrod Diamond, a historical geographer at UCLA, writing in Collapse, his study of the causes of collapse of past civilizations, outlined several reasons for civilizational failure. They include civilizations who saw the collapse coming, but were not able to make necessary changes in time. I think this is where we are at this point: seeing, but not believing enough, or partly paralyzed into inaction. We'll see. Unless we forthrightly begin practicing in our public policies the precautionary principle, then we react too late to the changes. It WILL be interesting.