I'm neither "Left Wing," nor a Treehugger, but......
It's fairly clear these things are happening. Image here is a CGI composite taken from satellite imagery between 1979 and 2007. Yes, I know the photo could easily have been edited for dramatic impact. The original satellite photographs can still be found that show this as a fairly accurate representation, however.
Funny thing about our environment. Temperatures dip and change according to so many factors - human involvement included - that it becomes very difficult to point to one single agent and say "THIS is the cause." Our orbit does not stay PERFECTLY circular, and our polar wobble can have slight variations. Solar winds and intensity play a role. Plate tectonics, of all things, can be a factoralso. And of course, of course....man-made CO2 production as well as CFCs and methane (I blame the cows.....) DO have a part to play in this as well. You'd have to have your head seriously in the sand to claim that our actions play no part in this at all.
If you set that all aside, however, you come back to the main point about our weather: We can't control it. For instance, the earth is supposed to be going through a long-term warming trend right now -- we're in between ice ages, as some people like to say. However, a study was just published last month that indicates the globe is entering a
"mini-cooldown period" for the next thirty years! They didn't deny the overall warming trend, they just said it was going to be broken by a short period of cooler temperatures.
I'm about as middle-of-the-road as you can get. I don't embrace a lot of values that are considered "leftist," but I do believe that our involvement in this planet can contribute to climate change....for better or worse. When all is said and done, the best things we can do are the little things. Turn off the lights when you're gone. Don't run the faucet while you're brushing your teeth. Try to save gas and schedule one large trip, instead of multiple little trips, to the store.
Don't buy a Prius. Huge carbon footprint, or so I hear. But...don't buy a Hummer unless you need it, either. ;-)
And finally, if you get tired of shoveling that snow in the dead of winter, come on down here to Florida for a visit. Have a beer with me on the east coast, then head on over to the gulf side and catch up with Florida Joe. If we're not out fishing or sunning on the beach, that is.........