@JohnyMac, I really don't think it matters any more what is causing climate change - but you can tell climate is changing.
so during the time man has been writing about things - roughly 6,000 to 10,000 years - we know that we have been affecting the planet we live on. agriculture, animal husbandry, burning wood, burning coal, burning petro-chemicals, paving over the prairie, changing the critter mix on the planet (pushing some out and growing lots or others) - these have affects you can see, feel, smell and measure. The picture you posted illustrates that. the smog is created by human activity. I remember the pics of Los Angeles from my younger days. many cities have smog when the wind and weather conditions are right. The smog is always there but you can only see it when the weather conditions are right.
question, where does the smog go? it isn't converted back into oil. Only tiny amounts precipitate out. so where does it go? some is absorbed by plants or the ocean but the rest of it stays in the atmosphere. this can and has been measured - over time and for years. So lets multiply the human input into our climate system by the length of time humans have been at work - 6,000 to 10,000+ years and scale this with the number of humans and amount of gasses we pump into our atmosphere. we also know that the climate is affected by several inputs, volcanoes solar radiation and even our planets orbital mechanics feed into this.
so are you willing to say that as human numbers increase and the measurable affect we cause - which can and has been measured - that we couldn't change or amplify the changes going on in our climate? One last item, all things live within narrow parameters. too hot or too cold and life can't survive. too much water or too little water and life can't survive. (this could go on for a while but i'll stop here) I would suggest that we keep our biosphere withing limits we can survive in.
My point is this;
climate is changing. It is changing in ways that mimic historical epochs in which humans weren't alive.
to use an analogy, if a car looses its brakes while going down hill you might want to take your foot off the gas maybe even steer the car into the ditch so you don't go over a cliff. the hill may be the other inputs into our climate but the gas pedal is under the control of us humans.
we can argue how much of the climate change is caused by external factors and how much is caused by man but to use another analogy, Why would we humans want to bale water into the Titanic?
