From a scientific standpoint, you pretty much can be certain that even in the unlikely event that man is "causing" global warming, no one will ever be able to prove it. Here's why...
1. The Earth has been getting warmer since the last Ice Age ended about 12,000 years ago. From a climatological standpoint, the mesoscale baseline is: global warming.
2. Based on everything we've ever learned from archaelogy, this warming trend wasn't caused by man-made greenhouse gases.
3. We don't know now (and may not ever) what caused the warming trend.
- Was it a bunch of volcanoes?
- Solar weather fluctuates too, something we're only beginning to understand... Did the Sun get hotter?
- Was it something else?
4. Although the overall trend is warmer, there are still other flucuations up and down along that gradually rising line.
- About 4,200 years ago ancient civilizations in Egypt, Mesopotamia, the Indus Valley (Mohenjo-Daro), and elsewhere suffered catastrophic decline or disappeared. Best evidence now is an intercontinental famine caused by a planet-wide drought. But eventually that passed.
- For several centuries before the glory years of the Vikings Scandinavia experienced milder winters and longer growing seasons. This led to the population explosion that enabled their expansion. The decline of the Vikings coincides with the cooling of the Nordic regions.
- Which leads us to the Little Ice Age, which lasted in Europe from the 1300s to the 1600s. Glaciers advanced and growing seasons were shorter. And that too, passed.... All without an industrial civilization to change the global climate.
5. So not only is the overall climatological baseline over the last 12 millenia gradually warmer, without human intervention, there are also fluctuations along that baseline that demonstrate greater variance over longer periods than what the Chicken Littles claim they're observing now. And there's not even a consensus on that.
In science there's a burden of proof, and the global warming crowd hasn't met an ounce of it.
Hence, we can safely dismiss them... out of hand
