I don't know any climate scientists personally, but if I did I'd ask him or her a question I've had ever since I first heard about global warming. My question is this: Assuming that something like the Gaia Theory is correct, what are the chances that our planet is already fighting global warming with or without our assistance?
The Gaia Theory, simply put, states that Earth is capable of regulating itself much like our bodies do, to maintain a balanced system, fight off disease, and keep things like body temperature within an acceptable range. If this is so then, like a home automatic heating and air conditioning system, a kind of thermostat would determine what actions were required to maintain the planet's health and equilibrium.
Scientific study of volcanoes over the last 30 years or so has determined that large eruptions can and do reduce the mean temperature of large areas of the planet, sometimes for many years. If volcanoes are simply random events, each one tuned to its own cycles and rhythms and physical affects, then it's likely that intermittent volcanic activity will have some small impact, but not lasting long enough to be of any real benefit in the fight against global warming.
What if, though, the volcanoes we've been experiencing over the past few decades aren't random, disconnected incidents? What if our living planet is reacting as an organism rather than a big hunk of rock? It gets too hot, the planet has a physical reaction, and turns down the thermostat. Lower thermostat = more volcanoes = cooler planet. We have no way to know, of course, whether this is happening or not, or if it is whether it will be effective, but I'm watching with great interest as each new volcanic eruption is reported and/or predicted.
It may still be too late for us either way. Since the planet's second-hand is gauged in millennia, not only is it unlikely to help us undo the mess we've caused in time for us, but a severe enough reaction to global warming by the planet could very well put us in a long nuclear winter, the old cure-being-worse-than-the-disease.
Kind of like that Twilight Zone episode where everyone is baking to death because the Earth is moving closer to the sun. [spoiler alert!] Turns out the main character was only dreaming that apocalypse, because, in reality, the Earth is moving away from the sun and everyone is freezing to death.