I Am Not So Sure
Attacking oil industries is considered being cool in certain circles, but I would not be too sure that current climatic changes derive exclusively from the human activities. The multimillennial climatic change cycles exist (for example, the both establishment of the Ice Age 16,000 years ago and its end that was characterized with sufficient warming of the planet), and they pertain rather to geophysics than to technologic activities of humans. I am unaware of underlying mechanism of these cycles (maybe, they have some correlation with solar activity), but serious changes took place many times in the past, when there were either no humans at all, or their usage of carbohydrate fuel was insufficient. Here is some interesting quote
regarding climatic disturbances in the past that were followed by global warming so much intensive that managed to melt billions of cubic miles of ice (I shall not make here all the calculations of energy necessary for this, but I must just mention that specific heat of water is 4.2*10³ J/kg*K), specific density of ice is 900 kg/m³, and specific melting energy of ice I failed to find online, but it is relatively high value as well, if compared to another solid state substances.
When have Ice Ages occurred?
Many glacial advances and retreats have occurred during the last billion years of Earth history. These glaciations are not randomly distributed in time.Instead, they are concentrated into four time intervals. Large, important glaciations occurred during the late Proterozoic (between about800 and 600 million years ago), during the Pennsylvanian and Permian (between about 350 and 250 million years ago), and the late Neogene toQuaternary (the last 4 million years). Somewhat less extensive glaciations occurred during parts of the Ordovician and Silurian (between about 460 and 430 million years ago).
During each of these periods, many glacial advances and retreatsoccurred. For example, over 20 glacial advances and retreats have occurred during the last 2 million years.
If "ice age" is used to refer to long, generally cool, intervals during which glaciers advance and retreat, we are still in one today. Our modern climate represents a very short, warm period between glacial advances.
The main problem is that greenhouse effect has positive feedback: when the average temperature of air rises, the larger amounts of carbon dioxide are being released from the oceans and seas (this gas is normally present there in dissolved state), thus enhancing the processes that cause such a release, and oceanic yield exceeds this stemming from human activities.