Given the strong pattern of global warming and cooling we see in long term ice core records (included below) it seems inevitable that the Earth is about to return to it's more common (at least in recent times) ice age conditions.
Given the likely strength of the natural forces involved in producing this cycle, is it even possible for the actions of humans to have any hope of altering the natural cycle?
Hare are some opinions from Woods Hole Oceanographic Institute
Excerpt:
"Are We on the Brink of a 'New Little Ice Age?'
By Terrence Joyce, Senior Scientist, Physical Oceanography and
Lloyd Keigwin, Senior Scientist, Geology & Geophysics
When most of us think about Ice Ages, we imagine a slow transition into a colder climate on long time scales. Indeed, studies of the past million years indicate a repeatable cycle of Earth’s climate going from warm periods (“interglacial”, as we are experiencing now) to glacial conditions.
The period of these shifts are related to changes in the tilt of Earth’s rotational axis (41,000 years), changes in the orientation of Earth’s elliptical orbit around the sun, called the “precession of the equinoxes” (23,000 years), and to changes in the shape (more round or less round) of the elliptical orbit (100,000 years). The theory that orbital shifts caused the waxing and waning of ice ages was first pointed out by James Croll in the 19th Century and developed more fully by Milutin Milankovitch in 1938.
Undefined Ice age conditions generally occur when all of the above conspire to create a minimum of summer sunlight on the arctic regions of the earth, although the Ice Age cycle is global in nature and occurs in phase in both hemispheres. It profoundly affects distribution of ice over lands and ocean, atmospheric temperatures and circulation, and ocean temperatures and circulation at the surface and at great depth.
Since the end of the present interglacial and the slow march to the next Ice Age may be several millennia away, why should we care? In fact, won’t the build-up of carbon dioxide (CO²) and other greenhouse gasses possibly ameliorate future changes?... "