The Cause of Ice Ages is Increased Precipitation
The Water Clock Mechanism
It's strange that the cause of ice ages is generally attributed to a mysterious cool-down. There is not a logic for such a mechanism. The cool-down would have to be extreme and sustained. But there is a logic for increased precipitation causing an ice age, and the mechanism is evident in events over the past century.
The usual explanation for ice ages is a cool-down attributed to reduction in solar energy due to variations in the earth's orbit referred to as Milankovich Cycles. A basic problem with that explanation is that the yearly average exposure to the sun is always about the same. Therefore, this concept implies that how the earth is exposed to the sun is more important than average exposure. Such variations are too trivial to explain ice ages. Furthermore, the present ice age cycles have only been occurring for one million years (10 cycles), which points to changing geology.
Sun spots are also blamed for temperature changes. Five years ago, sun spots were so dead that something seemed wrong. No ice age occurred. Now (May 15, 2013) sunspots are at extremely high levels, while record-breaking cold is occurring everywhere.
Oceans are constantly warming due to accumulation of heat which does not easily escape. This graph is a seashell proxy for ocean temperatures showing ice age cycles.
Ocean heat originates with geothermal activity and solar radiation. Geothermal heat is quite significant over thousands of years. The earth's crust is constantly getting thicker due to heat escaping from within the earth.
When terrestrial life began, 543 mya, continental plates were very thin. When they collided, they would stick together rather than going over and under each other, as they do now days, and low hills would form rather than mountains. Prior to dinosaur years, all continental plates were stuck together forming a large landmass called Pangaea. Pangaea was breaking up into continents when the dinosaurs died out 65 mya.
The transfer of heat outward results in high temperatures not far from the earth's surface. Artesian water from 1,800 feet down comes out at about 40°C, which means oceans are surrounded by geothermal heat. Layers of warm water are often found deep within oceans. Convection is not effective over large distances, which results in oceans being complex with layers of varying temperatures. In other words, geothermal heat accumulates for a long time in oceans.
Solar heat also accumulates in oceans. It normally penetrates to a depth of about 10 meters. This depth traps heat in oceans much more than on land.
Because of these sources of accumulating heat, graphs show ocean temperatures increasing constantly during the interglacial warm-ups between ice age cycles. The cycles have been very precisely timed at 100 thousand year intervals for the past 10 cycles. Cool-down occurs for 80 thousand years, and warm-up for 20 thousand years.
Ocean levels drop about 130 meters (400 feet) during ice age cool-downs. It means oceans maintain a high evaporation rate while ice sheets are accumulating and lowering atmospheric temperatures.
As ice sheets form, they would draw moisture out of the air resulting in very low humidity. Low humidity would result in hot and dry conditions beyond the ice sheets. The front edge of the ice sheets would create a dramatic transition from cold to hot in a few kilometers.
In this transition zone, archeologists found an agricultural garden of paradise called Gobekli Tepe in Turkey from 12 thousand years ago. Now the environment has mostly rocks on the surface. A journalist who produced a TV piece on it said humans must have really destroyed their environment. He was standing on glacial till, not human devastation. The agriculture was probably being constantly pushed in front of a moving ice sheet.
This subject is about water vapor, not some mysterious cold. Water vapor was the highly visible cause of the climatic event of the 1980s and 90s. Rainfall increased to a point that the U.S. corn belt moved north and west into sparse grasslands, where cattle and wheat were the usual crops. The increased rainfall was due to the Pacific Ocean heating up. Ice was melting in the Arctic due to warm Pacific Ocean water flowing over the Bering Strait and heating the Alaskan coast. Now droughts are replacing the previous rains, as the Pacific Ocean reverts back to a cooling cycle. The Alaskan coast has gotten as much as 25°F (14°C) colder over the past 5 years due to an absence of warm Pacific Ocean water flowing by. It has been a 5 year cool-down.
These cycles appear to be false starts for the next ice age, which is scheduled to begin at any time. If so, there will have to be enough moisture in the air to create enough snow in the north that it does not melt during the summers. The unmelted snow will reflect away solar radiation resulting in a precipitous cool-down. It will be some time before the Pacific Ocean heats enough to put that much moisture in the air. It will probably be 100 to 400 years before the next ice age begins.
As the Pacific Ocean heats up between ice ages, warm ocean water flows over the Bering Strait and melts Arctic Ice. Heat escapes rapidly from the Arctic area causing a cool-down. When there is enough heat to warm the Arctic area enough to cause more snow in the north than can melt during the summer, the next ice age is triggered in a precipitous manner, because unmelted snow reflects away solar energy.
Warm Pacific Ocean water flowing over the Bering Strait creates a water clock. It takes about the same amount of time between each ice age to warm the Ocean water and raise ocean levels enough to flow over the Bering Strait and warm the Arctic. The water clock has only been occurring for a few short ice age cycles, because movement of tectonic plates created the right conditions for warm ocean water going over the Bering Strait only recently.
This logic cannot be found in collected climatology data, because there are endless variations muddling the subject. The variations are largely due to junk science, which is prevailing now days. Scientists with motives find and synthesize any data which promotes their preconceived ideas, as shown throughout present climatology. To find reality in that mess, it is necessary to look at verifiable events. Long term weather events point to real climate variations.