Certain areas of the historical sciences compete with the witness of the Bible for objective truth regarding origins. There are four key assumptions involved in the customary pursuit of these sciences: (1) the past can be adequately explained without supernatural interventions; (2) the inorganic universe, organic life, and societies have been evolving in a general trend toward higher levels of complexity and organization; (3) the uniform operation of presently observable processes adequately accounts for the physical features of our planet (and the rest of the universe); and (4) the development of our world to its present state has ex tended over vast periods of time.
The concept of long ages for earth history has been difficult to reconcile with the time frame outlined in the Bible. The long-ages viewpoint is bolstered by appeal to events and geologic features that seemingly require more time than the Bible allows. The ice age and the ice caps presently on Greenland and Antarctica are prime examples. However, creationist scientists are confident that many, if not all, of these features can be explained best by a global flood and its aftermath. This article is an effort to describe a model for a rapid development of continental glaciation, based on reasonable assumptions of the climatic consequences of the Genesis 6-8 flood.
For an ice age to occur, cooler temperatures, especially in summer, and a larger supply of moisture are needed at mid and high latitudes than are produced by the present climate. However, the moisture content of the air is directly proportional to the temperature. Cooler temperatures mean less moisture in the air. For example, the interior of Antarctica is one of the driest and coldest regions on earth, receiving only about two inches of precipitation a year. This is a major difficulty in most of the many theories on the origin of the ice age. This difficulty is even more acute for efforts to explain a rapid formation of continental glaciers by present processes.
According to the Flood model developed by many creationist scientists (for example, Whitcomb and Morris in The Genesis Flood), the earth before the Flood was surrounded with a water vapor canopy above the atmosphere (Gen. 1:6, 7). It is presumed that such a canopy would be stable under certain atmospheric conditions and would cause a warm worldwide climate by the green house effect. Not only would the land be warm, but the oceans also would be universally warm as a consequence.
The mechanisms for the Flood are eruption of the "fountains of the great deep" and rain over a period of forty days and nights (chap. 7:11, 12). The implications of the specification that "all the fountains of the great deep burst forth" (R.S.V.) are worldwide violent volcanic explosions, ejecting water, steam, and lava onto the surface until all the pre-Flood land surface was covered by water. (Continental subsidence prob ably also contributed to this process.) One could expect that a large amount of either warm or hot water was involved. These events would produce two unique climatic characteristics immediately fol lowing the Flood. First, the oceans would be relatively warm from top to bottom and from pole to pole. Second, a vast shroud of volcanic dust would re main suspended in the upper atmosphere.
Volcanic dust trapped in the upper atmosphere immediately following the global flood would gradually settle to the ground in about two years in the tropics and over more than 12 years at high latitudes. Volcanic eruptions probably would not cease abruptly at the end of the Flood, but would most likely diminish gradually until the present level of activity was reached. There is evidence for much volcanic activity soon after the Flood—for example, the volcanic cones along the western edge of North America. The decline of post-Flood volcanism may have extended over several hundred years. During this period the dust canopy would have been continuously replenished. Observation associated with recent volcanic eruptions has shown that volcanic dust causes a significant cooling effect by reflecting some of the sun's radiation back to space. Consequently, the dust veil following the Flood would have produced much cooler temperatures than today, particularly over mid- and high-latitude continental regions in summer.
There is another cooling mechanism that would begin operating soon after the Flood. This cooling mechanism would be a widespread, year-round snow surface over many areas of mid- and high-latitude continental regions once the "ice age" started. The reason for this is that snow reflects sunlight back to space, and also insulates the air from the warmer ground.
Warm ocean temperatures at mid and high latitudes following the Flood would have major consequences in providing copious amounts of moisture for snow. The average ocean temperature is now 38 F., which is presumably much cooler than was the case immediately after the Flood. Evaporation from the ocean is directly proportional to the dryness of the air, the wind speed, the instability of the air, and the ocean surface temperature. An ocean at a surface temperature of 75 F. would evaporate more than four times the amount of water than at a surface temperature of 32 F., under the same atmospheric conditions. Therefore a warm ocean would produce the abundant moisture needed for an ice age.
Besides providing abundant moisture, evaporation would also transfer 590 calories of heat from the ocean to the air for every gram of water evaporated. This would be in the form of latent heat, which would be expressed as sensible heat when the water vapor condensed. In addition to this latent heat of water vapor, up to approximately 33 percent more heat would be added to the oceanic air by the direct contact with warmer water. Thus, the air above the oceans at mid and high latitudes would remain fairly warm for a long time following the Flood.
As a result of the cooling of land surfaces and the heating of air over the ocean in mid and high latitudes, cool continents would lie adjacent to warm oceanic air. The greatest horizontal change in temperature would be near the continental shoreline. It is within this zone that storms would develop and move, being steered by upper-level strong winds that would generally blow parallel to the isotherms (lines of equal temperature). The main storm track for the North Atlantic Ocean would be along the East Coasts of North America and Greenland, ending somewhere in the Norwegian Sea or the Arctic Ocean.
In these storms along the East Coast of North America, cold continental air would blow strongly over the warm ocean south of the storm center. This air would be heated and moistened rapidly. The ocean water in contact with the cold air would be cooled and sink, being re placed by warmer water from below and from lower latitudes. The cooler water that sinks would form a layer of cool "bottom water" that would spread out over the ocean bottom, becoming colder and thicker with time. In winter storms, most of the precipitation falls on the colder side of the storm. This would correspond to the cold continents in the post-Flood climate. As the air circulates around the storm center, it will meet the cold continental air to the north and east of the storm center. However, because of the greater density of the cold air, this warmer circulating air would be forced up and over the colder air. This is a potent mechanism for widespread heavy snowfall.
To visualize the possibilities of this situation, I will assume that over a 250- year period one of these East Coast storms develops each week and moves northeast along the coast. These storms would be similar to the northeasters that clobber Eastern North America every winter. The storms soon after the Flood not only would be more frequent than today but also would be much larger with much more moisture. A modern-day northeaster drops about one inch of precipitation along the Eastern Seaboard. Assuming this same conservative snow fall in the post-Flood storms, about 1,200 feet of ice and snow would accumulate in a 250-year period in locations that were cold enough to retain frozen water.
The preceding scenario seems ideal for a rapid development of an ice age. Once the oceans cooled, there no longer would be an abundant supply of moisture, the climate would have changed to much drier, warmer conditions, and the continental glaciers would have begun to recede. Details of quantitative estimates for these processes have been published in the June, 1979, issue of the Creation Research Society Quarterly (2717 Cranbrook Road, Ann Arbor, Michigan 48104).
A net cooling of the oceans would occur primarily where cold continental air blows over warm water in storms. Even though weaker cooling mechanisms would operate over the remainder of the ocean, they would be more than balanced by warming mechanisms. Since the net cooling would occur in a small area of the oceans near the coasts of mid- and high-latitude continental regions by a well-known physical process that occurs today in winter, estimating a length of time and the amount of ice is not as speculative as it first appears. Three fourths of the net cooling of the oceans would be by evaporation, based on modern-day situations. From conservative estimates of the average ocean temperature following the Flood, the area of net cooling, the cooling rate, the horizontal precipitation distribution, and the available moisture for snow and ice from the cooling oceans can be found. Adding this to a small contribution from present-day moisture processes that would be operating at that time, an estimate of the total ice volume for both hemispheres may be calculated. Using the standard ice-covered area assumed for the ice age, an estimate of 1,400 feet may be obtained for the average depth of ice in the Northern Hemisphere. The corresponding estimate for the average depth of ice over Antarctica is 2,300 feet. These values are about one third of the estimates made by glaciation specialists for the maximum thickness of ice-age accumulations. Since many uncertainties are involved in such estimation of non-observable events, the discrepancy is not necessarily significant.
Taking into account the heating and cooling mechanisms from the heat-budget equation for the oceans, and using modern situations that would apply in the post-Flood, oceans could have cooled in approximately 250 years. This would be the length of time to reach maximum glaciation. Scientific evidence indicates that after the oceans cooled and the volcanic dust cleared consider ably, the climate in the Northern Hemisphere would be cooler and drier than it is today. This condition would continue until the ice sheets (except Greenland) melted. Under such circumstances very little snow or ice accumulation would occur on the ice sheets in winter, and summers would produce rapid melting, especially along the southern edge. Using the mountains of Washington and Oregon as an example, it is possible to estimate that during a period of warm, dry weather the continental glaciers might have melted at the rate of about six feet of thickness per year. At this rate, it would take on the order of 250 years to remove the ice sheets. There fore, the total time for a post-Flood ice age might be as little as approximately 500 years.
The present-day ice sheets on Green land and Antarctica can be explained by a 500-year ice age followed by the present climate. The depth of ice at maxi mum accumulation in a rapid ice age would have large horizontal variability. A thicker ice sheet would be found over those areas nearest to the warm oceans and to the main storm tracks. Greenland and Antarctica would be favored by both. Therefore, most of the present volume of ice would likely be accumulated within 500 years following the global flood. The remainder of ice needed to reach present thicknesses can be accumulated by the present climate. The average precipitation today on Greenland and Antarctica is about 12 inches per year and 6 inches per year, respectively, with large horizontal differences. These ice sheets are now approximately in equilibrium, with the amount of ice and snow gained by precipitation balanced by that lost from ice bergs and other processes. However, when the ice sheets were smaller, accumulation would exceed loss. Therefore the present climate over a period of 4,000 years or more is able to produce the present ice thickness, if it was not already attained in a rapid ice age.
The climatic consequences of a global flood have been used to model a post- Flood ice age of possibly only about 500 years' duration. This is but one example of how a universal flood model can be used to explain events and earth structures that under uniformitarian assumptions would require much more time than the Bible allows. We need to keep in mind that there are alternates to certain conclusions proposed within the historical sciences, and that our "faith should not stand in the wisdom of men, but in the power of God" (1 Cor. 2:5).