The Proceedings of the Eighth International Conference on Creationism (2018)

As the air gains speed from the pressure gradient force, it is turned to the east by the Coriolis effect until the winds blow perpendicular to the pressure gradient force. Winds where the Coriolis effect is equal and opposite to the pressure gradient force are called geostrophic winds. At the polar front, warm and cold air masses are in close proximity, thus resulting in a strong pressure gradient force. As a result, the geostrophic winds achieve high velocities and are called the jet stream. If the temperature contrast between air masses on each side of the polar front is reduced, the pressure gradient high in the troposphere is weaker resulting in weaker winds in the jet stream. Precipitation patterns are influenced by this three cell global circulation pattern. Due to the Coriolis effect surface winds in the tropics are primarily from the east and are called the trade winds. In the mid-latitudes winds shift direction and are called the westerlies and in the polar cell they switch back to easterlies. Since oceans are a ready source of water vapor, it seems reasonable that higher rates of precipitation should occur where global winds drive humid air over continents. In the mid-latitudes Pacific air pushed up against the mountain ranges of the western United States and Canada results in high precipitation rates as illustrated in Figure 3. It is expected that the same effect should be seen on the east coast of Canada due to the polar circulation; however, the amount of water vapor in the air is smaller due to the colder North Atlantic water temperatures. There is another thermal circulation that must be considered when dealing with warm oceans and cold continents. Although the global circulation pattern places a band of low pressure around the globe at a latitude near 60˚, the difference in ocean/land temperatures superimposes another thermal circulation on the picture. During the summer the land is warmer than the ocean and a low pressure system resides over the land. This enhances the low pressure at the polar front and pulls humid air from the ocean over the land. However, in the winter this circulation is weakened or reversed due to the oceans being warmer than the land. The stronger the land/ocean temperature contrast the stronger the circulation and the stronger the precipitation pattern. This is clearly seen in the warm ocean simulations of Spelman (1996) and Gollmer (2013) as illustrated in Figure 4. Since the oceans are warmer than the continents in January, the rising portion of the thermal circulation is over the water, which is also where the precipitation falls. The superposition of the global thermal circulation and continent/ ocean thermal circulation provides the big picture, which is the focus of this paper. However, it may be that additional factors will prove significant and can be the focus of future research. First, the three cell model described previously is not static, but shifts with the seasons. Although the ITCZ resides near the equator, it will shift into the Northern Hemisphere during the spring and summer months. Likewise, the location of the jet stream will move further north during the summer and further south during the winter. This transition results in volatile weather east of the Rockies in the United States during the spring and fall. Second, storm tracks are influenced by large mountain ranges, contrast in land/ocean surface roughness and location of the sub-tropical jet (a weaker jet stream occurring at the interface of the Hadley and Ferrel cells). These factors combine to situate a storm track along the eastern coast of the United States (Brayshaw et al., 2009). It could be that this storm track could draw humid air into Southern Canada and the Great Lakes region from the Atlantic Ocean. DESCRIPTION OF THE MODELAND MODEL SIMULATIONS GCMs are essentially low resolution weather models used to Gollmer ◀ Post-Flood Ice Age precipitation ▶ 2018 ICC 698 Figure 3. Precipitation and surface winds during January for the North American Continent demonstrate the connection between these two parameters. As westerly winds in the Ferrel cell move humid ocean air towards the west coast of the continent, there is precipitation that penetrates to the coastal mountains and even to the Rockies. In the polar cell, which is dominated by easterly winds, there is coastal precipitation in Labrador, New Foundland and Greenland, but not to the extent observed on the west coast.