We know that a pail of boiling water set out in sub zero F air will freeze faster than a pail of near freezing water. This is because the boiling water has a convection of hot, humid air that rises over the pail. As the hot, humid air rises in the cold air, it evaporates. The greater the temperature difference, the greater the evaporation. Evaporation works by transferring the heat out of the hot humid air. 

SUPERCOOLED - Liquid water droplets between 0 and -40 degrees Celsius that would freeze immediately if particles were present to start the solidifying process. NOAA

NOAA knows that super cooled water exists in liquid state in normal upper atmosphere to temperatures of -40º Celsius. It may be possible, under extreme conditions, for water to exist in its liquid state to far colder temperatures.

During a hurricane, a low pressure forms near the ground at the eye of the storm. The low pressure becomes lower as the storm becomes stronger. If wind flow all occurred in a linear fashion only, the storm would quickly end as the high pressure would rush in to fill the low pressure. But the hurricane develops in strength, in part, because rising warm, humid air over the ocean creates a convection in the hurricane eye wall. Surrounding lower atmosphere attempts to rush in to fill the base of the rising air column. As the atmosphere passes over the warm water it becomes warm and humid and further fuels the convection. Due in part to the Coriolis Effect the wind rushing in to fill the base of the rising column contributes to the spin. 

As the warm, humid air rises in the center it creates a vacuum (low pressure) relative to the adjacent high pressure areas.  The faster the surrounding, spinning winds blow, the harder it is for the higher pressure air to reach the lower pressure storm center thus the rising air column produces a stronger vacuum near the sea surface.  

A new satellite, called the GERB (for Geostationary Earth Radiation Budget Experiment,) measures the outgoing longwave radiation (OLR) of the Earth.  The most intense places for radiation to leave the Earth appear to be in hurricanes or typhoons as can be seen in figure 1 below.

Figure 1: Clear-sky Outgoing Longwave Radiation (OLR)

Hyper Hurricanes Discovery.com

The radar generated picture of a Hurricane Bonnie dramatically illustrates how these rising convections with thermal momentum can pierce the upper atmosphere.  It would appear from the image that the reason rising convections don't normally pierce all the way through the stratosphere is due to the movement of the hurricane and the thickness of the atmosphere nearer the equator.  However, in the super storm scenario envisioned at the turning point between rapid global warming and rapid global cooling, the hurricane will form near 60º latitude or greater and remain stationary.  This allows the rising convection to continue increasing to higher altitude and to do so in a much shorter atmospheric height.  

Near the equator, where most hurricanes of today form, the surrounding water is warm in most directions. However, in the North Atlantic at the ends of the Atlantic Conveyor, the warm Gulf Stream would be fed into a storm much like a steady flow of coal is fed into a furnace. Where the super storms occur the storm system remains stationary and the fuel is fed into the eye of the storm. As the storm feeds on the warm water, it also creates a draw by sucking air over the Gulf Stream and causes the currents to flow faster into the eye of the storm. At this point the Atlantic Conveyor is speeding up in the North Atlantic, but the southern latitudes cannot handle the faster return of cold salty water and the deep cold current begins to break up under the ocean. Any submarines that happen to be under the North Atlantic at that time will certainly be lost to extreme underwater ocean currents.

Extreme convection occurs during a super storm over Labrador and the Norwegian Sea.  This extreme convection causes extreme evaporation, which causes extreme cooling of the surrounding atmosphere. The heat from this extreme evaporation is shot straight out into space through the stratosphere, explaining how the Earth rapidly loses heat. This heat that has gone into space is being shot out much like an air conditioner pumps heat out of a room and dumps the warmer air outside of a building. The heat escaping through rising convection of an extreme hurricane is lost heat and cannot be soon replaced.

As the atmosphere near the tropopause rapidly cools it  could form liquefied air. This liquefied air would build up in large pools due to the extreme updraft of the storm, until it finally spills toward the ground in huge quantities. This liquefied air instantly cools the copious amounts of rain falling from the sky as well as the heavily flooded surface below.

Since this event is occurring during the peak of global warming, there are large reservoirs of heated ocean water and heated lower atmosphere to feed this system for days and even weeks. Even while the warm waters are feeding the system, huge quantities of ice are falling over the outer areas of land causing rapid ice accumulations over a mile deep over Labrador and the Norwegian Sea. The ice immediately pushes down on the earth causing huge earthquakes. The buckling under the area of the St. Lawrence river provides the best channel for the new ice to flow through, and much of the ice flows in this direction causing a long fold in the Earth's crust, just as the record shows.

And just as the record shows, the ice flows mostly from a central spot over Labrador, Canada. Other centralized spots could occur from other induced storms. Just on the other side of Hudson Bay, Canada is another place where ice accumulated in the Younger Dryas ice advance. Also, there is a minor ice accumulation just east of the Canadian Rockies. But the Canadian Rockies flow is probably due to subsequent cooling of the Northern Hemisphere and the layering of many years of snowfall.

During the super storm, much of the heat that had been accumulated during the previous period of global warming has been ejected into space through the eye of the hurricanes. There is no other explanation offered by science to explain the sudden disappearance of atmospheric and oceanic heat. Heat has energy, and that energy must go some place. You cannot suddenly produce a cold planet without accounting for the sudden loss of energy. In other words, high temperatures do not directly make ice cubes or snowflakes. There has to be some mechanism for pumping the heat out of the atmosphere and disposing of it in order to cool the temperature of the planet as much as it has cooled during the Younger Dryas period and previous periods of rapid cooling.

The shutdown of the Atlantic Conveyor would truly cool Europe. But if the Atlantic Conveyor were the only cause of a cool Europe, then the heat that would normally warm Europe must still exist somewhere else on the planet. It cannot suddenly disappear just because the ocean currents change. In the case of thermohaline circulation break down, there is merely a redistribution of heat. There is no mechanism in a changing thermohaline circulation that could cause heat to vanish from the surface of the planet as quickly as the historical climate records show.

The only mechanism that I have found that could physically remove heat from the earth's surface is a hurricane.

BTW, even today, hurricanes are pumping heat into space. It could very well be the explanation for why the planet isn't overheating to the extent the climate models are predicting. Hurricanes, typhoons, and Nor'easters are nature's natural air conditioners for regulating Earth's temperature by physically expelling excess heat into space when the planet gets too warm.  It's when the air conditioning machinery works too well and doesn't have a thermostat to turn itself off that the planet experiences the extreme cooling events.