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Originally Posted by Intothewind
Ohio: if you would check literature from that time you will see that scientists were already majority predicting global warming(70s).
A few folks presented the idea of global cooling, and the press ate it up...but this idea was never taken very seriously as the evidence was weak. Wikipedia has a whole article on global cooling. In general the media does a very poor job of communication of science, and this could explain a lot of issues we see today
So red herring
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This is a very interesting point that is greatly misunderstood (see Hollywood movies). So let's clarify it. The presentation I have seen from legitimate scientists is not "global" cooling but rather regional cooling sometimes referred to as a "mini ice age".
Here is how this works and it is fascinating. The oceans have global currents that move warm water from the equator up the poles, at the poles the water cools and sinks and then returns to the equator at the bottom of the ocean. It acts like a giant conveyor belt. It moves heat and nutrients. It is critical to the Earth's climate and for life in the ocean.
However, fresh water is less dense than salt water, so even if it is cold it won't sink. (there is a great experiment you could do to prove this to yourself. Get two containers, fill both half full with equal amounts of water and then freeze. Once you have these two large ice cubes fill the other half of the container. In one use fresh water at room temperature. In the other use salt water at room temperature. Then watch (you might want to use time lapse photography). The ice in the fresh water will melt faster than the one in salt water. Why? The salt water is more dense so the ice cube floats up to the top and as it melts it is surrounded with the ice water that can't sink due to convection. In the other container the cold water sinks and the ice stays next to the warmer water and melts quicker.)
So the thought is as the ice is melting rapidly the surface of the ocean in the poles will be ice cold but fresh water that can't sink. This will shut down these currents. As a result we can see the heat in the ocean concentrated in the tropics while the poles are covered with cold, fresh water. If this happens we can measure the decrease in the ocean currents (which we are seeing) and we would expect Europe to get a lot more snow in the winter (which we are also seeing). The only way that this could have a bigger affect than just regional is if it does cause a mini ice age in Europe. Snow and ice reflects more sunlight. I have not seen anyone who is predicting that this effect to the ocean currents will result in global cooling.