re: Current idea that cold is from global warming fundamentally flawed?

The theory of warming triggering major cooling has to do with two interrelated parts of the earth's climatic system: salinity and heat flow in the atlantic ocean.

The theory revolves around what is known as the north atlantic conveyer system (of which the gulf stream is a part) which consists of ocean currents that take warm air from the tropics north towards Iceland which then sinks as it cools and flows back south. This helps to keep temperatures more mild in the northern Europe and Canada than they would be otherwise. What allows this to happen is that salinity varies both in temperature and depth and has a huge effect on buoyancy (for example, you are far more buoyant in the Dead Sea than in a fresh water lake). This allows the cold water to sink beneath the warm and flow south.

The theory as related to global warming states that as temperatures across the world increase, more arctic ice will melt, adding more freshwater to the north Atlantic Ocean. This change in salinity will reach a tipping point where the cold water will no longer be able to sink beneath the warm water mass and flow south, causing the conveyor to grind to a halt.

Without this flow of energy, Europe and North America get colder and wetter while the tropics get hotter and dryer. This has been observed at times throughout the ice ages.

The fear is that man is contributing to warming, therefor accelerating the process. Personally, i think man-driven agw is hogwash thanks to my knowledge of climate and modeling techniques.