Oceanic Heat Content

[Dave R]

Can someone explain to me the difference between oceanic heat content and the ocean temperature? Now, I understand that a hurricane needs warm water to a certain depth, but what I don't understand is why shallow water does not contain the oceanic heat content as deeper water. When the water is deep, doesn't upwelling become a factor as the storm churns up the cooler water from deep below the surface? With shallow water, there is no deep cool water to bring to the surface.

[wxmann_91]

Can someone explain to me the difference between oceanic heat content and the ocean temperature? Now, I understand that a hurricane needs warm water to a certain depth, but what I don't understand is why shallow water does not contain the oceanic heat content as deeper water. When the water is deep, doesn't upwelling become a factor as the storm churns up the cooler water from deep below the surface? With shallow water, there is no deep cool water to bring to the surface.

Suggestion: post this in the Talkin' Tropics forum.

Yes, oceanic heat content is a measurement of the depth of warm water. The greater the oceanic heat content, the less upwelling there will be from a hurricane, and thus, the hurricane has a better chance of getting stronger. The problem is that with low oceanic heat content, all the water will be upwelled even before the eye reaches a certain area, thus starving a hurricane. Low oceanic heat content cancels the effect of even the warmest SST's.

Shallow waters obviously have shallower depths of warm water, so coastal areas usually have less oceanic heat content.

Upwelling is the bringing of cooler waters deep beneath the surface to the surface, but with high oceanic heat content the waters are warm throughout the ocean, and the upwelling process would take longer. (Upwelling in fact takes some time, and if a hurricane is moving fast enough and the heat content high enough waters will not be upwelled.)

[Dave R]

Thanks for the explanation. Makes sense.