Hurricane Season Begins

Jeff Masters has a rundown on the prospects for early-season hurricanes. Summary: not so much. The water’s too cool and the wind shear too high. Probably not much serious before August. I found this particularly interesting (I hadn’t previously been aware of it):

It’s not just the SSTs [Sea Surface Temperatures–rs] that are important for hurricanes, it’s also the total amount of heat in the ocean to a depth of about 150 meters. Hurricanes stir up water from down deep due to their high winds, so a shallow layer of warm water isn’t as beneficial to a hurricane as a deep one. The Tropical Cyclone Heat Potential (TCHP, Figure 3) is a measure of this total heat content. A high TCHP over 80 is very beneficial to rapid intensification. As we can see, the heat energy available in the tropical Atlantic has declined steadily since 2005, when the highest SSTs ever measured in the tropical Atlantic occurred. I expect that the TCHP will continue to remain well below 2005 levels this year, so we should not see any intense hurricanes in July, like we saw that year.

A lot of the Warm Mongers were saying (ignorantly) that 2005 was the beginning of a trend of more and more intense hurricanes, brought on by You Know What. Well, with the current cooling going on, so much for that.

[Update a few minutes later]

I should add that my understanding of the current thinking on the subject of warming and hurricanes is that there will actually be fewer hurricanes forming in a warmer world, because there will be more wind shear that prevents them from doing so. On the other hand, if they do manage to get it together, they will be more intense, due to warmer ocean waters.

3 thoughts on “Hurricane Season Begins”

  1. Speaking as an engineer…

    Hurricanes, tornados, and lesser weather phenomenon, are all driven by temperature differentials. It is also necessary for the hot part to be hot moreso than the cold part be cold.

    When the earth warms, it warms moreso in cold latitudes, decreasing the differential. This can be somewhat offset by the increased carrying capacity of the normally hot air getting hotter.

    However, if we are 85 at the equator and 75 at the poles, the engine is slow, though there may be a lot of rain (the air can hold more moisture).

    On the other hand, when we go from generally warm to sudden cooling, as we have, you get fewer hurricanes, lower intensities, and more rain – temporarily, as the water drops out.

    2005 was the peak for hurricanes, for now, because we had reached a good metastable point between too hot and too cool.

    We are getting a lot of tornados this year because we lost almost a degree C between last fall and now. Once the energy lose averages out more, their frequency and intensity will lessen.

    Wetter this year, with a colder winter, and spring to come, but no ice.

    yet.

  2. Hurricanes, unlike like baroclinic systems, aren’t driven by horizontal temperature gradients. They’re driven by vertical temperature (and humidity) gradients. Or so I understand.

  3. One could even draw parallels to the planets in our solar system. The further out you go, the colder the respective planet gets and the higher the average wind velocities measured. Neptune has the highest wind velocities measured out of any of the planets. The thinking is that the colder temperatures reduce the amount of turbulence which impedes overall velocity. While Neptune’s great dark spots, large storm vortices, aren’t as big as Jupiter’s great red spot they are still quite large and develop then disappear in shorter intervals when compared to Jupiter. Using HST we have seen several massive dark spots come and go on Neptune, yet Jupiter’s storms tend to take several years to develop and then persist for much longer. Both Neptune and Jupiter both produce about twice the amount of heat internally then what they receive directly from the Sun.

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