Atlantic basin temperature comparisons, 2005 vs 2004

[x-y-no]

Surface temperature this year:


vs same date last year:


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26 degree isotherm depth this year:


last year:


----

Depth of the 20 degree isotherm this year:



vs. the same date last year:


(these figures come from the NOAA upper ocean heat content site http://www.aoml.noaa.gov/phod/cyclone/data/)

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If, as one member claimed in another thread, the high sea-surface temperatures observed across the basin are due to lower winds resulting in a lack of vertical mixing, one would expect to see a shallower depth for the isotherms. In fact, the opposite is evident across the entire basin.

No, the simple fact is that there is substantially more heat in the entire mixed layer across the entire basin than there was on this date last year.

Jan

[vbhoutex]

Thanks Jan for that post. It is quite evident that the water is just getting plain hot and not just at the surface. This could indeed turn out to be a very active and interesting year in the tropics(as if it hasn't already started out that way with Adrian).

[cycloneye]

Very revealing grafics that show how beneath the surface things are doing and do not bold well for many in the basin.

[cyclonaut]

Yes this is very revealing & quite startling actually!

If this situation continues to unfold the way it is,it is going to be a interesting & to be honest,a dangerous season ahead.

[x-y-no]

Some more interesting figures to compare:

The "Tropical Cyclone Heat Potential" (THCP) is a measure of the energy available in the surface layer for fueling tropical cyclones.

(sorry about the size of the first one, they've changed their format)

TCHP for yesterday:



Same date last year:



End of June last year:



End of July last year:



End of August last year:



As you can see, it's much warmer than it was even at the end of June last year. And while the western Caribbean and Gulf are cooler than they were by the end of July, the eastern Caribbean and the area east of the islands area are warmer than they were even at the peak of last year's season.

Jan

[SkeetoBite]

Animated SST comparison - May 26, 2004 to May 26, 2005

[LAwxrgal]

That water is boiling Seems to be one straight line from the Caribbean clear to the Gulf.

[canegrl04]

This is quite alarming. If the shear in the Atlantic is relatively low this season, alot of people in the GOM and along the Easat coast will be in for alot of hurt

[gatorcane]

With the water temperatures being warmer than last year..IF we have the same or less shear across the Atlantic...we'll see more tropical systems...I wouldn't be surprised if we surpassed last year

[senorpepr]

Here's an idea that has been running through my mind lately: with the ITCZ further north than normal and the water temperatures being what they are, I wonder what the conditions through Northern Africa are like. Are they seeing lower-than-normal rainfall which would allow for more duststorms to exist? If so, the SAL will possibly negative the effects of the warmer water. On the flip side, if the rainfall rate is higher-than-normal......

[cycloneye]

Here's an idea that has been running through my mind lately: with the ITCZ further north than normal and the water temperatures being what they are, I wonder what the conditions through Northern Africa are like. Are they seeing lower-than-normal rainfall which would allow for more duststorms to exist? If so, the SAL will possibly negative the effects of the warmer water. On the flip side, if the rainfall rate is higher-than-normal......

Interesting thought Mike.

[Cookiely]

Here's an idea that has been running through my mind lately: with the ITCZ further north than normal and the water temperatures being what they are, I wonder what the conditions through Northern Africa are like. Are they seeing lower-than-normal rainfall which would allow for more duststorms to exist? If so, the SAL will possibly negative the effects of the warmer water. On the flip side, if the rainfall rate is higher-than-normal......

Did you see what Dr. Gray reported about the West African rainfall?
2 Earlier 1 June Statistical Hurricane Forecast Scheme
Our original early June seasonal hurricane forecast scheme was developed in the early 1990s and demonstrated significant hindcast skill for the period of 1950-1991 (Gray et al. 1994). This scheme included measurements of West African rainfall as an important forecast input.

Since the observed shift of Atlantic Ocean SST patterns in 1995 [and the implied increase in the strength of the Atlantic Thermohaline Circulation (THC)], our original 1 June forecast scheme (1994) has consistently underpredicted Atlantic basin hurricane activity. Our earlier 1 June statistical scheme used West African rainfall data as an important predictor. We do not understand why, but the previously observed (1950-1994) strong association between West Africa rainfall and Atlantic hurricanes has not been reliable since 1994. We have lost confidence in the previous 1 June statistical forecast scheme compared to our newly developed one. We have thus decided to discontinue our earliest 1 June forecast scheme.

Over the past couple of years, we have been using an updated statistical scheme that utilized NOAA/NCEP reanalysis data. However, this scheme used mostly data from the previous fall and winter, and therefore we have recently developed a new early June scheme that makes use of mostly spring data.

[senorpepr]

Here's an idea that has been running through my mind lately: with the ITCZ further north than normal and the water temperatures being what they are, I wonder what the conditions through Northern Africa are like. Are they seeing lower-than-normal rainfall which would allow for more duststorms to exist? If so, the SAL will possibly negative the effects of the warmer water. On the flip side, if the rainfall rate is higher-than-normal......

Did you see what Dr. Gray reported about the West African rainfall?
2 Earlier 1 June Statistical Hurricane Forecast Scheme
Our original early June seasonal hurricane forecast scheme was developed in the early 1990s and demonstrated significant hindcast skill for the period of 1950-1991 (Gray et al. 1994). This scheme included measurements of West African rainfall as an important forecast input.

Since the observed shift of Atlantic Ocean SST patterns in 1995 [and the implied increase in the strength of the Atlantic Thermohaline Circulation (THC)], our original 1 June forecast scheme (1994) has consistently underpredicted Atlantic basin hurricane activity. Our earlier 1 June statistical scheme used West African rainfall data as an important predictor. We do not understand why, but the previously observed (1950-1994) strong association between West Africa rainfall and Atlantic hurricanes has not been reliable since 1994. We have lost confidence in the previous 1 June statistical forecast scheme compared to our newly developed one. We have thus decided to discontinue our earliest 1 June forecast scheme.

Over the past couple of years, we have been using an updated statistical scheme that utilized NOAA/NCEP reanalysis data. However, this scheme used mostly data from the previous fall and winter, and therefore we have recently developed a new early June scheme that makes use of mostly spring data.

No, I hadn't read that yet. I really haven't had a chance to sit down and read the whole report yet. However, his comments are very interesting. Although, he points out West Africa rainfall -- I wonder what the results would be if he factored in more regions across the Saharan Desert as well as Central Africa. Of course, with that is the lack of reliable observations throughout the continent.

Either way, my thoughts are if one thing could make this season not as favorable as most are saying, it would be the affects of the SAL. This is based off of the post 1994 era of above normal activity where a good wave would begin to take shape, only to have the SAL tear it apart. The remnants would then wait a few days to get away from the SAL and then redevelop. What that leads me to think, if the SAL is decreased as compared to previous years, this should allow systems to develop a bit earlier therefore allowing more time for dynamic cyclogenesis into a strong hurricane, which would then add to the possibility for increased hurricane and major hurricane landfall potential.

[dhweather]

Jan, great graphics, thanks for posting them.

Quite obviously, the tropics are very warm - scary potential this year.


David