The Photon Current - 8

Fig. 1 WOD Layers

In the past I have built a database using the World Ocean Database (WOD), but I have in recent years presented that data in a "pelagic depths" average format.

Today, I want to clear up the meaning of the "Hadopelagic" (a.k.a. "Hadal Zone") in terms of the ocean depths involved:

"In most areas, the ocean floor lies 4,000 to 6,000 meters (13,000 to 20,000 feet) below the surface, but deep ocean trenches can extend this depth to 11,000 meters (36,000 feet). The region extending from 6,000 to 11,000 meters is called the hadal, or hadalpelagic, zone after Hades, the Greek god of the underworld. This zone occurs only in trenches; combined across all oceans, they make up an area about the size of Australia."

(Woods Hole Oceanographic Institution, emphasis added; accord: Wikipedia, NOAA). That is not the same as the WOD.

The WOD manual lists 33 standard depth levels which have quality control (maximum, minimum) values for temperature and salinity (I used only those depths because of the quality control values):

"APPENDIX 11. ACCEPTABLE RANGES OF OBSERVED VARIABLES AS A FUNCTION OF DEPTH, BY BASIN

The range values provided has range values for temperature, salinity ... The range values in the tables are used to help identify the most obvious questionable values for these variables. Please note that ranges are given on 33 standard levels (+ one for depths deeper than 5500 m)."

(WOD manual 2013, Appendix 11.1 - 11.2, p. 132-137).

The last level spans 5501 meters deep down to the bottom of the ocean.

In other words, there is a 500 meter variance (6,000 - 5,500 - 500) between the "Hado-" a.k.a. "Hadal-" pelagic depth levels and those quality controlled WOD depth levels.

I have used the average of WOD depth values then converted those into pelagic depth levels in past posts.

So, that 500 meter variation has resulted in 500 meters of the Hadopelagic being included in last quality controlled depth layer WOD  specification.

There was some impact on the calculations at the depths where the two were combined used in terms of averaging.

So, to resolve the 'conflict' from now on I am resorting to the WOD depth levels in graphs instead of the using the pelagic depth values.

This makes the graphs very detailed (33 lines per graph instead of only 5 lines), but once a reader gets used to it there is more detail in the new format.

It also tells a more comprehensive story about what is happening "down under".

Today's graphs are presented in WOD layer format (Fig. 1), including the new depth-level format (Appendix WOD D-1, Appendix WOD D-2, Appendix WOD D-3).

The line-color legend appears at the top of each appendix.

Remember that this series is about currents/streams of ocean heat in the form of infrared (IR) photons.

They travel from 'warmer' atom/molecules (higher IR energy level) to 'cooler' atom/molecules (lower IR energy levels) pursuant to the Second Law of Thermodynamics.

The lines on the graphs represent in situ measurements taken by researchers then sent to the WOD for the use of oceanographers and other interested members of the public.

The next post in this series is here, the previous post in this series is here.

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