Saturday, December 29, 2018

The Ghost Plumes - 5

I. Background

In this series I have written about the difficulty of calculating plume volume:
"Thus, at this time I am not able to report on any specific tidewater glacier's plume width or, therefore, any specific glacier's plume volume.

At this point I am left with the meta-level computations which I am blogging about at this time." - The Ghost Plumes - 2
"That melting of the tidewater glaciers is taking place is not debatable, however, the amount of melt water in hypothetical thermodynamic plumes ... is quite debatable since the concept is "embryonic" at this point ... The object of the use of that paper's ["by R. Bindschadler et al."] conclusions is to determine a ball-park figure for thermodynamic plume flow volume along the world's longest wall of ice ..." - The Ghost Plumes - 4
(etc., etc.). The experimental numbers I have calculated by using the data of that paper were way too high, so I changed them (explained below).

Assuming the data and calculations in that paper ["by R. Bindschadler et al."]  are correct in substantial degree, I changed plume flow timespan.

NOTE that the Appendices (A, B, C, D, E, and F) now contain values required to raise sea level by 1 mm in each Area and each zone within each Area.

Those figures are quite accurate and show that this could be a significant undertaking.

This approach also explains why I am interested in being able to calculate the actual ghost plume melt water volume with the best precision we can derive.

But, until I can find the sea level and changes in it caused by tides around Antarctica, I can't calculate the vertical distance from the grounding line to the mean sea level, i.e. the middle level between high and low tides.

I need that to zero in on actual plume flow volume.

II. Focus

The current idealized plume height value (pH) is obviously not the real world value because not all grounding lines are at the same depth.

Even glaciers that are next to each other can have significantly different grounding line depths (A Tale of Two Glaciers).

Furthermore, the fact that the plume height (pH) varies from year to year in the Appendices is due to at least two factors:
1) that value is calculated from in situ measurements taken in a zone at different times, in different years, at different depths, by different research crews, in different ice, weather, and ocean conditions,

2) those in situ values are only used if the TEOS-10 toolkit indicates (using "CT", "SA", and "P" values calculated from the in situ measurements) that an ice face section will be melted by those conditions.
Thus, this is a beginning point like "A New Mersenne Prime Discovery" which will be honed by a search for the missing depth and width measurements of Antarctic tidewater glaciers (confirmed search clues gladly accepted).

The pH variation can be zeroed in on a bit better by the new Appendices values (A, B, C, D, E, and F) based on a 1 mm sea level rise.

Plume flow changes are influenced by the flow of the substantial current that reaches completely around Antarctica (Mysterious Zones of Antarctica - 3).

They will not be able to be accurately ascertained until the distance between the grounding line and the ocean surface is known more accurately.

And don't forget pH (plume height) is not the same as glacier ice face height.

The variable pH is only the span of melt that generates a plume.

III. Purpose

My ultimate intent is to find alternate sources to replace the "missing" water when the erroneous (thermal expansion as "the major" or "a major" cause of sea level rise) hypothesis is no longer advocated  (On Thermal Expansion & Thermal Contraction, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38).

If calving, thermal plumes (ghost plumes), and basal melt plumes can make up the difference, that will balance the sea level change "budget" which is about 3.4 mm per year (global mean average) at this time.

IV. New Developments

Since acquiring the Bindschadler database and starting this new approach, I can see that the research is worthwhile.

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

No comments:

Post a Comment