Thursday, March 17, 2016

Is A New Age Of Pressure Upon Us? - 8

Fig. 1
The next post will deal with sea level change where major world ports are located, but today we look at Antarctica once again.

Tide gauge stations in that harsh environment are rare compared to less harsh environments.

The new tide gauge record databases I downloaded have some tide gauge data that can be used for pondering sea level events there.

The graph at Fig. 1 concerns data at Almirante Brown Station 858 on the West Antarctic Peninsula.

It stopped being a station circa 1980.

Fig. 2
The graph at Fig. 4 is another Antarctic tide gauge station Argentine Islands, #913.
 as is Fig. 7, which is Rothera, Stn. #1931.
Fig. 3

Fig. 4
Those links to the PSMSL site contain maps that can be minimized until other gauges in the vicinity become visible.
Fig. 5

Fig. 6
All in all, they indicate in general, like records for the Greenland area do, that areas of sea level fall occur near large ice sheets as those ice sheets melt (e.g. Proof of Concept  3, 5).
Fig. 7

Fig. 8
The big story these days is that Antarctica and Greenland are melting underneath the surface at surprising depths.

If you take a look at Fig. 10 you will see that the warmest water under the Antarctic ice shelves is at a depth of about 400 meters (~1,312 feet).
Fig. 9

Recent articles (h/t reader Mark Hanson) indicate that the melt "works its way" through weak areas in the ice shelves as the warm water is pulled upward by, among other things, the ice sheet gravity: "The cause is not warming air temperatures, as Mercer had suspected, but rather warmer ocean waters reaching the base of the coastal glaciers – which are rooted hundreds of meters below sea level – and melting them from below." (Washington Post).

Reliance on the Bathtub Model and the Thermal Expansion myths have mislead a lot of researchers.

The implications and impacts of that misdirection have allowed a threat to civilization itself to develop (Why Sea Level Rise May Be The Greatest Threat To Civilization, 2, 3, 4, 5),
Greenland & Antarctica Invade The United States, 2, 3, 4).

However, the science on record may be forcing researchers to  abandon those myths ("... we conclude that most of the change in ocean mass is caused by the melting of polar ice sheets and mountain glaciers (Satellite data study, cf. Nature Geoscience).

The latter paper has a phrase in it that I hope to use in place of "bullshit" in the future, so as to "sound more scientific."

That spot-on phrase to replace the phrase "mythological bullshit" is: "the bleeding of terrestrial signals into the ocean data" (ibid).
Fig. 10 GISS data

Anyway, the situation is quite serious because the Thwaites Glacier, mentioned in that literature, is now problematic in several ways.

I wrote about it in the geothermal context a while back.

A quote from one of the papers I cite to in one of those posts presents this concern:
"Thwaites Glacier is one of the West Antarctica’s most prominent, rapidly evolving, and potentially unstable contributors to global sea level rise. Uncertainty in the amount and spatial pattern of geothermal flux and melting beneath this glacier is a major limitation in predicting its future behavior and sea level contribution. In this paper, a combination of radar sounding and subglacial water routing is used to show that large areas at the base of Thwaites Glacier are actively melting in response to geothermal flux consistent with rift-associated magma migration and volcanism. This supports the hypothesis that heterogeneous geothermal flux and local magmatic processes could be critical factors in determining the future behavior of the West Antarctic Ice Sheet"
(Is A New Age Of Pressure Upon Us? - 6). That post refers to some recent cases in Iceland where glacial thinning triggered volcanic activity which further degraded ice mass.

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

3 comments:

  1. Awesome work D!

    Love the New White Trash!

    http://www.etcgroup.org/content/etcs-irreverent-review-2015-and-possibly-irrelevant-preview-2016

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  2. Thanks Dredd!
    You'll use a lot more chalk than you expected, but eventually, the people will understand.

    One of my fave quotes ( Upton Sinclair)

    "It is difficult to get a man to understand something when his salary depends upon his not understanding it."

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