Friday, February 2, 2018

On Thermal Expansion & Thermal Contraction - 32

Fig. 1
I. Background

In a recent post I indicated that a new software module I am developing had not yet been finished, even though I was presenting some output from the beta version of that module I was still working on.

That new module is focused on three depth layers, like previous Dredd Blog software had been (The Layered Approach To Big Water - 9).
Fig. 2a
Fig. 2b
Fig. 2c
Fig. 2d

So, today, I am presenting the portion that was not, at that time, finished.

NOTE: this new model uses only paired measurements, which are salinity (SP) and temperature (T) measurements taken at the same time, place, and depth (some previous Dredd Blog graphs were generated using all WOD measurements regardless of pairs).

Anyway, the new module focuses on thermal expansion and contraction of those three depth layers.

The geographical locations are the same (N. Hemisphere, S. Hemisphere, and Global Mean Average).

The global mean average is simply a combination of the two hemispheres.

The graph at Fig. 1 (upper left pane) shows tide gauge measured  sea level change over the years 1968-2017.

The upper right pane, and the two lower panes show the mean average versions of thermal expansion and/or contraction over that same period of time.

The bottom line totals for those Fig. 1 thermosteric volume changes are:

NH begin: = 15.9879
NH end: 28.9791
----------------------------------
net: 12.9912 mm

SH begin: 31.2034
SH end: 8.65903
----------------------------------
net: −22.54437

(−22.54437 + 12.9912) ÷ 2 = −4.7766

Mean Begin: 23.5956
Mean end: 18.819

18.819−23.5956 = −4.7766

In other words, the global mean for pairs indicates a negative volume change of 4.7766 mm over that span of time (nevertheless, sea level is rising).

The graphs at Fig. 2a - Fig. 2d show the thermal expansion and/or contraction at the three depths in the aforementioned hemispheres as well as in the global mean of those hemispheres and depths.

The point of it is that there is variance in thermosteric volume change at various depth layers in the hemispheres and in the global mean.

The graphs show that sometimes the deeper layers have more action in that regard than the upper layers do.

II. More Evidence For Cold Sea Water Melting Sea Ice

In addition to that, I found a paper which uses the TEOS-10 toolkit that I also use (Melting of Ice and Sea Ice into Seawater and Frazil Ice Formation, PDF).

That paper is very technical, dealing with sea water and sea ice at or very near the freezing point.

In so doing, it mentions the following TEOS-10 toolkit functions:
gsw_CT_from_t
gsw_frazil_ratios
gsw_CT_freezing_poly
gsw_CT_from_pt
gsw_t_freezing_first_derivatives
gsw_melting_ice_into_seawater
gsw_melting_ice_SA_CT_ratio
gsw_CT_freezing_first_derivatives
gsw_ice_fraction_to_freeze_seawater
gsw_melting_ice_equilibrium_SA_CT_ratio
gsw_enthalpy_first_derivatives_CT_exact
I mention this paper because I criticized the habit of calling the sea water "hot" that melts the most sea ice when describing a Chinese scientific paper that had called it "warm" (Questionable "Scientific" Papers - 17).

The reality is that both the Chinese and the Americans who wrote about it were puffing.

The highly scientific TEOS-10 source code comments place the word in quotes ("warm") when talking about very cold sea water temperatures that melt sea ice.

So, today I am going to elaborate on the TEOS-10 toolkit function "gsw_melting_ice_into_seawater" (gsw_melting_ice_into_seawater) in the hopes that it will shake some of the warming commentariat out of their trance (The Warming Science Commentariat, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11; cf. Climate Feedback).

III. The Temperate Reality

In preparing for future posts that will point out places where very cold water is melting sea ice, I am writing a module specifically for that purpose, again, based on the  "gsw_melting_ice_into_seawater" function of the toolkit.

The purpose of this exercise is to remind us that very little global warming can increase the temperature of cold, deep ocean waters just a little bit and still cause the melting of the ice sheets, ice shelves, and the land glaciers that protrude into ocean waters.

The following C++ program utilizes the TEOS-10 function "gsw_melting_ice_into_seawater" to calculate sea ice melting into water and the temperature of that same sea water that melted the ice:

#include <iostream>
#include <fstream>
#include <iomanip>

/** TEOS header file */
#include <gswteos-10 .h>

using namespace std;

/** values taken from TEOS-10 website */
const unsigned maxValues = 6;
const double SA[maxValues] ={34.7118,34.8915,35.0256,34.8472,34.7366,34.7324};
const double CT[maxValues] = {4.7856,2.4329,1.8103,1.2600,0.6886,0.4403};
const double P[maxValues] = {10,50,125,250,600,1000};
const double W_Ih[maxValues] = {0.0560,0.02513,0.02159,0.01210,0.00943,0.00751};
const double T_Ih[maxValues] = {-4.7856,-4.4329,-3.8103,-4.2600,-3.8863,-3.4036};

const char *txtFile = "icemelt.txt";

int main()
{
    freopen(txtFile, "w", stdout);

    for (unsigned cpos = 0; cpos < maxValues; cpos++)
    {
        /** input */
        double sa = SA[cpos], ct = CT[cpos], p = P[cpos];
        double w_ih = W_Ih[cpos], t_ih = T_Ih[cpos];

        /** output */
        double sa_final, ct_final, w_ih_final;

        gsw_melting_ice_into_seawater(sa, ct, p, w_ih, t_ih,
                                     &sa_final,
                                     &ct_final,
                                     &w_ih_final);

        cout << setprecision(15)
             << sa_final << "\t"
             << ct_final << "\t"
             << w_ih_final << endl;
    }

    return 0;
}

The program prints this into the file:
[SP]                [CT]                                  [w_ih]
32.7679392    -0.298448911022612    0
34.014676605    0.215263001418312    0
34.269397296    -0.074341719211558    0
34.42554888    0.207796293045473    0
34.409033862    -0.123785388299875    0
34.471559676    -0.202531182809225    0

Those results are what the toolkit EXAMPLE indicates (gsw_melting_ice_into_seawater).

Note that the numbers in red are the sea water temperatures before and after melting.

The temperatures (CT) are degrees Celsius (4.7856 C = 40.61408 F, 0.4403 C = 32.79254 F).

Those "hot" temperatures can be life threating:
Hypothermia can occur when you are exposed to ... 60°F (16°C) to 70°F (21°C) water [OR COLDER].
(WebMD). So, water "warm" or "hot" enough to melt subsurface ice sheets or ice shelves is actually cold enough to kill you if you are submerged in it long enough.

IV. Conclusion

Let's not be like the deniers, let's not get hyperbolic or hypothermia.

The previous post in this series is here.

Tuesday, January 30, 2018

The Layered Approach To Big Water - 9

Fig. 1a
Fig. 1b
Fig. 1c
I. Background

Saturday's post criticized headline and content "puffery" (a.k.a. hyperbole a.k.a. hype).
Fig. 2a
Fig. 2b
Fig. 2c

The going from "warm" to "hot" without convincing evidence was criticized as unwise for those who are not global warming induced climate change denialists (Questionable "Scientific" Papers - 17).

Today, I follow up on that post with data from the World Ocean Database (WOD) which was mentioned in that post (ibid).

II. New Stuff

I am also introducing a graph scenario that uses an old Dredd Blog practice of graphing depth layers of the world oceans.

That layer graphing was discontinued when the seven depths technique was changed to the thirty-three depths technique to match the WOD depths scheme.

The new layers currently consist of 0-700m, 701-2000m, and >2000m.

Those depth levels are the ones most often used in the papers I have read.

I have not included the thermal expansion graphs of these three depth layers because I have more work to do on that aspect of the "new stuff" presentation.

III. Analyzing The New Stuff

The graphs at Fig. 1a - Fig. 1c show that the ocean temperatures of the Northern Hemisphere (Fig. 1a), the Southern Hemisphere (Fig. 1b), and the combination of both hemispheres (Fig. 1c) show a slight decrease in overall ocean temperature (the numbers are presented later on in this post).

The word "hot" is not a wise word to use unless one wants to feed the trolls who call that "climate porn" (Pole Dancing In The Lab).

I recall Professor Rignot saying (concerning water temperatures that are melting Antarctica's ice sheets and shelves from below) that we should not take a bath in water at that temperature because we would freeze to death in it.

The point being that water at 4 deg C is 39.2 degrees F.

That cold, not hot, water will melt glacial ice which is at 0 deg C, because of the laws of thermodynamics (not because it is "hot" water).

Yes, "freezing cold water" will melt "ice cold ice" (and is doing so on a very massive scale in Greenland and Antarctica at this very moment).

IV. By The Numbers

Here are some actual numbers from the CSV file that Dredd Blog software generated to use for making the graphs at Fig. 1a - Fig. 1c mentioned above:
NH begin:
17.452.....(0-700m)
3.93645...(701-2000m)
2.44356...(>2000m)
======
23.83201 ÷ 3 = 7.944003333 Avg. (T)

NH end:
13.4354...(0-700m)
4.22991...(701-2000m)
3.2735.....(>2000m)
======
20.93881 ÷ 3 = 6.979603333 Avg. (T)

(7.944003333 - 6.979603333 = 0.9644 deg C decrease)

SH begin:
13.7684...(0-700m)
4.43371...(701-2000m)
1.29322...(>2000m)
======
19.49533 ÷ 3 = 6.498443333 Avg. (T)

SH end:
10.7843...(0-700m)
3.07471...(701-2000m)
1.21901...(>2000m)
======
15.07802 ÷ 3 = 5.026006667 Avg. (T)

(6.498443333 - 5.026006667 = 1.472436666 deg C decrease)

0.9644 + 1.472436666 ÷ 2 = 1.2184 deg C decrease (T)

NHSH begin:
15.6102
4.18508
1.86839
=======
21.66367 ÷ 3 = 7.221223333 Avg. (T)

NHSH end:
12.1098
3.65231
2.24625
=======
18.00836 ÷ 3 = 6.002786667 Avg. (T)

7.221223333 - 6.002786667 = 1.2184 deg C decrease (T)

Wouldn't it be nice if the gummit checkbook balanced that nicely?

Anyway, as you can see the Northern Hemisphere (NH) plus Southern Hemisphere (SH) WOD values match the Global (NHSH) values.

V. Salinity Graphs

The salinity graphs at Fig. 2a - Fig. 2c show some interesting severe gyrations that are not like the more reserved temperature patterns.

Those are likely due to freshening, El Nino / La Nina episodes, and perhaps precipitation (rain, snow).

VI. Concluding Caveats

We only know what we know about the world oceans from the measurements of the world (The World According To Measurements, 2, 3, 4, 5, 6, 7, 8, 9).

To make the graphs depicted in today's post, I began with about a billion measurements in the CTD and PFL datasets from the World Ocean Database.

I condensed them down into WOD zone pairs (salinity, temperature) in an SQL server database, and now work from it.

The quantity of measurements taken in the third depth level (>2000m) is not robust, compared to the quantity of measurements taken in the other two layers.

Even the ARGO flotilla, which is abundantly deployed, only goes down to about 2,000 meters.

Ignoring the other half of the ocean (2000 -> ~3686) then pontificating about how "hot" it is needs to stop.

That should be replaced with an active deep water flotilla to measure it at all depths (it is worth doing).

The previous post in this series is here.