Ice Sheet Melt According To Tide Gauge Stations

Fig. 1Tide Gauge Station Locations

In today's post we take a look at ice mass loss according to tide gauge records of measurements taken around the globe.

The graphic at Fig. 1 shows the extent of tide gauge stations.

There is also a link at Fig. 1 to a Permanent Service for Mean Sea Level (PSMSL) page which contains extensive tide gauge station information that is good enough to be used to calibrate satellite data collection instruments (NOAA, cf. Synchronizing Satellite Data With Tide Gauge Data).

The alleged problem spoken of in a recent paper (Thwaites) is fanciful for not realizing that tide gauge data covers up to two centuries in some cases.

Using a single glacier or a small number of them for reference is also problematic ("This result illustrates the risk of summarizing the ice sheet loss on the basis of the fate of a few glaciers." -Mouginot, Rignot et al., 2009, at 9242).

Fig. 2

Fig. 3

Fig. 4

The graphs at Fig. 2 and Fig. 3, for example, cover sea level changes with PSMSL records taken and recorded since 1809 (210 years).

The relatively new satellite record is tiny compared to the tide gauge record (Synchronizing Satellite Data With Tide Gauge Data).

With that in mind I thought I would calculate the number of gigatons of  ice melt using the hundreds of years of tide gauge records.

Before I get into how that is done, let's consider the graphs.

The graph at Fig. 2 shows the three types of sea level change (SLC).

Sea level rise (SLR), the black line on Fig. 2, is the most known to the public, sea level fall (SLF), the red line on Fig. 2, is less well known, and ghost water (green line) is virtually unknown to the public.

The graph at Fig. 4 shows the calculated ice melt (mass loss) associated with the SLR with and without including ghost water SLR.

You can see by the difference in the red line and the black line of Fig. 4 that ghost water is a necessary component of any complete SLC computation.

Let's now consider how to use the SLC record to calculate the ice mass loss.

To derive SLR (mm) from ice mass gigatonsdivide the gigatons value by 361.841, or to derive ice mass gigatons from an SLR value, multiply the SLR (mm) value by 361.841.

The Antarctica and Greenland tables below show the computations in the papers (Antarctic Ice Sheet, Rignot et al. 2019, Greenland Ice Sheet, Mouginot, Rignot, et al. 2019).

The tables also include my tide gauge computations so that comparisons can be made.

Remember that my calculations imply all of the Cryosphere, not just Antarctica and Greenland, so naturally the values will not match.

Also remember what a difference two centuries of data makes compared to four decades of data.

Here are the net comparisons between PSMSL data and the two papers:

Greenland
Rignot gt 1972 - 2018 = 5,406 (5,447 - 41)
Rignot gmsl mm 1972 - 2018 = 14.940291 (15.0536 − 0.113309)

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Greenland
PSMSL gt 1972 - 2018 = 28,570.8 (57,243.4 − 28,672.6)
PSMSL gmsl mm 1972 - 2018  = 78.9591 (158.2 − 79.2409)

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Antarctica
Rignot gt 1979 - 2018 = 4,450 (4,490 − 40)
Rignot gmsl mm 1979 - 2018 = 12.298254 (12.4088 −0.110546)

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Antarctica
PSMSL gt 1979 - 2018 = 20,027.3 (48,101.5 − 28,074.2)
PSMSL gmsl mm 1979 - 2018 = 55.3479 (132.935 − 77.5871)

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Totals (Greenland + Antarctica)

Rignot Gt: 9,856 (5,406 + 4,450)
Rignot GMSL mm: 27.238545 (14.940291 + 12.298254)

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PSMSL Gt: 48,598.1 (28,570.8 + 20,027.3)
PSMSL GMSL mm: 134.307 (78.9591 + 55.3479)

The countries with tide gauge stations I use (Countries With Sea Level Change - 2) (1,502 stations, 6 excluded) have to be added together properly, then averaged, in order to derive the generally useless global mean sea level (GMSL).

It is a common error to include SLF tide gauge stations with SLR tide gauge stations when calculating GMSL.

One reason for the error is memory loss (Woodworth 1888 and Newton have not been used).

Gravity has not been popular in sea level papers  (The Gravity of Sea Level Change, 2, 3, 4, 5) because the bathtub model is an easier sell to the public (The Bathtub Model Doesn't Hold Water, 2, 3, 4, 5).

So, where there is a net SLF I do not subtract that from the net SLR, because SLF is caused by the tide gauge station being near or within the hinge point of melting ice sheets (The Evolution and Migration of Sea Level Hinge Points, 2).

I only add the "ghost water" value ((-1.0 x SLF) x 0.27 "about a third" - Mitrovica), which is the quantity of water moving away from the coast of the Cryosphere location to another area far away, where it will then register on tide gauges as SLR (NASA Busts The Ghost).

The Tables:

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Antarctica Table

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Year	Rignot Era #	Rignot Era Year	Rignot Era GT	Rignot Total GT	Rignot GMSL (mm)	PSMSL GT Since 1809	PSMSL GMSL Since 1809 (mm)
1979	1	1	40	40	0.110546	28,074.2	77.5871
1980	1	2	80	80	0.221092	26,578.6	73.4537
1981	1	3	120	120	0.331637	29,495.7	81.5157
1982	1	4	160	160	0.442183	30,165	83.3654
1983	1	5	200	200	0.552729	36,543.1	100.992
1984	1	6	240	240	0.663275	29,729.9	82.1628
1985	1	7	280	280	0.773821	28,011.7	77.4145
1986	1	8	320	320	0.884366	27,626.8	76.3507
1987	1	9	360	360	0.994912	29,104.5	80.4345
1988	1	10	400	400	1.10546	28,729.8	79.3989
1989	1	11	440	440	1.216	31,016.9	85.7197
1990	1	12	480	480	1.32655	29,601.7	81.8086
1991	2	1	50	530	1.46473	30,094.3	83.1699
1992	2	2	100	580	1.60291	30,406.7	84.0333
1993	2	3	150	630	1.7411	29,296.4	80.9648
1994	2	4	200	680	1.87928	28,870.3	79.7874
1995	2	5	250	730	2.01746	30,585	84.526
1996	2	6	300	780	2.15564	32,307.3	89.286
1997	2	7	350	830	2.29383	33,796.8	93.4024
1998	2	8	400	880	2.43201	36,561.4	101.043
1999	2	9	450	930	2.57019	35,318.3	97.6072
2000	2	10	500	980	2.70837	34,573.2	95.5482
2001	3	1	166	1,146	3.16714	34,404.5	95.082
2002	3	2	332	1,312	3.6259	33,015.5	91.2431
2003	3	3	498	1,478	4.08467	35,713.5	98.6996
2004	3	4	664	1,644	4.54343	34,484.2	95.302
2005	3	5	830	1,810	5.0022	35,868	99.1265
2006	3	6	996	1,976	5.46096	35,419.7	97.8874
2007	3	7	1162	2,142	5.91973	36,523.2	100.937
2008	3	8	1328	2,308	6.37849	38,488.3	106.368
2009	3	9	1494	2,474	6.83726	38,631.7	106.764
2010	4	1	252	2,726	7.5337	42,531.8	117.543
2011	4	2	504	2,978	8.23013	40,538.5	112.034
2012	4	3	756	3,230	8.92657	42,234.2	116.72
2013	4	4	1008	3,482	9.62301	41,903.9	115.807
2014	4	5	1260	3,734	10.3194	42,633.2	117.823
2015	4	6	1512	3,986	11.0159	41,598.5	114.964
2016	4	7	1764	4,238	11.7123	46,872.4	129.539
2017	4	8	2016	4,490	12.4088	48,101.5	132.935

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Greenland Table

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Year	Rignot Era #	Rignot Era Year	Rignot Era GT	Rignot Total GT	Rignot GMSL (mm)	PSMSL GT Since 1809	PSMSL GMSL Since 1809 (mm)
1972	1	1	41	41	0.113309	28,672.6	79.2409
1973	1	2	82	82	0.226619	28,502.4	78.7704
1974	1	3	123	123	0.339928	28,159.7	77.8234
1975	1	4	164	164	0.453238	29,250.3	80.8374
1976	1	5	205	205	0.566547	25,221.4	69.7031
1977	1	6	246	246	0.679857	25,689.6	70.9969
1978	1	7	287	287	0.793166	27,452.2	75.8681
1979	1	8	328	328	0.906475	28,074.2	77.5871
1980	1	9	369	369	1.01978	26,578.6	73.4537
1981	2	1	51	420	1.16073	29,495.7	81.5157
1982	2	2	102	471	1.30168	30,165	83.3654
1983	2	3	153	522	1.44262	36,543.1	100.992
1984	2	4	204	573	1.58357	29,729.9	82.1628
1985	2	5	255	624	1.72451	28,011.7	77.4145
1986	2	6	306	675	1.86546	27,626.8	76.3507
1987	2	7	357	726	2.00641	29,104.5	80.4345
1988	2	8	408	777	2.14735	28,729.8	79.3989
1989	2	9	459	828	2.2883	31,016.9	85.7197
1990	2	10	510	879	2.42924	29,601.7	81.8086
1991	3	1	41	920	2.54255	30,094.3	83.1699
1992	3	2	82	961	2.65586	30,406.7	84.0333
1993	3	3	123	1,002	2.76917	29,296.4	80.9648
1994	3	4	164	1,043	2.88248	28,870.3	79.7874
1995	3	5	205	1,084	2.99579	30,585	84.526
1996	3	6	246	1,125	3.1091	32,307.3	89.286
1997	3	7	287	1,166	3.22241	33,796.8	93.4024
1998	3	8	328	1,207	3.33572	36,561.4	101.043
1999	3	9	369	1,248	3.44903	35,318.3	97.6072
2000	3	10	410	1,289	3.56234	34,573.2	95.5482
2001	4	1	187	1,476	4.07914	34,404.5	95.082
2002	4	2	374	1,663	4.59594	33,015.5	91.2431
2003	4	3	561	1,850	5.11274	35,713.5	98.6996
2004	4	4	748	2,037	5.62954	34,484.2	95.302
2005	4	5	935	2,224	6.14635	35,868	99.1265
2006	4	6	1122	2,411	6.66315	35,419.7	97.8874
2007	4	7	1309	2,598	7.17995	36,523.2	100.937
2008	4	8	1496	2,785	7.69675	38,488.3	106.368
2009	4	9	1683	2,972	8.21355	38,631.7	106.764
2010	4	10	1870	3,159	8.73035	42,531.8	117.543
2011	5	1	286	3,445	9.52076	40,538.5	112.034
2012	5	2	572	3,731	10.3112	42,234.2	116.72
2013	5	3	858	4,017	11.1016	41,903.9	115.807
2014	5	4	1144	4,303	11.892	42,633.2	117.823
2015	5	5	1430	4,589	12.6824	41,598.5	114.964
2016	5	6	1716	4,875	13.4728	46,872.4	129.539
2017	5	7	2002	5,161	14.2632	48,101.5	132.935
2018	5	8	2288	5,447	15.0536	57,243.4	158.2

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That is all for today folks.

In the next post I will furnish the 1809 - 2018 Table used to produce Fig. 2 - Fig. 4 because this post is big enough already.

Review the excellent presentation in the video below, by Dr. Mitrovica, if you like.

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