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Major paper shows massive loss of Antarctic ice over the last few decades.

No, you do not need to have a number value for the tide at any given time/location. How could you? You can have a number for the sea level at any given time/location, but how do you know what contribution the tide makes to that level, and what is due to other causes? Answer: Fourier analysis. This tells you how much of the level is periodic and how much is due to non-periodic causes.
Saying they do not need a number value for a given location does not make it true.
Again Fourier analysis only corrects for the theoretical sinusoidal functions, if there are other variables, (and there are) then the
correction factor applied is itself incorrect.
 
What? Firstly, we were talking about the contribution to sea level rise due to melting Antarctica ice, not total sea level rise. Secondly, the graph quite clearly shows more rapid sea level rise since the year in question (2012). This doesn't support your statement the rate has been slowing since 2012 at all!
There is a noticeable slowdown post 2014, and the last time I checked 2014 is also since 2012.
 
Tides are so variable worldwide that it'd be enormously complicated to factor them in to sea level prediction. The only useful number is the high tide mark.
Where I live there's two tides a day, but one low is kind of a false low, it only goes down half as much as the other low. Last week we had the lowest tide in 40 years. In some places there's only one tide a day. In some places the high and low is only a foot or two, and it can be 40 feet in other places.
I know it is very complicated, which is what I am trying to explain.
To measure the sea level, the satellite must correct for the tide, at the place and time of the measurement,
Since they do not have an actual measurement, the correction is the predicted tide for that time and place.
Tides in my area (Gulf of Mexico) are minimal, yet can be off by 300 mm or more on any given day.
If I look at the tide station in Port Angeles,
https://tidesandcurrents.noaa.gov/stationhome.html?id=9444090
They look to have about a 8 foot swing in the tide with an error in the 80 mm frame.
If they corrected the satellite signal with the predicted tide, it could be anywhere from 0 to 80 mm in error.
(If they did not correct for the tide the error could be 2 meters or more.)
 
Saying they do not need a number value for a given location does not make it true.
Again Fourier analysis only corrects for the theoretical sinusoidal functions, if there are other variables, (and there are) then the
correction factor applied is itself incorrect.

But the variations that are not periodic are not tides. We are talking about the correction for tides!
 
I know it is very complicated, which is what I am trying to explain.
To measure the sea level, the satellite must correct for the tide, at the place and time of the measurement,
Since they do not have an actual measurement, the correction is the predicted tide for that time and place.
Tides in my area (Gulf of Mexico) are minimal, yet can be off by 300 mm or more on any given day.
If I look at the tide station in Port Angeles,
https://tidesandcurrents.noaa.gov/stationhome.html?id=9444090
They look to have about a 8 foot swing in the tide with an error in the 80 mm frame.
If they corrected the satellite signal with the predicted tide, it could be anywhere from 0 to 80 mm in error.
(If they did not correct for the tide the error could be 2 meters or more.)

No, you are explaining nothing. You are making it up as you go along. I have already explained how you can eliminate the influence of tides by using Fourier analysis to remove the periodic changes.
 
No, you are explaining nothing. You are making it up as you go along. I have already explained how you can eliminate the influence of tides by using Fourier analysis to remove the periodic changes.
You can only remove the astronomical tide predictions, you will still have a significant error related to the other variables
which affect the measurement at that time and place.
 
Sea level rise: isostatic adjustment

Posted on June 23, 2018 by curryja | 53 comments
by Judith Curry
A discussion thread to ponder the uncertainties in glacial isostatic adjustment and the implications for past and future sea level rise.
Continue reading

Comparison with tide guages
Those that are skeptical of the satellite observations argue ‘but the tide guages.’ As reported in Part IV, there have been several studies that compare the tide guage with altimeter values during the period since 1993 and find good agreement:
Merrifield et al. (2009): After 1990, the global trend increases to the most recent rate of 3.2 ± 0.4 mm yr-1, matching estimates obtained from satellite altimetry.
Jevrejeva et al. (2014): There is a good agreement between the rate of sea level rise (3.2 ± 0.4 mm· yr-1) calculated from satellite altimetry and the rate of 3.1 ± 0.6 mm·yr-1 from tide gauge based reconstruction for the overlapping time period (1993–2009).
Hay et al. (2015): Our analysis, which combines tide gauge records with physics-based and model-derived geometries of the various contributing signals, also indicates that GMSL rose at a rate of 3.0 ± 0.7 millimetres per year between 1993 and 2010 . . . is also consistent with the estimate based on TOPEX and Jason altimeter measurements (3.2 ± 0.4 mm yr-1 for the period 1993–2010.)
Dangendorf et al. 2016: our estimate of 3.1 ± 1.4 mm⋅y−1 from 1993 to 2012 is consistent with independent estimates from satellite altimetry.
So, what actually went into these analyses? Dangendorf (2016) describes what they did:
Here we present a GMSL reconstruction that accounts for ocean volume redistribution, local observations [mostly global positioning system (GPS)] of VLM, and geoid changes caused by ongoing GIA, present-day ice melt, and TWS, including ground- water depletion and water impoundment behind dams. We base our approach on an area-weighting average technique and on recent scientific achievements made for each individual correction. Our tide gauge selection consists of 322 stations, for which VLM corrections with uncertainties of less than 0.7 mm/yr are available. After accounting for VLM, each tide gauge is further corrected for geoid changes from ongoing GIA, glacier/ice-sheet melting, and TWS. The tide gauges are then grouped into six coherent regions objectively defined to account for water volume redistribution. Within each oceanic region, a regional mean sea level curve is built by recursively combining the two nearest stations into a virtual station halfway, until only one station is left.
After all this, one is still left with the argument ‘but the tide guages.’ . . . .

Summary
Assuming that the uncertainty in GIA adjustments are ‘in the noise’ of global sea level rise may not be entirely justified. The adjustments to the satellite data that emerged in the discussion between Morner and Nerem do not inspire confidence in the estimate of sea level rise from satellite data, and the low level of stated uncertainty strains credulity.
I would appreciate any additional insights you have on this topic, recent references, etc.



 
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[h=1]Worse than they thought: Antarctica actually colder than scientists once believed[/h]From the AGU and the “but, but, the continent is melting!” department. COLDEST PLACE ON EARTH IS COLDER THAN SCIENTISTS THOUGHT WASHINGTON — Tiny valleys near the top of Antarctica’s ice sheet reach temperatures of nearly minus 100 degrees Celsius (minus 148 degrees Fahrenheit) in the winter, a new study finds. The results could change…
Continue reading →

but... but... but...

They keep telling us the science is settled.

Are they morons?
 
The narrative continues to unravel.

Evidence of an active volcanic heat source beneath the Pine Island Glacier
Abstract
Tectonic landforms reveal that the West Antarctic Ice Sheet (WAIS) lies atop a major volcanic rift system. However, identifying subglacial volcanism is challenging. Here we show geochemical evidence of a volcanic heat source upstream of the fast-melting Pine Island Ice Shelf, documented by seawater helium isotope ratios at the front of the Ice Shelf cavity. The localization of mantle helium to glacial meltwater reveals that volcanic heat induces melt beneath the grounded glacier and feeds the subglacial hydrological network crossing the grounding line. The observed transport of mantle helium out of the Ice Shelf cavity indicates that volcanic heat is supplied to the grounded glacier at a rate of ~ 2500 ± 1700 MW, which is ca. half as large as the active Grimsvötn volcano on Iceland. Our finding of a substantial volcanic heat source beneath a major WAIS glacier highlights the need to understand subglacial volcanism, its hydrologic interaction with the marine margins, and its potential role in the future stability of the WAIS.

Volcanic heat source discovered under Pine Island Glacier, the poster child for Antarctic melting

Anthony Watts / 19 hours ago June 26, 2018
volcanic-pine-island-glacier1-720x452.jpg

[heat source] Plays critical role in movement, melting
Via Eurekalert KINGSTON, R.I. — June 22, 2018 — A researcher from the University of Rhode Island’s Graduate School of Oceanography and five other scientists have discovered an active volcanic heat source beneath the Pine Island Glacier in Antarctica.
The discovery and other findings, which are critical to understanding the stability of the West Antarctic Ice Sheet, of which the Pine Island Glacier is a part, are published in the paper, “Evidence of an active volcanic heat source beneath the Pine Island Glacier,” in the latest edition of Nature Communications.
Assistant Professor Brice Loose of Newport, a chemical oceanographer at GSO and the lead author, said the paper is based on research conducted during a major expedition in 2014 to Antarctica led by scientists from the United Kingdom. They worked aboard an icebreaker, the RRS James Clark Ross, from January to March, Antarctica’s summer. . . .


 
The narrative continues to unravel.

[FONT=&][/FONT][FONT=&]Evidence of an active volcanic heat source beneath the Pine Island Glacier[/FONT]
[FONT=&]Abstract[/FONT]
[FONT=&]Tectonic landforms reveal that the West Antarctic Ice Sheet (WAIS) lies atop a major volcanic rift system. However, identifying subglacial volcanism is challenging. Here we show geochemical evidence of a volcanic heat source upstream of the fast-melting Pine Island Ice Shelf, documented by seawater helium isotope ratios at the front of the Ice Shelf cavity. The localization of mantle helium to glacial meltwater reveals that volcanic heat induces melt beneath the grounded glacier and feeds the subglacial hydrological network crossing the grounding line. The observed transport of mantle helium out of the Ice Shelf cavity indicates that volcanic heat is supplied to the grounded glacier at a rate of ~ 2500 ± 1700 MW, which is ca. half as large as the active Grimsvötn volcano on Iceland. Our finding of a substantial volcanic heat source beneath a major WAIS glacier highlights the need to understand subglacial volcanism, its hydrologic interaction with the marine margins, and its potential role in the future stability of the WAIS.

[/FONT]
Volcanic heat source discovered under Pine Island Glacier, the poster child for Antarctic melting

Anthony Watts / 19 hours ago June 26, 2018
[FONT=&]
volcanic-pine-island-glacier1-720x452.jpg

[FONT=&][heat source] Plays critical role in movement, melting[/FONT]
[FONT=&]Via Eurekalert KINGSTON, R.I. — June 22, 2018 — A researcher from the University of Rhode Island’s Graduate School of Oceanography and five other scientists have discovered an active volcanic heat source beneath the Pine Island Glacier in Antarctica.[/FONT]
[FONT=&]The discovery and other findings, which are critical to understanding the stability of the West Antarctic Ice Sheet, of which the Pine Island Glacier is a part, are published in the paper, “Evidence of an active volcanic heat source beneath the Pine Island Glacier,” in the latest edition of Nature Communications.[/FONT]
[FONT=&]Assistant Professor Brice Loose of Newport, a chemical oceanographer at GSO and the lead author, said the paper is based on research conducted during a major expedition in 2014 to Antarctica led by scientists from the United Kingdom. They worked aboard an icebreaker, the RRS James Clark Ross, from January to March, Antarctica’s summer. . . . [/FONT]
[/FONT]
[FONT=&]
[/FONT]

Which narrative is supposed to be unravelling?

As the article continues:

Does that mean that global climate change is not a factor in the stability of the Pine Island Glacier?

No, said Loose. “Climate change is causing the bulk of glacial melt that we observe, and this newly discovered source of heat is having an as-yet undetermined effect, because we do not know how this heat is distributed beneath the ice sheet.”

He said other studies have shown that melting caused by climate change is reducing the size and weight of the glacier, which reduces the pressure on the mantle, allowing greater heat from the volcanic source to escape and then warm the ocean water.
 
Which narrative is supposed to be unravelling?

Excuse Junkies are addicted to excuses.

It doesn't need to be good, or even remotely plausible. It only needs to fake having substance to satisfy their addiction.
 
Which narrative is supposed to be unravelling?

As the article continues:
Does that mean that global climate change is not a factor in the stability of the Pine Island Glacier?

No, said Loose. “Climate change is causing the bulk of glacial melt that we observe, and this newly discovered source of heat is having an as-yet undetermined effect, because we do not know how this heat is distributed beneath the ice sheet.”

He said other studies have shown that melting caused by climate change is reducing the size and weight of the glacier, which reduces the pressure on the mantle, allowing greater heat from the volcanic source to escape and then warm the ocean water.
Undetermined effect cuts both ways. In the past, they calculated (SWAG'd it) CO2 warming based on zero, and near zero warming of other variables.

Please note... Climate change does not mean man made climate change!!!

It includes natural causes!!!

The wording appears to be rationalizing the failure of proper science.
 
I'm not in the debate about what is causing the ice-melting.

I'm just listening to the astronauts that have been watching this from space for about the last 30 years, because they have a front row seat in watching it happen- and have before and after photos to prove it.

Now, having that said- you may all go back to arguing about what is causing it.

Be sure to politicize it and blame it on your political adversaries! That always works! Right?
 
I'm not in the debate about what is causing the ice-melting.

I'm just listening to the astronauts that have been watching this from space for about the last 30 years, because they have a front row seat in watching it happen- and have before and after photos to prove it.

Now, having that said- you may all go back to arguing about what is causing it.

Be sure to politicize it and blame it on your political adversaries! That always works! Right?

Really?

Who is lying to you about that? Or... perhaps you are throwing out some feces to see if it sticks?

How many astronauts have ever been up there in a polar orbit?
 
Really?

Who is lying to you about that? Or... perhaps you are throwing out some feces to see if it sticks?

How many astronauts have ever been up there in a polar orbit?

Dude, I could lead any jackass to the water- but I can't make them drink it.

Just look at the before and after pictures taken from space by the astronauts. And drink up! LOL!
 
Dude, I could lead any jackass to the water- but I can't make them drink it.

Just look at the before and after pictures taken from space by the astronauts. And drink up! LOL!
Please link to the pictures in question, least we find different pictures with different subjective results.
 
Please link to the pictures in question, least we find different pictures with different subjective results.

Come on dude, you don't live in a bubble- those pictures from space are out on the web for all to see- and have been available all along.

Don't tell me, you didn't ever get off your high horse, take a minute, and check things out for yourself.

I'll tell you what, since you are arguing the fact that the ice is not melting, you show us the before and after photos that supports your theory.

Come on dude, do I need to come and burp you over my shoulder too? LOL!

Man, at least, keep up with the 5th graders!
 
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Come on dude, you don't live in a bubble- those pictures form space are out on the web for all to see- and have been available all along.

Don't tell me, you didn't ever get off your high horse, take a minute, and check things out for yourself.

I'll tell you what, since you are arguing the fact that the ice is not melting, you show us the before and after photos that supports your theory.

Come on dude, do I need to come and burp you over my shoulder? LOL!

It is not that, it is that you need to specify which pictures you are talking about,
so we do not look at the wrong pictures by mistake!
 
It is not that, it is that you need to specify which pictures you are talking about,
so we do not look at the wrong pictures by mistake!

OK sorry! The NASA website has all the photos.

NASA also has photos of the extreme clouds of smog that hovers over Asia- that some people argue is causing a depletion of our ozone layer at a rapid pace!

NASA does not take positions on Climate change- they just show pictures of earth and leave that to scientists to figure out.

One tip I'd like to leave you with! And that is- don't let your political view- obstruct the real view from space!
 
OK sorry! The NASA website has all the photos.

NASA also has photos of the extreme clouds of smog that hovers over Asia- that some people argue is causing a depletion of our ozone layer at a rapid pace!

NASA does not take positions on Climate change- they just show pictures of earth and leave that to scientists to figure out.

One tip I'd like to leave you with! And that is- don't let your political view- obstruct the real view from space!

Again, unless you cite the specific photos you are talking about, we have no way of knowing any photos
we might find are the one you mean.
 
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