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Messages - salbers

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Permafrost / Re: Arctic Methane Release
« on: June 16, 2019, 10:43:01 PM »
Here's a recent paper by S&S in case it has yet to be posted:

As I mentioned elsewhere, a recent PNAS paper shows SLR is accelerating at .08mm/yr^2. One can look at the doubling time of each component and there we see Antarctic Ice Sheets have a relatively low contribution now, though the shortest doubling time, on the order of 6 years. The overall doubling rate of the rise is roughly 35 years.

And GRACE data shows the more specific acceleration of the Antarctic Ice Sheets.

Comparing the size of the heat sinks represented by the main ice masses:
Arctic              25,600 cu km (mid winter)
Greenland   2,850,000 cu km
Antarctic  26,500,000 cu km

So Arctic peak winter ice volume is about 1% of Greenland's, and Greenland's is 10% of Antarctica's.  Thus the heat which disposes of most of the Arctic's ice in summer, is having a significant input to Greenland's ice mass too.  The less Arctic ice there is, the more the heat goes into the Greenland heat sink, and the adjacent ocean. 

Its kinda the inverse of a scheme to pay off debts.  Pay off the smallest first, then there is much more to pay off the next.  Get rid of Arctic ice, then with that job done that heat will hit Greenland hard.  Hanson's exponential rate of change of SLR becomes more likely every day.

Science / Re: Sea Level Rise Accelerating
« on: March 04, 2018, 08:06:49 PM »
Indeed the 65cm value is a reasonable estimate of a simple quadratic extrapolation. One might also calculate a quadratic estimate of each component. Then the sum of the total will no longer be quadratic. The Antarctic component doubling each 6 years would come to dominate and the total value by 2100 seems it could be more than 65cm.

Antarctica / Re: Potential Collapse Scenario for the WAIS
« on: March 04, 2018, 08:00:09 PM »
Recent GRACE measurements show accelerating ice loss over Antarctica in general with a concentration over the WAIS:

Science / Sea Level Rise Accelerating
« on: March 04, 2018, 07:40:20 PM »
A recent PNAS paper shows SLR is accelerating at .08mm/yr^2. One can look at the doubling time of each component and there we see Antarctic Ice Sheets have a relatively low contribution now, though the shortest doubling time, on the order of 6 years. The overall doubling rate of the rise is roughly 35 years.

Permafrost / Re: Arctic Methane Release
« on: October 29, 2017, 09:09:21 PM »
This will be the year to go.  Wonder why it's in NO, it's always been in SF.
Interesting to see all the updates about AGU and S&S. The AGU Fall Meeting is in New Orleans this year and next due to subway construction in S.F.

Permafrost / Re: Arctic Methane Release
« on: August 06, 2017, 09:11:31 PM »
Do these less alarming assessments consider fully the methane gas locked underneath the hydrates?

So now, evidence from both poles is suggesting methane release (will of course be bad) but not perhaps as bad as previously thought (Shakhova, Wadhams, and others have strongly warned about methane danger).

(And this is one you may have seen already --->

Permafrost / Re: Arctic Methane Release
« on: July 04, 2017, 08:26:25 PM »
Not sure if this was already posted in another topic perhaps, but it is well worth reading;
Interview by Nick Breeze with Dr Natalia Shakhova and Dr Igor Semiletov, a very good job by all.
Very interesting - lots of details in the article and in the paper. A quick note is that 3 kilograms in the hotspots is 6 orders of magnitude larger than 3 milligrams overall.

Permafrost / Re: This is not good (methane clathrates)
« on: May 06, 2017, 11:15:49 PM »
Unsure if it was posted yet - this paper suggests a role of methane hydrates in the great Permian Extinction around 230 million years ago.

Permafrost / Re: Toward Improved Discussions of Methane & Climate
« on: May 06, 2017, 10:53:35 PM »
The issue is not whether landmasses move from the rotational adis, they don't (except by tectonic movements which is totally different).  the rotational axis itself shifts, tilting or wobbling its position relative to the sun.  this is a historical cycle that normally does affect the cycle of glacial and interglacial periods.  however, climate change is progressing far more rapidly than any recent period, so i don't think any major earth changes that happen over a thousand years from now are particularly relevant today.  i DO think it's important to understand this in the context of paleoclimate data.
Indeed the Milankovitch cycles are important in the paleoclimate context. More specifically there are changes in the Earth axis tilt. Precession will also change which hemisphere is closest to the sun during a particular season. For example presently Antarctica has its summer when the Earth is near perihelion, so there is more reflection by the ice sheet. The lowers the Earth's overall temperature. A third cycle is changes in the eccentricity, so this would modulate the precession effect.

Permafrost / Re: Toward Improved Discussions of Methane & Climate
« on: May 06, 2017, 05:20:08 PM »
It may help to consider the baseline values of CO2 and CH4 being compared against. In addition the forcing from CO2 is logarithmic, and from CH4 is approximately a square root dependence (and also dependent on N2O). (see Table 1)

If we use the year 1750 as a reference for methane it would be 700ppb. Good question about the earlier farming impact. Prior to that the average over the past million years is about 500ppb, with variations up to about 700ppb.

The total CO2e from the non-CO2 gases is about 90ppm. CH4 has about 25% the radiative forcing of CO2 at present, compared with the year 1750 reference amounts of each. However a new study has this fraction closer to one third, when shortwave IR absorption features are accounted for.

Permafrost / Re: This is not good (methane clathrates)
« on: April 20, 2017, 01:44:11 AM »
Frankendoodle - it's a function of depth (as well as temperature and saturation). It can be anywhere from 0+ to 99+%.

From the 50M depth of the ESS it's likely to be around 90+%.
I've seen a diagram (hope I can find it again) where this is a function of bubble size also.

Permafrost / Re: This is not good (methane clathrates)
« on: April 14, 2017, 07:13:42 PM »
Thought I'd add this review article in the present thread as well:

Here are some details on satellite methane observations and modeling methods.

They mention an upcoming instrument called TROPOMI that should give some improved methane measurements from space, with a projected launch this August.

And another article on figuring out how much methane is coming from the ESAS:

Policy and solutions / Re: LENR as a new energy source?
« on: March 26, 2017, 07:20:36 PM »
Anyone care to comment more on the science and experimental procedure in the arxiv paper (reply #10)?

This could be a scam, though I've yet to be convinced that all the other replicators and researchers reporting excess energy are also scams.

Policy and solutions / Re: LENR as a new energy source?
« on: March 26, 2017, 03:28:56 PM »
There is this new arxiv paper that gives a description of a newer LENR device and the theory behind it.

Permafrost / Re: Methane Release: Information Required for Article
« on: June 05, 2016, 01:35:30 AM »
You might ask Dr. Natalia Shakhova what is unique about the present situation, and maybe how it compares with the past? This would apply at least to the shallow underwater permafrost.

Unsure though about whether all this emission is presently increasing and whether it is responsible for the uptick in global methane over the past 5-7 years.

Permafrost / Re: This is not good.
« on: May 18, 2016, 11:37:01 PM »
Couple of points from the NOAA/GMD annual meeting as to why some are less alarmed about Arctic Methane trends.

1) The excess of CH4 ground-based values of north polar latitudes vs south polar latitudes is actually less now than in the 1990s. The main reason is the fall of the Soviet Union.

2) The suggestive spikes in Barrow's CH4 measurements happen during southerly winds, so they are from local land sources.

So this should hopefully be squared with the other evidence being discussed in this thread to have a consistent picture of things?

Permafrost / Re: Arctic Methane Release
« on: April 23, 2016, 07:20:53 PM »
Good point about the timing of the papers. The paper you cited does have some good suggestions in the conclusions, such as improving the observation network.

Permafrost / Re: Arctic Methane Release
« on: April 23, 2016, 06:27:12 PM »
The question then is how this can be reconciled with the higher (though uncertain) estimates (e.g. by Shakhova et. al. in 2014,2015).

Ebullition and storm-induced methane release from the East Siberian Arctic Shelf.

The East Siberian Arctic Shelf: towards further assessment of permafrost-related methane fluxes and role of sea ice.

Permafrost / Re: This is not good.
« on: December 24, 2015, 05:40:30 PM »
There is a September 2015 paper by Natalia Shakhova here that talks about methane fluxes and such from the ESAS:

Policy and solutions / Re: LENR as a new energy source?
« on: November 07, 2015, 07:55:53 PM »
isotopic abundances in natural material have discreet levels for different isotopes with varying decay rates.  For instance, you won't find plutonium naturally anywhere on the earth since its decay rate is so fast.  Similarly, if a fusion reaction produced copper isotopes, then you would find shorter-lived isotopes that are not found in nature.  Sadly, that is not the case with this technology.

The claims appear to be patently false and any assertion of orders or working prototypes are either lies or the result of deceived investors.

On the other hand, there are supposedly isotopic shifts going on: (see section eight)

Policy and solutions / Re: LENR as a new energy source?
« on: November 05, 2015, 09:25:45 PM »
Seems like an incomplete refutation, since the LENR theory is that lattice effects are different from what goes on in stars.

Policy and solutions / LENR as a new energy source?
« on: October 30, 2015, 09:10:37 PM »

Permafrost / Re: Toward Improved Discussions of Methane & Climate
« on: July 05, 2015, 11:37:08 PM »
There may be some confusion in the context of the Earth Axis discussion. I think the original implication was that the geographic latitude of Siberia or other places changes significantly in just a few millenia. This is not the case. Precession is a wobbling motion that does cause the Earth's axis to move relative to the "fixed" stars. However the distance of any particular landform from the rotational pole isn't changing significantly.

Permafrost / Re: This is not good.
« on: June 27, 2015, 12:33:17 AM »
Also this analysis of the top down vs bottom up methane budget

reaches a different conclusion than what was presented at a NOAA/GMD meeting this May.

Permafrost / Re: Toward Improved Discussions of Methane & Climate
« on: June 27, 2015, 12:01:24 AM »
Oh boy, you're not going to like this. From a catastrophists point of view the east siberian shelf was further from the axis of rotation prior to about 5,200 years bp and even further away before about 11,500 years bp. The axis being before that pretty much where the geomagnetic pole is.
The Earth's axis doesn't change that fast from as far as I know.

Permafrost / Re: This is not good.
« on: June 26, 2015, 07:32:58 PM »
Interesting about the attached figure from this website:

It shows a high hourly methane reading at Barrow, though I'm unable to reproduce this figure going directly to NOAA's web site.

Permafrost / Re: This is not good.
« on: June 07, 2015, 07:41:34 PM »
Here is the longer term trend at Nunavut. The rate is now spiking and is at a record high, though a similar rate of rise did occur during the 1980s. It will be interesting to see if things accelerate beyond this.

Permafrost / Re: This is not good.
« on: June 07, 2015, 05:30:10 PM »
Hope they don't start punching too many holes in the metastable methane hydrates...

To help evaluate recent measurements, here is the "normal" methane distribution by latitude and season from a book in a Google Search.

Permafrost / Re: This is not good.
« on: June 05, 2015, 09:38:17 PM »
The NOAA site looks like it has some more powerful plotting features we can explore. For example I made an animated time-series plot of the latitudinal dependence of CH4. So far though the plot I made only goes up to 2009.

Also, below is a time-series plot of the new Siberia station.

Permafrost / Re: This is not good.
« on: June 01, 2015, 01:05:31 AM »
Glad to see Vergent picked up this thread over here. I hear that Nunavut Flasks measured by NOAA are picking up with methane. On the other hand there was a recent cruise in the Laptev Sea that was inconclusive about the ESAS.

I saw a few minutes of this NOAA talk on May 19th, casting doubt on large ESAS emissions, in terms of a ship measuring CH4 well offshore in the Laptev Sea.
Shakhova is also quoted in this NOAA paper on Carbon-Tracker Methane. The paper suggests no strong trend in the ESAS yet if you read some of the details:

In the May 19th talk, the argument was made that rising sea level will stabilize methane in the ESAS since the pressure would rise. However that seems to be a relatively small negative feedback. It was also mentioned that by the time we detect a clear trend it will be too late to stop it. Also, methane extraction activities in the area could contribute to speeding up the release.

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