Melting of ice sheets and sea level rise

[HBS Guy]

The new estimate shows there has been a six-fold increase in annual land ice contribution to global sea level rise from the mid-1990s to the early 2010s.

Land ice describes permanent ice on the surface of the Earth, which comprises the two ice sheets that cover Antarctica and Greenland as well as numerous smaller glaciers and ice caps.

Over the course of the 20th century, melting glaciers and ice caps dominated the overall contribution of land ice to global sea level rise.

This has changed over the last few decades due to the accelerating contribution of the Greenland and Antarctic ice sheets. Ice sheets are the largest potential source of future sea level rise and represent the largest uncertainty in projections of future sea level.

This new study, to be published next week in the journal Environmental Research Letters, but already available online, suggests that for the most recent five-year period (2012-2016), land ice contributed around 1.85 mm per year to global sea level rise. The largest source was Greenland (37 percent of the total, or 0.69 mm per year) followed by glaciers and ice caps (34 percent or 0.63 mm per year). Antarctica contributed the remainder, with the vast-majority from West Antarctica (26 percent or 0.48 mm per year)

http://www.bristol.ac.uk/news/2018/june/land-ice-sea-level-rise.html

[HBS Guy]

Global probabilistic projections of extreme sea levels show intensification of coastal flood hazard
Michalis I. Vousdoukas, Lorenzo Mentaschi, Evangelos Voukouvalas, Martin Verlaan, Svetlana Jevrejeva, Luke P. Jackson & Luc Feyen

Nature Communicationsvolume 9, Article number: 2360 (2018) | Download Citation

Abstract

Global warming is expected to drive increasing extreme sea levels (ESLs) and flood risk along the world’s coastlines. In this work we present probabilistic projections of ESLs for the present century taking into consideration changes in mean sea level, tides, wind-waves, and storm surges. Between the year 2000 and 2100 we project a very likely increase of the global average 100-year ESL of 34–76 cm under a moderate-emission-mitigation-policy scenario and of 58–172 cm under a business as usual scenario. Rising ESLs are mostly driven by thermal expansion, followed by contributions from ice mass-loss from glaciers, and ice-sheets in Greenland and Antarctica. Under these scenarios ESL rise would render a large part of the tropics exposed annually to the present-day 100-year event from 2050. By the end of this century this applies to most coastlines around the world, implying unprecedented flood risk levels unless timely adaptation measures are taken.

https://www.nature.com/articles/s41467-018-04692-w

The whole paper can be read.

[HBS Guy]

Jim Java @priscian Following Following @priscian More
Replying to @Tangomitteckel @PolAnimalAus and 48 others
There has been. PSMSL tide-gauge station data aggregated into a GMSL data set (Church & White 2011, http://dx.doi.org/10.1007/s10712-011-9119-1 …). There are significant changepoints at ~ 1934 & 2000, with most recent slope = 4.1 mm/yr. Increase in rate of SLR for each segment = +acceleration.

4.1mm/year increase in sea level according to tide gauge data. When will that accelerate again?

[HBS Guy]

Satellite altimetry shows a slower level of rise:

Climate-change–driven accelerated sea-level rise detected in the altimeter era
Satellite altimetry has shown that global mean sea level has been rising at a rate of ∼3 ± 0.4 mm/y since 1993. Using the altimeter record coupled with care...

[url]pnas.org[/url]

http://www.pnas.org/content/early/2018/02/06/1717312115

[HBS Guy]

Richard Alley on “Sea level rise, Inconvenient or Unmanageable?

https://www.youtube.com/watch?v=WE9Gqy8Yy9w

[Lols]

Two years ago, we went on an adventure to see Alaska, and much to our horror, learnt about the melting glaciers, and how rapidly they have been receding since the 1970's.
One of the rangers showed us photos she carried with her, to show us, I will try and locate those to post here to show the difference in decades how it had receded.
I just saw the latest photo of the glacier compared to mine 2 years ago

Here are my 2 photos from May 2016, compare that with a recent photo (3rd picture down), I found online.

[pinkeye]

Yes... we are watching it happen. Pretty powerless, really.

[HBS Guy]

And—idiots or cowards—are prattling of an ice age within months. Mostly on Twitter but doubtless FaceBook and YouTube but I stick to Twitter and try to point out some reality:

1. Last Maunder Grand Minimum took place during a time of depressed temperatures misname the Little Ice Age

2. The LIA was triggered by heavy vulcanism, worse than Krakatoa. We could get another such vulcanism again but single events like that impossible to predict and they cannot be counted upon!

3. A GSM sees the sun emit a bit less UV, equivalent to cooling by 0.3°C for a Maunder level GSM

4. A GSM does not remove the CO2e (CO2, CH4, N2O, CFCs etc) from the atmosphere. A GSM therefor does not stop AGW.

5. So likely no mini ice age before any GSM happens and the bit of cooling a GSM brings will be wiped out within 15 years.


ehehehehe some are not pleased, I would even go as far as to say some are peeved, by my tweets. Oh, that stops me from sleeping at night

[HBS Guy]

There are some clowns who say “No sea level rise, my beach is exactly the same” tho sea level rise so far is in millimeters and you do need a tide gauge to measure. If Antarctica keeps accelerating its melt sea level rise might soon enough become obvious even to the bare eye but by then it is too late.

[Dax]

When first in Europe back in the late 60's, saw lots of glaciers and fast flowing rivers. Last time, early this year the glaciers I saw had retreated over 2klms, most of the main rivers are almost dry in place and the Seine is almost un-navigable. IN Bavaria where my friends live, there is no longer snow in winter and some of the lakes have dried up and the snow line has retreated a long way. Saw a ski jump, which used to be snow covered and now it sits there with no snow anywhere.

Same with the Himalayas, went there last year to the same place, which sat beside a massive glacier during my first visit back in 1969. Now it has shrunk so much, you have to walk klms up the pass to see it and the area was snow covered, even in summer. Now there is no snow to be seen until you get to much higher altitudes, even in winter the snow now rarely gets to the village.

As for sea level rise, at Port Arthur on dead mans island, back in the 1870's an officer gouged a high and low water mark on one of the rock faces there. I first saw it in the 1970's and now the high water mark is under water.

[HBS Guy]

Just posted a link to your post on Twitter. Might get one or two to see sense.

Lady Lols also mentioned glacier retreat.

[Lols]

I found the photos I was shown at the Mendenhall Glacier when we visited there.I also found the online photo that the lass showed us, it was taken in 1985.
Here is a link, about the Glacier, some may find interesting reading.
[url]
https://blog.nationalgeographic.org/201 ... -and-then/[/url]







This photo was 1985



This photo compared to 2004



My current photos from 2 years ago of the surrounds, plant growth where it was once glacial, and informaiton.

[Lols]

Now I will show you photos of the Columbian Icefields in Canada.

First of all, a link or two, of course.

https://elitejetsetter.com/melting-glaciers-climate-change/

http://www.oneonta.edu/faculty/baumanpr/geosat2/Big_Melt_Down/Big_Melt_Down.htm


The photos I am putting up, are of how far the icefield has receded, from that Chalet. I was told by the locals, that the icefield used to go practically right up to the building. Look how far away it is now, and what is left looks like we landed on the barren moon!





The Chalet up closer.

[Lols]

Typo. I can't go back to edit. But one photo below is not 2004, but comparing how much glacier receded since 2004.
PS how come one cannot go back into post to edit?

[johnsmith]

You should be able to edit. The mad dutchman has probably been screwing with the settings again

tell me exactly what you want edited and I'll change it for you.

[Lols]

You should be able to edit. The mad dutchman has probably been screwing with the settings again

tell me exactly what you want edited and I'll change it for you.

Thank you John, I had noticed another time I was unable to edit, when I spelt something wrong, trouble with me, I tend to type fast and off the cuff.
I used to do shorthand and still do touch typing with all 10 fingers, and always fast!

See if it makes sense, it's the post time 13.23
And the 5th photo down, I wrote "This photo 2004" I should have put, This photo compared to 2004.

[johnsmith]

You should be able to edit. The mad dutchman has probably been screwing with the settings again

tell me exactly what you want edited and I'll change it for you.

Thank you John, I had noticed another time I was unable to edit, when I spelt something wrong, trouble with me, I tend to type fast and off the cuff.
I used to do shorthand and still do touch typing with all 10 fingers, and always fast!

See if it makes sense, it's the post time 13.23
And the 5th photo down, I wrote "This photo 2004" I should have put, This photo compared to 2004.

fixed!

there's a 30 min difference in the time stamp on my end. Where you show 13.23, I see 13.53 ......... interesting

[Lols]

That's weird, I mean, we have Daylight Savings, so I should be one hour ahead of your time in Qld. Yet, your time stamp is half hour ahead?

Sounds like Qld got half DLS

BTW, while you are in 'teaching and guiding mode', how do I put up a youtube, where it shows the picture, I can only do a url.

[johnsmith]

That's weird, I mean, we have Daylight Savings, so I should be one hour ahead of your time in Qld. Yet, your time stamp is half hour ahead?

Sounds like Qld got half DLS

BTW, while you are in 'teaching and guiding mode', how do I put up a youtube, where it shows the picture, I can only do a url.

Sorry, can't help you. Youtube never works for me.

Monks told me several times how to do it but somehow when he speaks all I hear is static

[Lols]

That's weird, I mean, we have Daylight Savings, so I should be one hour ahead of your time in Qld. Yet, your time stamp is half hour ahead?

Sounds like Qld got half DLS

BTW, while you are in 'teaching and guiding mode', how do I put up a youtube, where it shows the picture, I can only do a url.

Sorry, can't help you. Youtube never works for me.

Monks told me several times how to do it but somehow when he speaks all I hear is static

Funny when Monk tells me soon, I will have to try and decipher static for you

[Lols]

Now here is someone we ought pay close attention to! This is what he has to say.

http://www.msn.com/en-au/news/world/sir-david-attenborough-issues-dire-warning-about-climate-change/ar-BBQrXa9?li=AAgfYrC&ocid=ACERDHP15

[HBS Guy]

Posting a YouTube:

Click the youtube tab above the text window.

Paste the YouTube URL between the Youtube tags.

Delete the ‘s’ from “https://. . .”

Should be good. If not I will fix.

[Bongalong]

https://twitter.com/rahmstorf/status/1070717050430070787

[Dax]

"The rate of ocean warming today has accelerated significantly since 1991, and is increasing much faster than previously recorded, according to a new study of ocean temperature research."

https://www.abc.net.au/news/science/201 ... e/10693080

Big shock coming to human societies as the rate of ocean and air warming rapidly increases, along with the growing use of fossil fuels and dumping of human waste and plastic pollution in the oceans.

[HBS Guy]

Yup, but it snowed in Greece so we are kewling. Simplistic as that, deniers.