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Messages - Tor Bejnar

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1
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 19, 2019, 04:35:27 PM »
The 'nose' was just past Hans Island yesterday (per DMI's images) (70 km in '1 day'!), a little rounder than it was the day before, as it was slightly too big to fit past Hans Is.  The 'tail' has further broken into smaller floes.

2
Quote
If such a battery [1,000 Wh/kg] was real our emissions problems would be solved.
Maybe... If they are 4x more dense (I think that's the term) but 100x more expensive, their use will be limited (or if they are rechargeable, but only 20 times; or the charge only holds for a few hours …).  Of course, that '100x' will be whittled down to 1 - 4x in time, probably, and then "our emissions problems would be solved".

We are living in interesting times!

3
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 18, 2019, 06:48:08 PM »
The 'nose' of the largest floe to enter Nares Strait recently is going faster than its tail.  The nose section moved nearly 50 km in one day, while the tail moved 10 km less [i.e., it broke].  (The little island next to the nose, by the way, is Joe Is. [map]  Hans Is. is nearly 70 km downstream, and the channel's width between Hans Is. and the side of Judge Daly Promontory (Elsmere Is.) appears to be less than the width of the nose at its widest.  The tail, of course, is wider still.)

Edit: Floes in Kane Basin and Smith Sound moved 45-50 km between April 16 and 17 DMI images (not pictured).

4
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 17, 2019, 05:38:20 PM »
Quote
The Nares Strait is, I believe, bordered by extremely hard limestones and dolomites.
This is "true" as far as it goes. 
Here is a partial 'grab' of rock types associated with each group of formations identified on first map from Denmark (yes, lots of dolomite, some of it 'hard') [some great photographs showing examples of outcrops]:
  • ‘Ellesmere Island – Inglefield Land belt’:  used to describe occurrences of the same gneiss, supracrustal and igneous suites on both sides of Smith Sound (Dawes 1988).
  • The Thule Basin is defined by a thick sedimentary-volcanic succession.  K-Ar ages of 676 and 627 Ma
  • Palaeozoic Franklinian Basin
    • Dallas Bugt Formation: Red to purple-brown arkosic sandstones with con-glomerates form the basal strata, overlain by white to pale yellow weathering, crossbedded sandstones, and topped by finer grained sandstones interbedded with green bioturbated mudstones
    • Humboldt Formation: basal fluvial sandstones and conglomerates, are succeeded by cross-bedded, bioturbated, shallow marine clastics of tidal origin, with the upper interbedded sandstone and mudstone
    • Ryder Gletscher Group: carbonate and siliciclastic deposits:  cliff-forming dolomites, crossstratified dolomites, hard grey dolomite, grey dolomites, with some thin silty horizons, mottled lime mudstones with silty laminations and horizons, together with dolomite-filled burrows and small mounds, locally dolomitised burrowed lime mudstones and minor conglomerates with some interbeds of grey, often glauconitic, calcareous finegrained sandstones; in the south-west glauconitic sandstones and siltstones dominate, with some more resistant limestone beds, uniform and hard, locally dolomitised oolitic limestone, bedded platy lime mudstone with silty laminae, and laterally extensive beds of intraformational flat-pebble conglomerate, massive thin bedded dolomites, stromatolitic mounds, siltstones and bituminous limestones, grainstones and white, brown-weathering sandstones, cliff-forming, burrow-mottled, grey lime mudstones with subordinate intermixed stromatolitic to thrombolitic limestones, sponge mounds and flat-pebble conglomerates, shaly dolomites, laminated lime mudstones and shales with both algal and wave-formed lamination, and dolomitic sandstones. Conspicuous beds of laminated to massive anhydrite and gypsum.
    • Morris Bugt Group: cliff-forming dolomitic limestones, with one distinctive recessive argillaceous unit
    • Washington Land Group: reef-derived deposits, lime mudstones, dolomitic limestones, dolomites and resedimented limestone conglomerates, together with subsidiary siltstones and shales.
    • Peary Land Group: siltstone and sandstone turbidites

The second map is from a Geologic Map of the Arctic from Canada with a few place names added in red.  A plate-boundary transverse fault (with complications) runs through the Strait.

5
Antarctica / Re: Antarctic Icebergs
« on: April 16, 2019, 04:40:06 PM »
During this week (as of March 15), A68-A has moved 6 km northwards (measuring at the side of the ice island closest to the point just north of Larsen C Ice Shelf, and the south end has moved (rotated) about 7 km eastward (away from Larsen C).  (Image is stitched from two Polar View images [north and south].)  I'm guessing the ice island will continue its slow counterclockwise spin and will thus not get stuck south of Robertson Island, although I expect the ice to bump into the island (in 3 weeks, at the current rate).

6
Arctic sea ice / Re: Glossary ... for newbies and others
« on: April 16, 2019, 04:27:40 AM »
Just to substantiate what Sebastian wrote, see Collapse of the North American ice saddle 14,500 years ago caused widespread cooling and reduced ocean overturning circulation - Geophysical Research Letters 44(1) · December 2016 

7
Arctic sea ice / Re: Latest PIOMAS update (April 2019)
« on: April 15, 2019, 03:27:00 PM »
Image from arctischepinguin via ASI Graphs
I find it interesting that Wipneus's exponential regression has suggested a record low ASI volume below 4K km3 would occur each year since 2011.  Of these, only 2012 had a record low volume below 4K km3.  Is this the  'slow transition' at work or 'statistical noise'?  (I think only time will tell.)

 (Each of the square dot curve segments start with the projected minimum for the year following each year's minimum.  For example, following the 2018 minimum, the curve projects 2019 [dark blue square dot] to have a ASI volume about 2.7K km3 and no ice in 2024.  [The post-2018 curve is in red, not matching the blue dot, but the others all match the curve created at that time.])

8
Quote
Title: "EIA's Annual Energy Outlook 2019 projects growing oil, natural gas, renewables production"
https://www.eia.gov/todayinenergy/detail.php?id=38112
That graph, ASLR, is depressing.  Renewables need to climb 2 orders of magnitude beyond the EIA's expectations to serious displace oil & gas.  The only good news is that the EIA is likely underestimating renewables - I hope by 2 orders of magnitude!

9
The forum / Re: Suggestions
« on: April 11, 2019, 08:26:34 PM »
After following B_'s advice and having read all you want, click on the "MARK ALL MESSAGES AS READ" button, so that the 'rubbish' (should there be threads you're not interested in) doesn't sit there.

10
Developers Corner / Re: poll test
« on: April 11, 2019, 04:42:00 PM »
Don't die, Oren!  Don't do it!  Kassy has it in for you, obviously...
 :P ;D

11
Science / Re: Earthquakes and climate change
« on: April 10, 2019, 04:02:44 PM »
I don't know about the "and climate change" angle, but here is an Earthquakes of 2018 summary, posted on January 1, 2019 by Chris Rowan in Highly Allochthonous
Quote

Based on the last 50 years or so of data from the global network of seismometers, in an average year we expect around 1500 magnitude 5-6 earthquakes; about 130 magnitude 6-7 earthquakes, about a dozen magnitude 7-8 earthquakes, and maybe one event larger than magnitude 8 (earthquakes of magnitude 9 or more are much rarer beasts, with only two so far in the 21st century). 2018 boasted about 10% more M5-6 earthquakes than the long-term average, about 10% less M6-7 earthquakes, and about 20% (2-3) more M7-8 events and that one M8+ event. All this is well within the variability we see between years in the records since 1974.
...

12
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 09, 2019, 09:07:10 PM »
Thanks Uniquorn for the link.  I added an edit to my previous post.  South 'old winds' winds maxed out around 1200 hours on March 4 (at least as far as I looked) in the Lincoln Sea, and were generally from the south for a couple of days.  The ice moved north between the March 3 and March 4 Sentinel images.

And thanks for the big laugh, B_.  :)

13
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 09, 2019, 07:16:16 PM »
Quote
Is this a tidal wave reversing the flow briefly?
There are times when Lincoln Sea floes move northwards when there are strong southerly winds.  I think this happened once during the Pooh Sticks race.  (I know functionally nothing about tidal forces, and they may have been present, even dominant, during the race.  Alas, I apparently did not report my watching Windy.com wind forecasts [which I did do], and my memory of when there were south winds may be faulty.)

Edit:  looking up nullschool winds for March 3 & 4 (when D Day Ice moved northwards), there were some south winds, but mostly not very strong.

14
Arctic sea ice / Re: "Stupid" Questions :o
« on: April 09, 2019, 06:37:02 PM »
Quote
... I was wondering whether the water in the clouds came from the melting in the Arctic region, travelled South, then dropped it on the US?
Further to what Niall wrote, from my regular reading of the Weather Underground Cat6 blog, I've learned that most extreme rain and snow events in the eastern quarter or third of the USA contain moisture largely derived from the Gulf of Mexico.  Typically, a jet stream loop drops down over western states, picks up moisture and dumps it (as far west as) from Texas to Nebraska and places east and north (or the whole thing is shifted eastwards).  The air, having gone over the Rockies [rising air cools, losing its ability to hold moisture], is generally depleted of the moisture it obtained from the Pacific.  As cold air can hold less moisture than warm air, Arctic-sourced air 'never' contains as much H2O as Gulf-sourced air.  (Note this is my understanding for most "extreme events"; I'm sure there is plenty of Pacific and Arctic sourced precipitation events in the north or northeast USA and eastern Canada.)

[Note: I am not a meteorologist by any stretch of any mind.]

15
Antarctica / Re: Antarctic Icebergs
« on: April 08, 2019, 09:10:32 PM »
A68-A have move north about 12 km in 6 days, per today's PolarView (and the image above).

[Note: as 1º latitude = 110 km, the 'waist' of A68-A is about 27 km wide.]

16
Arctic sea ice / Re: What's new in the Arctic ?
« on: April 08, 2019, 01:06:32 AM »
A screen print from that presentation:

17
Arctic sea ice / Re: Are 3 dimensions better than 2?
« on: April 07, 2019, 07:12:35 AM »
1) I've been surprised how much fervor has gone into this thread.
2) I'm grateful to KK for "sticking to his guns"
3) "Are 3 dimensions better than 2?":  Better for what?

I voted for "3" because I was considering things like comparing 1980 Arctic ice health with today - the ice volume difference 'really matters'.  Like, really matters a great deal.

This doesn't mean that "2 dimensions" isn't highly significant for many aspects of Arctic climate dynamics, fairly independent of whether the ice is 2 meters thick or 10 meters thick.  Knowing only a "2 dimensions" number is certainly "better" for calculating albedo than knowing only a "3 dimensions" number.  (Does that 1,000,000 km3 cover 500,000 km2 or just 5,000 km2?)

Yes, ice that is thinner than a meter or two (and more so when thinner) is relatively transparent, allowing for solar-induced bottom melt and algae growth, and may be more likely to be rotten late in the melting season allowing a polar bear to either catch a seal or fall through and have to swim.  And then there is how waves, etc. affect thinner ice.  But all this just begs the question.  I don't think the thread's question is "Is knowing thickness better than knowing area?"

18
Antarctica / Re: Antarctic Icebergs
« on: April 03, 2019, 07:15:28 PM »
A68-A has moved since the previous post.  As of April 2, it has moved northward (NNW) (parallel to the local coast) about 30 km. It's got to go due east, then northeastwards to stay away from land.  I think the 'bluish tinged' coast due north (upper left corner) is Robertson Island.  PolarView image from 2019-04-02 [map credit]

19
The consequence of that warming is seen in Banks Island thaw slumps:  Extremes of summer climate trigger thousands of thermokarst landslides in a High Arctic environment
  Antoni G. Lewkowicz & Robert G. Way  -  Nature Communications volume 10, Article number: 1329 (2019)

Abstract:
Quote
Retrogressive thaw slumps (RTS) – landslides caused by the melt of ground ice in permafrost – have become more common in the Arctic, but the timing of this recent increase and its links to climate have not been fully established. Here we annually resolve RTS formation and longevity for Banks Island, Canada (70,000 km2) using the Google Earth Engine Timelapse dataset. We describe a 60-fold increase in numbers between 1984 and 2015 as more than 4000 RTS were initiated, primarily following four particularly warm summers. Colour change due to increased turbidity occurred in 288 lakes affected by RTS outflows and sediment accumulated in many valley floors. Modelled RTS initiation rates increased by an order of magnitude between 1906–1985 and 2006–2015, and are projected under RCP4.5 to rise to >10,000 decade−1 after 2075. These results provide additional evidence that ice-rich continuous permafrost terrain can be highly vulnerable to changing summer climate.

paper and pictures at link



20
Science / Re: Underground temperatures trends
« on: April 02, 2019, 08:52:07 PM »
A slippery slope: How climate change is reshaping the Arctic landscape
Phys.org article about study by Antoni Lewkowicz, University of Ottawa, published in Nature Communications
Quote
Increasing ground temperatures in the Arctic are indicators of global climate change, but until recently, areas of cold permafrost were thought to be relatively immune to severe impacts. A new study ... shows that areas of cold permafrost can be vulnerable to rising summer temperatures.

… recorded an astounding sixty-fold increase in the number retrogressive thaw slumps—landslides caused by the melting of the ice in the permafrost—on Banks Island over the past three decades.
...

21
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 02, 2019, 03:47:06 PM »
Evidence suggests one factor driving ice movement is sea surface height.  Certainly there are others, including tidal forces, subsurface currents and prevailing winds. 

I agree my "shows why it mostly comes" was too strongly expressed, so I'm editing my previous post.

22
Consequences / Re: Global Surface Air Temperatures
« on: March 29, 2019, 06:46:36 PM »
I shared Miki's interpretation, although when I read Klondike's question, I realized my interpretation was technically opposite what was written.  I wait with bated breath Rboyd's elucidation.

23
Consequences / Re: Decline in insect populations
« on: March 27, 2019, 09:04:03 PM »
If you want to root for a winner:  Go Bark Beetle!  ("Go Isp typographus!" sounds pretty good to ...)

Americans love a winner, so we join whatever bandwagon is around.
 :'(

24
Policy and solutions / Re: Direct Air Capture (of Carbon Dioxide)
« on: March 25, 2019, 05:01:02 PM »
Quote
… Increasing soil organic matter (in the top 30 cm) by 1% (which is quite feasible in 5-10 yrs with the right methods) increases carbon in the soil by cca 75 gigatons. That is 7 years of emissions!
Sequestering 7 years of emissions in (about) 7 years would be a great start!  When we start sequestering 10 years of emissions in 7 years, then we'll start heading to 350 ppm 'where we belong'.

Of course, I'm all for our learning how to efficiently sequester CO2 from smokestacks (which will continue to be required for steel and cement production, as far as I know).

25
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: March 23, 2019, 04:38:55 PM »
"new old ice" is a term I invented for a recent poll (although others may have invented it earlier).  As it is getting used, maybe, some day, it will belong in the ASIF glossary.  Is this definition adequate? [If the phrase 'sticks', we'll be seeing NOI soon.]

"new old ice" = year old or older 'thick' ice floes that move into an area with only very young ice (less than a few months old, so relatively thin).  This can happen in the Nares Strait during the winter or spring when the Lincoln Sea Polynya arch holds for a while, allowing the Strait to be flushed of most 'old ice' floes, then the Polynya's arch breaks and 'new old ice' enters the Strait.

26
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: March 21, 2019, 08:47:00 PM »
B_,
I noticed the recently mobilized 'rim floes' moved about 25 km between the March 19 and 20 DMI images.  From the pair of images in your gif, they move (up to) an additional 45 km between 20th and 21st. (Wow! That's fast within Lincoln Sea.)  The entire arch on the NNW side of the polynya moved about 0.3 km between March 19 and 20, and about 25 km the next day!  (At that acceleration, tomorrow … ::) )  It wasn't a 'collapse' so much as it moved along a few transverse faults.  I think the "abrupt freezing" you mention is freezing, but more, per my 'lay' interpretation, turbulence caused the brand-new ice to appear mottled-white when viewed by Sentinel radar.

28
Greenland and Arctic Circle / Re: Old ice moving through Nares Strait
« on: March 20, 2019, 05:43:23 PM »
Quote
My assumption at the time was there would be a major breakup.
Of course, As you noted, there almost was.

Quote
I ... didn't think that one little piece of ice would make [my no vote] true.
The "No" clarification you voted for in the first post included (emphasis added)
  • Quote
    the Lincoln Polynya arch breaks soon enough so that at least one floe of thick ice (much older than the two-week old ice currently in the polynya) enters Nares S. before the circled bits pass beyond Smith Sound
So, congratulations!

29
Tamino on Why you need to support Jay Inslee, even though you’d rather choose another candidate
Quote


So I suggest you throw your support 100% behind the candidate who I don’t think can get the nomination. Jay Inslee.

What??? Why would I suggest you not only support, but vigourously support the guy I think won’t even get the nomination? Let me tell you.



If you love Bernie, keep Jay in the race so when the bitch-slaps come, the only ones left standing are Jay and Bernie. If you love Elizabeth, give her the bitch-slap she desperately needs, not just to get the nomination and the presidency, but to do right by us when she does.

Whoever gets the democratic nomination, needs to hear Jay Inslee’s voice loud and clear, right on their heels.

Tamino usually makes sense.

30
Greenland and Arctic Circle / Re: Old ice moving through Nares Strait
« on: March 07, 2019, 05:20:01 PM »
These images show "Remnants" or "Rear Guard" (what should we call them?) have moved about 40 km in one day in Kane Basin (240 km to go) while "new old ice" (name?) has moved about 4 km in one day in Lincoln Sea (85 km to go).  ("One day" is difference between DMI images identified by date.) 

What a race!

31
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: March 06, 2019, 08:57:12 PM »
Game's on, it sounds like ...
but I wouldn't want to attempt ice skating on that remnant ice, given the recent post about rotten ice.

32
Greenland and Arctic Circle / Old ice moving through Nares Strait
« on: March 01, 2019, 05:04:30 PM »
Floes entering Nares Strait take between a week and two month (plus?) to go the 500 km to Baffin Bay (when the Strait is open).  The arch around the Lincoln Sea Polynya has been stable for a couple of weeks, basically, so (basically) all the mobile thick ice ("old") in the Lincoln Sea has now flushed into Nares Strait.  The last bits are circled in the image below (DMI image dated 2019-02-27). 

So, will the 'old' ice that recently entered Nares Strait get to Baffin Bay before new 'old' ice enters the Strait?

"Yes" will be correct if the current Lincoln Polynya arch holds on long enough (How long will be enough?) or a bridge forms in the Kennedy Channel above these circled bits of 'old' ice before more recently mobilized thick ice gets to the Strait during March or April 2019 [edit: and no southern bridge forms …].

"No" is split. 
  • Either the Lincoln Polynya arch breaks soon enough so that at least one floe of thick ice (much older than the two-week old ice currently in the polynya) enters Nares S. before the circled bits pass beyond Smith Sound or
  • these circled bits get stuck in Nares Strait for the rest of the winter due to the formation of an ice bridge (arch) downstream (at which point all the ice in Lincoln Sea will be 'old' enough to count as 'old'
"Maybe so" will be correct if a southern bridge holds the circled bits for 50 days or more, but a northern bridge holds back all Lincoln Sea ice until after the southern bridge breaks and all the circled bits flow into Baffin Bay.

33
Antarctica / Re: Antarctic Icebergs
« on: February 26, 2019, 09:33:16 PM »
Today's PolarView shows no (significant) breakage since the 20th (unlike before then!).

[It sure looks like a bite: teeth marks and all!]

34
Antarctica / Re: Rift in Larsen C
« on: February 25, 2019, 05:06:49 PM »
I'll probably start posting A68A images in the Antarctic Icebergs thread (after this one).  I estimate (with the assistance of a small protractor) the ice island has rotated 175º since forming.  That's quite a bite where it is (was?) grounded.  PolarView image from yesterday.

35
Extract: "... the researchers concluded that the excess oceanic heat is trapped in the Southern Ocean around the Antarctic."
Much of what ASLR posts is sobering (when I understand it).  This sentence suggests to me that Antarctic glaciers are doomed (not as if they weren't doomed previously), and like what ASLR regularly posts, there will be "more rapid climate change than expected by consensus climate science".

36
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: February 15, 2019, 07:40:33 PM »
Well, the gods choose reinvigorated movement: DMI Satellite Images yesterday and today.
I've marked three floes and added a couple of lat-longs to help with location.  (Yes, the left image is wider; the right image shows the current satellite pass with 'no data' being black.)  What was above 82ºN is now below 82ºN; what was above 81.5ºN is now at 81.5ºN; etc.

37
Quote
papers that might indicate why the Lincoln Sea/Nares is so late to freeze during recent years
These two article may offer some clues:
Nares Strait hydrography and salinity field from a 3‐year moored array
B. Rabe, A. Münchow, H. L. Johnson and H. Melling
First published: 17 July 2010  https://doi.org/10.1029/2009JC005966
extract from Abstract:
Quote
...
Data show warm salty water on the Greenland side and cold fresher water on the Ellesmere Island side, especially in the top layers. There was a clear difference in hydrographic structure between times when sea ice was drifting and when it was land fast. Ice was drifting in late summer, fall, and early winter with a strong surface‐intensified geostrophic flow in the middle of the strait. Ice was land fast in late winter, spring, and early summer, when there was a subsurface core of strong geostrophic flow adjacent to the western side of the strait. Salinity variations of about 2 psu in time and space reflect a variable freshwater outflow from the Arctic Ocean. One particularly strong pulse occurred at the end of July 2005. For several days, steeply sloping isohalines indicated strong geostrophic flow down the middle of the strait coinciding with an amplified ice export from the Arctic due to strong southward winds.

Water, Heat, and Salt Transports through Nares Strait, Ellesmere Island
H. Eric Sadler
Published on the web 14 April 2011 - Journal of the Fisheries Research Board of Canada

Abstract
Quote
Data obtained in Nares Strait are used to provide estimates of the transports of water, heat, and salt between the polar ocean and northern Baffin Bay. The annual volume export of water through Nares Strait is 2.1 × 104 km3 ± 30%, which is equivalent to a mean flow of 0.67 × 106 m3∙s−1 and which is about 15% of the total outflow of water from the polar ocean. The annual net heat input into the polar ocean due to the outflow of cold water and ice is found to be 15 × 1019 J ± 50% assuming a reference temperature of −0.1 C. This volume is about 7% of the total advective heat transport into the polar ocean. The mean annual export of salt from the polar ocean is 6.7 × 1014 kg ± 30% or about 6% of the total export. The total transports through the whole Canadian archipelago are estimated and it is shown that they are appreciable fractions of the total exchanges between the polar ocean and the world ocean.

38
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: January 26, 2019, 08:16:48 PM »
Quote
we would discuss as to whether we thought it might hang up on Hans or Franklin Islands
Ah, but it was so much fun speculating!  But even the Petermann Ice Island (2012)
didn't get suck in Nares Strait.  A floe named 'shark', reported in 2015, "got stuck for a day or so, but then shattered."

39
Permafrost / Re: Arctic Methane Release
« on: January 19, 2019, 05:37:23 PM »
A little off topic or pedantic prehaps, but ...
For those who use "ice age" to mean periods of glaciation advancement and near-peak ice coverage, know that in glaciology [i.e., "scientific"] terms, ice age implies the presence of extensive ice sheets in both northern and southern hemispheres. So by this definition, we are in the Quaternary Glaciation or Ice Age (and in an interglacial period—the Holocene—within it). We won't leave the current ice age until most (or all) of the ice fields in Greenland and Antarctica melt away.

Colloquially, of course, ice ages are interspersed with interglacial periods of time.  Although I believe Earth was slowly heading for the next glacial stage, human activities during the past 10,000 years or so (especially the last 300 and moreso, 70 years) have turned this Milankovitch Cycle on its head.  (Well, the Cycle is still operative, but (unintentional) geoengineering has overpowered the M. Cycle influences.)  And there are scientific papers out there [e.g. here] that occasionally use the "ice age = glacial stage" definition, so maybe you should just ignore me.

40
Consequences / Re: Volcanoes
« on: January 16, 2019, 06:06:45 PM »
The Yellowstone hyped story going around including a "465 mile long piece of molten rock" appears to be from 2007, such as reported by Science News for Students. Notice how "1200 sq. km." turns into "465 mile long" junk reporting?  See the image below
Quote

Over the years, the data have revealed rises and falls over various parts of the park's
landscape. These changes reflect the complicated movement of molten rock and
water underground.

Between 1923 and 1995, the terrain shifts averaged between 1 cm (0.4 inch)/year
and 1.4 cm (0.6 inch)/year. The shifts started becoming more dramatic between 2000
and 2003. The record-setting rise of land in the Yellowstone basin began in 2004.

The team's analyses suggest that a reservoir of molten rock, called a magma chamber,
lies about 10 kilometers (6 miles) below the surface of Yellowstone's central basin.
The chamber spreads out under an area of about 1,200 square kilometers (465 square
miles).

During the record-setting growth spurt, about 0.1 cubic km (0.02 cubic mile) of
molten rock flowed into the chamber. That's enough rock to fill the Louisiana
Superdome about 30 times.

Even though many volcanic eruptions, including some huge ones, have happened in
the Yellowstone region, the recent findings don't suggest that another eruption is
about to happen.

Still, the new study offers insights into the underground plumbing of Yellowstone,
says Hank Heasler, a National Park Service geologist at Yellowstone's headquarters in
Mammoth, Wyo. The findings, he says, are "very fascinating." -Emily Sohn

Study didn't end in 2007.  Here is a paper's abstract from 2010 that should really put a damper on hype:  An extraordinary episode of Yellowstone Caldera uplift, 2004–2010, from GPS and InSAR observations

Quote
Geodetic measurements of Yellowstone ground deformation from 2006 to June 2010 reveal deceleration of the recent uplift of the Yellowstone caldera following an unprecedented period of uplift that began in 2004. In 2006–2008 uplift rates decreased from 7 to 5 cm/yr and 4 to 2 cm/yr in the northern and southwest caldera, respectively, and in 2009 rates further reduced to 2 cm/yr and 0.5 cm/yr in  the same areas. Elastic‐dislocation modeling of the deformation data robustly indicates an expanding sill at ∼7–10 km depth near the top of a seismically imaged, crystallizing magma reservoir, with a 60% decrease in the volumetric expansion rate between 2006 and 2009. Reduction of hydrothermal‐volcanic recharge from beneath the northeast caldera and seismic moment release of the 2008 and 2010 large earthquake swarms are plausible mechanisms for decelerating the caldera uplift and may have influenced the change in recent caldera motion from uplift to subsidence.

41
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: January 15, 2019, 10:00:25 PM »
Quote
So, if we have the new temperatures for 30 years, some could say that the climate (on average) is the same, even that the weather is not.

Per Tamino, in his January 2nd post on 'What is Climate? Really?',
climate is not ever "just the average."
Quote
Climate is the probability density function of weather.

The catchy way I like to say it is:

Climate is the odds. Weather is the roll of the dice.
And the odds in January are never the same as the odds in July.

42
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: December 31, 2018, 07:10:21 AM »
Quote
P.S. I will be on holiday tomorrow and I will post on January 1st, 2019.
¡Happy new year!
By my calculations, 2019 starts in just under 5 hours.  Until then, Happy Old Year!

Oh yes, Arctic sea ice ... I predict we'll end the year in 2nd place.  (Unlike my vote in another thread)

43
Greenland and Arctic Circle / Re: Greenland 2018 melt season
« on: December 29, 2018, 04:50:33 PM »
Quote
Interesting? Not really.
That the end of 2018 is paralleling 2011 is interesting, I declare.   :)
If 2019 follows 2012's experience, this would bode ill for Greenland's ice as well as the ice floating on the Arctic Ocean.  (Did I make the "if" big enough?)

There have been a few recent comments on the ASIF relating to Fram Strait export, all rather speculative (other than graphs showing the fast early Greenland Sea SIE growth stalled to 'normal' growth).  Has anybody had a good look at how the current high over Greenland is affecting the sea ice off Greenland's darkest [northern] shores (including Nares and Fram Straits)?

44
Thanks, ASLR, for introducing us (me) to "Markov blankets".  It helps explain why I still drive a Prius (even if it is 17 years old).  I like that these 'things' can be numericalized, but that is above my pay-grade.

45
Antarctica / Re: PIG has calved
« on: December 19, 2018, 12:14:07 AM »

46
Policy and solutions / Re: Oil and Gas Issues
« on: December 18, 2018, 10:59:13 PM »
When was West Texas Intermediate this low?  Ah, last year.
(images from Bloomberg.com)

47
Antarctica / Re: Rift in Larsen C
« on: December 17, 2018, 06:11:58 PM »
A-68A has move about 20 km northward this past month.  I'm guessing it will escape the shoals near Bawden Ice Rise soon (if it hasn't already).

48
Arctic sea ice / Re: The 2018/2019 freezing season
« on: November 28, 2018, 06:48:06 PM »
How about this article?

Observed soil temperature trends associated with climate
change in Canada

[authors listed]; published 21 January 2011.
Quote
[1] Trends in soil temperature are important, but rarely reported, indicators of climate
change. On the basis of the soil temperature data from 30 climate stations across
Canada during 1958–2008, trends in soil temperatures at 5, 10, 20, 50, 100, and 150 cm
depths were analyzed, together with atmospheric variables, such as air temperature,
precipitation, and depth of snow on the ground, observed at the same locations. There was
a significant positive trend with soil temperatures in spring and summer means, but not
for the winter and annual means. A positive trend with time in soil temperature was
detected at about two‐thirds of the stations at all depths below 5 cm. A warming trend of
0.26–0.30°C/decade was consistently detected in spring (March–April–May) at all depths
between 1958 and 2008. The warming trend in soil temperatures was associated with
trends in air temperatures and snow cover depth over the same period. A significant
decreasing trend in snow cover depth in winter and spring was associated with increasing
air temperatures. The combined effects of the higher air temperature and reduced snow
depth probably resulted in an enhanced increasing trend in spring soil temperatures, but no
significant trends in winter soil temperatures. The thermal insulation by snow cover
appeared to play an important role in the response of soil temperatures to climate change
and must be accounted for in projecting future soil‐related impacts of climate change.


49
Consequences / Re: Places becoming less livable
« on: November 21, 2018, 06:04:46 PM »
A little here to support "Insurance companies base rates on past experience" and a little to support "Insurance companies base rates on future expectations not represented by past experience":

Climate Change Is Forcing the Insurance Industry to Recalculate
Wall Street Journal - Published Oct. 2, 2018 at 10:30 a.m. ET
Quote
Insurers are at the vanguard of a movement to put a value today on the unpredictable future of a warming planet


The effects of the planet’s slow heating are diffuse. Predictions of the fallout are imprecise, and the drivers are debated. But faced with the prospect of a warming planet, the world of business and finance is starting to put a price on climate change.

For the most part, insurers are acting on climate change by building models that aim to better estimate the impact. That leaves the industry with the tough question of how to reflect in premiums the new understandings of the underlying risk.


For most insurers, rates aren’t rising—yet. A flood of capital into the industry from pension and hedge-fund investors, driven by low interest rates, has increased competition and pushed down property-catastrophe reinsurance prices in the past decade.

And property insurance and reinsurance contracts typically last one year, so an insurer can recalibrate yearly as risks change. “Global warming may be occurring. Probably is,” says Warren Buffett, chief executive of Berkshire Hathaway Inc., which has a major reinsurance business. “But it hasn’t hurt the reinsurance industry. And people are pricing still as if it won’t, on a one-year basis.”

If reinsurance contracts covered 30 years, he says, “I’d be crazy not to” include the risks.
...
Big insurers are expanding teams of in-house climatologists, computer scientists and statisticians to redesign models to incorporate the effect of the warming earth on hailstorms, hurricanes, flooding and wildfires. Insurers such as Swiss Re Group say hurricanes like Harvey and Florence, which caused widespread flooding, could represent a more common occurrence in the coming decades.

Climate change may be gradual, but the effects are volatile, meaning a company could become exposed to a large, unexpected hit if it doesn’t understand the changing risks, says Junaid Seria, head of catastrophe-model research and development and governance at Paris-based reinsurer Scor SE.
...

50
Antarctica / Re: Rift in Larsen C
« on: November 21, 2018, 05:49:47 PM »
The Ice Island A68-A has rotated about 115º in 6 months, but the pivot end hasn't moved diddlysquat. 

The largest iceberg in the area (current, lower, image) has, in the meantime, moved about 125 km northwards, squeezing through what I'll call an ice-strait.  (1st image from a May 18 post by johnm33 [conveniently at the top of this thread's page 7]; 2nd image from PolarView on November 20.) 

I'm going to postulate, now, that intermittent grounding keeps A68-A where it is; no point is clearly 'actually' stuck in one place for any length of time.  A GIF covering multiple images might show if any spot does get stuck (becoming a fixed (if temporary) pivot point).

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