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Messages - bbr2314

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1
Arctic sea ice / Re: The 2017 melting season
« on: Today at 09:22:53 PM »
Snow cover/volume is obviously still dropping somewhat, but holy cow -- the departure from norm has never been larger as a relative % this season. We are now roughly double++ where we should be, thanks mostly to the Himalayas, and partially to the northern tier of Russia. The Himalayas may endure the entirety of the melt season IMO!




It should also be noted that North American volume has nosedived from way above average to normal this month. While this is hardly unprecedented, the sheer cliff we have seen will amount to ~700KM3 of volume by the end of the month. Seasonal discharge is normally quite slower, and also happens earlier in the season than this year in most years, so this will have some substantial impact on the NATL, or perhaps already is, given how cold SSTs are off Quebec/Newfoundland (and the implications on land were clear given the massive floods we saw in Quebec). How much more volume will it take before the impacts escalate even further, and how much farther down the line til that happens? It could feasibly occur next melt season...



What was the volume lost by Lake Agassiz during discharge?

Finally, it should be noted that given the cliff seen in NAmerica this past month, we could feasibly see something similar occur across the Himalayas during the summer. Whether it happens or not remains to be seen, but if it does, that would portend epic flooding across the Indus Valley and Pakistan (IMO).



2
Arctic sea ice / Re: Latest PIOMAS update (June)
« on: Today at 09:03:02 PM »
The decline of ice in the Pacific and the cool period in the area near the pole this May are a function of the weather. At winter's end in the Arctic the polar vortex was displaced towards the Barents and Kara seas.

If this pattern persists we will see a strong dipole develop with a strong transpolar drift. Hopefully, it won't be as persistent as 2007. Right now the snow cover pattern is supporting the persistence of warmth in the Beaufort sea and cold on the Atlantic side of the pole.
Atlantic SSTs are far colder than any year since/including 2012 (based on HYCOM maps), at least the far NW ATL. The heat is displaced toward Europe and also N of Scandinavia. The contrast with recent years is quite extreme, and would seem to indicate severe disruptions of whatever previous influence the Gulf Stream had SE of Newfoundland.

3
Arctic sea ice / Re: The 2017 melting season
« on: May 17, 2017, 08:53:51 PM »
Most of the ice in the Hudson bay, Labrador sea Bay, The ice on the coast of Greenland south of the Denmark Strait has a blueish tinge on Worldview from the recent high temperatures. It wouldn't surprise if they melt out quickly now, particularly considering the warmth and rain predicted over the next week.
I agree re: blue-ish tinge, but it is also quite thick -- moreso than in most recent years. Combined with the low SSTs in the vicinity/import from Nares, I think it will prove surprisingly resilient, but I could definitely be wrong!

4
Consequences / Re: Wildfires
« on: May 17, 2017, 08:45:06 PM »
The entire Russian district of Siberia is under an official state of emergency.  It is only mid-may.

https://watchers.news/2017/04/29/massive-wildfire-engulfs-bubnovka-siberia-declares-state-of-emergency/
I don't want to say it with certainty, but I suspect this is being exacerbated by compounding year over year losses of permafrost. Winter doesn't help the situation either, with snowfall anomalies wayyyyyy above normal insulating the ground from cooling off, while every subsequent summer allows more heat to accumulate.

5
Arctic sea ice / Re: The 2017 melting season
« on: May 17, 2017, 08:19:39 PM »
HYCOM may have many issues but I think one front where it is particularly useful is in comparing sea surface temperatures.

https://www7320.nrlssc.navy.mil/hycomARC/navo/arc_list_arcticsst.html

A few things are interesting to note comparing this year with last year and 2012/others --

1) The tongue of cold SSTs southeast of Newfoundland is more prominent and colder than any recent year besides 2014. Compared to 2012, the change is particularly dramatic. Temperatures immediately SE of Greenland have also decreased this year.

2) Despite this cold in the NW Atlantic, there is a strong area of warmth comprising the Gulf Stream, appearing warmer than usual and extending all the way to the NW of the UK/Scandinavia.

3) On the Pacific side, things are colder than they have been in recent years where the ridiculously resilient ridge had formerly been residing, west of the Rockies.

4) Elsewhere in the Pacific, especially in Barents/Okhotsk, things are *substantially* warmer than normal. In fact, Okhotsk is an order of magnitude warmer than any other year in recent history, and Barents is similar.

I suspect the above will contribute to Pacific-driven warmth melting the Arctic this year. As the extent/area maps already show, we are seeing substantial melt beginning along the coastlines of Alaska and NE Siberia. I expect this will continue as the heating of Okhotsk/Barents much earlier than normal (due to their possibly record-early dearth of sea ice) means that storms approaching from this direction will have much more insolation to take advantage of, and that heat will ultimately be deposited/resolved over the Arctic Ocean -- first Chuchki, Beaufort, ESS, and then the CAB.

While the above isn't too different from the story of the worst years we've seen, it is going to be occurring far earlier than ever before, and impacting an Arctic Basin where thicknesses are thinner than ever before, particularly over the Beaufort Gyre, which has no ice in excess of 2.5M in thickness (contrary to even last year, where 4M+ ice abounded). This means that we may see melt-out approaching the CAB a month or so before years like 2012, which greatly ups the chances of a blue Arctic this year.

The SST changes over the Atlantic would also seem to lend themselves to the potential for enhanced LPs/heat flux over Greenland and the FRAM/et al as the melt season progresses, given the higher SSTs than usual NW of the UK/Scandinavia. The question is when this begins to manifest -- the combination of LPs taking advantage of the warm Pacific SSTs should encourage blocking highs over that sector of the Arctic, and as those get stronger and stronger as more heat accumulates through NHEM summer, I wonder if the strengthening gradient between hot/cold over the NW ATL will favor severe cyclonic activity over Baffin/FRAM/Kara, with the contrast between PAC/ATL perhaps worsening conditions beyond any year we have seen so far.

This also has a few implications for melt season IMO -- we are going to have a sledgehammer impact the ice that normally takes the entirety of summer to thaw/melt, so that may go early, but it still may go relatively slowly. Though it will most definitely go.

On the flipside, the cold Atlantic SSTs and remaining thick ice in Baffin/Hudson will also melt out anyways, but it could easily hold on a month+ longer than normal (IMO). This means that the cliff induced by melt-out of that ice that normally comes in June may come in late July/early August -- holding up area/extent to only slightly lower than normal numbers before a gut-punch comes as all the ice that was going to melt out anyways does so quite rapidly.

Baffin ice could also hold on longer than normal due to the massive export imminent/ongoing through Nares, which is some of the thickest ice in the basin & multi-year to boot. Perhaps some of this makes it through the summer and drifts all the way down past Quebec, jump-starting the freezing season more rapidly than normal for the banks off Newfoundland even?

6
Arctic sea ice / Re: The 2017 melting season
« on: May 16, 2017, 06:58:31 PM »
Cold air was displaced to northern Europe and southern Canada but overall the NH was pretty warm for the last 30 days. Weak trade winds have led to a warm up of the tropical and subtropical waters of the NH. It has been very warm in north Africa.

The final collapse of the stratospheric polar vortex displaced the cold air towards Murmansk.

The net effect is to enhance the dipole that blows ice towards the Fram strait
Will be interesting to see whether Hudson Bay holds on longer than usual this year, ice seems to be holding up well compared to recent years and the last month of anomalies certainly didn't hurt its potential to endure the summer heat.

7
Arctic sea ice / Re: The 2017 melting season
« on: May 15, 2017, 04:07:48 AM »
The upcoming pattern being forecast by the EPS and GEFS (ensemble means of the GFS and ECMWF) are disastrous starting at D6. The CFSv2 has been hinting at a strong +AD type pattern at this time period for a while, but now the operational medium range models are on board as well. If these verify, it would serve to jump start the melting season and generate lots of late May melt ponding.

If DMI and HYCOM are correct the AK/Pac/eastern Asian sides of the Arctic should all see wide areas of open water by the end of the month, and by the 20th, everything under 80N on those sides is also going to begin fracturing into oblivion.

Meanwhile, Nares is already actively transporting out some of the thickest ice in the CAB.



Some of the models are beginning to show a surge of cyclonic activity affecting the Asian peripheral seas as well, if we see anything substantial impact Kara/surrounds it could result in a sudden loss of the relatively thin ice over most of that area/the ice N of Svalbard. I would suspect as open water begins increasing along the Siberian coastline, the thermal loading of the Arctic will allow just that to occur, though it may take another few weeks.

8
Arctic sea ice / Re: The 2017 melting season
« on: May 10, 2017, 07:31:57 PM »
SSA and SSTAs seem pretty high in Chukchi sea.
How will this impact that area as the season progresses?
Earlier melt of Pac/Asian peripheral sea ice than ever before, enhanced transport of ATL ice out of FRAM, enhanced CAA garlic press -- we very well may see a Blue Arctic this autumn.

9
Arctic sea ice / Re: The 2017 melting season
« on: May 08, 2017, 02:57:38 PM »
Hyperion's posts/analysis have been very useful in this regard, as have others, in showing that the warming/increasingly ice-free Arctic is causing massive plumes of moisture, which inevitably intersect with mountaintops that ordinarily are snow-free by this time due to lack of moisture, above other factors.

Just a note,

The global Atmospheric Water Vapor maps indicate that the water vapor is coming from the tropics, that atmospheric water vapor has remained elevated since EL Nino and that circulation effects may by impacted by sea ice but, more likely, sea ice is being affected by global atmospheric circulation effects.
Perhaps would be better worded to say that degradation of sea ice is allowing massive plumes of moisture to push increasingly poleward, crossing/impacting mid-latitude mountain ranges in the process. As we head towards ice-free, the Arctic Ocean should also begin sustaining/reinforcing these moisture plumes, though that is still a few months out.

10
Arctic sea ice / Re: The 2017 melting season
« on: May 08, 2017, 07:24:32 AM »
There is something seriously disturbing now appearing on the long-range models. The Canadian/EURO seem to do a better job vs. the GFS, which seems (IMO, and per others here) to reduce snowfall on-ground prematurely.

The models are now showing extremely severe cold anomalies appearing across many mountainous mid-latitude regions -- on the order of 20C below normal. Heavy snowfalls are now being projected D8-10 across much of mountainous Europe and the Rockies, while snows continue into Quebec and the interior Northeast. The Himalayas also remain extraordinarily cold, and in each of these regions I suspect it is primarily due to the lingering ++++volume of snow, which continues to be deposited in very anomalous amounts.

As the sea ice continues to linger/set new record lows in terms of volume, this would seem to be directly correlated to the propagation of polar lows towards the mid-latitudes instead of the Arctic; indeed, mountainous mid-latitude regions may have a better shot at both retaining and generating cold air, as long as they are snow-covered, which depends on high enough atmospheric moisture content.

Hyperion's posts/analysis have been very useful in this regard, as have others, in showing that the warming/increasingly ice-free Arctic is causing massive plumes of moisture, which inevitably intersect with mountaintops that ordinarily are snow-free by this time due to lack of moisture, above other factors. If moisture continues to increase, as seems likely, this seems to present a "looks like a duck, talks like a duck, it's a duck" argument re: causation of abrupt ice ages.











What does this have to do with sea ice? With +++snowfall/cover across the mid-latitudes relative to normal, I anticipate it will favor very low 500mb height anomalies over the affected regions. This should have the effect of encouraging equator->pole heat transport as vast plumes of heat are lofted over the negative height anomalies, directly impacting the Arctic in the process as we are already seeing.

Another key thing to note re: elevation-based snowfall is that leaves the polar-adjacent landmasses much more vulnerable to losing their snowmass, as for the most part they are *not* elevated. The downsloping effect over the northern tier of Alaska, Canada, and Russia will exacerbate the ice loss in peripheral seas adjacent to these regions, as we are already seeing occur, and the outcome come September is likely to be quite bleak IMO.

11
Arctic sea ice / Re: The 2017 melting season
« on: May 05, 2017, 07:14:24 PM »
TB, the red patch in the Beafort shown in your 2016 image as ~4m thick, known as Big Block, completely melted at the very end of the melting season. And in general, leftover extent was much smaller than shown in that image. So I would say 2.5m thick ice is also surely vulnerable, depending on latitude and mobility, possibly even thicker than that. If you put the May map side by side with the same map at the Sep min, some more insights might arise.
What I've been harping on and what is evident in that comparison is the easy access open water will have on the Pacific side to the heart of the Arctic this year. You can see that while thickness was bad along the immediate coast last year, this year, it is a much larger bite out of the pack that extends much further into its heart. Very, very bad.

12
Arctic sea ice / Re: The 2017 melting season
« on: May 04, 2017, 06:41:53 PM »
This one caught my eye in one of nearby threads, posted yesterday:



Is this real? Can there be any much error?

It is most definitely real and also explains why volume is at a record low.

Models are now emphasizing a sustained period of warmth across the Pacific side of the Arctic beginning shortly and extending/worsening indefinitely.

I have already mentioned how I believe this is connected to the very early melt of Bering/Okhotsk, and it appears that the ramifications of ^ will result in the same occurring over Chuchki/ESS, and potentially the Beaufort as well.

If you look at HYCOM/PIOMAS it is apparent that while there is a slight barrier of 2-3M ridged ice between Beaufort and Pacific inflows, this is totally absent along the Chuchki front. Last year saw some extremely thick ice in between the inflows & both peripheral seas, something we are almost lacking completely this year.

If we see sustained warmth as the models are now indicating, the ramifications will be quite dire for several reasons.

1) With the Bering already mostly ice-free, there is vastly heightened potential for Pacific inflows to push much farther into the Arctic than they ever have before. On PIOMAS the only year with ice thicknesses anywhere near 2017's in the aforementioned regions appears to be 2011.

2) With ice thicknesses already at record lows in the Chuchki/ESS, any heat intrusions have the potential to rapidly melt the little amounts of ice that currently exist. HYCOM and satellite already show areas of low concentration in these peripheral seas. If we see extended heat through to 6/1, we may be dealing with large portions of these areas taking up an unprecedented amount of solar insolation at the peak of summertime. Normally this energy would go into melting the ice, not warming up the water.

3) Increased Pacific inflow is likely to destroy the structural integrity (or whatever minimal amount remains) across Beaufort/the CAA. Beaufort's ice thickness is again at unprecedented low levels, though somewhat thicker than Chuchki/ESS. But it could and IMO likely will melt out completely this year, and as Chuchki/ESS melt out, the increasing areas of open water will likely lend themselves to heat intrusions of mounting substance from several perspectives.

4) The above directly relates to the fate of the ice in the CAA in that the fracturing of the Beaufort/ice adjacent to the CAA will allow the garlic press to activate *way* ahead of when it had in recent years. This means we could see much more freshwater and thick ice flush into Baffin Bay and, ultimately, this would disrupt AMOC circulation to a greater extent than we have seen in recent years.

5) Finally, the increased open water in peripheral seas during the height of NHEM insolation means that as cyclones drift north from Siberia during the summertime, they will likely intensify beyond levels previously seen, enhancing export out of the FRAM, at least while there is still ice to export. Besides enhancing export, heat transport into the Arctic is also likely to continue increasing. And as we enter late July and August, the sheer area of the Arctic Ocean that will be ice-free means that we are likely to see GACs far worse than the repeat events of last summer.

If the above holds to be true, last year may in fact have been the last instance of meaningful September sea ice. The PIOMAS maps are absolutely terrifying, not just because of the record-low volume, but because of where the worst anomalies are situated and what they entail for solar insolation during the months of June, July, and August. The situation is likely to result in superficial gains in Atlantic ice extent (as well as substantial freshwater export) continuing for a month or two, but this will all melt out by September anyways.


13
Arctic sea ice / Re: The 2017 melting season
« on: May 04, 2017, 12:27:32 AM »
To roll foward FoW's post:







Some strong hints at a +DA pattern as the record-setting NAO block retrogrades into central and northwestern Canada. Pretty bad timing if that's the case as it could easily initiate early surface melting if temperature advection is strong enough.

Equally important in these maps is the ending of winter across NE Asia (Siberia, etc). I think the GFS has problems with reducing snowcover prematurely, but even with that issue, the other models also seem to be hinting at ridging developing into Central Asia, which would likely begin pumping heat into/across Siberia.

As the Siberian snowpack gets smoked into oblivion, it becomes much easier for ridging to pump heat directly into the Arctic, without any sort of moderation. This is similar to what's about to happen over Okhotsk/Bering, but the sheer scale/size of Siberia means that once it goes snow-free, the warmth's ability to attack directly into the Arctic becomes much greater. I would think this is why the anomalies begin spiking fairly dramatically towards D10+.

While snow depth remains fairly high in areas adjacent to the peripheral seas, southern reaches of Siberia are currently at a major loss in terms of extent, and with area already plunging over there, it should only be a matter of time before those blues evaporate into the atmosphere & are deposited over the Arctic as rain.

Areas of snowcover I could see persisting abnormally long include Quebec and the northern reaches of Scandinavia/far NW Russia, as these seem to be the favored dumping grounds for the cold up north given its inability to remain in place this year (and also, the heat ridging that I believe will soon predominate over the Pac/Asian side of the Arctic should favor lingering cold in these areas). But since the ice near these areas is first-year and will melt anyways, that does little good.

It should also be noted that Iceland is very red on these maps as well, perhaps it is not exactly chicken and egg re: NATL blocking, but I would imagine an anomalously early snow-free Iceland certainly does not hurt ridging potential for the NATL/Greenland.

Lastly, it should be noted that we have bits of green over very low-latitude areas, including Japan, Iran, Turkey, SE Europe, and the southern Rockies. All of these regions are quite elevated, and while they will ultimately lose snowcover, this seems to be yet another indicator of the Arctic's increasing inability to retain cold, and consequent late-season snowfall in areas where it should not be happening. We have now seen killing snows & frosts damage crops across much of southern Europe as well as the western Great Plains of the US -- it is not the raw warming that will do civilization in, but the increasingly rapid and as-yet-unpredictable swings between anomalous heat and cold weather.


14
Arctic sea ice / Re: The 2017 melting season
« on: May 03, 2017, 08:43:33 PM »
I think it is important to note that the ice in Okhotsk/Bering is seemingly at record lows at the moment.

Last year's Beaufort melt was very bad, but it was not catastrophic in the way that this year could be, due to the gyre pushing relatively thick ice into the pathway of the Bering Strait, which stalled open water reaching into the Pacific side of the Arctic for at least a few weeks as that ice had to melt.

This year, we don't have that luxury. The lack of ice in Okhotsk/Bering is also threatening in that its usual persistence tempers the airmasses advected north during the melt season (at least, through June or so). With most of the ice already gone or set to vanish by 5/15, we should see the melt season begin much sooner than normal across the Siberian Seas, and potentially Beaufort as well.

On the flip side, this should keep relative cold along the Atlantic-facing ice (Baffin, Barentz, Hudson). But this will only add to transport into these regions, which will likely melt out by summer's end anyways, IMO setting us up for a record low situation come September. If any region is looking somewhat solid, I would say it is the CAA, though this will also be prone to flushing as the ice structure disintegrates and the garlic press begins to activate.

15
Arctic sea ice / Re: The 2017 melting season
« on: May 01, 2017, 01:04:35 AM »
Looks like we are about to see a pre-cursor to the CAA garlic press commencing in full force. DMI and HYCOM show the thickest ice breaking off of the CAA with potential breakage of the Lincoln Sea ice bridge as well... once this happens it should allow significantly more impact from any cyclones on the ice, and subsequent movement of the CAA ice to the south.

16
Arctic sea ice / Re: The Fast Transition
« on: April 30, 2017, 10:25:03 PM »
Should note how snowy the Rockies currently are as well, most all stations are WAY above normal in terms of volume. I suspect this is directly related to the record-low sea ice volume.


17
Arctic sea ice / Re: The Fast Transition
« on: April 30, 2017, 10:14:39 PM »
I agree with Hyperion here, plus once the ice is shattered it will bleed out through the CAA taking a huge reserve of fresh water with it. Then we'll face accelerated base water exiting through Fram as evaporation and freezing in their turn contribute increasing amounts of dense saline water to the halocline, creating in it's turn to an increase of Atlantic water ingress.
I am also in agreement.

Perhaps Sandy was the first instance of such a storm? We've seen several close glances the past few years as well, but perhaps the record minimum in 2012 was directly to blame on the hybrid-monster situation.

If that is the case, and we see another record low this year, as all indicators seem to be pointing towards, perhaps we will see an even worse event this fall?

18
Arctic sea ice / Re: The Fast Transition
« on: April 28, 2017, 08:47:18 PM »
. Despite the record or near-record warmth so far this year, spring extent numbers are now above normal, and volume is possibly at a record at the moment

Please examine your second graph much more  closely. In particular:

1. Mean dates are from 1998-2011.The last graph I posted clearly show that the 1998-2016 mean  is much more lower than 50 years ago. Above 1 sd of this young mean probably means below a mean that included older data.

2. Extent is now slightly above 1sd of  1998-2011 mean and for the past week it has been so. But since the inflection point extent hugged the lower end of the variability for most of the end of winter and beginning of spring. In a cumulative manner, extent is running low, not high.

When you add this two the apparent big feedback is nothing but a whimper.


It wouldn't surprise me if the volume of snow reached record highs. There is much more water in the air,  but it doesn't have staying power.


While the trend has been downwards in recent decades, I suspect we may be at a sort of inflection point at the moment, and it is premature to expect the downward trend to continue given the signal emerging this year/the past few, concurrent with record-low sea ice

 See the years 1968 and 1989 on the Spring NH snow extent. As I hope you see, it is not unprecedented to have big drops followed by big recoveries. The problem is that the recoveries are much smaller in the recent years. There is no reason to think that trend will reverse.


Granted, after the ice disappears almost anything can happen. The Earth could freaking snowball for all we know. If that happens, then sure the ice might return, but it won't matter to any of us.
Those graphs are valuable, but I wish they had volume as well. Alas!

19
Arctic sea ice / Re: The Fast Transition
« on: April 28, 2017, 08:31:19 PM »
bbr2314 - your second graph would seem to support a "more snow area in the winter but melts faster in the spring" hypothesis. Will be interesting to see what happens to snow extent in the next few weeks.

If there is greater snow cover on Northern Hemisphere land in Fall/Winter that should tend to reduce temperatures (although insulating the ground beneath). With increased cloudiness over the open Arctic Ocean in the darkness of Fall/Winter, it will tend to stay warmer. The overall effect may be to reduce the temperature differential between the Arctic and the rest of the Northern Hemisphere further?
We were relatively low on extent, but numbers have now come up, so I would say for this spring we are about average in terms of overall extent, but possibly at a record high in terms of its snow-water-equivalent.

I think the only regions where ground insulation comes into meaningful play are those with permafrost. This is another warming feedback for the very far northern tier (Siberia, etc), but for the vast majority of the NHEM that is not covered in permafrost, I think it is a net reduction for temps. Still, this supports warmer temps in the Arctic itself due to the feedbacks you mentioned (clouds, and warming ground in permafrost areas).

I still believe we will soon hit a tipping point where the ocean is warm/ice-free enough to really rev up fall/winter snowfall numbers, enough so that we see snowpack begin enduring more and more readily into spring and early summer. We are already seeing this manifest in the anomalously high snow-volume numbers seen this year. How much more snowcover needs to build in fall/winter for extent to follow suit in the spring? I do not think we need that much more for this to begin occurring, though I could obviously be wrong (and the general consensus among most posters here is that I am wrong, so there's that too).

Nevertheless, the relationship between NHEM snow volume and arctic sea ice volume seems to have an inverse correlation, and as we continue seeing new lows throughout the year, it will be very interesting to see whether this relationship strengthens or weakens -- my bet is on the former.

20
Arctic sea ice / Re: The Fast Transition
« on: April 28, 2017, 07:18:47 PM »
There is a negative feedback mechanism that will likely prevent any runaway scenario in that more open ocean leads to more moisture in the air which leads to more snow cover on the surrounding continents. More snow covers leads to later/colder spring air temps (through increased albedo over land) and thus to a greater chance of more ice surviving into the following year.


That feedback mechanism does not exist. While indeed more snow is forming during fall and winter (when the sun doesn't shine) during Spring it is melting faster than ever resulting in less extent when the sun is shining.
I don't think we have enough data to determine whether it exists or not just yet. Despite the record or near-record warmth so far this year, spring extent numbers are now above normal, and volume is possibly at a record at the moment. While the trend has been downwards in recent decades, I suspect we may be at a sort of inflection point at the moment, and it is premature to expect the downward trend to continue given the signal emerging this year/the past few, concurrent with record-low sea ice #s.





I suspect it will be another five years or so before the volume trend amplifies enough that extent begins to follow a similar deviation above the norm. But I could easily be wrong!

21
Arctic sea ice / Re: The 2017 melting season
« on: April 26, 2017, 12:03:33 AM »
Snow extent back up to +1SD, surprisingly... and volume is just beyond!




22
It would be very difficult to expect an aerosol forcing component in the historical trend based on agricultural cycles.

however

there is more than a number of papers that have determined that the late period cycle could be driven by natural variability without a strong aerosol cloud effect in the tropics.

for example:

http://onlinelibrary.wiley.com/doi/10.1002/2016GL071337/abstract

we conclude that models need external forcing to explain the magnitude, timing, and apparent multidecadal frequency of the observed twentieth century AMO variability.


Well, aerosols would not have been the primary driver initially, it would have been albedo changes (forest -> cropland over the Middle East, Eastern Asia, Southern Europe, and parts of the Americas).

Perhaps slash and burn techniques would have contributed some token amount of aerosols, but that does not mean that temperature trends/climactic variability were not impacted, creating the initial see-saw mechanism that persists to this day.

I would think that aerosols further amplified the existing changes as primitive industrialization began ~4000-3000BC (look at the Pyramids!) with corresponding heavy industry that was very inefficient in terms of raw materials -> output (which pushed large amounts of aerosols into the atmosphere). This peaked with the Romans & Chinese in the first millennium AD, with those numbers only reached again ~1800-1850. While raw output may have been higher post-1800, emissions were still roughly equivalent until about 200 years ago due to the dirtiness of industry way back when.

23
u know bbr that was my first thought too but realized it would be impossible to show that the economic cycle drove the emission trend or if the temperature trend drove the economic cycle.  (I suspect the former)  It is interesting though that the KWave has shifted to a longer period than in the 1800s ( it used to be a 50 year cycle.
I would think it is most definitely that economic cycles drive emission trends. I think this began with the dawn of agriculture, when albedo feedbacks (as well as primitive emissions) would have started the see-saw that continues to this day, where economic prosperity drives climactic changes, which demand innovation & economic re-organization (i.e. periods of recession/depression), and then the cycle continues.

24
for example, in the first graph, the 1920 line is actually 1917 (if you apply a grid function to determine the actual date instead of eyeballing it like I did)  and the 1935 graph line could reasonably be shifted to 1942 since this was when the emissions actually started to increase again (driving the shift in the AMO graph).

And since Mann et all detected a 70 yr cycle going back 400 years are you really serious or just so tied into a pet theory that you can't see the silliness of it??

Besides how is it we don't see a change when MT Agung or MT Pinatubo erupted?  Is this only forced by anthropogenic aerosols and ignores natural emissions??  Funny how the atoms and molecules must be zipping around with little origin tags on them.
https://en.wikipedia.org/wiki/Kondratiev_wave

25
the spike in global wood fuel in the post world war I recession and 1920 depression indicates that, from an energy use perspective, its effects was much greater than the great depression from an aerosols perspective.  The sudden change of aerosol emissions driven by economic cycles is the only variable that has the potential to impact the global circulation patterns on such a short time scale.  I made a hypothesis that the shifts happened before the great depression (in the 1920's) and I was able to find out that indeed, the aerosol emission shift actually happened during that time - as opposed to what I had believed previously.

Also that the shift in PDO to positive indicated that there was significant forcing pent up in the system, which causes a sudden shift in atmospheric and ocean circulations when the cork is released by suddenly cutting aerosol emissions.  In a Dynamic Fluid system when this happens there is always an impact that swings far beyond equilibrium.  Hence a definitive signal can be derived from the period.  AND since recent studies all indicate aerosol impacts to these circulation metrics (AMO, AMOC, PDO, NAO) it can be reasonably deduced that a significant part of what was considered 'natural variability' at the time was actually driven by regional SO2 emissions reductions and GHG forcing -- contrary to the current assumption that we cannot determine the cause of early period warming by the IPCC.
the more we delve into this the more sense it makes (IMO) and I *highly hugely wish* that we had actual funding to explore this area of research further.

re: nuclear weapons testing, i would think that if there was any primary effect it would've been on ozone? besides that, the weapons being tested were being detonated in regions remote/barren enough to avoid substantial fallout in the vast majority of cases. i'm sure a Siberian forest or two went up in smoke thanks to the Russians, but beyond that, the "nuclear winter" aspect following any war is due to the cities/etc burning and being thrown into the atmosphere. with testing, this was not a goal or an outcome.

26
Arctic sea ice / Re: The 2017 melting season
« on: April 19, 2017, 10:33:24 PM »
Seems to be led by NE Siberia, Quebec, and the Western Himalayas:

Keep an eye on those Western Himalayas, especially during summer.  ;)
I will! I think there is definitely a possibility you are correct re: error, but I have also found an abundance of writing that signals the Western Himalayas (and Karakorum specifically) reversed the trends of glacial recession sometime around 2000, with mass-loss halted entirely and even reversed in the period 2000-2010. If that is the case, then we are building on snowcover year over year in some of these spots, which could also be an explanation for the abundance of purples. Can't wait to read more research into this phenomenon one way or the other.

27
Arctic sea ice / Re: The 2017 melting season
« on: April 19, 2017, 05:23:52 PM »
NH snow cover shooting up now (mostly due to snowfall in Canada):

Volume-wise, the uptick has also been singificant, wayyyy beyond +1SD at this point, that is a huge anomaly!



Seems to be led by NE Siberia, Quebec, and the Western Himalayas:


28
Consequences / Re: Global Surface Air Temperatures
« on: April 19, 2017, 12:44:37 AM »
Does anyone else find it slightly disturbing that our last episode of sustained major warming culminated in 1945, the same year that saw the peak of global slaughter and the first use of nuclear weapons? I hope it isn't a precedent for what's to come in the next few years...

Side note: would it be possible to compare the above temperature graph to annual global GDP growth? I strongly suspect there is a substantial correlation.

29
This thread is dead

The top two authors on this paper both believe that the FIRST < 1X10^6 km^2 SIE September minimum will happen around 2065.  Or, this is what they have said publicly.  Whether they ACTUALLY believe this is not clear.

The difference between SIE effectively ice free in 2020-ish vs. 2060-ish is measured in the balance of millions of human lives.

There is no excuse for being this far removed from reality.  Either they are completely incompetent, unaware, overconfident in their supposed knowledge, don't care or are a fifth column element working against the greater good intentionally.

In any case these errors will soon be written in stone as one of the greatest failures in human history.

if there is anyone left to remember.

https://www.youtube.com/watch?v=NmL4t8TclGU
I deleted my earlier comment but I am 100% in agreement with you on this. I think that discussion for discussion's sake does nothing to improve actual discourse if it lacks substance or meaning. I also wonder if any groups backing fossil fuels may be funding the "research" presented in this thread.

30
Arctic sea ice / Re: The 2017 melting season
« on: April 17, 2017, 03:36:02 AM »
The ice is heating up quickly now, should probably be another two weeks or so until we see large parts begin to break 0C on a daily basis.


31
jai mitchell  +1

I've been meaning to say this for a while, and this is offtopic, but your coal/aerosols/sst argument is a courageous one. You are saying that shutting down Coal plants causes short term global warming.  I bet you get a lot of flak for that.

When you first started to state that point, I was suspicious of you because it sounded like a very convenient argument for a climate change denier to take advantage of. But then as you refined the argument and presented more and more evidence I realized that my suspicions of your argument  were nothing but my own personal bias. You are probably right and your argument is very important if coal is going to be phased out.

For example phasing out coal plants during warm cycles of the planet will compound the problems of the warming. Closing them during cool earth cycles will reduce the impact of the short term warming at the cost of maintaining the Earth at a higher temperatures for longer.

This might be an important consideration that is impossible to talk about because of the nature of the debate.

thanks Arch. 

you know the real issue here is that a significant (possibly VERY significant) portion of the cooling impact of upper troposphere SO2 is simply not addressed in the climate models since the physical interactions are not well known. 

With only a modest addition of these impacts and with the recently documented impacts to PDO, AMO and related atmospheric circulation patterns (based on regional emissions/reduction trends in the modern record) much of the supposed variability is washed out INCLUDING the early warming phase in the 1930s that is currently NOT being 100% assigned to anthropogenic activity (just like the intensity of PDO/AMO was also missing significant anthropogenic components).

However some interesting things happen when you work from this assumption that SO2 impacts are severely understated.

1.  The Ruddiman early agriculture hypothesis is proven correct
2.  Arctic sea ice is going to disappear in the next few years (summer minimum)
3.  ECS is closer to 5.5K/2X CO2
4.  we have locked in +3.5C at current atmospheric abundances
5.  We have to start right away with a WWII scale mobilization effort to radically eliminate all fossil fuel consumption in the next 10 years AND begin large scale BEECS/Biochar/Regenerative Agriculture to offset carbon cycle emissions to prevent going over +4C and possibly losing global modernity.
I wonder if the global recession beginning in 1929 could be to blame for the spike in Arctic temperatures? Similar to what we are seeing as China winds down its dirtiest pollutants, the "shroud" produced by industry during the roaring 20s would've rapidly been reduced as GDP sputtered by double digits on an annual basis. Of course, wartime efforts beginning in the late 30s revved economies back up in many regions, but I wonder if the 7-8 year period of stagnation and decline could've been a contributing factor to the loss in sea ice, adding a few tenths of a degree to global temps overall before the economy came roaring back to life (along with dirtier industry emitting SO2).

32
Arctic sea ice / Re: The 2017 melting season
« on: April 07, 2017, 04:20:44 AM »
The Beaufort. April 3rd-6th


33
Arctic sea ice / Re: The 2017 melting season
« on: April 01, 2017, 02:43:59 AM »
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...
i think record volume is due to increasingly open arctic ocean (i.e. record low sea ice volume directly translates into record high NHEM snowpack volume), though i agree that the warm ground insulation is going to be a factor across the permafrost areas that continue to warm/melt (mostly Siberia). this is not the case in Quebec though.

i think that we will definitely see a plunge in overall extent and may end up with record overall lows but on the flipside, the situation re: sea ice may favor extended cover vs. normal in NE Siberia and especially in Quebec. this is because as we see less ice in the Arctic and as it melts out earlier, the first-year ice in Hudson Bay is likelier to outlive the ice further to the N, which (IMO) is likely to favor persistent cold air over the relatively lower-latitude areas of SE/Central Canada.

will be very interesting to watch the evolution this melt season!
I'm afraid, I think you're grasping at straws.  Hudson is looking pretty thin and temperatures have been pretty high there recently.  Why do you think Quebec is exceptional when it comes to the ground insulation effect of snow cover?

Hudson is relatively thin compared to the remnant multi-year ice but it is still thicker than almost the entirety of the Arctic Ocean. I think Quebec is exceptional because it is downwind of Greenland a large portion of the year, and combined with Hudson Bay, that leaves it as the region least vulnerable to warming in an AGW scenario (IMO).

Without permafrost, there is no damage underneath, either. In fact I am fairly sure Quebec has been persistently cooler than average at most times of year (but particularly summer) for the past few years, a glaring contrast to most other polar regions.

34
Arctic sea ice / Re: The 2017 melting season
« on: April 01, 2017, 01:48:11 AM »
That snow is going to melt pretty fast this year....dont see it lasting... and record volume was very warm ground due to insulation...
i think record volume is due to increasingly open arctic ocean (i.e. record low sea ice volume directly translates into record high NHEM snowpack volume), though i agree that the warm ground insulation is going to be a factor across the permafrost areas that continue to warm/melt (mostly Siberia). this is not the case in Quebec though.

i think that we will definitely see a plunge in overall extent and may end up with record overall lows but on the flipside, the situation re: sea ice may favor extended cover vs. normal in NE Siberia and especially in Quebec. this is because as we see less ice in the Arctic and as it melts out earlier, the first-year ice in Hudson Bay is likelier to outlive the ice further to the N, which (IMO) is likely to favor persistent cold air over the relatively lower-latitude areas of SE/Central Canada.

will be very interesting to watch the evolution this melt season!

35
Arctic sea ice / Re: The 2017 melting season
« on: April 01, 2017, 12:31:09 AM »
Northern Hemisphere snow cover trend line for this year is starting to approach second lowest position:
Looks like data differs substantially; the Canadians are showing about average extent but possibly still record volume.

I think there are four key areas of anomalies at the moment; on the plus side, far NE Siberia and Quebec/the hinterlands of the Hudson are all glaringly snowy at the moment, with purples now appearing in parts of these regions.

On the flipside, the western areas of North America and Russia are dominated by reds (and in the former's case, even yellows). Eastern Siberia near Okhotsk also appears to be suffering deficits.

I would posit that this heralds a very brutal melt season for both the Pacific and Russian sides of the Arctic in general, but particularly Bering/Chuchki/Barentz/Kara.


36
Can you imagine the poor polar bear, swimming the breadth between Iceland and Greenland only to be shot upon arrival? That is beyond horrific.

37
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 29, 2017, 12:32:27 AM »
<snip>

If more of the Earth's surface is reflecting more sunlight back into space (and dissipating heat more readily at nighttime as well), I would think that actually has a *larger* impact than changes in GHGs, which alter the distribution of heat retained by the Earth, not the overall amount of heat it actually takes in. The only things that can alter the latter are A) changes in the sun's output or B) changes in the Earth's reflectance/albedo.

<Snip>
My gut feeling on this is that Albedo has been the climate change driver from 1700-ish on. GHGs are just now catching up in importance.

More show fall means more light reflected back to space and more IR radiated to space.  But there is a thread on albedo warming potential.  In that thread the comment was made that snow early has less effect than snow late does.  That is as it relates to Arctic sea ice loss.
I could see that being possible/likely.

But I would actually go back farther than 1700 in terms of GHGs/albedo impact. Not in weighing one more than the other, but in re-thinking our current knowledge of what caused the changes to the earth's climate.

I do not think it is coincidental that the Little Ice Age followed the largest period of human death in our species' history. This period followed three main events; the Mongol conquest and killing of much of Asia, the Black Death, and the discovery of the Americas with the consequent genocide of ~100 million people in that episode alone.

Combined, I think we can clearly see that depopulation was a major driver (or was likely a major driver) of the Little Ice Age. This was probably not just due to a reduction in GHG emissions; the changes to continental albedo must also have been fairly dramatic, and an ensuing uptick in forested areas (although relatively short term) would have also provided a massive carbon sink. Think of all the fields/etc that went fallow & sprouted trees after the people who had tended them for several centuries died of plague, Mongols, or smallpox. That is probably at least several percentage points of Earth's total land mass!

Traveling back further in time, the "Medieval Warm Period" followed the advances and innovations of both Rome and China, which also coincided with the population peak ~1250. And while we like to think of modern humans as some kind of exceptional race, we are anything but -- and this "exceptionalism" also applies to our preconceived notions re: GHGs and the Industrial Revolution (in that, 99.9999% of people believe that GHGs only became significant following the IR).

This is far from true. In fact, papers show that total atmospheric copper emissions from the Romans and Chinese were hugely impressive, and it would take until approximately 1850-1900 for modern emissions to equal that which was put out between 1,500-2,000 years ago! Techniques for industry were dirtier by orders of magnitude compared to today's processes, so even though they may have used less resources than we do today, their processes for extracting and refining were evidently adequate enough to rival the societies of ~1900 Europe in their total emissive capacities.

Going back even further, I suspect that while Milankovitch cycles may have been the primary climate driver pre-humans, early agriculture & late hunter-gatherer societies were equally transformative, and were the point at which humans overwhelmed the global system. The changes to planetary albedo began with the destruction of megafauna, and culminated with the advent of agriculture, both of which affected decent percentages of the planetary land surface despite very low human populations.

Somewhat of a digression, but I find the subject of pre-IR human-induced climate change extremely interesting, and when you consider the historical evidence/coincidences between the planet's climate and human society, it seems that the latter has led the former, and not vice versa.

38
have to agree with kt on this, there is nothing in the barnes paper that contradicts Ding et al.  It just shows unprecedented warmth.

these papers, however DO show that 1. Anthropogenic aerosols are the primary driver of north atlantic SST and that 2. North Atlantic SST is determined by NAO conditions, ergo, NAO variability is primarily driven by Aerosol emissions.

The Ding paper only reinforces this as his teleconnection to tropical pacific variability is ALSO well understood to be primarily driven by anthropogenic aerosols.

see:

Booth et al. (2012)
Aerosols implicated as a prime driver of twentieth-century North Atlantic climate variability
http://centaur.reading.ac.uk/30590/1/30590booth_et_al_nature_2012-accepted_draft.pdf

“Individually, volcanoes and aerosols explain 23% and 66% of the temporal multidecadal variability (10 year smoothed) of the detrended NASST (Figure S5). Combining both contributions, 76% (80% after inclusion of mineral dust aerosols) of the simulated variance is explained.”

Miettinen et al. (2011)
North Atlantic sea surface temperatures and their relation to the North Atlantic Oscillation during the last 230 years
https://www.researchgate.net/publication/227298859_North_Atlantic_sea_surface_temperatures_and_their_relation_to_the_North_Atlantic_Oscillation_during_the_last_230_years

“The aSST record and the August North Atlantic Oscillation (aNAO) index show similar multidecadal-scale variability indicating a close coupling between the oceanic and atmospheric patterns. The aSST record shows a negative correlation with the aNAO indicating cold aSST during the positive aNAO trend and vice versa. Results suggest that the wind driven variation in volume fluxes of the North Atlantic surface waters could be the major mechanism behind the observed relationship. North Atlantic sea surface temperatures and their relation to the North Atlantic Oscillation during the last 230 years.”

This is very interesting to me. One thing I have noticed since studying history is the seeming correlation between the World Wars and brutally cold winters in Europe. But perhaps it is not merely correlation, but causation?

If aerosols are the primary drivers of global atmospheric patterns then it would stand to reason that as human industrial manufacturing kicks into its highest gears (i.e., during wartime), the plumes of aerosols would drift north forcing more high-latitude "blocking" and consequently allowing much colder air to enter the continents where people actually live.

We saw this happen both during World Wars I and II, especially at the onset of WWII, when 1939-40 was the most brutal winter across much of Europe since the end of the nineteenth century.

http://www.nature.com/nature/journal/v145/n3671/abs/145376a0.html

39
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 08:39:05 PM »
Finally, not to post too many times, I have been reading into the "Karakorum anomaly". This stabilization and increase in ice mass across the Western Himalayas and Karakorum range only began in approximately 1995-2000, with a steady trend towards growth continuing since then. While data is still sparse for 2011+ I suspect that those snow maps from the Canadian ice service are indeed accurate as they corroborate the recent trends in the region.

http://adsabs.harvard.edu/abs/2015EGUGA..17.1686Z

In the face of overwhelming melt, we must look at examples like the Karakorum, which run completely contrary to past notions of what would happen, and ask: why is this occurring?

I would postulate that the impact of additional water vapor (and consequent glacial advance) manifests earlier in the highest altitudes of the Northern Hemisphere, and slowly begins advancing downward in elevation (similar to the ideas put forth by johnm23). The relatively slight warming we have seen in these regions has now seemingly reversed as snowcover has become more impressive on a year-round basis.

I suspect that over the next ten years we will see this continue across the Karakorum and Western Himalayas while also witnessing similar reversals in trendlines in areas even further down in elevation, like the peaks of the Rockies, Alps, and mountains of Southwest Asia. So far any positive anomalies have seemingly been restricted to altitudes of 5KM+, but as the other moisture feedbacks continue to accelerate (i.e., ++snowcover), they will begin to occur in many other regions as well.

It is important to note that the above does ***NOT*** discount overall global warming or anthropogenic climate change, and would also seem to directly refute the notion presented by several posters & papers in this thread that CO2 is the end-all. Of course CO2 is very important, but I believe (and the crux of my argument has been) that albedo feedbacks are even more crucial. I would compare CO2 + albedo to a match with a tub of gasoline; on its own, the gasoline is whatever, but when you add fire, boom. 

EDIT: I may have been wrong about elevation, it seems trend has been slightly positive in highest elevations but most positive in lowest elevations of the Karakorum, here is a full paper which is quite interesting on the subject:

http://sci-hub.io/10.1007/s00703-016-0440-6

40
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 08:30:37 PM »
But that's where the problem is, right? The temperatures will not lower in the foreseeable future.

My point is not that this is not happening today -- it is that the mechanism resulting in increasing fall/wintertime snowcover will soon overwhelm spring/summer snowcover as well, even if it may take another 5-10 years to kick into gear.

The mechanism, ie global warming via CO2 forcing, is going to continue to increase as well and overwhelm fall/wintertime snowcover. At some point snow will turn into rain.
Globally the temperature may not lower, but regionally, as Hansen's charts and maps show, it is already beginning to happen in certain spots and is likely to become more prominent as AMOC shutdown continues.

More importantly, as the linked study re: glaciers in Sweden shows, it seems that high-altitude regions in Sweden (and likely elsewhere) merely need 100-150% of past snowcover averages to achieve a snowpack that does indeed last for the summer, even if temperatures remain steady.

I believe that combining the imminent temperature trends projected by Hansen with the increasing moisture resulting from an ice-free Arctic shows the above to be more than plausible, and if that is the case, we can see a clear mechanism for reglaciation that does not rely on model-ology and paleoclimate simulations.

41
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 08:01:54 PM »
@bbr2314

I find your arguments pretty unconvincing. I think you severely overestimate the magnitude of this negative feedback. Why?
Apart from the fact that your claim goes against current climate science it goes against  pretty much everything we know about past climates too.

Just have a look at Shakun etal (2012) and how the transition to our current interglacial worked. Skeptical Science has a nice write up of the paper.
The main steps are as follows (quoting from there) :

1) "Earth's orbital cycles trigger the initial warming (starting approximately 19,000 years ago), which is first reflected at the highest latitudes" (see the first attached fig.)
2) "This Arctic warming melted large quantities of ice, causing fresh water to flood into the oceans."
3)" This influx of fresh water then disrupted the Atlantic meridional overturning circulation (AMOC), in turn causing a seesawing of heat between the hemispheres."
4) "The Southern Hemisphere and its oceans warmed first, starting about 18,000 years ago."
5)"The warming Southern Ocean then released CO2 into the atmosphere starting around 17,500 years ago, which in turn caused the entire planet to warm via the increased greenhouse effect."

Evidently we didn't turn back into a new Ice age - due to a year-round snow cover nor sth. else - back then (see second figure), when the CO2 concentration was at around 220 ppm.
Why on earth should we tumble into an ice age now (or get a snow cover that lasts through the summers ), when we have 400 ppm CO2 in the air?

Yes, the fresh water influx will - or already does - disrupt the AMOC (see point 3 above and Hansen) and it will give us a very rough ride to where we headed.
But this is not a year-round snow covered NH nor an Ice Age - just have a look at the Paleo-record of  Lake El’gygytgyn during the late Pliocene (for instance in Grette-Bingham etal 2013, Science)

From the abstract:
... Evidence from Lake El’gygytgyn, NE Arctic Russia, shows that 3.6-3.4 million years ago, summer temperatures were ~8°C warmer than today when pCO 2  was ~400 ppm.

See also third attachment

To sum it up: No, snow cover will not survive the summer in the years to come & no Ice Age is cometh.

I think the research you presents has some valid points but 1) I do not believe that model-simulated biomes can be verified with any sort of comprehensive accuracy, especially at a grid scale of 50KM, and 2) I think the key point you are missing in my argument (and in yours) is that at all stages of ^ post, the Earth *has* been in an ice age, and continues to exist in an ice age.

Just because the Laurentide has almost disappeared does not mean we are not in an ice age; we still have Greenland and Antarctica, which contain vast amounts of ice that would not exist if we were not still in an ice age.

I believe it has been established that at the height of the last glacial maximum, the Arctic Ocean was ice-covered; my big question is what was the Arctic Ocean's state at the *start* of the last glacial maximum? This is a question I have not been able to answer and I suspect the answer is ice-free. I also suspect that the more heat the Arctic accumulates/the longer it remains ice-free in the context of the ongoing ice age, the *more* glaciation occurs after it hits this state (i.e., the heat influx continues until the continents/ice sheets can sufficiently overwhelm the mechanism through both albedo and freshwater feedbacks).

42
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 06:12:09 AM »
RE: what it takes for snow to make it through the summer, I have found the below with regards to glaciers in Sweden.

https://lup.lub.lu.se/student-papers/search/publication/1332886

Since the mid 1970s the general retreating trend for glacier in Scandinavian have ceased and
some glaciers have even started to advance. This is due to a more maritime influence on the
climate, which means increased precipitation in winter and lower summer temperature. A more
maritime climate can be said to be favourable for glacier growth. Under such climate conditions
is it possible that new glaciers are forming? The aim of this project is to assess the climate
conditions that are needed to initiate a glacier in empty cirques in a small mountain massif, the
Rassepautasjtjåkka massif, northern Sweden. The study area is of interest since the cirques are
located just below the glaciation limit. Since there are no moraines or other signs of glaciation in
the area it is still uncertain when the cirques were formed. Using a gridbased temperature index
ablation model, that takes into account the topographic effects on melt, the melt during the
summer was calculated and the snow that remains at the end of the melt season is what can
constitute the ground to a new glacier. Weather data has been collected in the cirques every third
hour for the last eight years and this was used as input to the model. The summer mean
temperature needs to be lowered between –2 °C and –3 °C from the current climate before snow
will remain after a melt season. An increased initial snow cover of today between 100-150%
(under otherwise equal conditions) will have the same effect i. e remaining snow at the end of the
melt season. When increasing the initial snow cover with 50% and lower the summer mean
temperature by –2 °C, snow will be left in the cirques after a melt season.
The climate conditions
that are required to create a re-glaciation are not met by conditions evaluated from proxy-data
from the Holocene. Therefore it can be concluded that glacier has not existed in the
Rassepautasjtjåkka massif during the Holocene and that the origin of the cirques extends further
back than the Holocene. According to future climate scenarios that predict increased temperature
and increased precipitation glaciers will not form in the cirques in the future spanned by the
predictions.

43
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 05:35:19 AM »
...in the midst of all the doom and gloom I have found a tidbit of relatively good news: despite his death (RIP and thank you for all the wonderful contributions), the efforts of Andrew Slater continue to be available on his website, and it seems that at least the snow component continues to update. He may be gone but he will not be forgotten, and the latest charts from his website certainly speak to the prospects of glaciers in California -- in fact across almost the entirety of the west, snow-water-equivalent this year is #1 for the date!




44
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 01:43:22 AM »
Here are the Hansen maps btw in case anyone has not seen:

http://www.atmos-chem-phys.net/16/3761/2016/acp-16-3761-2016.pdf

45
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 26, 2017, 01:28:03 AM »
In my understanding of the climate system I have not ruled out yet that rapid global warming may lead to rapid global cooling. I think it will take rapid Greenland/Antarctic melt followed by a sharp increase in volcanism. Under that scenario, the albedo and aerosol changes might be enough to cause   a global winter lasting anywhere from years to decades.

But I'm talking about ridiculous amounts of melt and an equally ridiculous increase in volcanism.
That's looking a long way out, I'm thinking not of global cooling or an ice age, although the eventual distibution of ice masses may bare some resemblance, but more of a mechanism that emerges to halt a runaway greenhouse effect. That means increased evaporation from a warmer Arctic, precipitating out somewhere high enough and remote enough from any ocean to survive summer melt, and with minimal change of elevation between there and the sea, so the Altai mountains/Mongolia fit the bill in Eurasia, and southwest of Hudson going towards Montana in the Americas. I know too little about atmospherics to think properly about this, but it seems to me if you add the latent heat of evaporation to that of freezing/melting thats a way of lifting vast amounts of energy from the Arctic and dumping it far to the south high up in the[now dry] atmosphere, plus if this kicks off as a random but powerful weather event the transformation of the vapour to solid, and consequent loss of volume, could be self reinforcing. Once established, and it may take a number of false starts, it's possible that it would create it's own weather systems.
I think you have hit the nail on the head 100% re: what I am attempting to describe.

I fully acknowledge everyone's comments re: current feedbacks and the current decline in spring snowcover. That is not what I am debating, though it is undeniable that spring extent has fallen in recent years.

However, if one were looking at the data back in the 60s/70s (if we had the data then), one may  have come to the same conclusion re: fall snowcover then (irreversible decline). My point is not that this is not happening today -- it is that the mechanism resulting in increasing fall/wintertime snowcover will soon overwhelm spring/summer snowcover as well, even if it may take another 5-10 years to kick into gear.

I suspect we are already at the bottom of the trendline re: spring snowcover (again, could be wrong), and that as the situation up north continues to unravel, we will see a rapid uptick beginning. Already, this year seems to be bucking the trendline in spite of the record warmth. Perhaps we aren't +1SD in extent, but we are within range of normal, and in terms of volume, we are still *way* above normal.

RE: Neven & the comments on Ewing-Donn -- to my eyes, it still seems to be plausible? The comments afterwards seem to me to indicate that we still do not fully understand how ice ages come about, so it certainly does not seem to have been discounted as a plausibility as we head into the future (though perhaps in the past it was not a mechanism for change, that does not mean it cannot be in the future given our unprecedented situation re: GHG emissions simultaneous with an ongoing albeit seemingly waning ice age).

On its own, Ewing-Donn may be merely plausible, but I believe they ignored the impacts of freshwater melt/AMOC shutdown. Combining the theory of Ewing-Donn with the findings of Hansen et al and their anticipated cooling based on AMOC shutdown and Antarctic melt *alone*, leads me to believe that if anything, Hansen's anomalies may be underestimating the impact of the freshwater melt. When you join these two theories together, I believe we can make much better sense of ice ages. That is also not to say Milankovich cycles are unimportant -- clearly, they matter -- but we are currently in a situation where both human and natural forcings are at a seemingly unprecedented head-to-head battle that, IMO, can easily overwhelm the relatively minimal changes in solar forcings that have previously led to climactic changes (i.e., in lieu of a massive asteroid impact or supervolcano, humans are the confounding atmospheric variable).

46
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 24, 2017, 05:40:00 PM »
bbr2314, did you have a look at the Ewing-Donn theory yet, and why it was rejected ultimately?
I've read the links but I missed the part about why it was rejected, can you re-link to the specific bits? Appreciate it!

Also I think Ewing-Donn misses the component of AMOC shutdown/freshwater release from Greenland/Antarctica.

47
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 24, 2017, 03:05:26 PM »
The way I see it is that thicker snow insulates more at night/winter, producing even lower surface temperatures (particularly over land, as the sea-ice is forming later/is thinner than in earlier years). Therefore less energy is being radiated from the underlying surfaces.
But when the seasons shift the warming climate results in melt starting earlier and the "snow-off" dates are getting earlier in spite of the thicker snow. This then contributes feed-back for increasing the Arctic warming.

I have not seen thicker snow = more persistant snow. Even in the Arctic 2m ice can melt out over the summer, and that is a lot of snow equivalent.  Even at higher altitudes snow-lines are retreating up mountains and glaciers so warming is beating cooling.
So far, we have not seen snow persist through summer in any of these northern locations -- no disagreement there.

I suspect the tipping point may start gradually but begins once we see our first summer where snow *doesn't* melt at all locations that normally see this happen. This is currently very difficult, but how much more additional snow do we need in parts of Siberia and Quebec for this to be a more realistic possibility?

Additionally, one must consider the regional forcings that will soon dominate climate in these regions. While the Arctic continues to lose volume, Hudson Bay will likely remain relatively steady given its surroundings as well as the fact that it has always melted out every year.

What happens when the Arctic Ocean is mostly ice-free in June/July but Hudson Bay is not? I suspect that would encourage longer durations of colder airmasses across much of Canada (especially Quebec) through the summer. And consequently, that also increases the potential for certain regions to begin building snowcover through spring and at least the early part of summer, at least relative to the 20th century.

48
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 24, 2017, 02:58:52 PM »
If more of the Earth's surface is reflecting more sunlight back into space (and dissipating heat more readily at nighttime as well), I would think that actually has a *larger* impact than changes in GHGs, which alter the distribution of heat retained by the Earth, not the overall amount of heat it actually takes in. The only things that can alter the latter are A) changes in the sun's output or B) changes in the Earth's reflectance/albedo.

Given this, I suspect that we have vastly underestimated albedo's impact on overall global climate. Even if the amount of land that is snowcovered in a given year only increases by 10%, that is an absolutely *huge* amount of solar energy (~3% of planetary total!) that is now being deflected back into space.

If someone can provide more concrete numbers or throw my ideas into the garbage can either would be appreciated.
Climate denial garbage can, imho.

Garbage can is too small. You're gonna need a dumpster for that.
I have not denied anything, and saying ignorant things/attacking different points of view when I have clearly said *I could be very wrong and I would like evidence* over and over again is how you end up with an ignorant and uninformed perspective. I am 100% on board with AGW/climate change and the fact that you cannot consider that it could have unforeseen consequences that could be even worse than what happens in a warming world shows you are the denier, not me.

49
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 23, 2017, 09:41:19 PM »
Also: I am actually pretty sure Eastern Europe has been fairly cold/snowy this winter?

On a related note, I am wondering if a mechanism to explain the European warmth can be found in the ice-free Kara/Barentz.

These promote warm air rising into the Arctic as well as into Greenland, while simultaneously encouraging the cold Arctic/Greenland airmasses to drop south on the backside of these intrusions. This usually happens either through Quebec or to the east of Greenland.

In either case, as the airmasses plunge south they are now seemingly heading towards Spain and Morocco/Algeria, (or alternately S through Scandi. into Eastern Europe) where the former have allowed the Atlas Mountains to be very snowy relative to normal which promotes cold and snow over the rest of NRN Africa. These airmasses get "stuck" south of the very warm Mediterranean waters and travel east, with Turkey and Iran lying in the path of both Arctic Express trains, translating into the extreme cold and snow anomalies that we are now seeing in both of those regions.

That leaves much of continental Europe relatively warm as it is stuck in the "in between" of airmasses plunging to the west and to the east, with the ones coming from the west facing the natural heat barrier of the Mediterranean, which pushes them south.

Hopefully this makes some sense?? It also explains why we see the Sahara turn into a wet environment every couple thousand years, coincident with +++snowpack in the mountains of Algeria and Morocco.

50
Permafrost / Re: Negative Feedback of Positive Snowfall Anomalies
« on: March 23, 2017, 09:23:38 PM »
The air in the Arctic was dry in the past, but not anymore. There seems to be so much moisture now that it cannot be contained. I am no expert on that subject, and am sure there are others that can clarify.
Correct! But I am not talking about the Arctic re: decreasing/stable moisture, as it is definitely warming & moistening (also due to the loss of albedo); I am referencing land areas that are newly-covered by snow when they usually aren't.

in fact much less land is coverd by snow, i.e. all of nothern europe and big parts of eastern europe remain mostly snowfree or snowpoor as compared to i.e. when i was a child about 55 years ago. taking specific spots that due to warmer and wetter conditions have a bit more snow in some years is not target leading but misleading. i have observed for quite some time that you want to convince us that an ice age lays ahead. ok that's an opinion but so far of IMO (and thats also an opinion LOL) that i won't even enter a discussion. there has never been an ice age at times when i.e. CO levels were so high and still increasing, that alone tells the story but then there is much more that tells a future of warming and not one of cooling (overall, not locally) there will always be local counter effects due to air and water currents as well as shifting vertical air movement areas but the planet earth will get warmer as long as we add heat and heat containing factors. of course the process will not be linear at all times but persistent in the long run.

So...

1)

in fact much less land is coverd by snow, i.e. all of nothern europe and big parts of eastern europe remain mostly snowfree or snowpoor as compared to i.e. when i was a child about 55 years ago.

^I am speaking hemispherically re: charts/etc. Some regions see more warmth, some more cold. Europe has been warmer in general so far and not that snowy. Alas.

2)

"i have observed for quite some time that you want to convince us that an ice age lays ahead. ok that's an opinion but so far of IMO (and thats also an opinion LOL) that i won't even enter a discussion. there has never been an ice age at times when i.e. CO levels were so high and still increasing, that alone tells the story but then there is much more that tells a future of warming and not one of cooling (overall, not locally) there will always be local counter effects due to air and water currents as well as shifting vertical air movement areas but the planet earth will get warmer as long as we add heat and heat containing factors. of course the process will not be linear at all times but persistent in the long run."

I am not trying to convince anyone an Ice Age lays ahead, merely stating that we should not ignore feedbacks and the potential for negative ones is equal to positive ones despite AGW (IMO). Our dataset is extremely limited but what we *do* know is that when the Earth is in an Ice Age, it generally does not warm past a certain point without flipping back into a colder state.

Where your post is specifically wrong is where you say "there has never been an ice age at times when i.e. CO levels were so high."

We still have ice sheets covering Greenland and Antarctica which means that we actually *are* still in an Ice Age, so by default that statement is incorrect. Whether we exit the current Ice Age or plunge back into the depths of the freezer is the question facing humanity today. Given recent history of the past few million years, Younger Dryas etc argue we are more likely to pivot back to cold versus lose all the ice on Greenland/Antarctica, though you *are* correct that we have (seemingly) never had an ice age at a time when CO2 levels were so high as they are today, which means that either direction is possible.

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