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AnotherJourneybyTrain

Seeing that Global Sea Ice is still in bottom place do we call Global Sea Ice a useless statistic or expect a real surpise might be in store over the next two months?

Elisee Reclus

Perhaps someone can answer a question for me...

In polar summer, when the sun is high in the sky for many hours of the day, solar radiation is not reflected back into space and is absorbed by open water which tends to add heat energy to the sea, promoting further ice loss.

However, at the opposite pole, (or in winter) where it is dark and the sun is low or missing in the sky, open water is not insulated by ice cover and gives up its heat by evaporation and radiation.

My question is, do these effects tend to compensate for one another, balancing the heat budget in the long run, or does one take precedence? I suspect the heating due to ice loss overwhelms the cooling due to ice loss, but I really don't know this for a fact.

Can anyone shed any light on this for me?

Paul Pentony

Elisee
I'm no expert but one consideration would be that water is much more transparent to incoming short wavelength radiation than to outgoing long wavelength radiation. This means that heat loss due to radiation is restricted to a very thin layer at the surface.

Elisee Reclus

Dear Paul,

Your comment seems reasonable, but I suspect heat losses due to evaporation (even at near-freezing temperatures) probably greatly exceed those due to thermal infrared emission from the water's surface. Also, with even a modest ice cover, the sea surface is protected from the cooling effect of wind.

Although the Arctic ocean may be only a few degrees above the freezing point of salt water, Under a thick cap of ice it must represent a great reservoir of heat energy.

Likewise, a cloud cover would also have the dual effect of protecting the Arctic sea from solar radiation, while simultaneously protecting the sea from heat loss at night.

Surely there must be some mathematical expression that provides a first order summary of these effects. There are only three ways heat can be transmitted; radiation, conduction and convection.

Of course, its all a moot point, as long as the overall transparency of the atmosphere in the infrared continues to increase due to greenhouse gas forcing, any negative feedback mechanisms would eventually be overwhelmed.

Elisee Reclus

ERRATUM: what I meant to say above was:

"OPACITY of the atmosphere in the infrared continues to increase"

wayne

The current apparent slowing of sea ice extent melt is a by-product of the advent of summer 3 weeks earlier than last year:

https://eh2r.blogspot.com/2019/05/early-switchover-warming-signal-slows.html

What happens next is strictly a matter of Arctic solar penetration, which in turn depends on how much heat will widen the temperature dew point spread. If summer comes earlier, this spread has a very high chance of being large.

AnotherJourneybyTrain

http://www.usairnet.com/lc/help/?q=dps

This link might help us all keep up(!??!)

Jim Hunt

I'm not entirely sure that the cyclone "appeared out of nowhere" Wayne! The US Navy (amongst others) spotted it in advance:

http://GreatWhiteCon.info/2019/05/melt-pond-may-2019/

However I am of the opinion that the summer melt has indeed started early this year:

Currently extent is significantly below 2012, albeit somewhat above 2016 at the same time of year. And what of melt ponds? In 2012 there was evidence of less snow cover over land and more surface water on the ice on the Siberian side of the Arctic.

Other than that Arctic sea ice in 2019 looks to be in worse shape than in 2012.

AnotherJourneybyTrain

So, Jim, what is that Dolphin looking shadowy figure on worldview just shy of the pole all about?

AnotherJourneybyTrain

Global Sea Ice Area just took a dive... this has to mean something doesn't it!??!

AnotherJourneybyTrain

sark, from the forum thread: Atmospheric connections, structure, and long range weather forecasting
« Reply #13 on: May 27, 2019, 07:33:20 PM »


    Air temperatures in the Arctic. This is DJF 1000mb potential temperature. You'll get the same signal from 1000-850mb for air temperatures.

    In the cylindrical view it has the character of a standing wave. No wonder chaos reigns.


What does he mean by, "..it has the character of a standing wave?"

wayne

Yes Jim

It did come from somewhere , likely Alaska, but appeared to materialize spontaneously :)

2012 has something similar to 2019, albeit by the models which call for El-Nino to grow. 2012 had a small El-Nino which dissolved after mid July or so.
My opinion agrees with yours, 2019 is worse than 12, so far. There has been substantial wet systems , ie precipitable water seems higher now a days....

AnotherJourneybyTrain


Well, Wayne:

Is it raining in Barrow, for instance, because the precipitation moving graphic from the above link seems to be showing that ... and how is this different compared to other years because I can't tell?

wayne

Hi Another

That is the biggest highlight of 2019 to date, the incredible warming of Alaska region for months. Not for a few days, but since late last year. You'd think Alaskans would be loud about this.... There is definitely a consistent higher total precipitable water column, a warming by-product of course.

wayne

By the way Jim

I thanked you for one word correction on my web page latest article...
nisi perfectum

Jim Hunt

AJbT - What "Dolphin looking shadowy figure" would that be? Do you have a picture, or perhaps a Worldview link to illustrate what you're referring to?

Wayne - Thanks for the mention! I'm familiar with cold core and warm core cyclones in the North Atlantic. However can you elucidate further re their Arctic cousins?

Jim Hunt

Regular ASIB readers may recall that many moons ago I was "outed" and then "banned" by a certain Anthony Watts?

Here's the latest update on that tale of woe:

https://twitter.com/GreatWhiteCon/status/1133643627895382018

A tweet from my Arctic alter ego to ex Prof. Judith Curry, purveyor of porky pies to the US Congress (PPPUS for short).

AnotherJourneybyTrain

Jim, The shadowy dolphin looking figure is on the may 25 worldview pic of the Artic and at the 200km scale can be seen from about 600km in front of the Laptev Sea.(.. and is itself atleast 600km long!)

https://tinyurl.com/y4ypg2oy

[I will never watch flipper the same again: luckily Paul Hogan adds that can't-be-beat comic relief!!]

Jim Hunt

Thanks AJbT,

I see what you mean :)

I added a Terra 3-6-7 layer which made it obvious that the Arctic Dolphin is constructed of clouds.

Meanwhile my alter ego engaged Judah Cohen in conversation on Twitter yesterday:

https://twitter.com/GreatWhiteCon/status/1133776436702134272

We concluded that "great minds think alike!", and that in Judah's words:

"If polar cap geopotential height anomalies remain on the warm/positive side for much of the summer, this could result in accelerated sea ice loss relative to recent summers."

AnotherJourneybyTrain

Thanks Jim, I might try adding that layer you are talking about but because I didn't know what they did I just never bothered.

Personally, I predict a catastrophic June Cliff because

    a) Many regional seas within the Arctic-proper are down... b) the sea ice temperature map seems primed by weakness... c) the DMI Temp has a trajectory that spells nervous times ahead when combined with the previous two... d) The Global Sea Ice Trend has to mean something.

wayne

Hi Jim

Yea there could be 2 types in the sub-Arctic, but Arctic summer cyclones
give seldom surface warmer temperatures than adjoining anticyclones, for the mere reason that permafrost and sea ice double team on the extra clouds albedo factor, when cloudy the energy imbalance favors a cooling on the surface. As opposed to when there is an anticyclone with 24 hour sunlight. You have to spend a night in a tent in arctic summer to know that you need a very large cushion not to feel the cooling from below. In the upper air there can be warm cores, but the surface remains cooler.

AnotherJourneybyTrain

The Beaufort Sea looks like a swimming pool- no clouds and just looking like the sun could prove to be an ongoing problem... everything else looks cloudy extremely cloudy of course... half of todays update seems to have uploaded!

wayne

Noticed your weather being a bit regular? Lots of rain in one place, a lot of sun in other locations?


https://eh2r.blogspot.com/2019/06/stall-all-northern-hemisphere-systems.html

The Arctic climate is important, as important as ENSO...

AnotherJourneybyTrain

I find that DMI temperature hitting the 273.15K mark on this date a very very “real-world” test. I declare the next 7 days super interesting…. from a pure science pov in the very very least!

THEN, further, how influential will that “next seven days” prove to be and thus, ultimately, how significant will todays very scary data prove to be…. (because I am a little scared!)((The curve is supposed to be very very uniform at this approximate day of year for very very stable reasons, is it not!??!))

AnotherJourneybyTrain

Also, from the NSIDC June 4 update:

    As averaged for May, there was an area of high sea level pressure, an anticyclone, centered near the pole. This pattern drew warm air from the south into Baffin Bay and into the Arctic Ocean. Also, air under an anticyclone descends and warms. Both factors help to explain the unusually high temperatures over much of the Arctic Ocean.
AnotherJourneybyTrain

Also, from the NSIDC June 4 update:

    As averaged for May, there was an area of high sea level pressure, an anticyclone, centered near the pole. This pattern drew warm air from the south into Baffin Bay and into the Arctic Ocean. Also, air under an anticyclone descends and warms. Both factors help to explain the unusually high temperatures over much of the Arctic Ocean.
Sam

AJbT,

I would add to your list that there is now almost zero 4 meter thick ice left. The last sliver is just north of Greenland in an area that is being consumed from both sides. Also, as the graph Wipneus posted shows, the ice anomaly is worse than and approximating the 2012 anomaly.

If June continues as warm as it appears, a cliff seems very likely.

Sam

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