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Messages - Dharma Rupa

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101
Arctic sea ice / Re: Global sea ice area and extent data
« on: September 11, 2018, 09:42:55 PM »
The second graph within a few days where the pen is writing its line on previously untouched areas...

Yes, but with the tendency of North and South to see-saw, if it hard to say exactly what this means.

I guess we can at least say exactly that -- previously untouched.

102
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 11, 2018, 01:54:01 AM »
But cut some slack to this poor clapped out analyst and his poor clapped out laptop. Weep, sniffle, reach for handkerchief.

My poor slave driven....whatever

I will say that you might have found a way to capture WACCy.

103
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 10, 2018, 09:04:54 PM »
The graphs are a bit hard to interpret.  Is the software smart enough to put a vertical line between the averages and the last three years?
No, but maybe I am

Hehehe...You see what my problem was then.
Will the attached do? ('cos it's all you're getting)

It makes it clear that there is a difference...I guess noting the way the lines bend at the decade is a bit too pedantic.

This is fine.

104
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 10, 2018, 07:35:55 PM »
The graphs are a bit hard to interpret.  Is the software smart enough to put a vertical line between the averages and the last three years?
No, but maybe I am

Hehehe...You see what my problem was then.

105
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 10, 2018, 07:27:01 PM »
Bering Sea - now a maritime sea, (that sometimes has a bit of ice in it)
Central Arctic - still an ice desert, (that sometimes has a bit of open water in it)

The chart makes it rather clear that the CAB is less of a desert than it used to be.

106
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 10, 2018, 07:21:30 PM »
The graphs are a bit hard to interpret.  Is the software smart enough to put a vertical line between the averages and the last three years?

107
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 10, 2018, 05:25:19 PM »
PERCENTAGES OF OPEN WATER IN THE ARCTIC

I started with one figure - the calendar year. After including all the comments - too many figures

Dividing it into freezing season and thawing season told me less than I expected.  It looks like it might be losing ice slightly faster in Winter, but not enough to write home about.  Fine with me if you lose that measure.

Getting it by sea, or by Atlantic versus Pacific, seems much more important.

P.S.  Neven's division into 4 sections such that two of them are the Atlantic and Pacific sides and two are the continents might be nice.


108
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 09, 2018, 11:39:15 PM »
P.S. If we are going to talk about Atlantification then eventually we are going to have to distinguish Pacifying.  Probably should get the basic idea sorted out first.

109
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 09, 2018, 11:21:27 PM »
Thank you!  Now all I have to do is try to absorb that...

(first impression is that it is pretty much year-round, but a graph or two might help.)

110
Arctic sea ice / Re: The 2018 melting season
« on: September 09, 2018, 09:42:34 PM »
DMI 80N seems to be rather intent upon 1 degree above climatology.  I'm betting it will begin to put more average distance as we get into freezing season -- but of course, this is a bet.

111
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 09, 2018, 08:38:23 PM »

I'd rather see two (or three) numbers.  One calculated from the beginning of September to the end of March and one from the end of March to the beginning of September (and your current calculation or a variation with the year starting end of March).

(I think the Winter number would be the real Atlantification number.)
I'll add one to three to get four and suggest going by celestial days, equinoxes and solstices, you'd still get a winter number after december solstice. If you go by two please do it by equinoxes so there's a physical reason to it, there's probably more use to such an index that takes in account the available sunlight. You could also calculate it for only the period when it's dark or wholly lighted say... Above 75N?

I was thinking about going by the Sun, but there is the problem of a delay, and I can't think of any physical justification for "equinox plus 15."  You want to more or less capture the usual max and the usual min as the boundaries -- but I can't say how.


112
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: September 09, 2018, 02:44:48 PM »
The intention was not to create a measure that would replace all others as in Douglas Adams' "42" but to create a measure that gives a better idea of progress in the conversion of the Arctic Ocean from an ice desert to a maritime open water sea over the last 40 years.  The climate works on an annual basis, so a measure for the whole year is needed. I am doing a write up on my thoughts on why such a measure is needed, but decided to chuck the results into the arena to see the reaction. Already I am having a think about reactions received so far..

I'd rather see two (or three) numbers.  One calculated from the beginning of September to the end of March and one from the end of March to the beginning of September (and your current calculation or a variation with the year starting end of March).

(I think the Winter number would be the real Atlantification number.)

113
Arctic sea ice / Re: How soon could we go ice free?
« on: September 08, 2018, 02:30:54 PM »
...
I don't care to predict the end of Summer Ice, since I don't think anyone has any real handle on that, but I say that when the Summer Ice goes the Winter Ice will soon, if not immediately, follow.

The collapse of the Arctic cell and Atlantification will feed each other to end it.

P.S.  I am only talking about the CAB.  Ice near the continents might keep showing up for decades.

I cannot say that I agree.  Why would the ice in the center of the ocean make that much more difference than the ice near shore?  The ice will retreat slowly (sometimes more rapidly) towards land.  I would expect the effects of this to be roughly proportion to the amount of ice present.  Why would the loss of 80% of the ice make that much more difference than 60%?

The Arctic Cell is already in the process of collapsing.  That is what all the Jet Stream talk is about.  It is collapsing because of the reduction in sea ice.  When it collapses completely then the climate over the Arctic Ocean will be much like that over the North Atlantic, reinforcing the end of the Arctic Cell and the sea ice.

The continents are not going to warm in Winter nearly as quickly, therefore you are likely to find ice near (surrounded by) land.


114
Arctic sea ice / Re: How soon could we go ice free?
« on: September 07, 2018, 09:37:43 PM »
[Moved from the 2018 area & extent data thread]


Earlier this summer I posted four scenarios for extent loss:

https://forum.arctic-sea-ice.net/index.php/topic,2057.msg158764.html#msg158764


I think it will be some variant of scenario 4, except I wouldn't know which year.  I think "the end" will come suddenly, and I don't think anyone has a handle on when that end will happen.

Basically, I expect the Arctic Cell collapsing and the CAB becoming part of the Atlantic to happen at the same time -- I just don't know the time.
Good arguments behind that happening.  It would be a natural follow-on from a point I made earlier.  Once the enthalpy in the Arctic builds up to a sufficiently high level we could easily see major changes in heat transport that will rapidly flip the system into an entirely new state.

in this thread i agree 100%, just not in the "year round thread" ;) ;)

5 years are still pessimistic (considering we don't WANT to see a BOE any time soon) but as you say, the possibility for a sudden death of summer sea-ice cannot be entirely discarded.

I don't care to predict the end of Summer Ice, since I don't think anyone has any real handle on that, but I say that when the Summer Ice goes the Winter Ice will soon, if not immediately, follow.

The collapse of the Arctic cell and Atlantification will feed each other to end it.

P.S.  I am only talking about the CAB.  Ice near the continents might keep showing up for decades.

115
Arctic sea ice / Re: How soon could we go ice free?
« on: September 07, 2018, 08:36:02 PM »
[Moved from the 2018 area & extent data thread]


Earlier this summer I posted four scenarios for extent loss:

https://forum.arctic-sea-ice.net/index.php/topic,2057.msg158764.html#msg158764


I think it will be some variant of scenario 4, except I wouldn't know which year.  I think "the end" will come suddenly, and I don't think anyone has a handle on when that end will happen.

Basically, I expect the Arctic Cell collapsing and the CAB becoming part of the Atlantic to happen at the same time -- I just don't know the time.
Good arguments behind that happening.  It would be a natural follow-on from a point I made earlier.  Once the enthalpy in the Arctic builds up to a sufficiently high level we could easily see major changes in heat transport that will rapidly flip the system into an entirely new state.

OK.  We agree on the what, but what about the when?  I am inclined to think it will be soon, but so far I have seen nothing persuasive to argue sooner or later.  I think it will be soon simply because the Industrial Revolution started in the early 1800s; which is not a good argument for timing.  I think asking for timing from the global models is simply casting bones.

116
Arctic sea ice / Re: How soon could we go ice free?
« on: September 07, 2018, 03:05:08 PM »
[Moved from the 2018 area & extent data thread]


Earlier this summer I posted four scenarios for extent loss:

https://forum.arctic-sea-ice.net/index.php/topic,2057.msg158764.html#msg158764


I think it will be some variant of scenario 4, except I wouldn't know which year.  I think "the end" will come suddenly, and I don't think anyone has a handle on when that end will happen.

Basically, I expect the Arctic Cell collapsing and the CAB becoming part of the Atlantic to happen at the same time -- I just don't know the time.

117
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 07, 2018, 02:44:37 PM »
Absent massive intervention, the only argument right now is how soon that will take place.

I don't have much to say on when a Summer BOE will happen.  My main contention is that Winter BOE will follow Summer BOE almost immediately (Equable Climate).  I base this mostly on the geologic evidence that climate change tends to happen suddenly in steps, not slowly and continuously.

I do think the Summer BOE will be soon, but I don't have any good reason for thinking that.


118
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 07, 2018, 12:01:20 AM »
A BOE requires a sufficiently large heat budget combined with a rate of transport (into and out of the Arctic) that exceeds the ability of local conditions to maintain temperatures that overwhelm the ice.

Into and out of???   The heat has been building there since at least 1800.  The issue is transport up and down, not in and out.

119
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 06, 2018, 10:39:27 PM »
if you mean "could happen any time" together with "year round" it's a clear now, can't happen and this is physics, calculating the energy needed to melt all the ice and keep the arctic ice-free in winter is simply not there and can come from nowhere in such a short time that the terms "imminent" or "could happen any time" are valiid and quite far from it.
All the energy is right there.  It might not be within snorkeling distance, but it is within SCUBA diving distance of the ice.

120
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 05, 2018, 05:44:45 PM »
As to the year-round BOE, IMHO it will take a long time after the first September BOE, decades or centuries, even if we continue the BAU trajectory (which we probably won't due to collapse, but that's for a different thread).

Which of us is right is entirely up to the Fresh Water Lens.  If it stays there you are right.  If it drains away I am right.

The survival of civilization is probably a topic for a different Forum, not just a different Thread.


121
Arctic sea ice / Re: The 2018 melting season
« on: September 05, 2018, 05:34:39 PM »
A term can't help how people use it so preferably we just tell people their use is incorrect? With one thread per melt season a bit of education might work?
I agree. GAC has been abused here this season (though the last few days may be an exception - not my area really), but it's still a useful and meaningful term when used properly.

Having avoided using the term myself, may I suggest that it be reserved from here on to 1) a storm larger than the GAC of 2012, and 2) larger than the last GAC...That is, in order to be a GAC it has to be the largest/longest storm as of the date it happened.

122
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 05, 2018, 05:18:55 PM »

The Hudson Bay experiences a BBE every year and continues to freeze reliably in the dead of winter. Explain to me the mechanism that will prevent temperatures from plunging below the freezing temperature of sea water in the long polar night.

Don't misunderstand me. I am not saying no such mechanism exists. I am just saying I don't know what it would be.
IIRC, the Hudson Bay is fully mixed and brackish at all depths whereas the Arctic Ocean has a cold fresh layer about 100 to 300 meters thick (dunno specifically, haven't read about its oceanography in detail recently) with a relatively warm (4 to 6C ish) salty layer below that. The idea is that the warm salty layer is mixed with the fresh layer by large storms on an open sea Arctic, although I would think the cold layer is too thick for that?

https://en.wikipedia.org/wiki/Arctic_Ocean#Water_flow

Quote
In large parts of the Arctic Ocean, the top layer (about 50 m (160 ft)) is of lower salinity and lower temperature than the rest. It remains relatively stable, because the salinity effect on density is bigger than the temperature effect.

123
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 05, 2018, 03:48:10 PM »
a) year round will take a long time (intentionally don't name my idea of how long)

b) is certainly NOT IMMINENT ?

Toss out the imminent part.  I say that when you get a BOE in mid-August you'll have BOE year round.  (Not sure about it if the BOE is at the very end of what is currently the melt season.)  All you need are long fetches to roll the water.

The Hudson Bay experiences a BBE every year and continues to freeze reliably in the dead of winter. Explain to me the mechanism that will prevent temperatures from plunging below the freezing temperature of sea water in the long polar night.

Don't misunderstand me. I am not saying no such mechanism exists. I am just saying I don't know what it would be.

Actually, I'd expect the Hudson to continue to freeze over long after the Central Arctic no longer does.  I think WACCy weather will become the norm for awhile before equable climate.  So I'd also expect the peripheral seas to freeze over in Winter for a number of years after the CAB becomes a foggy sea instead of a desert -- at least the seas close to Canada and Russia.

124
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 05, 2018, 02:10:57 PM »
a) year round will take a long time (intentionally don't name my idea of how long)

b) is certainly NOT IMMINENT ?

Toss out the imminent part.  I say that when you get a BOE in mid-August you'll have BOE year round.  (Not sure about it if the BOE is at the very end of what is currently the melt season.)  All you need are long fetches to roll the water.

125
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 04, 2018, 10:14:04 PM »
the long term change in ocean chemistry. Changes in saline ratios, oxygen depletion, higher water temperatures and species migration will have much bigger negative feed backs.

It would be interesting to see more about effects of seasonally ice-free conditions a few thousand years ago, during the early-mid Holocene.  This has happened before, it would be nice to know what to expect.

Yes, and what I have read on the subject was just coarse enough that we can't really know what to expect in a 5-year timespan.

126
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 04, 2018, 06:03:27 PM »
Possibly depends whether you expect serious consequences from a BOE that was just due to natural variability?

I don't expect "serious consequences" from a BOE per se, given that we've defined a BOE as just crossing some arbitrary threshold (1 million km2 extent or 1 thousand km3 volume).  Going from 1.1 to 0.9 in either case will be small in effect, compared to the much larger change that has already happened.  In fact, I think the whole concept of "eek, a BOE!" is misplaced.  What matters is the long-term decline.  But people want excitement and drama...

I don't know about the immediate effects of a BOE, but I expect there to be very large and sudden changes when the DMI 80N in Summer is no longer pinned near 0.

Kind of guessing that a BOE will be at about the same time -- or possibly immediately following.

127
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: September 04, 2018, 01:20:36 AM »
Is there available a graph of the decadal averages for the north of 80 temperature? I'm interested in seeing how much the winter temperatures have increased.

This won't exactly answer your question, but it will provide some hints:

http://sites.uci.edu/zlabe/arctic-temperatures/

128
Arctic sea ice / Re: The 2018 melting season
« on: September 02, 2018, 10:28:20 PM »
The Lincoln Sea and thereabouts still looks a mess. This via Aqua yesterday:

Lots of interesting questions about there.  Any idea what the current temps are?  ((Any idea if they will fall below -10 anytime soon?  -- NVM))

129
Arctic sea ice / Re: The 2018 melting season
« on: September 01, 2018, 08:31:49 PM »
Blue line, Green line -- decisions...decisions.

[BTW -- in Boston the subways are known by color, and there are all of Red Line, Green Line, and Blue Line.]


130
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: September 01, 2018, 02:50:23 PM »
...
So, our two values - end of season maximum volume, and annual volume loss - are on intersecting trajectories.  I don't think ice loss is going to change radically.  However, increasing ocean heat and related knock-on positive feedbacks I think will increasingly erode the numbers we see for our annual maximum, and may have been key factors we hadn't previously understood, as until the last couple years, we've been far more focused on what happens in summer.

Seems reasonable to me.

131
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: August 31, 2018, 11:41:20 PM »
I will start expecting it imminently when the winter max volume drops under 20,000KM3.  When we hit that threshold, I think we will have a 1 in 10 chance that year of a BOE with relatively normal melt.  When the max drops below 19,000KM3, I think it will rise to a 1 in 4 chance.  At 18,000KM3 I think it will be 1 in 2.

Since I am expecting warm Winters and cold Summers I am unable to fully evaluate what you are saying here.

132
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: August 31, 2018, 09:56:26 PM »
Looking at the title of this thread...I don't know about it being imminent, however, I do think that when DMI 80N in Summer is no longer pinned at about 0 degrees then the majority of the CAB will fail to freeze over the following Winter.

I think the biggest single thing will be the failure of the halocline, but I also think it will be a plurality of the causes, not the majority.


133
Arctic sea ice / Re: The 2018 melting season
« on: August 31, 2018, 06:33:45 PM »
If you look at the ice front on the Atlantic side the lift-off North of Greenland looks a lot like a continuation of the same latitudinal line.

134
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: August 31, 2018, 02:10:10 AM »
The one consideration that you are ignoring is that per the research that I reference in Reply #5, the relatively freshwater layer immediately above the deeper warm layer of water, is unstable.  So it is not that the deeper and denser warm water will magically float up through less dense cooler water, but rather that the upper cooler/fresher lay may well some day flow laterally away (into the North Atlantic) which would then leave the warm water closer to the surface.

One thing I have wondered about is that if enough of the fresh water lens is removed first would it be possible for the rest of the fresh water to simply freeze?  Can the halocline collapse due to the onset of Winter some year?

135
Arctic sea ice / Re: Holy Sh!t: Year-Round Arctic BOE Imminent
« on: August 30, 2018, 10:20:41 PM »
I think I will wait and see.  I won't deny that BOE could happen at any time, but I do deny that anyone knows when.

136
Arctic sea ice / Re: The 2018 melting season
« on: August 30, 2018, 09:46:00 PM »
If the deep water flow from the FRAM slowed dramatically it would have catastrophically serious consequences for the AMOC.

I probably should take the question over to the buoy thread, but, do we have any data on the subject?

137
Arctic sea ice / Re: Arctic Image of the Day
« on: August 30, 2018, 09:40:59 PM »


I rather think the conversation has become about an Arctic Image of Yesterday.

138
Arctic sea ice / Re: The 2018 melting season
« on: August 28, 2018, 07:57:10 PM »
DMI 80N continues to drop rapidly.

???  I don't see how you can say anything about how DMI 80N is doing at the moment, and certainly not that it is dropping rapidly.  There is a slight indication that the Winter Cold will be somewhat delayed once again, but it is way too soon to say so.

139
Arctic sea ice / Re: The 2018 melting season
« on: August 28, 2018, 01:30:25 AM »
...and we will see how much bottom melt continues with the help of some stirring and mixing...

Um...how much the models think; which is the best we can have.  I think the local models have been doing pretty well...but I wouldn't call them definitive.  PIOMAS might have some explaining to do north of Greenland.

140
Arctic sea ice / Re: Northern Sea Route thread
« on: August 27, 2018, 11:55:44 PM »
Quote
now at 72.863807° N 149.126623° E
Quote
At 72°N, there are only 34 km per degree of longitude, so many of those decimals are superfluous. The 6th decimal place is roughly 3.4 cm vs 11 cm in the latitude direction.
That is where the ship's bridge is (more specifically, where the GPS instrument is).  The rest of the ship is elsewhere (i.e., at different decimal places).  [or so I learned from an old Coast Guard sailor]
It is to be hoped elsewhere is very close to the bridge

But does not get closer.

141
Arctic sea ice / Re: Freeform season chatter and light commentary
« on: August 26, 2018, 12:35:59 AM »
Bounce...

From the data thread...

That would be a fine analysis if you ignored the Battle of the Bulge on the Atlantic Front.

Battle of the Bulge ... I like it.

I was rather fond of the analogy, but unfortunately, I think the Nazi are going to win the war.

142
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: August 26, 2018, 12:30:33 AM »
Sorry, I shouldn't have started this in this thread, it's veering into analysis that goes better in the "melt season" thread. 

My fault, but let's take it over there.

Agreed...though it might not really fit there either...it is sort of a transition remark.

143
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: August 25, 2018, 09:26:42 PM »
JAXA ARCTIC EXTENT  4,904,571 km2(August 24, 2018)

[...snip...]

Resulting minimum from average remaining melt is  4.30 million km2.

JAXA has been staying persistently within the range of 4.2 to 4.3 million km2 for some time now. 

The "story" of this season seems to be that it's been basically a typical 2010s year, except that Hudson and Baffin Bays took longer than usual to melt out -- so in June and July we had first anomalously slow extent loss, then anomalously fast.  But then we got back on the usual track and now it's just marching along as usual.

Of course, having posted this, tomorrow will probably see either a century break or a freak uptick in extent...

That would be a fine analysis if you ignored the Battle of the Bulge on the Atlantic Front.

144
Arctic sea ice / Re: The 2018 melting season
« on: August 24, 2018, 02:06:32 AM »
My assumption was that you had to be very cold to get ice to form despite convective overturning The heat lost to the atmosphere has to be greater than the heat input by convection. Once the ice has formed, then the water that forms the ice becomes less saline, bouyant, and stays frozen, relying on conduction for heat transfer rather than convection. That means that its easier to form ice with no surface mixing (still conditions) and where the depth of convection is small (close to land)

Nice to have someone here who thinks of ice as a rock; which it is.

145
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: August 23, 2018, 09:02:22 PM »
(5) Eventually...

OK, but the whole point about global warming is that we haven't reached that point and at the moment the radiation is somewhat less (on average) than the 4th power.

For now, we have the effective radiative surface area increasing as the CO2 and H2O partial pressure rises, and the quantity of heat leaving not quite matching the quantity coming in (plus the almost negligible quantity due to fission),

146
Arctic sea ice / Re: The 2018 melting season
« on: August 23, 2018, 04:01:46 PM »

But the northernmost part of Greenland and Ellesmere Island do come closer to the -11 or so required to freeze sea water (as I understand it), although presumably no sea ice will form on land.

GFS 2 meter air temperature from 12:00 zulu today:

-11 ?   I think that is way off. Around-2 is about right.

I think you two are talking about two different things, though I don't know if either one of you is exactly right.  One is talking about air temperature and the other about water temperature.

147
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: August 23, 2018, 03:53:07 PM »
"NVM -- I gather that the planet is going to attempt to get rid of heat faster as it gets warmer, all other things being equal (which they aren't)."

Theory says so, and a solid dry planet would probably cool down pretty fast. On Earth, in practise this leads to more water vapor getting higher up in the atmosphere thus keeping the temperatures higher on the surface. Taking atmosphere in account, earth radiates more when hotter, we just don't notice it easily here on the ground. Please check this also from elsewhere, it's been a while when I last had to write this down, and may have mixed up some words.

That's pretty much what I was thinking, that the net result would be somewhat less than the 4th power.

148
Arctic sea ice / Re: The 2018 melting season
« on: August 23, 2018, 02:53:45 PM »
Still a bit early to tell, but it sure looks to me like the red line is trying hard to follow the blue line instead of the green line.

149
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: August 23, 2018, 01:30:42 AM »
You could also take the view that heat out varies with 4th power of temperature and this is a strong negative feedback that dominates the system and tends to prevent run away situations.

Please explain.  I'd say justify too, but I think an explanation would cover that.

(This could explain why we are not Pluto or Venus, but I don't understand it.)

The Stefan-Boltzmann law for black body radiation says that the amount of energy radiated from a black body varies with the 4th power of the surface temperature of the body. If you want to go full Venus, you'll need to add energy at a rate strong enough to dominate this effect, see: https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_law

Edit: Thank you Ned for correcting my error.

Ok....so the hotter the body is the more-more it radiates...How "Grey" is the Earth?

NVM -- I gather that the planet is going to attempt to get rid of heat faster as it gets warmer, all other things being equal (which they aren't).


150
Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: August 23, 2018, 12:35:08 AM »
You could also take the view that heat out varies with 4th power of temperature and this is a strong negative feedback that dominates the system and tends to prevent run away situations.

Please explain.  I'd say justify too, but I think an explanation would cover that.

(This could explain why we are not Pluto or Venus, but I don't understand it.)

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