"Smart" and "Stupid" Questions - Feel Free To Ask

[nanning]

Diving through the halocline

"We're sorry, but this video is not available in your region due to rights restrictions." 

[pleun]

just seach for it on youtube

[Killian]

ASKING FOR A FRIEND


Why did CO2 go up during the interglacials over the last 800,000 years?

In previous warm periods, it was not a CO₂ spike that kickstarted the warming, but small and predictable wobbles in Earth’s rotation and orbit around the Sun.

Actually, about 2.7M years. The 800k thing is related to ice cores, not how long the Ice Age has been. Properly, the entire period of glacial (what most call ice ages)/interglacial (what most think of as warm periods) cycles during which the poles have had permanent ice is the Ice Age.

FYI pedantism.

Also, CO2/CH4 spikes have been associated with some/all of the mass extinctions, even the dinosaurs, all prior to the Ice Age. Except the current one, of course.

[Istari]

What is the reason that ice, that still linger in Hudson Bay, my intuition tells me, that it should he have melted out by now, which it clearly hasn’t ...

Is this due to lack of mixing/heat transfer, or are we looking at the last of thicker ice, from rindging or som other ice thickening process ?

[oren]

What is the reason that ice, that still linger in Hudson Bay, my intuition tells me, that it should he have melted out by now, which it clearly hasn’t ...

Is this due to lack of mixing/heat transfer, or are we looking at the last of thicker ice, from rindging or som other ice thickening process ?

Are you sure it's there? (I can't look at Worldview at the moment).
If it is, then surely it's the remains of extremely thick ice from ridging. There's enough heat there to melt normal first year ice.

[JayW]

What is the reason that ice, that still linger in Hudson Bay, my intuition tells me, that it should he have melted out by now, which it clearly hasn’t ...

Is this due to lack of mixing/heat transfer, or are we looking at the last of thicker ice, from rindging or som other ice thickening process ?

Are you sure it's there? (I can't look at Worldview at the moment).
If it is, then surely it's the remains of extremely thick ice from ridging. There's enough heat there to melt normal first year ice.

GOES16 saw it there on the 3rd.

http://rammb-slider.cira.colostate.edu/?sat=goes-16&z=5&im=18&ts=2&st=20190803135051&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=20190803191051&slider=-1&hide_controls=1&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=full_disk&p%5B0%5D=natural_color&x=9539&y=919

Click to run

[wili]

Isn't the Hudson much fresher, less salty water than the oceans?

[gerontocrat]

Isn't the Hudson much fresher, less salty water than the oceans?

Yes, especially in the south.
And it is a good illustration of the WACC thing - all those temp maps last winter showing warmth in the NE and NW fringes of North America and really cold in the middle.

It is also a sea that seems to ignore AGW.

This year melt actually happened a bit earlier than average after mid-July.

[uniquorn]

I would like to show buoy data on, for example, an amsr2 map. How do I convert lat/long, which I have, to the correct stereoorthographic projection coords?

[be cause]

a bit further south .. can anyone tell me why ECMWF 850hpa has a -12'C anomaly over the Himalayas ? This seems to be a routine feature this time of year and does not compare with other forecasters . b.c.

[ReverendMilkbone]

What is the most accurate sea ice thickness chart?  A lot of people here seem to deride DMI and Polar Portal.

Also, what is the source for the "Navy" sea ice thickness chart?

[Siberian Methane Monster]

What's with the "Stupid Questions" to post and set up a user account?

What is the storm of August 2012 with 3 letters? NONE from NOAA's list.
https://www.ncdc.noaa.gov/sotc/tropical-cyclones/201208

What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO

Is this a "club" that screens out users by using ridiculous questions to keep other out?

[Neven]

Spambots are a serious problem for me. Every once in a while they figure out the answers to the security questions, and then there are daily waves of new registrations that I then have to delete by hand.

Of course, the questions have to be somewhat non-obvious to have an effect. If they are too simple, they are useless to keep out spambots. If anyone has a better method that is less time-consuming I'm all ears.

What is the storm of August 2012 with 3 letters? NONE from NOAA's list.
https://www.ncdc.noaa.gov/sotc/tropical-cyclones/201208

GAC (Great Arctic Cyclone).

What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO

AGW (Anthropogenic Global Warming).

[uniquorn]

And sure, whenever large mass of air leaves Arctic - similarly large amount must enter Arctic elsewhere. Can't be vacuum left behind, eh.

Atmosphere is 3 dimensional though and currently out of my scope but maybe some of the 500mB enthusiasts could explain what is happening today rather than 10days out.
For example, is today's cyclone centred roughly over the pole dragging warm air from much higher up that gets warmer as it comes down to sea level?
edit in italics

[HapHazard]

~~What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO]What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO~~

AGW (Anthropogenic Global Warming).

I got in with WHD, honestly.

(Wife's Hair Dryer)

[Shared Humanity]

Spambots are a serious problem for me. Every once in a while they figure out the answers to the security questions, and then there are daily waves of new registrations that I then have to delete by hand.

Of course, the questions have to be somewhat non-obvious to have an effect. If they are too simple, they are useless to keep out spambots. If anyone has a better method that is less time-consuming I'm all ears.

What is the storm of August 2012 with 3 letters? NONE from NOAA's list.
https://www.ncdc.noaa.gov/sotc/tropical-cyclones/201208

GAC (Great Arctic Cyclone).

What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO

AGW (Anthropogenic Global Warming).

Just want you to know I appreciate everything you do.

[petm]

Spambots are a serious problem for me.

Just want you to know I appreciate everything you do.

Ditto, big time.

[Pmt111500]

~~What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO]What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO~~

AGW (Anthropogenic Global Warming).

I got in with WHD, honestly.

(Wife's Hair Dryer)

Back when I got in it was IMF for their role in funding fossil use, I'm so old.

[Sebastian Jones]

~~What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO]What causes Arctic Ice Loss with 3 letters? The Sun? No! Any other answer? Ice Albedo Effect? IAE NO~~

AGW (Anthropogenic Global Warming).

I got in with WHD, honestly.

(Wife's Hair Dryer)

Back when I got in it was IMF for their role in funding fossil use, I'm so old.

Huh. I'm so old there were no security questions. Were those the good old days, or am I so old that I've forgotten that there were questions?

[HapHazard]

If you didn't answer via carrier pigeon, you're not old.

(sorry, i'll shut up now!)

[AmbiValent]

ASKING FOR A FRIEND


Why did CO2 go up during the interglacials over the last 800,000 years?

The release of stored CO2 can be both a cause and an effect of global warming.

As for the interglacials, they were started by the Milankovic cycles. Regularly, the changes in Earth's orbit and axial tilt lead to conditions in which high latitudes in the Northern Hermisphere - where there are continents that warm quicker than oceans - get a maximum amount of energy which starts a strong melting.

This melting then starts to set free stored CO2 (and also adds more water vapor to the atmosphere, which is also a greenhouse gas), which makes the melting stronger.

This melting lasts for thousands of years. During this time, the phase of optimal conditions in the Milankovich cycles has already ceased, and the process is no longer driven by them.

Eventually, the warming stops due to a new equilibrium. And since the conditions are no longer the optimal ones, a very slow cooling begins during which CO2 is stored away again. But this storing away takes a much longer time than setting it free. So after the melting at the start of the interglacial, we've had thousands of years of extremely slow cooling, and it was so slow that human civilisations developed their agriculture in this relative stability.

So the greenhouse effect of CO2 did not start the interglacial, but it kept it going long after optimal conditions has passed.

[nanning]

Great explanation AmbiValent, thank you.

[binntho]

ASKING FOR A FRIEND


Why did CO2 go up during the interglacials over the last 800,000 years?

The release of stored CO2 can be both a cause and an effect of global warming.

As for the interglacials, they were started by the Milankovic cycles.
<snip>

Milankovich can't be held to blame on his own. The length of the glacials, and the very sudden warming at the start of interglacials, cannot be explained by Milankovitch alone.

A theory first put forward in this paper by Ralph Ellis and Michael Palmer and which sounds eminently reasonable to me, suggests that as CO2 was slowly sequestered and H2O increasingly bound up in the large ice-sheets, dry conditions started to take over with large scale desertification.

A near-tipping point would be reached when desertification had caused enough dust-driven fall in Albedo over the icesheets, and the next positive Northern-hemisphere Milankovitch insolation max kicked in and, in effect, kicked the system into a very rapid warming phase.

[uniquorn]

And sure, whenever large mass of air leaves Arctic - similarly large amount must enter Arctic elsewhere. Can't be vacuum left behind, eh.

Atmosphere is 3 dimensional though and currently out of my scope but maybe some of the 500mB enthusiasts could explain what is happening today rather than 10days out.
For example, is today's cyclone centred roughly over the pole dragging warm air from much higher up that gets warmer as it comes down to sea level?
edit in italics

I would like to show buoy data on, for example, an amsr2 map. How do I convert lat/long, which I have, to the correct stereoorthographic projection coords?

are my questions too Stupid?

[cognitivebias2]

There is a canned R function here:

https://rdrr.io/github/clauswilke/dviz.supp/man/orthproj.html


orthproj: Project lat/long to x-y in orthographic projection.
In clauswilke/dviz.supp: Supporting materials for Claus Wilke's data visualization book


Edit:  actually I did not look at it that long... I'm not certain what it's coded in, but looks like Claus Wilke has a book that covers the topic:

https://www.amazon.com/gp/product/1492031089

[uniquorn]

thanks, looks like I have to get my head round R or Python so far.

[slow wing]

Uniquorn, the formulae for orthographic projection are here:
https://en.wikipedia.org/wiki/Orthographic_projection_in_cartography

They are taken from a book for which the .pdf file is available online: https://ia802909.us.archive.org/34/items/Snyder1987MapProjectionsAWorkingManual/Snyder%201994%20Map_Projections_a_Working_Manual.pdf

They are actually simple though, and simplify still further when centred on the North Pole.
phi_0 = 90 degrees
lambda_0 = -45 degrees (example with 'Greenland down')

x = R cos(phi)sin(lambda+45)
y = -R cos(phi)cos(lambda+45)

R ~ size scale of your map. You will presumably have to calibrate it using known coordinates, e.g. Svalbard.

[nanning]

I assume it's OK to put my question here.

For the pleistocene era it is said that everwhere humans came, the megafauna disappeared.
Are African elephants megafauna? I think they qualify.

[binntho]

I assume it's OK to put my question here.

For the pleistocene era it is said that everwhere humans came, the megafauna disappeared.
Are African elephants megafauna? I think they qualify.

Good question and not at all stupid! Megafauna did not disappear everywhere (for a given definition of mega ... I'll go with a brown bear or a deer being mega), but those that did survive may be categorised like this:

Wood-living megafauna survived since humans are pretty bad at hunting in woods.

Megafauna that evolved alongside humans tended to survive, in those places where they co-evolved (so elephants in Africa, but not in Europe).

[binntho]

The megafauna that wasn't hunted out of existence pretty quickly, disappeared by being pushed out by agriculture. Thus the European lion may have existed up to historical times, as did certainly the Levantine lion. The Norht-African elephant may well have lived to be captured by Romans, and Hannibal may have got his elephants from modern Morocco.

[El Cid]

I have always wondered why (if we came from Africa, so we spent more time there) the African megafauna was not annihilated while the European/Asia was.

[binntho]

I have always wondered why (if we came from Africa, so we spent more time there) the African megafauna was not annihilated while the European/Asia was.

Well it's all about adaption innit? The African megafauna adapted to us as we adapted to them. Megafauna in the Americas and Australia had no change. Once Homo Sapiens and his cousins found out how to survive in the northern tundra, the mastodont and other forgotten species such as the giant elk, the sable tiger, the furry rhinoceros etc. etc. had no chance.

[wili]

"had no change" seems like an odd euphemism for 'went extinct.'

But yeah, basically. There's a book on the topic: "Why Big Fierce Animals Are Rare: An Ecologist's Perspective"

https://www.amazon.com/Why-Big-Fierce-Animals-Rare/dp/0691023646

Of course, it's hard to know how much of a role changing climate played in those extinctions.

[Tom_Mazanec]

The climate changed wildly throughout the Pleistocene and they did fine. Then H sap. arrives and they immediately vanish.

[binntho]

"had no change" seems like an odd euphemism for 'went extinct.'

Should have ben "had no chance" - corrected now.

[El Cid]

The climate changed wildly throughout the Pleistocene and they did fine.

NOPE

[nanning]

Thank you for engaging.

So African elephants likely belong to megafauna.
Then the conclusion must be that African humans didn't hunt large mammals to extinction (apart from a changing climate, which it has done in all glacials).

They also didn't need clothes (technology) and were not in a harsh climate. Correlation?
They did not have great conquerors and so called civilisation. Correlation?

[Tom_Mazanec]

The climate changed wildly throughout the Pleistocene and they did fine.

NOPE

El Cid:
There were about two dozen ice age cycles in the Pleistocene similar in speed and amplitude. When humans reached Australia there was an extinction event. When they reached the Western Hemisphere there was an extinction event. But in Africa where they had the most time to adapt to our hunting they did relatively well, and somewhat so in Eurasia.

[be cause]

why o why do threads not show in the search . I thought weird weather was in consequences .. it wasn't .. I typed in weird weather .. not there either .. b.c.

[kassy]

But it is?

https://forum.arctic-sea-ice.net/index.php/topic,323.0.html

[be cause]

missed it at the bottom of the page .. I thought the world was over-run with weird weather .. seems everything must be normal .. b.c.

[crandles]

Do advanced search and click search 'Search in topic subjects only' and there is only 1 thread/topic with 'weird weather'

[uniquorn]

Uniquorn, the formulae for orthographic projection are here:
https://en.wikipedia.org/wiki/Orthographic_projection_in_cartography

thanks. I don't know why I failed to find that.

[Shared Humanity]

Thank you for engaging.

So African elephants likely belong to megafauna.
Then the conclusion must be that African humans didn't hunt large mammals to extinction (apart from a changing climate, which it has done in all glacials).

They also didn't need clothes (technology) and were not in a harsh climate. Correlation?
They did not have great conquerors and so called civilisation. Correlation?

The Khoisan, a hunter gatherer people in southwestern Africa (speaking the only known language which includes clicks) would hit giraffe with poison darts and then chase them for days until the poison took effect and the animal dropped. The best hunters were fast with great stamina.

It is not that game was not hunted. It is that the game evolved at the same time as modern humans so the animals had developed a healthy respect for the pesky little primates.

[Tor Bejnar]

...
For the pleistocene era it is said that everwhere humans came, the megafauna disappeared.
Are African elephants megafauna? I think they qualify.

Of course, humans didn't "come" to Africa then! 

[petm]

H. sapiens, king of invasive species.

[Archimid]

You should not hate humans. You should pity them. They are beings like all others, and they are destroying themselves. They don't even know it.

[Bruce Steele]

Shared Humanity,
"It is not that game was not hunted. It is that the game evolved at the same time as modern humans so the animals had developed a healthy respect for the pesky little primates."
 I was hiking with a couple young children today in parks with mountain lion warning signs because we have lots of mountain lions and occasionally a child is attacked. Children should never be the last hiker,an adult needs to be the last in line. Mountain lions are tracked and killed when they attack but otherwise there is no "sport" hunting allowed . Fifty years ago there were trackers with dog teams that hunted mountain lions for a bounty. They were paid to shoot them . i think wolves, cougar, bear and even coyote were hunted with a bounty because people actively try to eliminate other predators. We don't like the competition . I have a feeling the practice is very old and deep seated.

 

[Tom_Mazanec]

Of course, that is just what any sapient technophilic species is gonna do. If mongooses had developed tools they would be doing the same thing. Maybe the dolphin plan is the only way to have high intelligence in a healthy ecosystem.

[binntho]

<snip>
i think wolves, cougar, bear and even coyote were hunted with a bounty because people actively try to eliminate other predators. We don't like the competition . I have a feeling the practice is very old and deep seated.

This was common practice, predators big enough to take lambs or calves are in direct competition with farmerrs.

Fox hunting and rabbit hunting (popular sports in Europe) have a similar economic reasoning. Rabbits can destroy a field and foxes are famous for breaking into chicken coops.