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Messages - longwalks1

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1
Consequences / Re: COVID-19
« on: October 27, 2020, 10:43:44 PM »
Herd immunity is not evil, and implying that YOU should be spared from the virus as society carries on in your absence as it HAS TO FOR YOU TO SURVIVE is incredibly ELITEST and shows a disconnect from fellow humanity.

When I walked to Midtown in May, pedestrians were almost exclusively people of color who were ensuring the city carried on and continued functioning so people like those still cloistered inside could continue to do so.

Thought this might be in response to my comment where I called herd immunity evil so I will respond.

I am a white male, 64 years old, and go to work every day in one of the poorest communites in Chicago, comprised entirely of persons of color. (30% Hispanic, 70% black) I work for a not for profit that is working with community groups to bring development to a community that has suffered from decades of disinvestment. I've installed gardens, boarded up vacant buildings, connected small businesses to available resources, contributed to the revival of a rich tradition in art, routinely connect with the homeless along the commercial district and direct them to emergency services. As a white man, I have lived a life of privilege, the kind of privilege that all white men benefit from in the U.S. I decided to use the last 15 years of my professional life giving back to the city that I love.

And herd immunity which you are suggesting is the best approach will hurt the most those for whom you profess such concern, communities of color.

2
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 21, 2020, 06:39:45 PM »
After the storm of this mid October I was also wondering myself what are the consequences of the open water on synoptic forcings for ascent. As a remainder, vertical velocity are stronger for a same forcing with lower static stability. I don't know if there is studies about this subject, or if it is a significant effect, but it is an open question for me. This is probably linked to the displacement of the eddy driven jet, but I am not aware of any study really looking specifically at the consequences of this reduced static stability. This is also leading to higher wind speed at surface, as seen with the last storm. On top of that, strong inversion over ice pack, and now over the continent, is on juxtaposition of this low static stability, leading to increased baroclinic instability. But what is the magnitude of this effect ? I am really clueless. To illustrate, I have compute a crude static stability parameter, by subtracting potential temperature at 700 hPa and at 950 hPa, normalized by the thickness 700 - 950 hPa. All of this multiplied by 10 to better seen what is going on. Below 0, the atmosphere is superadiabatic, and everything above is subadiabatic. Over mountains (like, said, the Rockies...), results are of course useless, as the model interpolate trough the terrain. Maps are for, in order, the 21st to the 24th at 00Z. Didn't try to average trough time, the computer would probably have hoist the white flag before the end... We can see a persistent area of low stability over the Siberian seas.

3
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 16, 2020, 09:51:49 PM »
  leads to displacement of the polar vortex in the fall and winter months towards the Atlantic ocean. Moreover, the vortex is weakened by the warming subpolar seas on the Atlantic side. So we have a very complex problem with multiple coupled processes when we deal with increasing release of oceanic heat from the Arctic ocean in the fall and winter months.
Totaly agree
This is what is happening right now
Watch the jet stream outgrowth over Western Europe and the North East Atlantic
It's been several weeks since this has been happening without interruption, and the cold weather that it generated in France has drawn attention, we went from summer to winter without transition (in france we are living the coldest autumn period since 1974)!
We can see also how disorganized and low is the polar vortex in this moment on the Atlantic ans European side

4
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 13, 2020, 11:31:10 PM »
It's time to go to night vision using worldview terra modis viirs brightness temperature band 15 (night or day) https://go.nasa.gov/2FpoLVd
Today's image showing the effect of wind driven drift on the Atlantic front (awi amsr2 v103 from yesterday inset)

Quote
The VIIRS Brightness Temperature, Band I5 Night layer is the brightness temperature, measured in Kelvin (K), calculated from the top-of-the-atmosphere radiances. It does not provide an accurate temperature of either clouds nor the land surface, but it does show relative temperature differences which can be used to distinguish features both in clouds and over clear land. It can be used to distinguish land, sea ice, and open water over the polar regions during winter (in cloudless areas).

The VIIRS Brightness Temperature layer is calculated from VIIRS Calibrated Radiances (VNP02) and is available from the joint NASA/NOAA Suomi National Polar orbiting Partnership (Suomi NPP) satellite. The sensor resolution is 375m, the imagery resolution is 250m, and the temporal resolution is daily.

Only one Polarview S1B of the area today.

It's also worth looking at relatively cloud free sea ice north of the CAA today. High winds are forecast for this area too over the next couple of days.      https://go.nasa.gov/3dAMzSN

5
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 10, 2020, 03:12:19 AM »
FWIW, the "open water heading into the arctic night = GOOD" argument has always struck me as a violation of Occam's Razor: Less ice, more open water, later and later into the fall just does not seem "good" to me.
It’s not that it is good. It is that there are physical reasons (Stefan-Boltzmann Law) to expect that the more energy you make available now, the more energy will radiate out to space during the NH night.

The net effect is energy loss and therefore another factor to moderate, rather than precipitate, the decline of sea ice in the years to come.

A-Team is conflating this negative feedback effect that he, as scientist, knows well, with other atmospheric effects which are less clear and of more conjectural nature, to produce an overtly alarming picture.
I'll disagree mildly with the last and bolded, and to a lesser degree with how you characterize A-Team's method.

I really can't remember in 7 years where he's seriously overstated an effect or mechanism.

Or even modestly for that matter.

Frankly, I think it is hard to understate the likely impact of warming of the Laptev, ESS, Barents and Kara in particular that took place during the melting season.

I think it's hard to understate the impact of the breakdown of stratification in the peripheral seas on the Atlantic side, along with the enormous influx of heat that's being pulled along by "Atlantification".

Other posters have correctly pointed out that outgoing black body radiation will not be able to dump the heat that's been accumulated, and is *still* being imported by southerlies pulling storms, heat and moisture into the basin from further south.

I think it bears serious watching, as my "hunch" at this point is we will see an extremely anemic refreeze, with a significant reduction in end of refreeze volume, even if those peripheral seas appear to refreeze robustly.  I think the portents for next year are very serious indeed.

Edit:  What we need, desperately, this winter:

- A strong polar vortex
- Crystal clear skies
- Minimal snow on the pack

I'm pessimistic about the probability of any of them.

6
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 06, 2020, 12:41:40 PM »
To illustrate, a set of graph for the period August - Septemeber. Record for Gmo Im. E. K. Federova, breaking its record by 2.2°C (cap Tcheliouskine),or 3.5 sigma above the most recent 30 years mean... And there is ~ 1500 km between Heiss (Polargmo or wmo 20046) and Hatanga (20891), which squared is ~ 2 millions km²

7
Arctic sea ice / Re: The 2020/2021 freezing season
« on: September 26, 2020, 05:27:20 PM »
Trend in the maximum extent minus the minimum extent.
Inset map of the 2020 max and min extent too.

8
Arctic sea ice / Re: The 2019 melting season
« on: September 17, 2019, 09:28:59 PM »
One can see clearly on the Worldview that the new ice is forming on the nothern Greenland fjords and in the Nares strait. Some real (bottom) melting occur only in the Beaufort and Greenland seas. But in general the melting season is over and only compaction can decrease extent

10
Arctic sea ice / Re: The 2019 melting season
« on: August 31, 2019, 08:10:18 PM »
Losses will pick up a lot for this Time of year the next 10 days

11
Consequences / Re: Wildfires
« on: November 10, 2018, 04:24:42 PM »
I hardly know what to say about such horror and tragedy.

12
Permafrost / Re: Arctic Methane Release
« on: November 13, 2017, 02:14:58 PM »

ps:- Even if emissions are slow enough to allow decomposition in the water column, my understanding is this will be through aerobic decomposition by bacteria producing CO2 (acidification) and oxygen depletion possibly on a sufficient scale to result in wide-scale dead zones in the ocean and destruction of marine life. Any evidence anywhere?

That's basically what happens when productivity in an area is suddenly increased: increased draw-down of carbon, followed by benthic oxygen depletion. Added to that is a slow-down in thermohaline circulation due to the global temperature rise, which just makes any potential worse, and this is why the warmest periods of the Phanerozoic (e.g. Middle Ordovician and Cretaceous) are characterised by a lot of black mudstones with no benthic fossils.

My PhD was on the effects of volcanic ash-fall on Ordovician ecosystems, where the nutrient supply was from upwelling due to hyperpicnal surface waters laden with fine ash, which promptly sank on mass. (The same thing was seen after Pinatubo - a Steve Sparks paper, iirc). The result there was a mass bloom of plankton, followed by benthos, followed by a swift return to anoxia, and, as it happens, lots of exceptional fossil preservation through rapid replacement by pyrite (iron sulphide). And this was only dealing with a local scale, with lateral mixing ameliorating the effects significantly. This process is one of many reasons why CO2 capture by ocean fertilisation was such a spectacularly catastrophic idea; luckily the fish-farming element failed, so it seems to have been largely dropped.

Apologies for lack of reference - I'm currently in a small town in southern China, on fieldwork, and a long way from the literature I was using at the time!

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