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Consequences / Re: COVID-19
« Last post by Tom_Mazanec on Today at 12:26:35 PM »
The halting of mink farming in Denmark and soon the Netherlands should be worldwide, otherwise the risk of SARS-CoV-3 soon doesn’t sound far-fetched to me.
It's not just Neovison vison that is the problem, gandul. Other species live with humans in inhumane conditions, either in farms or in encrouched wilderness, and this virus infects a lot of mammals.
Arctic sea ice / Re: 365 day average extent poll
« Last post by gerontocrat on Today at 12:23:04 PM »
2019 underperforms for the next 10 days, so it will be tough.

JAXA Arctic sea ice extent data

,,,,but happened, and is likely to continue happening - see Oren's post

I attach latest table and graphs.
- 2020 extent now only 147k less than 2019,
-10k to go for a new record low 365 day trailing average, which  at the current rate of daily reduction happens on the 20th of December.....but could easily be delayed indefinitely.
The rest / Re: Good music
« Last post by Tom_Mazanec on Today at 12:20:15 PM »

Let's Hang On - Frankie Valli and the Four Seasons
The rest / Re: Good music
« Last post by Tom_Mazanec on Today at 12:16:39 PM »

Things I should Have Said - The Grass Roots
Arctic sea ice / Re: 2020 Sea ice area and extent data
« Last post by gerontocrat on Today at 12:11:04 PM »
JAXA ARCTIC SEA ICE EXTENT:  9,552,720 KM2 as at 24-Nov-2020

- Extent gain on this day 56k, 32 k less than the average gain on this day (of the last 10 years) of 88k,
- Extent gain from minimum on this date is 5,998 k, which is 445 k, 8% more than the 10 year average of 5,553 k.

- Extent is at position #2 in the satellite record

- Extent is  147 k LESS than 2019,
- Extent is  595 k MORE than 2016,
- Extent is  336 k LESS than 2012
- Extent is  476 k LESS than 2007
- Extent is  344 k LESS than the 2010's Average
On average 56.2% of extent gains  from minimum to maximum done, and 107 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 13.88 million km2, 0.00 million km2 below the March 2017 record low maximum of 13.88 million km2.
N.B. Click on image to enlarge
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« Last post by Hefaistos on Today at 11:53:52 AM »
The models quoted apply a uniform and instantaneous increase of ocean temperatures by 2 K in order to trigger MICI events, and this is one of the factors needed to initiate MICI events.

You give it 10 to 20 year to reach your "2030 to 2040 timeframe" until MICI events are initiated.
ASLR, how long time might it take in reality to get a uniform increase in ocean temperatures of 2 K?

(currently, SST's are warming with 0.07 K per decade, and deeper ocean layers warm at considerably lower rates.)

While I am too busy to make a detailed response, I note the following:

1.  I believe that their model assumes the ASE ice shelves to be in a more robust condition than they actually are today.  Thus, I believe that it will take less oceanic heat input on the underside of these currently fragile ice shelves to get them to collapse circa 2030 to 2040.

2. How much the entire ocean warms-up is not relevant to this topic, as what matters is the temperature of the modified CDW reaching the undersides of the ASE ice shelves as shown in the first attached image; which, is a function of upwelling of the CDW.

3. As shown in the second attached image, the amount of upwelling of CDW is projected to increase with time.

4. The third image shows how the influx of warm water into the ASE changes with the ENSO phases; which rapidly impacts the buttresses offered by the associated ice shelves to the ice flux out of the marine glaciers in the ASE.

I may present more information when I have more time.

You didn't reply to my question regarding the necessary temperature increase in the Antarctic seas to initiate MICI events.
Circumpolar deep water is between 1–2 °C of temperature. If we apply Pollard/DeConto's assumed increase with 2 K, it means at least a doubling of the CDW temperature. I'm just curious as to the needed timeframe for such an enormous increase of CDW temperature.
Policy and solutions / Re: Tesla glory/failure
« Last post by NeilT on Today at 10:20:27 AM »
The Tesla solution is a software/hardware solution which are two halves of a coin.  That being said, Tesla had to do a complete re-write in order for FSD to come to beta.  They are also in the process of building a true "supercomputer" to label and train the AI.  The software for DoJo is entirely separate form the software of the in vehicle AI.

Just stealing someone's software at a point in time prior to the re-write means you inherit all the problems the re-write had to solve and have none of the knowledge and skills which forced and delivered the re-write.

Also the AP software stolen works on a computer nearly 30 times slower than HW3.  FSD cannot possibly run on that hardware.

If you are going to steal a solution, it is best to steal the release candidate.  Not the pre alpha (which is what AP is in comparison with FSD).

Also it's worth working out that you might need the very fastest computer delivered by Nvidia to run it.  That silicon, right now, consumes 500w to run and has cooling issues in a vehicle.  Nvidia has a release schedule for newer silicone which draws less power, but Tesla beat them to it by a wide margin.

Most people don't really understand just how far ahead Tesla is on many fronts.  As their competitors turn to other means to compete with them, that lead will become far more apparent.  Xpeng is, I would assume, only an early instance of this  phenomena.
Policy and solutions / Re: Electric cars
« Last post by NeilT on Today at 10:04:02 AM »
If you adjust your life and driving to the prius so you don't kick in the motor, then it can work really well for you.

The report I posted showed that with these bigger vehicles, it will be much harder to avoid emitting.  It was quite correct, dieselgate all over again.  Where the stated emissions profile of the vehicle only works in one very small category and the manufacturer knows very well that this category will not be the normal use case.

If we build and tax for the very best possible use case, then the average use case will mean we did relatively nothing to reduce emissions.

The only possible way to force these PHEV vehicles into low emissions is to raise fuel prices to the point where the owners are forced into using the batteries only for most use.

That cannot happen until at least 3/4 of the country based fleet of vehicles has transitioned to some form of EV.  Or at least 80m EV/PHEV vehicles  sold per year for around 8-9 years.

Put that way, it's like doing nothing for a decade whilst trumpeting that we are doing something.

Science / Re: Trends in atmospheric CH4
« Last post by grixm on Today at 09:34:38 AM »
A bit of a different perspective. In June/July, the methane concentration usually dips below the value from the preceding winter. However, this year, this effect was very limited. The value is barely below the last local minimum from February. The last time something similar happened was in 2014, and back then what happened next was the biggest autumn jump we've seen since the 20th century, with the winter of 2015 being around 15-16 ppm higher than the winter of 2014. Will this happen this year too?
The politics / Re: Elections 2020 USA
« Last post by vox_mundi on Today at 08:37:55 AM »
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