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Policy and solutions / Re: Electric cars
« Last post by Sigmetnow on Today at 04:05:53 AM »
YUAN TALKS (@YuanTalks) 10/12/19, 4:07 AM
#China’s passenger car sales fell 6.6% y/y in September, down for the 3rd straight month, according to China passenger car association.

India's September passenger vehicle sales dive 24% as slowdown persists
...passenger car sales dived 33.4% to 131,281 units.
SIAM's data comes as the domestic automobile industry faces a crippling slowdown in demand that has led to production cuts and thousands of job losses. The industry is seeing its longest ever streak of sales decline.
Consequences / Re: Global Dimming - The aerosol masking effect
« Last post by TerryM on Today at 02:20:45 AM »
Good catch ;)
The rest / Re: The Trump Presidency
« Last post by TerryM on Today at 02:17:20 AM »
I have difficulty chastising any American official who opts out of a military confrontation.
It's been a long time & Bolton's probably choking on his mustache! ;D

Policy and solutions / Re: Tesla glory/failure
« Last post by TerryM on Today at 01:53:01 AM »


I don't believe we've reached the "commodity" stage just yet. & I'm not sure that we ever will. :-\

Even when restricting ourselves to the popular 18650 size of lithium cells the chemistry, voltage, combustibility, safety, and efficiency measured by weight, volume, speed of recharging, ability to discharge rapidly, number of recharges and finally costs vary widely.
I personally have been impressed by the LiFe-Po family as built by A123 in various sizes and configurations, but there are plenty to choose from, even when you restrict your usage to battery powered transportation.

Commodity pricing won't appear until the various chemistries and manufacturing processes have coalesced, but we may never reach that stage. Each cell type is a compromise and a battery cell that scores high in one metric will have other characteristics that detract from its suitability in a particular usage.

The link provides a quick overview and comparison of some of the many lithium cells available today, but it's a rapidly advancing field & what looks wonderful today may will appear terribly dated in a few years.

I don't think the horses are even at the gates yet. When they are they'll be racing off in various directions depending on what specifications are seen as most important by a particular customer on a particular day. 8)
[Edit - This discussion probably belongs in a battery thread. I hadn't noticed until after I'd posted,
If the discussion continues let's move to Batteries: Today's Energy Solution.
Consequences / Re: Global Dimming - The aerosol masking effect
« Last post by harpy on Today at 01:43:59 AM »

There's a forum in the Science section about aerosols.  We've shared many papers on the subject.

Recently, someone went to a talk by a scientist specializing in aerosols and asked about the warming that would occur if we stopped producing man-made aerosols suddenly.

Did the question about a possible spike in warming from reduced aerosols with the reduction in fossil fuel burning come up?  If so, what was the answer?

Yes, I actually asked about Hansen et al.'s 2013 paper on aerosol masking, and the effect that immediately stopping production of sulfates via oil/coal/etc. Dr. Haywood said he respected Dr. Hansen, but believed that the warming effect would not be as great or as rapid as Hansen described. Additionally, Dr. Haywood said that sulfates would be replaced with other aerosols that occur naturally, the names of which escape me.

That's not even the correct year of Hansen's paper. 
Arctic sea ice / Re: MOSAiC news
« Last post by A-Team on Today at 01:18:15 AM »
Update: the differencing of successive days of AMSR2_large is an effective way of visualizing closure of the open gap between the Polarstern and the Siberian shoreline: central ice pack edge growth meets growing landfast ice. Growth of that is just now kicking in.

I was just barely able to scale down mosaic.multisensor to overlay the Polarstern drift path on the 3.125 km resolution AMSR2; this require downsizing the radar original to 0.45% to get the path scaled (no sign of TPD yet).

There are a lot of ways to slice and dice the buoy data, the first substantial nrt data set we’ve had to work with, other than satellite products, since the ice penetrating radar archive for Greenland. In past years, 0-1 buoys have been reporting, often defectively, in the entire Arctic Ocean whereas now we have a large active coupled buoy array in the vicinity of the Polarstern..

The data archiving is still a bit rough, for example the second set of buoys below don’t measure snow depth or ice thickness as their meereisportal table indicates. However provisional graphs of temperature and speed are provided as a convenience and updated daily.

The Polarstern itself behaves as a giant buoy since being stably moored on Oct 4th. No hourly database for it accompanies the others. The radar image archive shifted to high resolution on Oct 7th. The pixel dimensions shifted inexplicably from 3500 x 4304 to 3498 x 4302 between the 7th and 9th, causing stacking issues. (Inexplicable because the crop tool has a fixed-size checkbox in all known image software.) The timestamps are all 0500 UTC; lat/lon of the Polarstern are not provided in the extensive legend.

The Sentinel images have different pixel offsets each day. Lagrangian coordinates (co-moving with ship) are being used; they cause havoc with the graticule and drift course overlay. It's more common on satellite series to use fixed eulerian coordinates to illustrate floe and lead dynamic development.

The first set of RSAQUA-type SVP buoys was deployed by Chinese scientists. These measure GPS position every hour along with temperature. From lat/lon they derived displacements (not shown) by an unknown equation (vincenty? haversine?), from which speeds were determined hourly. These buoys do not carry a wave heave accelerometer. Tides in the open Arctic are too low and slow to give a reading.

I checked into measurement error. One degree difference in latitude on the WGS ellipsoid is 111,111 meters. The GPS is reported to 1 part in 10,000, meaning 85.1234º can barely be distinguished for 85.1235º. Thus the positional uncertainty is 11.1 meters which is inadequate for a cruise missile but plausible this far north.

In calculating items like the changing sides and angles of a delaunay triangulation array, no purpose is served by exceeding the accuracy of the data.

It appears the buoys do not track azimuth. That is, unlike a ship, there is no natural axis unless the floe itself is stably asymmetric. Rotation of the floe in which the buoy is frozen is thus difficult to disentangle from translation.

We have measured large floes spinning around and around in the Beaufort arm eddies in previous autumns. In the vicinity of the Polarstern, the ice is mainly moving en bloc. The arm is forming nor this month and will likely extend up the Alaskan coast to the Chukchi before turning north. The ice will not move in a gyre, it hasn't for over a decade.

A column for changing bearing angle can be added using batch online tools (or spreadsheet formula). I did this for 2019P152 using positions 24, 48 and 72 hours apart; to the extent calculated bearings change more than the track implies, the floe has rotated. Bearing, heading and course are a source of perpetual confusion but see:

There is no column for changes in drift speed (acceleration) but that is implicit as the slope of the tangent line to the speed graph (below). The one I looked at 2019 has a puzzling periodicity. Obviously if other 11 buoys don’t follow in parallel, they are diverging/converging and the ice in between is deforming.


D Watkins, a grad student at Oregon State who studies ‘Arctic lower tropospheric temperature inversions in the CESM large ensemble’ deployed a second set of nine buoys (brand not provided) from the helicopter of the Akademik Federov.

2019P188  2019P196
2019P190  2019P198
2019P191  2019P200
2019P192  2019P203  2019P206

These buoys apparently do have an onboard accelerometer, though the column heading is "accelometer_variance ()" with units omitted but values ranging from 5 to 15. It’s not clear why the buoy should expect any waves in the next 8 months. I tracked down an explanation of sorts from NDBC not specific to this particular buoy:

How are spectral wave data derived from buoy motion measurements?

NDBC-reported wave measurements are not directly measured by sensors on board the buoys. Instead, the accelerometers or inclinometers on board the buoys measure the heave acceleration or the vertical displacement of the buoy hull during the wave acquisition time. A Fast Fourier Transform (FFT) is applied to the data by the processor on board the buoy to transform the data from the temporal domain into the frequency domain. Note that the raw acceleration or displacement measurements are not transmitted shore-side. Response amplitude operator (RAO) processing is then performed on the transformed data to account for both hull and electronic noise. It is from this transformation that non-directional spectral wave measurements (i.e., wave energies with their associated frequencies) are derived. Along with the spectral energies, measurements such as significant wave height (WVHGT), average wave period (AVGPD), and dominant period (DOMPD) are also derived from the transformation.
The rest / Re: The Trump Presidency
« Last post by vox_mundi on Today at 01:17:32 AM »

Turkey’s conflict in Syria took a major turn today. First alleged atrocities by Turkish-backed Arab militias, executing Kurds. US military officials tell me it's true, and they are DEEPLY concerned it opens the door to BOTH ethnic cleansing of Kurds and return of ISIS/Al-Qaeda.


There is no plan. There is no moral compass; There is no higher cause. There is only power and re-election.
The rest / Re: Unsorted
« Last post by TerryM on Today at 12:36:38 AM »
My understanding is that some theology(s?) require some males to wrap a turban about their head at some times &/or on some occasions, &/or in some locations -  and I don't want to brush these under the rug since a properly fitted turban should aleviate any need for wearing a rug.
 My own languidly grasped theology requests the wearing of a Traditional Tin Colander only on such occasions when it is felt that donning the Divine Device will cause discomfort to Theologists, Licensing Photographers, Lawyers & Lawmakers. The wearing of the TTC is "Always Admired, but Never Required".TM

We believe that allowing our pate to be Directly & Divinely Enwrapped by His Noodley Appendage while Enraptured, then toweling off and disposing of any Divinely Deposited Wholly Cheesy Sauce is certainly more Symbolically Sanitary than wearing a Symbolically Saturated Saucy Towel while amongst the Pagan Public. Single Service Paper Towels serve to remind The Faithful of the Glorious Piracy of Lumber Barons, whose lifestyle many of our Pirate Prophets Aspired Too Emulate.

Paper Towels/Turbans it should be noted could sequester carbon for long periods if they were but properly preserved and venerated as the sacred relics that they certainly represent, at least among those estranged from the FSM.

'Pastafarian' Photographed in Driver's License Wearing ...

Policy and solutions / Re: Ships and boats
« Last post by vox_mundi on Today at 12:24:01 AM »
Why Lightning Strikes Twice as Often Over Shipping Lanes

Thunderstorms directly above two of the world’s busiest shipping lanes are significantly more powerful than storms in areas of the ocean where ships don’t travel, according to new University of Washington research.

... Under normal conditions, microscopic water droplets in the air grab onto “cloud condensation nuclei,” which are aerosol particles bigger than 50 nanometers, like a bit of dust, or sulphur dioxide. When few particles are present, each one picks up more droplets, and they coalesce into relatively short clouds at low altitudes. Those make rain. When a lot of aerosol particles are present, each one gets fewer droplets and can float high enough into the atmosphere to freeze. In the resulting tall clouds, those bits of ice and slush run into each other and transfer electric charges. The differences in charge creates an electric field, which results in lightning.

The official term for this is “aerosol convective invigoration.” Thornton also calls it “catalyzing lightning.” You just need to know that more particles means more lightning, and burning fossil fuels is a reliable way to make those particles. Ships are especially culpable because they use bunker fuel to get from port to port. Made from the dark, viscous stuff that’s left at the bottom of the barrel after the comparatively ethereal gasoline, jet fuel, and kerosene have been distilled off, it contains about 3,500 times as much sulphur as automotive diesel. The world’s fleet burns some 3.3 million barrels of it daily. (At least until December 31—more on that in a flash.)

For the 2017 study, Thornton and his coauthors pulled data on 1.5 × 10^9 individual strokes (aka discharges) between 2005 and 2016 from the World Wide Lightning Location Network. They compared that to data from the Emissions Database for Global Atmospheric Research, which makes detailed estimates on how much pollution ships create based on real-time info. Then, in 2018, University of Washington researchers Peter Blossey and Christopher Bretherton followed up by using a computer simulation to measure the effect of ship emissions in the Indian Ocean on cloud creation, in response to the 2017 study. With support from Thronton and Virts (now at NASA), they found effects on thunderstorms that lined up with the original study.


Thousands of Ships Fitted With “Cheat Devices” to Divert Poisonous Pollution Into Sea

Diagram showing an open-loop Marine Exhaust Gas Cleaning System that removes sulfur and nitrogen compounds from a ship’s engine exhaust and dumps them into the surrounding water. Graphic: Tritech Engineers

... “In the North Sea and some parts of the Channel, the water quality has already been heavily degraded”
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Last post by AbruptSLR on October 12, 2019, 11:34:09 PM »
This post is the last of my recent series of posts on mechanisms that may likely lead to local ice-cliff failures occurring in the trough of the bed of the Thwaites gateway after the TEIS and the Thwaites Ice Tongue may have collapsed circa 2030/35:

The first image reminds us of the geometry of the bed topology and the subglacial cavity in the Thwaites gateway; which makes the Thwaites Glacier uniquely susceptible to an MICI-type of collapse in the coming decades.

The second image shows how snow fall primarily in the coastal areas of the West Antarctic; where it progressively increases the gravitational driving force on key marine glaciers in the ASE like the Thwaites Glacier.

The third image shows that the eastern shear margin of the Thwaites Glacier is linked to the SW Tributary Glacier.  Thus now that the calving front of the Pine Island Ice Shelf, PIIS, has retreated upstream of the ice shelf for the SW Tributary Glacier, we can expect that the associated acceleration of the ice velocities of the SW Tributary Glacier will reduce the buttressing of the eastern shear margin; which should accelerate the ice flow velocities of the Thwaites Glacier in coming decades.

The fourth image of a 'Domino Wave' reminds us that a cascade of tipping points associated with the stability of the Thwaites Glacier can accelerate rapidly once triggered.
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