A sedentary walk

Let me take you for a walk through my morning absolutions. When I get up I put the kettle on, switch the computer on and go for a pee. Then I have a quick wash and make the tea. While it is brewing I sign in and open the weather charts.
My first call was into the animation from Australia about Antarctica as I can see the first news of impending earthquakes from that one. Or I could before we entered a volcanic cycle.

IDY20001.mslp-precip

http://www.bom.gov.au/australia/charts/viewer/index.shtml?type=mslp-precip&tz=UTC&area=SH&model=G&chartSubmit=Refresh+View

If I see something there I open sci.geo.earthquakes and write about whatever occurs to me. I prefer that group because there is only me in it (the other one is retarded and thinks he is a Boat-Tailed Grackle.)

In the animation above you can see a sandwich of contour lines running half way around Antarctica. I used to think that they indicated either severe tornadic storms or volcanic activity. It took me a few years to puzzle out that it meant both. I won’t go into details as the tale is told elsewhere (but remember at the time I was writing in ignorance. Always the best way IMO.)

The contours are isobars and the ring around the coast is made up of parallel lines of equal pressure. Convention uses 4 millibar intervals the only difference in warmer climates is that the pressure vents to the sky as rain filled clouds empty into the atmosphere (generally where it freezes as ice dust.) As it can’t do that in the South Pole it has to circulate until it gets enough power to run ashore.

The shoreline is about three miles high around Antarctica because the mountains are three miles high and filled with ice. I always wondered how it disposed of its storms since the continent is always covered in Anticyclonic air. I presumed that it builds up pressure with dry air by dropping the ice on the mountains. In the animation you can see that a lot of dark lines are flowing out of Antarctica. The only way that it can leave is by suction  as in a carburettor.

When it does that it merges with the wetter cyclonic stuff to produce those streamlines around the land. The wide gap. between the streamlines and the shore is where it mixes. God knows how and why that happens.

Before the volcanic cycle took over I could forecast large earthquakes quite easily from the way that the large black cyclones reached the shore. They tended to dissipate on contact and if three arrived simultaneously they would disintegrate with a coincident large earthquake wherever.

You could see them coming a mile away; they can still be seen now as the remains of tropical storms breaking through the doldrums of the tropics around the edge of the charts. They usually join the streamline these days but streamlines were relatively rare a few years back.

Next I pick up the Global version from the same site:

IDY20000.mslp-precip.gif

http://www.bom.gov.au/australia/charts/viewer/index.shtml?type=mslp-precip&tz=UTC&area=G&model=G&chartSubmit=Refresh+View.

A relatively new phenomenon (to me at least) was the recent streamlining of Arctic air in the same manner of thing that is visible around Antarctica. Until recently I never noticed it for I had assumed it was just a low pressure system reaching Siberia and running across Russia and out into the Atlantic the way that Pacific Cyclones run across North America.

It was this phenomenon that drove me on the rocks with my previous post. There is no reason for an Arctic cyclone to remain at sea, as the shore-line has far fewer glaciers and anyway, this was early May.

I assumed it would be another volcano signalling eruption. I am sure that such cyclones are from vented volcanoes. As such are substantially clean, having lost all their debris in the eruption. Such gas clouds break through the Tropopause into the Stratosphere probably merging with solar winds if the eruption is strong enough (Sudden Stratosphere Warming.)

Ash clouds seldom reach over a mile high.

Anyway I had to wait for news about an eruption. Such stuff is reported erratically because few volcanoes are constantly monitored. There was a large earthquake at one in the Aleutians this period, about 6.3 M.

Earthquakes are rated as low at 4.5 M. and lower. Only those of magnitude 4.5 M. are reported earth-wide, although Magnitude 4 ones can be registered. This is so that every recording station can report on it. Anything below a magnitude 4 is going to fail to register in too many places for accuracy. A magnitude 4 earthquake has about as much energy as an early Atomic-bomb.

IIRC everything between Mag. 5 to Mag. 6.5 is considered a medium quake.  Anything above that is “large”. I was only interested in Magnitude 7 and above, as these things are unsurvivable in most regions.

Magnitude 8+ earthquakes can be considered super-quakes. Generally when things get that active a volcano takes command. If I am expecting something interesting I will patiently wait and watch each of these charts open. Otherwise I try and get through them as quickly as reasonably possible. Just concentrating on the dark masses.

In fact I never used to follow the second animation, above, as I was unaware of what I was missing. A few months back I noticed that anticyclones in the Arctic were being sucked out through the Bering Straight and being absorbed into cyclonic systems on the Aleutian chain (Aleutian Lows.) This is quite a well known phenomena called Venturi Effect.

If you know anything about cars you will know how a carburettor works but it is also the way that sand is kept on the beach instead of falling down the continental shelves into the ocean depth. And I am sure you are all familiar with that. (Which saves me a lot of trouble explaining it.)

On a bad day I can get through all this in ten minutes or so. And my tea will have brewed and be cool enough to drink by then.

On a good day I could be lost on there for an hour or more including writing to a newsgroup, where I am studiously avoided by all but 8 or so followers (at uk.sci.weather -which I tend to avoid these days because I get upset with idiots too easily for my own good.)

Next I check out the tropical storms:

Ella Adrian

There isn’t much I can say about that but it is nice to know what is going on. A recent phenomena that occurred to me is what happens to the salt lifted off the ocean in cyclones. (All cyclones.)

Tropical cyclones are called warm core cyclones because they are so powerful yet relatively tiny. They require water temperatures of 29 degrees Centigrade to start and are easily cut off if there is a crosswind. It is not the crosswind per se but that the salt residue needs to be returned as close to the core as possible. Otherwise the temperature will drop.

Rain will not fall from tropical storms until it has frozen -and it freezes in huge pellets of hail, so the cooling effect is quite serious. However if the salt falls back warm enough the local temperature remains quite stable. If it is blown too far away… not! (Adiabatic systems.)
Which brings me to the latest addition to my collection:

111

This is where Donna was on the 5th May 2017.

10

This is what the region looks like a week later. Ella is to the right:

21

There is a triangle of warm brine residue from the once powerful storm. The idea for this idea began as a curio when I couldn’t find how much salt falls out of a storm. It turns out to be 7billion tons per day in a relatively small tropical storm but my maths is terrible and I had to work it all out myself.

And this is where Donna is still making waves:

55

But I have been working on this since I came back from the writers group at Clayton this morning and now it is nearly seven thirty pm. So I am going to close this thread and publish it to the blog.

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