Treating scientists as bags of mostly water

By: Dr. Jeff Masters , 4:01 PM GMT on December 26, 2007

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During the holiday season, it's natural to ask philosophical questions such as, "what is the essence of being human?" Well, one way to answer that question is purely scientifically. Humans are mostly water (ugly bags of mostly water, according to Microbrain, Stardate 41463.9, Star Trek: The Next Generation,, Episode 17). More than half the human body is made up of water, and we can use that fact to measure how many humans are present at large gatherings. Such an experiment was performed at the 2006 American Geophysical Union (AGU) meeting in San Francisco, as reported in a November 2007 paper by Darin Desilets et al. of the University of Arizona. The experiment made use of the fact that cosmic rays are continually bombarding the earth, creating fast neutrons as a by-product of nuclear disintegrations. When these neutrons encounter large concentrations of hydrogen (such as found in ugly bags of mostly water), they get scattered. One can look at the resulting scattering pattern and deduce how much hydrogen is present, and make an estimation of the number of people present.


Figure 1. Ugly bag of mostly water (and co-founder of the Weather Underground) Perry Samson (right) poses in front of his Poster at the 2007 AGU meeting. Also pictured: Russ Rew and Mohan Ramamurthy of Unidata. Fast cosmic ray neutrons scattered from their bodies were used to help estimate the number of people present at the 2006 meeting.

The equipment needed to do so costs about $10,000, and was set up in the Moscone Convention Center in San Francisco during the 2006 AGU meeting. The scientists were able to show when lunch breaks occurred by pointing out a sharp reduction in neutron scattering when all the scientists filed out to grab a bite to eat. Desilets et al. estimated about 1,700 scientists were present in the Exhibit Hall of the convention center during the height of the conference, which is probably a reasonable estimate, given the stated capacity of 3575 people. The technique can also be used to perform measurements of water content of snow and soil, and Desilets et al. advertise that they are open to paid invitations to count crowds at Rio de Janerio's Carnival, Pamplona's running of the bulls, and the next World Cup Finals.

Happy New Year, everyone! I'll be back with a new blog on January 2.

Jeff Masters

References
Desliets, D., M. Zreda, T. Ferre, 2007, Scientist Water Equivalent Measured With Cosmic Rays at 2006 AGU Fall Meeting, EOS, TRANSACTIONS AMERICAN GEOPHYSICAL UNION, VOL. 88, NO. 48, PAGE 521, 2007.

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511. Cavin Rawlins
5:52 PM GMT on December 29, 2007
Jeff Masters has a new blog
Member Since: July 24, 2005 Posts: 407 Comments: 19076
510. Tazmanian
5:24 PM GMT on December 29, 2007
493. StormW 8:43 AM PST on December 29, 2007
477. Weather456 11:23 AM EST on December 29, 2007
So taz to answer ur question

4960m is about the 300 mb level.

I can tell you that some past upper lows at that intensity have had -46C at 300 mb. If you were to bring that down to the surface using a standard adiabatic lapse rate..that would be 2C at the surface.

Now factor in the Oceanic Modifier, WAA, vegetation and the forecast snow cover. Then compare it with average.

10-20C near the coast and low valleys of CA
below Zero at higher elevations

Or, for a real general comparison...figure the 540 or 5400 line usually depicts the freezing line (0C or 32F)

thanks
Member Since: May 21, 2006 Posts: 5091 Comments: 115074
509. 1900hurricane
5:20 PM GMT on December 29, 2007
This shows the storms's evolution very well

MIMIC-TPW
Member Since: August 2, 2006 Posts: 46 Comments: 11667
508. Drakoen
5:15 PM GMT on December 29, 2007
Member Since: October 28, 2006 Posts: 57 Comments: 30489
507. Cavin Rawlins
5:13 PM GMT on December 29, 2007
Infrared Imagery with surface temps overlay

M represents a station, buoy or ship that did not reported in the last 2 hrs. From the few observations...uniform surface temps.

Member Since: July 24, 2005 Posts: 407 Comments: 19076
506. Drakoen
5:07 PM GMT on December 29, 2007
Good observation W456. Given the strong inflow at the surface and the upper level trough carrying moisture from South America (through upper level diffluence) is helping the system.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
505. 1900hurricane
5:02 PM GMT on December 29, 2007
Thanks for the link!

: )
Member Since: August 2, 2006 Posts: 46 Comments: 11667
504. Cavin Rawlins
5:02 PM GMT on December 29, 2007
AMSU-E Microwave Data showing cloud liquid water.
Notice how 95L is taping into tropical moisture.

Member Since: July 24, 2005 Posts: 407 Comments: 19076
503. Drakoen
5:00 PM GMT on December 29, 2007
I know you guys like the SSD site but now that its down (what a surprise!) i have water vapor imagery that you can use. I think its sometimes better that the SSD site.
Link
Member Since: October 28, 2006 Posts: 57 Comments: 30489
502. 1900hurricane
4:59 PM GMT on December 29, 2007
Here's an interesting loop that shows the evolution of the storm.

Link
Member Since: August 2, 2006 Posts: 46 Comments: 11667
501. extreme236
4:59 PM GMT on December 29, 2007
95L looks kind of like a comma, Andrea looked like a doughnut.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
500. Drakoen
4:58 PM GMT on December 29, 2007
I think i will do a blog update on it later in the after noon.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
499. 1900hurricane
4:56 PM GMT on December 29, 2007
Really? I must be looking at it differently then...
Member Since: August 2, 2006 Posts: 46 Comments: 11667
498. Drakoen
4:56 PM GMT on December 29, 2007
497. extreme236 4:54 PM GMT on December 29, 2007
Hmm, I dont think it looks that much like Andrea...


me either lol.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
497. extreme236
4:54 PM GMT on December 29, 2007
Hmm, I dont think it looks that much like Andrea...
Member Since: August 2, 2007 Posts: 19 Comments: 19234
496. 1900hurricane
4:50 PM GMT on December 29, 2007
It looks like Andrea before going subtropical.

Member Since: August 2, 2006 Posts: 46 Comments: 11667
495. Cavin Rawlins
4:46 PM GMT on December 29, 2007
Member Since: July 24, 2005 Posts: 407 Comments: 19076
494. Drakoen
4:46 PM GMT on December 29, 2007
I'm hoping the NHC gives it special feature status, so we can get a better idea of what they are thinking rather than having to go to the Atlantic discussion for some general information.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
492. Cavin Rawlins
4:42 PM GMT on December 29, 2007
Organization cant get no better than this:

I'm going to get some microwave data for this.

Member Since: July 24, 2005 Posts: 407 Comments: 19076
491. Drakoen
4:39 PM GMT on December 29, 2007
updated shear map. Notice how the 20knot isotach crosses over the low and to the west shear is only 5-10 knots which is the region it needs get to for significant development to occur. The streamlines show westerly shear.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
490. 1900hurricane
4:39 PM GMT on December 29, 2007
I can see that we now have a nice collection of images to work with... so how about one more?

Member Since: August 2, 2006 Posts: 46 Comments: 11667
489. Drakoen
4:36 PM GMT on December 29, 2007
.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
488. Drakoen
4:34 PM GMT on December 29, 2007



Member Since: October 28, 2006 Posts: 57 Comments: 30489
486. 1900hurricane
4:33 PM GMT on December 29, 2007
Single image from EUMETSAT

Member Since: August 2, 2006 Posts: 46 Comments: 11667
485. 1900hurricane
4:28 PM GMT on December 29, 2007
The CMC has actually been advertising this low for about a week and a half now.
Member Since: August 2, 2006 Posts: 46 Comments: 11667
484. extreme236
4:28 PM GMT on December 29, 2007
Of course, -50 to -60 degrees celsius isnt as warm as one would think when you consider low SSTs. But yes, the coldest cloud tops are displaced away from LLC.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
483. 1900hurricane
4:26 PM GMT on December 29, 2007
475. Drakoen 10:19 AM CST on December 29, 2007
You guys should use eumetsat to track the system you get a good view of the system and the surround feature. Put in on sector 1.


Here is a link
Member Since: August 2, 2006 Posts: 46 Comments: 11667
482. Drakoen
4:26 PM GMT on December 29, 2007
Notice how the coldest cloud tops are only -50 to -60 degrees and are displace from the center. Another indication of a subtropical cyclone.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
481. Cavin Rawlins
4:25 PM GMT on December 29, 2007
It pays to stay around.....many of us saw the low since Monday.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
480. Drakoen
4:24 PM GMT on December 29, 2007
the SDD imagery has not update since sunrise over the system. Its best to use RAMSDIS and EUMETSAT imagery.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
479. extreme236
4:24 PM GMT on December 29, 2007
All the SSD images are 0945UTC
Member Since: August 2, 2007 Posts: 19 Comments: 19234
478. extreme236
4:23 PM GMT on December 29, 2007
Yea, EUMETSAT will be good since I cant seem to get the SSD image to update.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
477. Cavin Rawlins
4:23 PM GMT on December 29, 2007
So taz to answer ur question

4960m is about the 300 mb level.

I can tell you that some past upper lows at that intensity have had -46C at 300 mb. If you were to bring that down to the surface using a standard adiabatic lapse rate..that would be 2C at the surface.

Now factor in the Oceanic Modifier, WAA, vegetation and the forecast snow cover. Then compare it with average.

10-20C near the coast and low valleys of CA
below Zero at higher elevations.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
476. 1900hurricane
4:22 PM GMT on December 29, 2007
Cyclone looks interesting on RGB.

Member Since: August 2, 2006 Posts: 46 Comments: 11667
475. Drakoen
4:19 PM GMT on December 29, 2007
You guys should use eumetsat to track the system you get a good view of the system and the surround feature. Put in on sector 1.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
474. Drakoen
4:19 PM GMT on December 29, 2007
The system does have a good structure. There are no frontal boundaries attached. The convecition is consolidating around the low pressure system. The 850mb positive vorticity maximum has become stronger relative to the mid and upper level vorticity. Wind shear has decrease by 5 knots in the systems path. The most important part now is for the system to become vertically stacked. The mid level center is only one degree north of the surface center.
Member Since: October 28, 2006 Posts: 57 Comments: 30489
473. extreme236
4:16 PM GMT on December 29, 2007
Well to me, its about time they have the season extended further into December.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
472. HurricaneGeek
4:15 PM GMT on December 29, 2007
Wow, so this is Dec. 29th and the tropics still are running....
Member Since: May 10, 2007 Posts: 110 Comments: 7039
470. 1900hurricane
4:15 PM GMT on December 29, 2007
The sat presentation of the storm reminds me a bit of Andrea before she became subtropical.
Member Since: August 2, 2006 Posts: 46 Comments: 11667
469. extreme236
4:14 PM GMT on December 29, 2007
95L already looks like a cyclone on the image you posted Drak.
Member Since: August 2, 2007 Posts: 19 Comments: 19234
468. Drakoen
4:13 PM GMT on December 29, 2007
Member Since: October 28, 2006 Posts: 57 Comments: 30489
467. 1900hurricane
4:12 PM GMT on December 29, 2007
465. Weather456 10:09 AM CST on December 29, 2007
Here's an image of the storm on December 26.


It sure has come a long way from where it was then to where it is now.
Member Since: August 2, 2006 Posts: 46 Comments: 11667
466. Cavin Rawlins
4:11 PM GMT on December 29, 2007
464. StormW 12:07 PM AST on December 29, 2007 Hide this comment.
457. Weather456 10:38 AM EST on December 29, 2007
449. Tazmanian 11:20 AM AST on December 29, 2007 Hide this comment.
456 how cold is a 496DM low?

whats "496DM"?

That would be 496 DecaMeters, or 4960 meters (thickness).


oooo I see....Thanks

I thought the US doesnt use the metric system.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
465. Cavin Rawlins
4:09 PM GMT on December 29, 2007
Here's an image of the storm on December 26.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
463. Cazatormentas
3:59 PM GMT on December 29, 2007
Oh...! ZETA...

By the way, did you see the last cyclone phase based on GFS? It is carrying the low to the hot area of the diagram; yesterday, the diagram put the low over the shallow warm core area... today, it puts the low over the moderate warm core area... Very interesting.

Moreover, it is located over 23-25ÂșC waters.

Wikipedia (not very accurate in many cases I think...) says that about subtropical cyclones development: The mode of the sea surface temperatures that subtropical cyclones form over is 23 degrees Celsius.

It would be very nice to see PABLO developing at this time!

Sorry for my poor English. Salutations from Spain.

I share with you a link to a forum in which we are monitoring the progress of that system (in Spanish, sorry): Link
Member Since: October 18, 2007 Posts: 0 Comments: 149
462. weatherblog
3:56 PM GMT on December 29, 2007
Hey, guys.
I've got a new blog about 95L:
Link
Member Since: July 10, 2006 Posts: 27 Comments: 1623
461. Cavin Rawlins
3:52 PM GMT on December 29, 2007
Tropical Cyclone Melanie

1430 UTC DEC 29 2007

Pattern: Extremely large and well define deep cloud overcast. Curve band is seen at 1.05 arc.

Current Intensity: CI 3.8/60/980

Adjustments: None

Final Estimate: CI 3.8

Dvorak Trends:
0000 UTC DEC 25 2007 - CI 1.5
1230 UTC DEC 26 2007 - CI 1.5
2200 UTC DEC 26 2007 - CI 1.5
1157 UTC DEC 27 2007 - CI 1.5
2030 UTC DEC 27 2007 - CI 1.8
0000 UTC DEC 28 2007 - CI 2.0
1000 UTC DEC 28 2007 - CI 3.0
2030 UTC DEC 28 2007 - CI 3.7
1030 UTC DEC 29 2007 - CI 3.5
1430 UTC DEC 29 2008 - CI 3.8




Member Since: July 24, 2005 Posts: 407 Comments: 19076

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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