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#1728 - 01/14/10 08:01 PM Re: 14,505 ? [Re: Steve C]
Rod Offline


Registered: 09/22/09
Posts: 660
Loc: Santa Clarita, Ca. USA
Axeman that is an incredible shot.Reminds me that when we take xrays we have to take 90 degree secondary views as the change of position reveals new and unseen information.Your 180 degree shot of Whitney from the west reveals a view of MW many have never seen. It looks like a completely different mountain.It also reveals subtlely the difference of the Western Sierras vs the Eastern Sierras


Edited by Rod (01/14/10 08:04 PM)

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#1810 - 01/21/10 11:12 PM Re: 14,505 ? [Re: Steve C]
dbd Offline


Registered: 11/09/09
Posts: 200
Loc: San Diego
Modern surveys, including the most recent of Mt Whitney determine the position of the top of Whitney in meters from the center of the earth in three axes (x, y, z). Elevations are the differences between the position of the peak and the position of a zero-elevation reference surface between the peak and the center of the earth.

The current official form of the reference surface is known as a geoid. The recent changes to the elevation of Mt Whitney are due to increasingly accurate measurement of the position of the geoid and not to changes in the position of the peak of Mt Whitney relative to the center of the earth. The geoid models have been updated recently because there are regions with changes in the position of the geoid referenced to "fixed" markers and because the achievable accuracy in calculating the geoid has increased.

The current system of vertical controls: NAVD88 (North Amaricam Vertical Datum 88) was based on surveyed extensions of sea level based on sites where there were seas available to measure. Since then, more accurate methods based on gravitic measurements have been used to correct and update the surveyed values.

Last June in the Webcam thread on WPSMB I quoted the NGS Whitney site accessed June 12, 2009 quoted below. It used a model called Geoid03 as the current vertical reference. Since then the geoid has been updated to Geoid09 as can be seen in the section of NGS data for Whitney accessed on Jan 21, 2010. The difference of 0.08 meters does not alter the 14,505' elevation value for Whitney.

The following urls provide more general and specific information of the topic and Mt

Whitney.

General Info.:

http://answers.google.com/answers/threadview/id/260547.html
http://www.dot.ca.gov/hq/row/landsurveys/SurveysManual/04_Surveys.pdf
see figure 4-1 on page 4-6
http://www.absoluteastronomy.com/topics/Mount%20Whitney
see Geography - Elevation Measurements

Recent Updates to NAVD88:

http://www.ngs.noaa.gov/GEOID/GEOID03/
http://www.ngs.noaa.gov/GEOID/GEOID09/
http://www.ngs.noaa.gov/GEOID/USGG2009/faq_2009.shtml


Whitney data Posted to WPSMB webcam thread June 29, 2009:

1 National Geodetic Survey, Retrieval Date = JUNE 12, 2009
GT1811 *****************************************************************
GT1811 DESIGNATION - WHITNEY
GT1811 PID - GT1811
GT1811 STATE/COUNTY- CA/INYO
GT1811 USGS QUAD - MOUNT WHITNEY (1994)
GT1811
GT1811 *CURRENT SURVEY CONTROL
GT1811 ___________________________________________________________________
GT1811* NAD 83(1992)- 36 34 42.89133(N) 118 17 31.18182(W) ADJUSTED
GT1811* NAVD 88 - 4421.0 (meters) 14505. (feet) VERTCON
GT1811 ___________________________________________________________________
GT1811 EPOCH DATE - 1991.35
GT1811 LAPLACE CORR- -9.63 (seconds) DEFLEC99
GT1811 GEOID HEIGHT- -25.24 (meters) GEOID03

Recent access to NGS Whitney data:

1 National Geodetic Survey, Retrieval Date = JANUARY 21, 2010
GT1811 ***********************************************************************
GT1811 DESIGNATION - WHITNEY
GT1811 PID - GT1811
GT1811 STATE/COUNTY- CA/INYO
GT1811 USGS QUAD - MOUNT WHITNEY (1994)
GT1811
GT1811 *CURRENT SURVEY CONTROL
GT1811 ___________________________________________________________________
GT1811* NAD 83(1992)- 36 34 42.89133(N) 118 17 31.18182(W) ADJUSTED
GT1811* NAVD 88 - 4421.0 (meters) 14505. (feet) VERTCON
GT1811 ___________________________________________________________________
GT1811 EPOCH DATE - 1991.35
GT1811 LAPLACE CORR- -10.35 (seconds) USDV2009
GT1811 GEOID HEIGHT- -25.32 (meters) GEOID09
GT1811 HORZ ORDER - SECOND
GT1811

Dale B. Dalrymple

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#1812 - 01/22/10 03:41 AM Re: 14,505 ? [Re: dbd]
Wayne Offline
deceased

Registered: 11/01/09
Posts: 45
Loc: Charlotte, NC
Thanks, Dale. Looks like a good explanation. The earth-model scientists use is full of challenges and incredibly complicated.

Another way to look at this is to NOT look at Mt. Whitney pushing up to 14,505 feet, but that "sea level" (the geoid) has been measured downward, which makes Whitney and every other mountain higher. As your explanation shows, however, it is a lot more complicated than sea-level (the geoid) being measured down, but a combination of scientific measurements and modeling the earth's spheroid, and, on top of everything else, Whitney has risen and is rising, but at at a very tiny rate.

Who is the authority on mountain heights? I believe the US Geological Survey has the final word, but when changes are made, maps and other products are all impacted, let alone market products that Doug Sr. sells in his store that say something else. We don't want to be confused by the facts, right?


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#1816 - 01/22/10 08:43 AM Re: 14,505 ? [Re: Wayne]
Steve C Offline


Registered: 09/22/09
Posts: 7191
Loc: Fresno, CA
Dale, I sure appreciate your adding all the useful information to the explanation. The diagram in the absoluteastronomy.com that you referred to helps me to grasp the situation.

It's crazy to think that even sea level isn't exactly the same all around the world due to variations in gravity.

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#1823 - 01/22/10 11:45 AM Re: 14,505 ? [Re: AxeMan]
RoguePhotonic Offline


Registered: 12/08/09
Posts: 558
Loc: Bakersfield CA
So have any peaks in California been now recalculated to be over 14,000 feet?

One like Mt. Barnard at 13,990 feet.
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#1826 - 01/22/10 01:30 PM Re: 14,505 ? [Re: RoguePhotonic]
CMC2 Offline


Registered: 11/04/09
Posts: 160
Loc: CO
I keep hoping Barnard gets back over 14,000' as it was considered a 14er way back in 1958 when I lst climbed it.

But of course since 1958 I too have shrunk in height so I
guess it is a fair trade off.

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#3958 - 05/03/10 11:06 AM Re: 14,505 ? [Re: CMC2]
Steve C Offline


Registered: 09/22/09
Posts: 7191
Loc: Fresno, CA
Can anyone figure out where Doug came up with the 14,508 in his post today?

Quote:
14508'

Hi Most current elevation of Mount Whitney. Some are still using the bench of 1405 that is about 4' lower . And one group is still holding the 14,497.61 .Thanks Doug


Ok, I see the 14508 on Datasheet GT1810

At this rate, Mt. Barnard will be 14,000 again.


Edited by Steve C (05/03/10 12:46 PM)

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#3959 - 05/03/10 01:09 PM Re: 14,505 ? [Re: Steve C]
+ @ti2d Offline


Registered: 10/22/09
Posts: 799
Loc: Oh Cursed, USA
The way me sees it...

If I stood on top of Mecca West, then...

numbers don't matter much...

I WAS UP THERE AND DID NOT FALL THERE!!


Have fun.
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#3960 - 05/03/10 01:18 PM Re: 14,505 ? [Re: Steve C]
Bob R Offline


Registered: 10/27/09
Posts: 129
Loc: Ridgecrest, California
I recently acquired a 1937 Mt. Whitney topo map showing Mt. Barnard at 14,003'. So I put all my newer ones in a box deep in the garage. Made a commitment to take the 1937 one along in early July, so will tick off another 14er at that time. I have friends clamoring to come along....

Adding it to my string of 14ers-climbed-in-a-day will be tough, though.


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#3961 - 05/03/10 01:40 PM Re: 14,505 ? [Re: Bob R]
CMC2 Offline


Registered: 11/04/09
Posts: 160
Loc: CO
So Bob I can't believe you have never done Barnard before.

Which is the shorter route, 1) Shepherd Pass and the Rockwell cutoff down to Wright Basin OR 2) up North Fork, down Russell/Carillon col to Wallace Basin in order to do a 1-day (more like a 24 hr day) trip?? OR maybe a Vacation Pass approach from the East?

Sounds interesting and I am sure you will attract many friends. Wish I lived closer and could join the group.


Edited by CMC2 (05/03/10 01:42 PM)

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#3962 - 05/03/10 01:57 PM Re: 14,505 ? [Re: Steve C]
Anonymous
Unregistered


Originally Posted By: Steve C
Ok, I see the 14508 on Datasheet GT1810
At this rate, Mt. Barnard will be 14,000 again.

I just made a post on WPSMB hopefully adding a little clarity- though I'm not convinced of the absolute numbers.

GT1810 isn't a valid elevation- it was scaled from a topo map. GT1811 is a better mark with an elevation of 14505. The note on GT1811 mentions the aluminum plaque is 3' higher for an elevation of ...14508'!

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#3969 - 05/03/10 05:59 PM Re: 14,505 ? [Re: + @ti2d]
MooseTracks Offline


Registered: 11/02/09
Posts: 582
Loc: Bishop, CA, United States
Originally Posted By: + @ti2d
The way me sees it...

If I stood on top of Mecca West, then...

numbers don't matter much...

I WAS UP THERE AND DID NOT FALL THERE!!


Have fun.


Gary, what's with all the shouting from the heights lately? Used to be yous was a chillin' jive-man... eek wink
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#3974 - 05/03/10 07:14 PM Re: 14,505 ? [Re: MooseTracks]
Bulldog34 Offline


Registered: 11/12/09
Posts: 1254
Loc: Atlanta
Originally Posted By: MooseTracks
Gary, what's with all the shouting from the heights lately? Used to be yous was a chillin' jive-man... eek wink


Methinks the 'Tude Dude is suffering from pent-up agitation from a long winter of not getting into the mountains to hike. Nothing a good 22-mile ramble to 14,500-and-some-odd feet won't cure.

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#3979 - 05/04/10 05:23 AM Re: 14,505 ? [Re: MooseTracks]
+ @ti2d Offline


Registered: 10/22/09
Posts: 799
Loc: Oh Cursed, USA
Originally Posted By: MooseTracks
Gary, what's with all the shouting from the heights lately? Used to be yous was a chillin' jive-man... eek wink


Me sufferin' from "'tude" sicknesss...

Not attitude...altitude...just expanding my alveolar sacs...

Bulldog34 right...
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#41142 - 12/10/14 12:55 AM 14,508: Mt Whitney Elevation [Re: + @ti2d]
Steve C Offline


Registered: 09/22/09
Posts: 7191
Loc: Fresno, CA
Revisited this topic, since someone asked about the Whitney elevation...

The elevation of Mt Whitney, and the various survey markers on the summit jumped in the past ten years, due to some high-tech mapping decision. I think it is related to a mapping standard called "GEOID12A".

So I did some digging, found this thread, and then looked up the various NGS "datasheet" links for the survey markers. Unfortunately, reading the text provided on the datasheet web pages is really confusing. I wish I could find a decent translation and explanation.

Here is the list I could find of the Mt Whitney markers:

ID Elev Coordinates Coordinates (converted)
GT1808 14505 36 34 42.70332 N 118 17 32.20132 W 36.5785287,-118.2922781
GT1809 14508 36 34 42.98864 N 118 17 31.18685 W 36.5786080,-118.2919963
GT1810 14508 36 34 42.98800 N 118 17 31.18625 W 36.5786078,-118.2919962
GT1811 14505 36 34 42.89133 N 118 17 31.18182 W 36.5785809,-118.2919950
GT1812 14505 36 34 43.06578 N 118 17 31.11753 W 36.5786294,-118.2919771
GT1813 14501 36 34 43.06277 N 118 17 31.11628 W 36.5786285,-118.2919767

GT0237 14502.7 36 34 45. N 118 17 31. W
GT0238 14499.2 36 34 42.99022 N 118 17 31.09025 W 36.5786084,-118.2919695
GT0239 14499.6 36 34 42.96827 N 118 17 31.25596 W 36.5786023,-118.2920155


The NGS datasheet URL for each one looks like this:
http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=GT1810
Change the GT1810 in the URL to any of the others brings up the associated page of info.

Here is the gmap4/google aerial satellite view using the converted coordinates for the GT1810 data:
http://www.mappingsupport.com/p/gmap4.php?ll=36.5786078,-118.2919962&z=20&t=s&symbol=pr
The aerial view shows where the survey marker is located on the summit.






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#41144 - 12/10/14 08:46 AM Re: 14,508: Mt Whitney Elevation [Re: Steve C]
wbtravis Offline


Registered: 09/22/09
Posts: 1239
Loc: Corner of Jack Benny and Roche...
The damn mountain grew 11' since the first time I did it...wow!

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#41145 - 12/10/14 11:10 AM Re: 14,508: Mt Whitney Elevation [Re: wbtravis]
Wiff Offline


Registered: 07/23/14
Posts: 24
Loc: LA
We should start a stack of rocks up at the top. We could get this thing over the 14,510 mark in no time.

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#41146 - 12/10/14 01:24 PM Re: 14,508: Mt Whitney Elevation [Re: Wiff]
Harvey Lankford Offline


Registered: 11/10/09
Posts: 979
Loc: Richmond, Virginia
Originally Posted By: Wiff
We should start a stack of rocks up at the top. We could get this thing over the 14,510 mark in no time.

Wasn't there a movie like that?
The Englishman Who Went Up A Hill But Came Down A Mountain

Dale's explanation (in partial Greek) about the distance from the center of the Earth reminds me that the Earth is an oblate spheroid,
therefore the 20,564-foot ft equatorial peak Chimborazo is higher than Everest. Depends on what your definition of is is.

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#41264 - 12/31/14 07:42 AM Re: 14,508: Mt Whitney Elevation [Re: Harvey Lankford]
SierraNevada Offline


Registered: 09/05/11
Posts: 1097
Loc: NorCal
The horizontal control is second order, which locates the marker within a centimeter, but the vertical control is not so well established.

The DATASHEET says, "The orthometric height was scaled from a topographic map."

And it does appear to be on a rock (the highest point on the summit), if not a pile of rocks:

"THE MARK IS A UNITED STATES GEOLOGICAL SURVEY ALUMINUM DISK,
STAMPED 14502, CEMENTED IN A DRILL HOLE IN A 5 BY 10 FOOT
BOULDER PROJECTING 3-1/2 FEET."

A leveling survey tied to a quality benchmark is the best way to settle this. I recall seeing a thread by Doug on the MWPS forum contemplating that effort.

GPS might also be adequate, if proper techniques and correction are done. Here's an old article (1990 )but written in lay terms: Establishing Vertical Control with GPS

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#41271 - 12/31/14 08:01 PM Re: 14,508: Mt Whitney Elevation [Re: SierraNevada]
saltydog Offline


Registered: 02/03/11
Posts: 1535
Loc: Valley Ford CA!!!!
I like the way "Fourteen-Five" rolls off the tongue. Kinda like "Mile, Mile and a Half". Maybe "Fourteen-Five and Change".
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