Mt Whitney Webcam
Mt Williamson Webcam
Feature Topics
Who's Online
0 registered (), 10 Guests and 25 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
3599 Members
10 Forums
5490 Topics
50331 Posts

Max Online: 382 @ 11/07/12 05:45 AM
Page 1 of 3 1 2 3 >
Topic Options
#1701 - 01/13/10 08:48 PM 14,505 or 14,508 -- Mt Whitney Elevation?
AxeMan Offline


Registered: 01/12/10
Posts: 29
Loc: Puppetville West
I guess I never got the memo...

Top
#1703 - 01/13/10 08:54 PM Re: 14,505 ? [Re: AxeMan]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
Well, since you started the thread...

I am trying to figure out how they changed the official elevation of Mt Whitney, and if I ever get the explanation straight, I'll post a little writeup.

It has to do with where the zero-elevation point is (now it is someplace in Canada near the St. Lawrence river). And also with tying multiple elevation survey grids together.

But I haven't got my questions answered yet, and every time I ask one or two, the answers cause more. confused

Does anyone here have a handle on the elevation changes?

Top
#1704 - 01/14/10 05:50 AM Re: 14,505 ? [Re: Steve C]
wagga Offline


Registered: 10/07/09
Posts: 2243
Loc: Humbug Reach (Pop. 3)
_________________________
Verum audaces non gerunt indusia alba. - Ipsi dixit MCMLXXII

Top
#1705 - 01/14/10 07:38 AM Re: 14,505 ? [Re: Steve C]
+ @ti2d Offline


Registered: 10/22/09
Posts: 830
Loc: Oh Cursed, USA
Originally Posted By: Steve C
Does anyone here have a handle on the elevation changes?


Plate tectonics?

El Nino?

Human error?

14,505 sounds better than 14,497.61 feet...less keystrokes on the numberpad! whistle
_________________________
Have fun and enjoy the Gr8 Yd Opn.

Top
#1706 - 01/14/10 08:02 AM Re: 14,505 ? [Re: Steve C]
CaT Offline


Registered: 09/24/09
Posts: 694
Loc: Blacklick, OH (formerly SoCal)
Unless it got deleted, there was a sizeable thread on WPSMB about this, probably within the last year or two.

CaT
_________________________
If future generations are to remember us with gratitude rather than contempt, we must leave them more than the miracle of technology. We must leave them a glimpse of the world as it was in the beginning, not just after we got through with it.
- Lyndon Johnson, on signing the Wilderness Act into law (1964)

Top
#1708 - 01/14/10 08:09 AM Re: 14,505 ? [Re: + @ti2d]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
The 14,505 elevation is the National Geodetic Survey's official Mt. Whitney elevation, established in 1994.

Granted, the elevation jumped then by over 5 feet, but not by any earthquake movement. As I wrote above, it was due to readjustment of the zero elevation.

Here's the NGS datasheet on the Mt. Whitney elevation:
    14505 -- Datasheet GT1811
    14508 -- Datasheet GT1810

And here are some others on the summit -- likely a datasheet for each of those brass survey medallions you can see on the summit:
    14499.2 -- Datasheet GT0238
    14499.6 -- Datasheet GT0239
    14499.6 -- Datasheet GT1808, "MT WHITNEY SMITHSONIAN HOUSE"

CaT wrote:
> Unless it got deleted, there was a sizeable thread on the WPSMB about this, probably within the last year or two.
I don't remember that, CaT. Any chance anyone can find it?

Top
#1709 - 01/14/10 08:17 AM Re: 14,505 ? [Re: Steve C]
CaT Offline


Registered: 09/24/09
Posts: 694
Loc: Blacklick, OH (formerly SoCal)
Quote:
I don't remember that, CaT. Any chance anyone can find it?

I'll take a look (again, if it is still there...).

Edits:
It wasn't quite as extensive as I remembered, but here are two threads.

The first one begins with the post dated 6/29/09 @ 11:34pm post, which should appear at the top of your screen when the "First thread" link is clicked on, and it ends prior to the end of the thread -- with the post dated 7/2/09 @ 12:35 a.m.):

First thread

The second thread, which begins as a discussion about the elevation of Trail Crest, does eventually get into the summit elevation, and includes some links of interest.

Second thread

At the very end of the second thread, a message board discussion is referred to that was apparently had back in 2003; but I don't think the archives go back that far.

CaT


Edited by CaT (01/14/10 08:55 AM)
Edit Reason: To add further info links on subject
_________________________
If future generations are to remember us with gratitude rather than contempt, we must leave them more than the miracle of technology. We must leave them a glimpse of the world as it was in the beginning, not just after we got through with it.
- Lyndon Johnson, on signing the Wilderness Act into law (1964)

Top
#1713 - 01/14/10 09:27 AM Re: 14,505 ? [Re: wagga]
KevinR Offline


Registered: 11/03/09
Posts: 591
Loc: Manchester, NH
Originally Posted By: wagga


Interesting article. Don't know what struck me more - the amount of change over a relatively short time, or our ability to now measure it so quickly/precisely.

Top
#1715 - 01/14/10 10:09 AM Re: 14,505 ? [Re: CaT]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
Oh my...

CaT's first thread came about when Doug wrote, "Hi Great job Steve only problem is the Elevation of Whitney on the Photo is wrong, it will stay about a day and then will be deleted, Thanks Doug" That was Doug's way of saying he didn't want our picture with the 14505 elevation displayed. He has come out STRONGLY against using the 14505 elevation. Not sure why, but it probably comes from a dislike of bureaucratic decisions. His mandate caused Wayne, Dale and I to scurry around and modify HIS annotated Whitney picture with his preferred elevation. You can see the results here and here. Bottom line, he was telling us to ignore the official NGS datasheet.

The second thread also shows some misinformation by referencing a different datasheet (1808)

But that second thread does refer to a student project by Robert Nielsen to determine the elevations of Mt. Whitney, Mt. Williamson, White Mountain, and North Palisade "using high precision GPS technology." Unfortunately, they were unable to set up their equipment on Whitney due to a storm in May. According to the article, Nielson measured Whitney at 14,500 ft.

Before I am done, I'll try to track him down, and maybe he can give me more info on what the "zero elevation" factor is. Maybe he can explain it better than my other sources.

Top
#1716 - 01/14/10 10:43 AM Re: 14,505 ? [Re: Steve C]
CaT Offline


Registered: 09/24/09
Posts: 694
Loc: Blacklick, OH (formerly SoCal)
Just to clarify, I'm no expert on any of this, and only dug up and posted these threads so others could have the benefit of whatever had been discussed, since the 14,505 subject had been brought up again here. I would have no way of knowing what is correct (or not). Thanks for clarifying the information within those posts, Steve. I just find and post and leave it for others more knowledgeable to comment on it.

Interestingly, my sister-in-law bought me a "hoodie" sweatshirt back around the time I first summitted Whitney as a congratulatory gift. While I don't have a picture of it, it does prominently display the summit elevation as 14,505'. So this information has at least made it to those who make Whitney shirts.

CaT
_________________________
If future generations are to remember us with gratitude rather than contempt, we must leave them more than the miracle of technology. We must leave them a glimpse of the world as it was in the beginning, not just after we got through with it.
- Lyndon Johnson, on signing the Wilderness Act into law (1964)

Top
#1717 - 01/14/10 12:26 PM Re: 14,505 ? [Re: CaT]
AxeMan Offline


Registered: 01/12/10
Posts: 29
Loc: Puppetville West
Yes, I was more or less goofing on the height. If you do a search, you'll get many different answers:

Wikipedia = 14,505
Inyo NFS = 14,496
SEKI NPS = 14,494
Lone Pine Chamber of Commerce = 14,497.61
and the summit sign = 14,496.811

In Doug's defense (separate of his years as a surveyor), think of the cost in changing and reordering all the store & hostel stock. There's a point at which a few feet really do amount to a hill of beans...

And for my next topic: Exactly how many switchbacks are there on the trail?

[insert devil smiley here]

Top
#1718 - 01/14/10 12:28 PM Re: 14,505 ? [Re: CaT]
AxeMan Offline


Registered: 01/12/10
Posts: 29
Loc: Puppetville West
Oh, and CaT. Where's your profile pic from? Looks a lot like Sespe Gorge...

Top
#1719 - 01/14/10 01:01 PM Re: 14,505 ? [Re: AxeMan]
+ @ti2d Offline


Registered: 10/22/09
Posts: 830
Loc: Oh Cursed, USA
I motion that the picture in question on the WHA website with the numbers "14,505" be stricken from the photographic record and in place of said numbers an asterisk (*). Upon clicking said asterisk, these words in small font...

WE WERE ALL UP HERE AT LEAST ONCE!

And the aforementioned phrase will display a mural of mountaineer extraordinaires who accomplished this tremendous feat of endurance.

And at the bottom of the mural, these words...

IF WE CAN DO IT, SO CAN YOU!




Have fun..
_________________________
Have fun and enjoy the Gr8 Yd Opn.

Top
#1720 - 01/14/10 02:26 PM Re: 14,505 ? [Re: + @ti2d]
wagga Offline


Registered: 10/07/09
Posts: 2243
Loc: Humbug Reach (Pop. 3)
If you click on webcam notes on WPSMB's front page, you get the picture with a little edit...
_________________________
Verum audaces non gerunt indusia alba. - Ipsi dixit MCMLXXII

Top
#1721 - 01/14/10 02:49 PM Re: 14,505 ? [Re: AxeMan]
CaT Offline


Registered: 09/24/09
Posts: 694
Loc: Blacklick, OH (formerly SoCal)
Originally Posted By: AxeMan
Oh, and CaT. Where's your profile pic from? Looks a lot like Sespe Gorge...

Just a few miles east of Skagway, Alaska this past August.

CaT
_________________________
If future generations are to remember us with gratitude rather than contempt, we must leave them more than the miracle of technology. We must leave them a glimpse of the world as it was in the beginning, not just after we got through with it.
- Lyndon Johnson, on signing the Wilderness Act into law (1964)

Top
#1722 - 01/14/10 02:59 PM Re: 14,505 ? [Re: wagga]
+ @ti2d Offline


Registered: 10/22/09
Posts: 830
Loc: Oh Cursed, USA
DOH!

sigh...

Not what I had motioned fer...dag gone darn it!
_________________________
Have fun and enjoy the Gr8 Yd Opn.

Top
#1723 - 01/14/10 03:06 PM Re: 14,505 ? [Re: Steve C]
Mike Condron Offline


Registered: 11/05/09
Posts: 215
Loc: Now Manteca, CA
If it is 14,505' above sea level (sea level: The datum against which land elevation and sea depth are measured. Mean sea level is the average of high and low tides.) and it used to be only 14,498'+/- a tad, where did all the water go?
_________________________
Mike

Top
#1724 - 01/14/10 03:37 PM Re: 14,505 ? [Re: Mike Condron]
wagga Offline


Registered: 10/07/09
Posts: 2243
Loc: Humbug Reach (Pop. 3)
You owe me a keyboard cleaning.
_________________________
Verum audaces non gerunt indusia alba. - Ipsi dixit MCMLXXII

Top
#1725 - 01/14/10 03:43 PM Re: 14,505 ? [Re: Mike Condron]
AxeMan Offline


Registered: 01/12/10
Posts: 29
Loc: Puppetville West
Okay, so I just figured it out:
Steve's measuring from the west side and Doug's measuring from the east...

Actually, maybe this should be the main page pic:

Whitney from the west side



cool myspace layouts

Top
#1726 - 01/14/10 04:01 PM Re: 14,505 ? [Re: AxeMan]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
Cool pic! That's Whitney from the west side, with Russell in the left corner. Nice.

If I get around to changing front page pictures daily, that would be a nice one.

..and I found a little red devil for you.

So when are you going to get around to posting the Starbucks hut as your profile picture? cool


Edited by Steve C (01/14/10 04:25 PM)

Top
#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)

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


Registered: 11/09/09
Posts: 208
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

Top
#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?


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


Registered: 09/22/09
Posts: 7554
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.

Top
#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.
_________________________
FlickR

Top
#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.

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


Registered: 09/22/09
Posts: 7554
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)

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


Registered: 10/22/09
Posts: 830
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.
_________________________
Have fun and enjoy the Gr8 Yd Opn.

Top
#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.


Top
#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)

Top
#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'!

Top
#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
_________________________
Facebook

Flickr Pics

Think outside the Zone.

Top
#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.

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


Registered: 10/22/09
Posts: 830
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...
_________________________
Have fun and enjoy the Gr8 Yd Opn.

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


Registered: 09/22/09
Posts: 7554
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.






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


Registered: 09/22/09
Posts: 1251
Loc: Corner of Jack Benny and Roche...
The damn mountain grew 11' since the first time I did it...wow!

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


Registered: 07/23/14
Posts: 36
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.

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


Registered: 11/10/09
Posts: 1012
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.

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


Registered: 09/05/11
Posts: 1134
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

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


Registered: 02/03/11
Posts: 1556
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".
_________________________
Wherever you go, there you are.
SPOTMe!

Top
#41412 - 01/16/15 11:31 AM Re: 14,508: Mt Whitney Elevation [Re: saltydog]
dethMarch Offline


Registered: 06/30/11
Posts: 18
Loc: SLO
This reminds me of a conversation I had with a colleague years back, who was working in geomapping, with some very sensitive GPS equipment. She shared a shocking fact with me, that any given point on the earth's crust, is flexing up and down on a daily basis, mostly due to tidal forces - (sun and moon gravitational forces, and also in response to ocean tides). Depending on what the ground is made of, local faults, etc, it can be as much as a few centimeters. Most geological survey data doesn't take this into account, except as a "margin of error" baked-in to permanent measurements.

Top
#41439 - 01/18/15 02:19 PM Re: 14,508: Mt Whitney Elevation [Re: dethMarch]
SierraNevada Offline


Registered: 09/05/11
Posts: 1134
Loc: NorCal
This is really interesting stuff, DethMarch. Its like our planet is breathing with tides. Did you perhaps mean millimeters per day instead of centimeters? I didn't realize the earth's surface fluctuated vertically so much.

Surveying for vertical control is based on leveling back to the previous benchmark, which is within eyesight, so both points move up or down about the same amount. So the fluctuations you're describing are not detectable between points close together using standard survey methods. GPS, based on satellite measurements with a global perspective can measure the up and down movement of both points, or any point for that matter.

GPS has allowed measurement of uplift of mountain ranges, fault slip, and tectonic drift. One way this is used is in predicting the probability of an earthquake on a particular fault. The chance of an earthquake occurring is based on an average annual "slip." The horizontal movement builds up stress over the years, and then lets go suddenly.

The most active reaches of the San Andreas fault move horizontally about an inch per year, and when it lets go, it can offset up to 30 feet near the epicenter. Here's a paper describing how they measure the slip rate with GPS.

Here's a paper comparing a leveling survey network with GPS measurements in Poland.

Edited for more detail and to add another link.


Edited by SierraNevada (01/19/15 07:58 AM)

Top
#41612 - 01/27/15 04:21 PM Re: 14,508: Mt Whitney Elevation [Re: SierraNevada]
dethMarch Offline


Registered: 06/30/11
Posts: 18
Loc: SLO
In most places, millimeters. In *some* places, centimeters. (was my understanding).

Some of that also has to do with tides bringing water into the water table (and back out) on a daily basis, which causes expansion and contraction as well. I think Whitney would more likely be millimeters. Because; granite.

I should write a grant proposal to get funding to bring one of those fancy $10,000 GPS receivers up there, to collect data for a few days. Not that that would settle any arguments. laugh


Edited by dethMarch (01/27/15 04:21 PM)

Top
#41616 - 01/27/15 08:36 PM Re: 14,508: Mt Whitney Elevation [Re: dethMarch]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
> I should write a grant proposal to get funding to bring one of those fancy $10,000 GPS receivers up there, to collect data for a few days.

DO IT! You will get help from the hiking community!

Top
#53724 - 06/28/18 12:33 PM Re: 14,508: Mt Whitney Elevation [Re: Steve C]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
Updating this thread... Just curious to see whether anything has been updated or changed.

NGS (National Geodetic Survey) has an updated "Survey Marks and Data Sheets" web page, with links to an interactive map: NGS Data Explorer

Using the explorer map and zooming in on Mt Whitney, we can find the highest elevation data sheet: PID : GT1809

That Data Sheet shows the elevation of 14508.

Top
#53741 - 06/30/18 04:44 PM Re: 14,508: Mt Whitney Elevation [Re: Steve C]
SierraNevada Offline


Registered: 09/05/11
Posts: 1134
Loc: NorCal
14,508 ft is only 0.021% higher than 14.505 ft, relative to sea level, which is the hikers perspective. By surveying standards, this is a HUGE discrepancy over the relatively short horizontal distance involved. So what government agency is going to overcome the logistical and funding challenges to get the world a reasonable answer? Will a private company step up? Does anybody really care?

Top
#53743 - 06/30/18 05:45 PM Re: 14,508: Mt Whitney Elevation [Re: SierraNevada]
Steve C Offline


Registered: 09/22/09
Posts: 7554
Loc: Fresno, CA
As you're well aware, SN, there is a much worse and more pressing problem lying all over the Whitney Zone, and we've been waiting and hoping a government agency would "overcome the logistical and funding challenges to get the world a reasonable answer... Does anybody really care?"

We sure do care, but I'm not sure about the others.

Top
#53747 - 07/01/18 09:17 AM Re: 14,508: Mt Whitney Elevation [Re: Steve C]
SierraNevada Offline


Registered: 09/05/11
Posts: 1134
Loc: NorCal
Steve, I can only guess what problem is lying all over the Whitney Zone. Does it come in a plastic bag and smell like crap? Its peak season, and I'm sure people will start bringing it up again. There's a new technological breakthrough ( toilet tech ) that seems to be working well under similar conditions as Whitney. There's reason for hope.


Edited by SierraNevada (07/01/18 12:40 PM)

Top
#53787 - 07/04/18 08:46 PM Re: 14,505 or 14,508 -- Mt Whitney Elevation? [Re: AxeMan]
Eugen Offline


Registered: 01/01/18
Posts: 4
Loc: Oregon
In world system it is ONE METER. How cares?

Top
#53799 - 07/05/18 10:40 PM Re: 14,505 or 14,508 -- Mt Whitney Elevation? [Re: Eugen]
skiroc Offline


Registered: 09/08/12
Posts: 6
Loc: Cal
I've been communicating with the NGS Geodetic Advisor for the SW Region about this topic over the Spring and hope to discuss with him next week during a conference we will both be attending.

He has provided a lot of history and info on why there are so many published elevations, it is clearly a topic he is both professionally and personally interested in. In summary he makes two points:

- 14,500 ft is the most "defensible" value for Mt. Whitney using current benchmarks and datums, but the highest point of the peak is likely higher

- there will be new datums in 2022 so the references for both lat/long and elevation will be changing - Whitney and other elevations will be decreasing by (estimated) a little under 3 feet

I'll report back if I learn more.


Edited by skiroc (07/05/18 10:42 PM)

Top
#53809 - 07/08/18 07:46 PM Re: 14,505 or 14,508 -- Mt Whitney Elevation? [Re: skiroc]
SierraNevada Offline


Registered: 09/05/11
Posts: 1134
Loc: NorCal
The should sell t-shirts and other swag with velcro numbers to keep up with these changes.

Top
#53847 - 07/11/18 10:40 AM Re: 14,505 or 14,508 -- Mt Whitney Elevation? [Re: SierraNevada]
cantare Offline


Registered: 04/07/14
Posts: 17
Loc: California
What I love most about this whole elevation debate is the 1930 NPS plaque installed by someone lacking an understanding of significant figures: "14,496.811 Ft". That's an implied precision of 0.3 millimeters, or the size of a small grain of sand. laugh

Also waiting for some sufficiently large group of burly DIYers to stack, upend, or reorient any of the most prominent boulders just to mess with people. What constitutes the "summit" of a loose rockpile?

Top
Page 1 of 3 1 2 3 >