Signal Butte

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Signal Butte

Postby Scott Patterson » Sat Apr 21, 2018 10:50 am

The note on LOJ says the following on prominence of Signal Butte (299 feet of listed prominence):

May be ranked if spot elevation 6223 at the saddle is not the lowpoint.

https://listsofjohn.com/peak/6280

For anyone interested, a handheld GPS reading says 302 feet, but this probably not considered to be definitive enough to make it an officially ranked peak.
Last edited by Scott Patterson on Wed Apr 25, 2018 8:37 am, edited 1 time in total.
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Re: Signal Butte

Postby JoeGrim » Tue Apr 24, 2018 1:16 pm

The problem is that there are uncertainties with GPS measurements. For example, if you walked 10 times around a flat 1/4-mile track, your GPS would indicate plenty of little ups and downs. Factors influencing how big these ups and downs include: the model of GPS device, how recently the GPS was turned on (newer devices self-calibrate after being turned on), the wind speed (affects the barometric altimeter via Bernoulli's principle), blockage of satellite signals (by foliage, terrain, and even your body), current weather (e.g., more humidity in the atmosphere degrades and slows the speed of the signal), current positions of satellites in the sky, solar storms, battery charge, and I'm sure there are plenty of other things. These uncertainties can sometimes be as low as 5 feet, or can be 100 feet or more. Therefore, last I knew, John does not use GPS readings to determine prominence. Your 302' GPS-indicated prominence definitely provides circumstantial evidence, but the 2' of prominence above 300' is definitely within the most conservative of error bars. Maybe if you hike it another 9 times, and each of those hikes indicate 300+' prominence, that might be enough? Anyway, it's great you've bagged this peak, in case it one day is found to be ranked. It looks like an awesome spot!
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Re: Signal Butte

Postby JoeGrim » Tue Apr 24, 2018 1:19 pm

By the way, it's interesting both you and I were atop Mariana Butte yesterday, yet we've never (to my knowledge) met.
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Re: Signal Butte

Postby Scott Patterson » Wed Apr 25, 2018 7:28 am

Therefore, last I knew, John does not use GPS readings to determine prominence.


I agree. There was a typo in my post. I meant to say that this is not enough evidence to make it a ranked peak. The reading does point out though that the spot elevation marked is close to the low point of the saddle, which was questioned when the list was made. If the GPS reading was 30 feet of extra prominence or something that might be different.

As far as ranked go, I would have climbed it either way (I climb plenty of unranked peaks), but if anyone did do all the 6ers (if that ever happens), it would be a good idea to climb it just in case.

JoeGrim wrote:By the way, it's interesting both you and I were atop Mariana Butte yesterday, yet we've never (to my knowledge) met.


I am staying at the La Quinta near Mariana Butte, so I sometimes hike those trails at night. Usually I only go up there after dark so don't see anyone.
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Re: Signal Butte

Postby John Kirk » Tue May 08, 2018 9:46 am

Key here is if the lat/lon of the lowpoint in the saddle is not a match with the spot elevation lat/lon shown on the map - then it becomes indisputable that a lower saddle elevation should be used, and therefore the peak would be considered ranked.
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