Sun/wind map for BRC?

[jasonk]

Last year I found a sun/wind map for BRC that showed exactly where the sun would be coming from at all hours, prevailing wind direction, etc. Has anyone found the same for this year?

[inventory]

The city is in the exact same orientation and less than a mile from where it was last year. So if you have a map from 2014 (which sounds awesome, can you share it?) it should still be valid for 2015.

[tatonka]

Here is a sun one.

http://suncalc.net/#/40.7846,-119.1961, ... 9.04/04:40

[Canoe]

2015
Aug 30: Sunrise 6:22 am, Sunset 7:32 pm
Sep 7: Sunrise 6:27 am, Sunset 7:24 pm

BRC Map with Prevailing Wind, Cross Winds, 2015-08-30: Sun Headings and Sun Elevations, Sunrise to Sunset by the hour.

BRC sun track 2015-08-30 low.gif

[jasonk]

BRC Map with Prevailing Wind, Cross Winds, 2015-08-30: Sun Headings and Sun Elevations, Sunrise to Sunset by the hour.

This is great Canoe, thanks! Did you make this? Using what tool?

[Canoe]

Online tool to calc sun elevation and azimuth for 2015-08-30.
Libre Office: Calc to offset azimuth to get chart angle in Draw. Draw to place lines over BRC map.
Interesting with our calander, how much Sunrise/Sunset varies from burn to burn. Angles for shade are materially the same.

[Canoe]

To make it easier to know the sun headings and "typical" winds for aligning your shade/structures, here's a transparent gif file you can place over top of the BRC map, centered on your site. (Align North)
I'm hoping the upload respects the transparency.

BRC sun headings 2015.gif

[lucky420]

Thank you Canoe. You rock!

[jasonk]

Interesting, read this in the BM blog:
The city is always laid out the same way, so you’ll always see the sun coming up behind the Man as you stand in Center Camp.

[BoyScoutGirl]

Canoe, that's a great resource - thank you for making and sharing.

One question: I see it says "descending hours within two degrees of ascending." In my mind, I'm trying to flip the angles of sun elevation around the vertical axis so the sun is getting lower and lower in the west/left as the evening wears on. But then I noticed that noon isn't vertical (presumably because of the Earth's tilt and the fact that the playa isn't on the equator?), so I guess that means the sun stays low-ish in one hemisphere of the sky throughout the day..?

I love cosmology, but astronomy has always been a huge weakpoint for me - something about the geometry baffles me.

[Canoe]

"noon isn't vertical"
Noon isn't due South either.
I don't understand it, but I didn't have to. I just had the online tool make the numbers for me and then I charted it.
I assume with the peak and South being ~1:00, that the time zone is awfully close to actual time at Gerlach, but offset by one hour from 12:00 to 1:00 for Daylight Saving Time.

The angles of elevation are calculated on hour between sunrise and sunset, but only shown in my graphic for 7am, 8, 9, 10, 11, 12 and 1pm.
Peak elevation isn't at 1pm, but it's awfully close to that (near true South). So close that we regard 1pm as peak, as the difference in elevation at 1pm vs. true peak will not be material.
The descending angles for 2pm, 3, 4, 5, 6 and 7 pm, are slightly lower than the ascending hours, but within one degree of the ascending angles, so there is no material benefit of producing a Descending Elevation Angle graphic. Angle at:
7am ~= 7pm
8am ~= 6pm
9am ~= 5pm
10am ~= 4pm
11am ~= 3pm
12pm ~= 2pm
1pm ~= peak elevation

The data:
hour Elevation Azimuth
06:21:25 0.833° 77.35°
7:00:00 6.35° 83.61°
8:00:00 17.68° 93.39°
9:00:00 28.89° 103.98°
10:00:00 39.53° 116.51°
11:00:00 48.88° 132.64°
12:00:00 55.66° 154.33°
13:00:00 58.08° 181.28°
14:00:00 55.17° 207.89°
15:00:00 48.05° 228.98°
16:00:00 38.53° 244.67°
17:00:00 27.8° 256.94°
18:00:00 16.55° 267.4°
19:00:00 5.21° 277.14°
19:32:22 0.833° 282.39°

And I see that I should have looked closer, as my one degree claim is incorrect. It's slightly more than one degree for the lowest two pairs.

[Jo Z]

This map is really helpful, thanks a lot

[Canoe]

If you're out of the camp wheel area when a wind blows the dust across the playa, the dust picked up means you can't see sideways. But if it's not a big blow, you can often see upwards as the dust stays near the ground. If can see where the sun is, and if you know the time, and have a general idea where the sun should be at that time, you can know which direction to head, navigating by the sun.

And you can often see the top of the Man visible above the dust near the ground, so you have further confirmation on direction. And much easier than knowing where the sun heading will be at what f'n time.
Sorta like navigating Central Park by looking at the sun (or cheating and noticing the buildings visible at its sides...).

[Canoe]

I guess what I should have done for the sun elevation, is indicate the descending hours. Ideally averaging the ascending & descending angles. Here it is charting the ascending angles, but indicating the descending hour pair.

I've loaded this as a transparency gif file, so you can overlay it on your shade/structure side view to see what the shade footprint will be.

[burner von braun]

Nice map Canoe. Thanks. I had a general sense of this info, but appreciate the accuracy that your map provides. Aside from the interesting solar tracking, I also noticed that 4:30 street is due south, and the prevailing wind (for what that's worth) comes in from 5:30 street. Fun little factoids to know.

[theCryptofishist]

"noon isn't vertical"
Noon isn't due South either.
I don't understand it, but I didn't have to.

Partly, it's that we're on daylight time. Or maybe it's that time zones keep brc from having its own, local noon.

[caffeineslinger]

I guess what I should have done for the sun elevation, is indicate the descending hours. Ideally averaging the ascending & descending angles. Here it is charting the ascending angles, but indicating the descending hour pair.

I've loaded this as a transparency gif file, so you can overlay it on your shade/structure side view to see what the shade footprint will be.

This is cool and useful. Thank you.

[Canoe]

Do remember that is the angle of the sun's elevation. As the azimuth/heading also changes, that angle is coming from a different direction, so a low-angle time has that sun sneaking in from the east/west, not from due South as we see at 1:00 pm. Those angles are only accurate at showing the direct shade footprint at 1pm; you have to map out the shade footprint for times materially off from 1pm.

[Canoe]

Interesting, read this in the BM blog: The city is always laid out the same way, so you’ll always see the sun coming up behind the Man as you stand in Center Camp.

Rises somewhat to the right of the Man.
Check the map.
Then the photo.
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