Author Topic: Solar Radiation Shield for Fine Offset - Works Pretty Well  (Read 556 times)

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Offline Farmtalk

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I've had an Ambient WS-1090 fine offset station running for about the last four months now. Recently, I was noticing that I was receiving my high temperature reports around 5:30 p.m., which seemed a little late to me considering my latitude (about 38 degrees N). I started checking the station graphs by day and was noticing about a five - seven degree spike in temperature during that time frame because the sun was hitting it.

The WS-1090 to me is a nice station for the price - no Davis or any flagship - but a good starter. But one thing it does lack is much of a solar radiation shield. I mean it's as thin as an eggshell practically, and I knew then and there that I was going to have to do something.

I work at a news station as the morning producer, so the money isn't great to where I could build or buy a Stevenson screen, but I did see that Ambient sells their own add-on solar radiation shield. So I gave it a shot.

This shield is huge! It is about the size of a basketball, and the sensor itself is about the size of a thermos, so you can imagine the surprise when I saw how big it was. After assembling it and attaching to my pole, I have given it a few days to see if it improved the data accuracy any, and I can say for sure that it does.

Now, I see usually no more than a degree increase as a result of sun, which for this station is doing pretty well. Eventually, I'll move up the ranks to a Davis or perhaps something else, but times are different for now.  8-)

So if there is anybody using a fine offset out there with a similar issue, I would say the solar shield is definitely worth the $40 tag.  8-)
Weather Software-> GREarth, GRAnalyst 2.xx, MRLevel3, GRLevel 3 2.xx, Bufkit, GRLevel2, WXSim, and Radarscope.
Weather Station-> Ambient Weather WS-1090 Fine Offset
Weather Station Software-> Weather Display 10.37S, Cumulus 1.94
CoCoRaHS ID->  WV-KN-27
Administrator-> www.fitzweather.org

Offline wxtech

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Re: Solar Radiation Shield for Fine Offset - Works Pretty Well
« Reply #1 on: May 17, 2018, 09:03:46 PM »
Very interesting station.  I have a problem with trees shading the sensor early morning with low sun.  Couldn't fix it.  I have the Ambient shield also, no longer used.  I have some smaller shields packed away somewhere.
Impressed that you capture the daily CoCoRaHS county rainfall map for your site.  How do you do that?  Is it automated/software?  I have a Davis VP2+, old, fungi covered, needs refurbishing.  Ambient is my favorite equipment source. 
Since you're working at a news job, see if NWS will outfit you with a CoOp station.  Free eqpt installation.  You would be good publicity for NWS.
Al Washington, Lexington, Ga.,  NWS Coop station=LXTG1, Fischer Porter, SRG, MMTS. 
CoCoRaHS=GA-OG-1. CWOP=CW2074.  Davis VP2+ WLIP 5.9.2, VP(original) serial, VWS v15.00 p02. ImageSalsa, Win7 & Win8 all-in-one.

Offline Farmtalk

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Re: Solar Radiation Shield for Fine Offset - Works Pretty Well
« Reply #2 on: May 18, 2018, 03:09:49 AM »
Very interesting station.  I have a problem with trees shading the sensor early morning with low sun.  Couldn't fix it.  I have the Ambient shield also, no longer used.  I have some smaller shields packed away somewhere.
Impressed that you capture the daily CoCoRaHS county rainfall map for your site.  How do you do that?  Is it automated/software?  I have a Davis VP2+, old, fungi covered, needs refurbishing.  Ambient is my favorite equipment source. 
Since you're working at a news job, see if NWS will outfit you with a CoOp station.  Free eqpt installation.  You would be good publicity for NWS.

If you have any shields you are not using that might fit right around the sensor itself that would fit inside the big shield, let me know.  :-)

Impressed that you capture the daily CoCoRaHS county rainfall map for your site.  How do you do that?  Is it automated/software?

Are you talking about this page? http://fitzweather.org/wxcocorahs.php

I can send the file if you wish - I found it here on the forum. The only thing that sometimes does not work for me with it is that I get up REALLY early for work (between 1:30 a.m. and 2:30 a.m.), and I measure my CoCoRaHS measurements at 3 a.m. The company seems to like the uniform 7 a.m. time and my measurements sometimes do not show up in the script as a result.

It isn't the script because other county reports show up for the day, just not mine. But I do not really have a choice on the matter right now.

Since you're working at a news job, see if NWS will outfit you with a CoOp station.  Free eqpt installation.  You would be good publicity for NWS.

That's a great idea.  8-)
Weather Software-> GREarth, GRAnalyst 2.xx, MRLevel3, GRLevel 3 2.xx, Bufkit, GRLevel2, WXSim, and Radarscope.
Weather Station-> Ambient Weather WS-1090 Fine Offset
Weather Station Software-> Weather Display 10.37S, Cumulus 1.94
CoCoRaHS ID->  WV-KN-27
Administrator-> www.fitzweather.org

Offline wxtech

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Re: Solar Radiation Shield for Fine Offset - Works Pretty Well
« Reply #3 on: May 18, 2018, 07:56:19 AM »
The attached photo compares the 2 shields. [ You are not allowed to view attachments ]
It is too big to fit inside the Ambient shield.
Al Washington, Lexington, Ga.,  NWS Coop station=LXTG1, Fischer Porter, SRG, MMTS. 
CoCoRaHS=GA-OG-1. CWOP=CW2074.  Davis VP2+ WLIP 5.9.2, VP(original) serial, VWS v15.00 p02. ImageSalsa, Win7 & Win8 all-in-one.

Offline Farmtalk

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Re: Solar Radiation Shield for Fine Offset - Works Pretty Well
« Reply #4 on: May 18, 2018, 09:48:35 AM »
That shield is huge!  8-)

I think the larger shield would certainly take care of any radiation issues!

I use just a simple 8 feet metal pipe to brace everything off of, but eventually, I would like to use a more sturdy tower structure to keep things level. I am surprised how just being off a little from being plumb level affects wind measurements I suppose due to the slight angle.
Weather Software-> GREarth, GRAnalyst 2.xx, MRLevel3, GRLevel 3 2.xx, Bufkit, GRLevel2, WXSim, and Radarscope.
Weather Station-> Ambient Weather WS-1090 Fine Offset
Weather Station Software-> Weather Display 10.37S, Cumulus 1.94
CoCoRaHS ID->  WV-KN-27
Administrator-> www.fitzweather.org

 

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