How to check water temperature a little less than 1 mile away?

Question

Hi,

I was wondering if anyone has any experience in this type of thing (basically weather monitoring) and could point me in the right direction.

If you go in a straight line, I live 0.88 miles (less than 1) from a beach. I would like to monitor the water temperature remotely. I can't run any wires to my house (it's almost a mile, and not my property) and basic weather units from Oregon Scientific and the like do not broadcast a signal that far away.

Does anyone know of any way I can do this? I would need a waterproof, water temperature sensor, some device/way of broadcasting the signal to my house, and something in my house to be able to check the temperature.

I also would need a power source for the sensor, but I'm ok with a long-term battery or even using some type of solar/wind power solution.

Do products exist that would make this possible?

Thanks so much for your help.

Answer 1

Yes there are products on the market that will do exactly what you want.See link below for an example. I do think a cheaper way would be to have a data logger that would record the temperature ever hour or whatever time interval you want and you can collect the recorded data the next time you visit the site.

Answer 2

Depending on where you are, you can hire me to live near the beach and I will happily take manual readings and phone them in to you daily.

:)

Actually what you need is a wireless, submersible sensor, and then a series of repeaters. These take the signal, re-amplify it and then pass it along to another repeater, or the end-receiver where you can then monitor it on your computer.

Don't know how applicable the site I gave you will be for you. Depends on the terrain and ambient conditions, but it's one possibility for you.

So, in theory it should be doable. Hope this helps.

***** If I'm not mistaken, IR Pyrometry is a way of taking thermal readings by bouncing a signal off the source. They do this with extreme conditions like in glass and steel plants, but for your purposes you would not get the accuracy you'd probably need. If you can't use repeaters, then your options dwindle, unfortunately.

Hmmmmmmmm....seems this should be a solvable problem.

Answer 3

Infra red pyrometry or camera! It would only measure the surface temperature of course but could be used more flexibly than a fixed sensor.All power needs would be 'inhouse'but I dont know how you would record,maybe snapshots stored on you PC?

Answer 4

You're likely not going to find a consumer system that can do that.  Anything that transmits that far via radio will need FCC licensing and so forth.  

You don't say what the beach looks like, if there is public access, a pier, power, or how urban it is, and probably most important how secure you can make your instrumentation.  That infrastructure is going to be key for how you do this.  If there is broadband internet and power you can use, you might be able to set up a Wi-Fi data system that logs temperature and then posts it to a website.  Davis Instruments makes something like this (I think), although I don't think they have a small stand-alone package that will do it all and you would need a remote computer (you also have to do some hacking with a soldering iron to get a Davis monitor to record water temperature (although it can be done and is not complicated)).  You might also be able to use a modem and a cell-phone with a Davis-type system.  

Keep in mind that minimizing vandalism in any remote data logging system is critical for long-term operation.  

Finally, you ought to snoop around on the internet and see if someone is already logging temperature nearby.  There are lots of local marine/meteorological observatories and someone may have one running close enough for you to use.

edit:  the FCC power limit is 0.5 W, which translates to a clear-ground range of 2 miles.  In practice, with buildings and trees and such, your range will be less so you would be pushing it at a mile through a populated area.  Whether of not a consumer "walkie-talkie" based system exists that can be used for data transmission is another issue.  I've never seen such a thing.  Omega Engineering or Davis Instruments both have much more restricted range on their wireless systems (leaving me to believe that the smaller range is either technologically or regulatory related).  Anyway, the bigger issue is probably site security.  You would not believe the vandalism that goes on at remote data stations.  The TAO buoys moored out in the middle of the Pacific Ocean routinely get stripped of sensors.  

You might give Omega a phone call and see what they recommend.  I only glanced at their wireless stuff.

edit2:  One last thing, infrared pyrometry isn't really an option at a distance of a mile.  The reasons why are related to the Fresnel coefficients at what is essentially a grazing angle of zero and the infrared emissivity of water.  So an infrared sensor would have to be mounted near the water and then you would have the same issues with data transmission.