>I think all the global temperature records are pretty much different analyses of the same set of stations. The main independent alternative is satellite data (e.g. RSS).

So you say it is not HADCRUT or some communication problem that the number of global measurement stations has been vastly decreasing. Are you sure?
It might be that the set used for climate predictions is about the same, it actually looks like that, if I look at this list.
But like with what data are the weather predictions made?

>Meterological stations are densest in places with high populations and strong economies. They’re not necessarily located where they would be most scientifically useful.

I might miss some essential facts, but it seems to me that a simple thermometer even together with a little solar powered sender could be even under 100$. The temperature in the HadCrut file is accurate up to the tenth, so a rather cheap thermometer could be used for this.
Looking at an online market for automatic weather stations seems to substantiate
that suspicion. Setting up and reading out would need some more infrastructure and peoples work, but still -the pure technical device especially for temperature measurements seems to be easily set up and in fact it seems automated weather stations are already somewhat in use.

Moreover in densely populated aerea's where the economy is not so good one has probably enough "cheap labour" for simply reading off a cheap thermometer and meanwhile phone
coverage is pretty good also areas, which may not so be economically well off, like in parts of Africa, wikipedia writes:

>More recently, coverage has reached 90% of the territory in several countries, including Comoros, Kenya, Malawi, Mauritius, Seychelles, South Africa, and Uganda. Other countries that in 2007 reached above 50% of GSM coverage are Botswana, Burkina Faso, Burundi, Cape Verde, Guinea, Namibia, Rwanda, Senegal, Swaziland, and Togo.[2]

(but connections might be disturbed for other reasons)

Side remark: apart from temperature one could also think about measuring aerosols etc. at some such stations, like this measurement apparatus measures even methane etc.:

>Химические параметры: CO, CO2, NO2, SO2, O2, O3, H2S, NH3, AsH3, Cl2, ClO2, природный газ, С2H4O, F2, общие углеводороды,гидразин, гидриды, HCl, HCN, HF, меркаптан, метан, фосген, фосфин, и т.д.

>Метеопараметры: температура и влажность воздуха, атмосферное давление, скорость и направление ветра и т.д.

>Физические параметры: шум, радиация, электромагнитные излучения, вибрация, перемещение, освещенность и т.д.

(it though is a bit more difficult to determine the price of that, like the company just says what the price consists of but not what it is).