It might seem simple, but it is really complex to correctly observe the atmosphere. There are several reasons that make a meteorological observation erroneus. The most common ones are a wrong selection of the sensing element, a wrong location of the site, a drift due to age or even a wrong integration of the sensor with the data logging system. From our experience, most of the data gaps suffered by our clients are due to power failures, uneficient transmition of data systems and unefficient or non-existing maintenance programs.
Basically there are two ways of observing the atmosphere:
Advantages of such aproach are the easy to installation and operation, low drift and relatively low cost of sensors and structures.
Some disadvantages are that you need disciplined personnel in shifts to get the data every day and sampling frequency depends on frequency of visits.
Wether or not you need manual or authomatic methods is probably the first decision you will have to take in order to build your own measuring strategy that will allow you to fulfill your objectives. This and other decisions will need to be taken before designing your own network and we can help you on that.
There is not a unique solution for the same objectives, resources available are also determinant if you want to succeed. We have been doing this for years, we design, install, maintain and manage meteorological networks and we have experience with surface stations, upper air sensors, underground networks and other specific stations with very specific objectives. In order to succeed we try to follow the following steps:
- We analyze with you the resources avaible (human, technical and budget).
- You know better than nobody the objectives but we assist you in the definition at short, medium and long term.
- Together we design your mesuring strategy that will help you to succeed with your objectives. This means to decide things like the number of sites, macro and micro sitting criteria, sensors used, data logging, transmission and power.
- Finally, in order to keep the quality of the network we will define a quality assurance program that should include a corrective and preventive maintenance program and a management program. These are crucial for you to enjoy your investment during years.
Do not understimate the complexity of this process and do not hesitate to contact us. We are happy to give you some directions on it.
With the first station taking first measurements on 1998 at 2080 m height, this network was during a long time a pioneer in alpine automatic measurments. This project has been for interMET not just a project, it has been our workbench that made our human and technical skills to be taken almost to the limit.
The objective of this project was to have a rugged, compact housing for scientific quality meteorological sensors, data logging and telecommunication equipment. This housing should be easy to install and make minimum impact on the environment: no fences, no civil work and low visual impact.
Based on our experience in monitoring in alpine climates we were asked to design, install and maintain "the best" hydro-meteorological network that could be imagined in a mountain area. Considering how difficult it is to achieve reliable measurements in this environments we have proposed and installed a network base on gravimetric rain gauges, snow height sensors, 4 components radiation and specially designed sensors and systems for this environments.
We had never been asked for a meteorological station inside a cave and at the beginning it sounded easy. No vandalism, no radiation interfering the temperature probes, no animals, no rain neither rime freezing or snow. It sounded like placing a weather station in the office!. But caves are not the easiest places to work in. Special precautions regarding security must be taken due to slippery surfaces and low ceilings with threatening stalactites. From a technical point of view the difficulties come from not having sun for powering systems, no GPRS signal for communications and the worst of all: humidity always close to 99.9%. Fortunately, working together with our client we found a great and robust solution.
Met masts with mechanical anemometers and wind vanes have being the standard for wind power assessment during many years. This measuring principle relies on the conversion of the wind energy into mechanical energy that anemometers and wind vanes convert to an electric signal proportional to wind speed or wind direction. Like any other measuring technique, anemometers and wind vanes have their advantages and disadvantages. One of the limitations of anemometers and wind vanes is that that they need a solid structure to be held at a certain height, the other is that they take samples of wind almost in a single point. In the last decades, size of wind turbines have grown considerably. With this increment on rotor height, a more precise assessment of the wind profile is then necessary in order to make a better production forecasting. It is possible to use tall towers with sensors all their way up to 100 meters or more, but the increase of the costs of such towers increase considerably. This fact along with others like reliability, installation and maintenance costs and environmental impact make necessary to consider other measurement techniques that do not need towers. One option is to use a SODAR (SOund Detection And Ranging). They use the heterogeneities found on air to reflect ultrasonic sound pulses and retrieve their velocity using the Doppler effect theory. SODARs are at ground level but can reach very high levels of the atmosphere, depending on their configuration. SODARs specially focused on the first hundreds of meters of the atmosphere have become in the last years very helpful on the wind energy resource area.
Our meteorological networks ussually have had spring, winter and fall as the “hot” season since it is when most interesting meteorological phenomena ocurrs at midle latitudes. Mostly of our skills and experience was earned to deal with winter related technical problems. For this network, it was the opposite. Wild fire risk is higher in late spring, summer and early fall, so concentration needs to be kept high all the year round.