::: Weather Station

The weather station is located in the west periphery of Pisa (Tuscany - Italy - 4 m amsl) and it may be classified as an urban weather station.

It is a semi-professional weather station (Davis Vantage Pro 2 model) with temperature sensor, humidity, atmospheric pressure, precipitation, wind speed and direction. They are properly placed outdoor so to respect the World Meteorological Organization (WMO) guidelines. Thus weather data recording is as much as possible objective and data can be compared with data of other weather stations.

The thermo-hygrometer is placed in front of a balcony and a bar keeps it away about 3 m from the wall of the house so to reduce heat and radiative exchange between sensors and exterior wall. It is about at an elevation of 5 m above the ground and is placed in south direction relative to the house. Both thermometer and hygrometer are protected from a solar powered fan aspirated radiation shield and are illuminated many hours a day the whole year long.

The rain gauge is placed on the roof at an elevation of 10 m above the ground, distant from exterior house walls, trees and any other obstacle, so it can collect all of the rain which falls from the sky. It has a 0.2 mm resolution and stores data every 10 seconds. The rain gauge is placed on the east side of the roof, so it is more protected against the strong and common southwest winds.

The anemometer is placed on the roof at an elevation of 12 m above the ground. There are not any obstacles in each direction, thus wind speed and direction measurements are not affected by abnormal local turbulence phenomena. The lowest measurable gust speed is about 0.4 m/s and each value is stored every 2.5 seconds.

Barometer is ensconced inside the house because pressure changes locally depend only on elevation. It has a 0.1 hPa resolution.

All of the sensors are alimented by a solar cell (also equipped with sandard batteries) and signals are transmitted via radio to a console placed indoor. It shows data received on the screen and transmits them to a small network device (ALIX1.D). It works as a datalogger because it stores all of the data received, furthermore it is able to send data and graphs to my own website through an Internet connection. Essentially it is a small pc with low energy consumption (passive ventilation) which is connected both to the weather station and to the network through the router and with a dedicated software (Meteohub) for meteorological data management. It may be reached and configured directly through a browser via http, too.

Since Meteohub gets current data recorded by sensors, it immediately and constantly sends them to the website where they are managed from Weather Display Live software. It immediately shows data through an animated display and so it allows a real time visualization of current meteorological conditions. Any other tables and graphs displayed in the website's pages are updated less frequently; update time interval depends on the type of information which is displayed.

The Data archive is made by a software (AMEC) I have created using both Excel and Matlab programs. It automatically analyzes all of the data stored into the datalogger and creates compacted and simple files with a lot of statistics and graphs.

A second weather station is also installed (Oregon Scientific WMR928NX). It stores temperature, humidity and precipitation data, but these informations are neither available on the website, nor stored into archives.