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1. ABSTRACT:
A weather station is a facility, either on land or sea, with instruments and equipment for measuring atmospheric conditions to provide information for weather forecasts and to study the weather and climate. The measurements taken include temperature, atmospheric pressure, humidity, wind speed, wind direction, and precipitation amounts. Wind measurements are taken with as few other obstructions as possible, while temperature and humidity measurements are kept free from direct solar radiation, or insulation. Here in the 21st century, you can create your own backyard weather station that is computer-controlled, where all of the data is automatically captured and stored for later analysis. No littler black log book. In this project, we will be making a weather station that measures air pressure, temperature, rain drop, and air humidity using Arduino which save the data for data acquisition.
This weather station can be so much helpful for farmers after it is made portable, wireless, and user friendly. Their fields are usually far away from their residence. This makes it difficult for them to reach the field on time when there is any storm or heavy rain. This weather station can be placed at their farm and can be connected to their PCs through a wire which helps them to monitor their farm from their home.
2. INTRODUCTION:
2.1 What Is A Weather Station?
A weather station is a facility, either on land or sea, with instruments and equipment for measuring atmospheric conditions to provide information for weather forecasts and to study the weather and climate. The measurements taken include temperature, atmospheric pressure, humidity, wind speed, wind direction, and precipitation amounts. Wind measurements are taken with as few other obstructions as possible, while temperature and humidity measurements are kept free from direct solar radiation, or insulation. Manual observations are taken at least once daily, while automated measurements are taken at least once an hour. Weather conditions out at sea are taken
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Figure 1: Weather station by ships and buoys, which measure slightly different meteorological quantities such as sea surface temperature (SST), wave height, and wave period. Drifting buoys outnumber their moored versions by a significant amount.
2.2 General Instruments and Their Exposure
• Thermometer for measuring air and sea surface temperature
• Barometer for measuring atmospheric pressure
• Hygrometer for measuring humidity
• Anemometer for measuring wind speed
• Pyranometer for measuring solar radiation
• Rain gauge for measuring liquid precipitation over a set period of time.
In addition, at certain automated airport weather stations, additional instruments may be employed, including:
• Present Weather/Precipitation Identification Sensor for identifying falling precipitation
• Disdrometer for measuring drop size distribution
• Transmissometer for measuring visibility
• Ceilometer for measuring cloud ceiling
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More sophisticated stations may also measure the ultraviolet index, leaf wetness, soil moisture, soil temperature, water temperature in ponds, lakes, creeks, or rivers, and occasionally other data.
Except for those instruments requiring direct exposure to the elements (anemometer, rain gauge), the instruments should be sheltered in a vented box, usually a Stevenson screen, to keep direct sunlight off the thermometer and wind off the hygrometer. The instrumentation may be specialized to allow for periodic recording otherwise significant manual labour is required for record keeping. Automatic transmission of data, in a format such as METAR, is also desirable as many weather stations’ data is required for weather forecasting.
2.3 Types of Weather Stations
Personal weather station: A personal weather station is a set of weather measuring instruments operated by a private individual, club, association, or even business (where obtaining and distributing weather data is not a part of the entity’s business operation). Personal weather stations have become more advanced and can include many different sensors to measure weather conditions. These sensors can vary between models but most measure wind speed, wind direction, outdoor and indoor temperatures, outdoor and indoor humidity, barometric pressure, rainfall, and finally UV or solar radiation. Other sensors that may be available can measure soil moisture, soil temperature, and leaf wetness. The quality, number of instruments, and placement of personal weather stations can vary widely, making the determination of which stations collect accurate, meaningful, and comparable data difficult. Dedicated ships: A weather ship was a ship stationed in the ocean as a platform for surface and upper air meteorological measurements for use in weather forecasting. It was also meant to aid in search and rescue operations and to support transatlantic flights. The establishment of weather ships proved to be so useful during World War II that the International Civil Aviation Organization (ICAO) established a global network of 13 weather ships in 1948. Of the 12 left in operation in 1996, nine were located in the northern Atlantic Ocean while three were located in the northern Pacific Ocean. The agreement of the weather ships ended in 1990. Weather ship observations proved to be helpful in wind and wave studies, as they did not avoid weather systems like merchant ships tended to and were considered a valuable resource. The last weather ship was MS Polarfront, known as weather station M (“jilindras”) at 66°N, 02°E, run by the Norwegian Meteorological Institute. MS Polarfront was removed from service January 1, 2010. Since the 1960s this role has been largely superseded by satellites, long range aircraft and weather buoys. Weather observations from ships continue from thousands
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Figure 2: Weather Ship of voluntary merchant vessels in routine commercial operation; the Old Weather crowd sourcing project transcribes naval logs from before the era of dedicated ships.
Dedicated buoys: Weather buoys are instruments which collect weather and oceanography data within the world’s oceans and lakes. Moored buoys have been in use since 1951, while drifting buoys have been used since the late 1970s. Moored buoys are connected with the seabed using either chains, nylon, or buoyant polypropylene. With the decline of the weather ship, they have taken a more primary role in measuring conditions over the open seas since the 1970s. During the 1980s and 1990s, a network of buoys in the central and eastern tropical Pacific ocean helped study the El Niño-Southern Oscillation. Moored weather buoys range from 1.5 metres (4.9 ft) to 12 metres (39 ft) in diameter, while drifting buoys are smaller, with diameters of 30 centimetres (12 in) to 40 centimetres (16 in). Drifting buoys are the dominant form of weather buoy in sheer number, with 1250 located worldwide. Wind data from buoys has smaller error than that from ships. There are differences in the values of sea surface temperature measurements between the two platforms as well, relating to the depth of the measurement and whether or not the water is heated by the ship which measures the quantity. Synoptic weather station:Synoptic weather stations are instruments which collect meteorological information at synoptic time 00h00, 06h00, 12h00, 18h00 (UTC) and at intermediate synoptic hours 03h00, 09h00, 15h00, 21h00 (UTC). The common instruments of measure are anemometer, wind vane, pressure sensor, thermometer, hygrometer, and rain gauge.
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Figure 3: Weather station in Farm The weather measures are formatted in special format and transmit to WMO to help the weather forecast model. 3. COMPONENTS REQUIRED • Arduino, e.g. Arduino Uno • DHT11 Humidity and temperature sensor • BMP180 Barometer • Rain Drop sensor module • Universal PCB Boards • Enclosure of your choice • Personal computer with installed Arduino libraries • USB Type A Male to Type B Male
4. COMPONENTS DESCRIPTION
4.1 Arduino: Arduino is a prototype platform (open-source) based on an easy-to-use hardware and software. It consists of a circuit board, which can be programed (referred to as a microcontroller) and a ready-made software called Arduino IDE (Integrated Development Environment), which is used to write and upload the computer code to the physical board.
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The key features are ?
Arduino boards are able to read analog or digital input signals from different sensors and turn it into an output such as activating a motor, turning LED on/off, connect to the cloud and many other actions.You can control your board functions by sending a set of instructions to the microcontroller on the board via Arduino IDE (referred to as uploading software).
Unlike most previous programmable circuit boards, Arduino does not need an extra piece of hardware (called a programmer) in order to load a new code onto the board. You can simply use a USB cable.
Additionally, the Arduino IDE uses a simplified version of C++, making it easier to learn to program.
Finally, Arduino provides a standard form factor that breaks the functions of the micro-controller into a more accessible package.
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Figure 4: Arduino Pin Diagram
4.2 DHT11Temperature and Humidity sensor DHT11 is a part of DHTXX series of Humidity sensors. The other sensor in this series is DHT22. Both these sensors are Relative Humidity (RH) Sensor. As a result, they will measure both the humidity and temperature. Although DHT11 Humidity Sensors are cheap and slow, they are very popular among hobbyists and beginners.
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The DHT11 Humidity and Temperature Sensor consists of 3 main components. A resistive type humidity sensor, an NTC (negative temperature coefficient) thermistor (to measure the temperature) and an 8-bit microcontroller, which converts the analog signals from both the sensors and sends out single digital signal.This digital signal can be read by any microcontroller or microprocessor for further analysis. Figure 5: DHT11 DHT11 Humidity Sensor consists of 4 pins: VCC, Data Out, Not Connected (NC) and GND. The range of voltage for VCC pin is 3.5V to 5.5V. A 5V supply would do fine. The data from the Data Out pin is a serial digital data.
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