Meteorology, the science that studies the atmosphere, its properties and the phenomena that take place in it, has gained considerable importance in recent years. In fact, weather forecasts determine important productive sectors such as agriculture and tourism.
Meteorological sensors, interpretation of atmospheric signals
A meteorological sensor, as defined by the National Meteorological Agency (AEMET), is “a device designed to receive information of a meteorological nature and to convert it into another, often electrical, form that can be quantified and processed to facilitate its understanding”. When several of these sensors are grouped together in a single installation, they are referred to as meteorological stations, which in turn can form more or less extensive meteorological observation networks with different purposes and resolutions.
The observation of these phenomena over time, the study of their averages and their extremes, lead to the definition of the climate of an area. In other words, the climate is a synthesis of the meteorological phenomena that can be expected in any place at any time.
What are the most commonly used meteorological sensors?
In the field of meteorology, the continuous monitoring of variables such as
- Air temperature
- Atmospheric pressure
- Wind speed and direction
- Solar radiation
- Atmospheric humidity
Temperature, the thermal sensation interpreted in numbers
The measurement of temperature is one of the best known and most widely used quantities. It is a physical quantity, measured by a sensor, that allows us to know the thermal energy or heat quantity of a body, object or environment and its variations.
There are different types of sensors used to monitor temperature:
- Thermocouple sensors, one of the most widely used due to its quality/price ratio.
- RTD sensors, which offer high accuracy.
- Thermistor sensors, which detect the change in temperature by the change in resistance of a semiconductor.
- Thermometers, which measure the response of the mercury or alcohol inside to heat.
Atmospheric pressure, calculating the weight of air
Atmospheric pressure measures the force exerted by air on a body or surface as a result of gravity.
It is usually measured by a barometer (mercury, aneroid, etc.) and its calculation is influenced by several variables such as altitude, temperature or humidity.
Wind, monitoring the behaviour of air in motion
Wind is defined as the movement of air between two points of different pressure or temperature. The main aspects considered are
- Direction, to determine which way the wind is blowing.
- Speed, which is usually measured with an anemometer, an instrument made up of cups that define this parameter based on the speed of rotation.
Solar radiation, the energy emitted by the sun
Solar radiation is a measure of the electromagnetic energy transmitted from the Sun to the Earth’s surface.
It is calculated using instruments called pyranometers, also known as solarimeters or actinometers, which measure solar radiation in kilowatts per square metre over a 180-degree field. Solar radiation can also be estimated using a heliograph, an instrument that measures hours of sunshine.
Humidity, how much water vapour is in the air?
Humidity is defined as the amount of water vapour in the air.
There are several ways to refer to this variable (absolute humidity, specific humidity, etc.), but one of the most common measurements is relative humidity. It is monitored using a psychrometer, a type of hygrometer that is more accurate than those used in the home.
Precipitation, the water that accompanies clouds
Precipitation is the fall of water from the atmosphere to the Earth’s surface. It is a phenomenon that can take the form of rain, snow or hail.
The instrument used to measure it is the rain gauge, which basically consists of a funnel that collects the water and directs it to a graduated vessel that measures the amount of precipitation that has fallen at a given place and time.
What are weather sensors used for?
Weather forecasts are crucial for sectors such as agriculture and tourism. In fact, phenomena such as climate change, which introduces a great deal of uncertainty by altering normal weather patterns, make hyper-local forecasts particularly valuable for decision making.
In the case of agriculture, for example, in monsoon countries, weather forecasts make it easier to decide which crops to plant or how much land to prepare for cultivation. In other latitudes, detailed weather forecasts can help minimise losses due to storms or late frosts.
Tourism is also heavily dependent on weather forecasts, as it is a variable that influences hotel bookings or the organisation of outdoor events.
But there are also other applications.
- Air quality monitoring: Pollutant emissions undergo a transformation in the atmosphere that defines immission levels, a transformation in which meteorological variables play an important role, which is why air quality stations such as those installed by ENVIRA incorporate meteorological sensors.
- Renewable energy production: the existence of resources such as wind or sun is essential for the production of renewable energy, so having data on solar radiation, for example, can help to increase the performance of photovoltaic installations.
- Weather monitoring for drone operations: The flight plans required for drone operations must take into account weather conditions.
- Road Weather Information System (RWIS): These systems are particularly useful during the winter season, providing information to improve road safety and data for modelling.
In short, meteorological sensors help to reduce the uncertainty caused by meteorology.
The monitoring solutions offered by ENVIRA incorporate the latest technologies available on the market and are characterised by their reliability, providing local information to support decision making. Detailed data reduces risks in agricultural activities, improves the performance of renewable energy installations or makes road travel safer, all in the context of a climate crisis in which the weather seems to have gone mad.