Do you know the difference between heat and temperature? These two concepts are often confused and misused. While closely related, they are not identical. Heat is a form of energy, while temperature is the quality that determines the direction of heat flow.
But what are the characteristics of each one? We'll discuss this and much more in this special article.
What exactly is heat?
On sunny days, and especially in summer, the expression we most often say is: "It's so hot!", right? Well, this sensation is caused by the sun, which is a much larger object than the planet Earth (it has a diameter of 696.000 km, while our home 'only' measures 6.371 km), and much hotter: about 5600ºC , compared to the average of 14ºC recorded here.
Heat can be described as a transfer of energy from an object at a higher temperature to one that is 'colder'. Thus, the two objects reach thermal equilibrium, which is what happens, for example, when we get into bed in winter: the sheets and blankets are cold at first, but gradually warm up.
Heat energy can be transferred in three different ways:
Radiation: when it propagates in the form of electromagnetic waves, such as solar energy.
Driving: when it spreads by direct contact, such as when we put a spoon in fresh coffee.
Convection: when it is propagated by means of a liquid or gas, like the heaters we have at home.
And, once this happens, the object can change to a different state , which can be solid, liquid, or gas. These changes are known as phase changes, which continuously shape Earth's natural world. The most frequent phase changes in meteorology are:
From solid to liquid, called fusion.
From liquid to solid, called solidification.
From liquid to gaseous, called vaporization.
From gaseous to liquid, called condensation.
Heat energy is measured in calories , unlike temperature which is measured in degrees (whether Kelvin, Celsius or Fahrenheit), or also in Joules (1 joule is equivalent to approximately 0,23 calories).
Definition of temperature
Temperature is a property of matter that is measured with a thermometer . The closer an object is to another, hotter object, the higher its temperature will rise. For example, when we are sick and have a fever, our body temperature also increases.
There are three scales that measure it, as we have mentioned before:
Celsius: the one we know and use the most in Europe, whose reference points are freezing (0ºC) and boiling (100ºC).
Fahrenheit: it is used especially in Anglo-Saxon countries. Its reference points are the freezing of an antifreeze mixture of water and salt, and the temperature of the human body. 1ºC equals 33,8ºF.
Kelvin: for scientific use. Its reference points are absolute zero and the triple point of water. 1ºC is equivalent to 274,15ºK.
Temperatures on Earth
Temperature varies with altitude, proximity to the sea and the equator, topography, and also the flora itself (the more forested areas there are, the more water vapor these plants generate through photosynthesis, which can help us cope better with the heat). Broadly speaking, the planet can be divided into three main zones:
Warm or tropical zone: located between the two tropics and divided by the equator into two equal zones. The average temperature is above 18ºC.
Temperate zone (north and south): they extend from the tropics to the poles. The annual average temperatures remain around 15ºC. In regions located in the temperate zone, the seasons of the year are well defined.
Cold zone (the poles): located between the Arctic Circle and the North Pole, and the Antarctic Polar Circle and the South Pole. Temperatures are practically always kept below 0ºC, even reaching -89ºC.
And the thermal sensation?
Even if the thermometer shows a certain temperature in our area, our body might feel something different, which is when we talk about the wind chill . What exactly is it?
The perceived temperature is the body's reaction to the ambient temperature , and the perceived temperature is when it exceeds 26ºC, although it varies considerably depending on the season and the individual. For this reason, those who live in temperate or cold climates don't usually enjoy the humid heat of the Mediterranean, while those who live in tropical or subtropical climates often find it difficult to adapt to a cold climate.
The higher the humidity, the hotter it will feel; and the lower the humidity, the colder it will feel. So, for example, a temperature of 30ºC with 90% humidity will feel like 40ºC.
Did you know the relationship between heat and temperature?
