It’s an honest mistake, but climate and weather are not in the same bag. I could bet that you already heard a climate denier asking how could be possible the global warming theory if their citiy is so cold in winter. Spoiler: having the coldest winter in decades means nothing when we talk about climate change.
Climate is defined as the “average meteorological weather”, or as the statistical behavior of meteorological variables (temperature, wind, rain, etc.) at a given location over a long period.
According to the World Meteorological Organization (WMO), the classical period for determining climate is 30 years.
In a more simplified way, climate is the set of characteristics of a given region. For example, the Brazilian Cerrado has a well-defined climate: humid in summer and dry in winter.
Another example: Norway has a cold climate. When it comes to climate, we are not concerned with a specific day, but with a large period that accumulates the characteristics of a region.
Climate and weather difference
“Weather” is the set of atmospheric conditions and meteorological phenomena in the short term, such as temperature, rain, wind, humidity, fog, cloudiness, etc.
When you read about weather conditions in the next day or in one or two weeks, on the news, websites, or radio, you are consuming the weather forecast.
Climate, on the other hand, as explained above, deals with long periods of time and brings together the characteristics of a region. To define climate, we need the historical data of the area studied.
In short, weather refers to the meteorological conditions at the time when the observation is made.
This means that the weather may have light winds and rain in New York spring, for example, even though the state’s climate is considred ‘hot’ at this time.
Knowing that weather refers to the meteorological conditions of the moment, there are some elements that affect and are affected by these changes. Here you can find a weather elements list [and the explanation below].
- Atmospheric pressure
- Solar radiation
In low-lying places (beaches, for example), where the vertical column of air above the surface is greater, the atmospheric pressure is higher.
On the other hand, in higher areas (hills, mountains) the air column is smaller and the pressure is lower as well.
But besides altitude, air density and temperature also influence pressure – the hotter it is, the lower the air density, and the lower the pressure.
Conversely, colder regions have a higher density of air molecules and higher atmospheric pressure.
The variation in pressure is responsible for the displacement of air (wind) horizontally. The winds move from areas of higher to areas of lower pressure.
Atmospheric pressure is expressed in hectoPascals (hPa) or millibars (mb), and to measure it a device called a barometer is used.
Temperature is one of the meteorological parameters most perceptible to people, who feel cold or hot depending on various factors, such as altitude, proximity to the equator, the time of year, the acting meteorological system (cold front, warm air mass, etc.), among others.
The temperature variation at altitude is quite evident – the higher you are, the lower the temperature.
Solar radiation is the energy emitted by the Sun, which reaches the Earth in wave form. Because of the tilt of the globe, the Equator receives more radiation than the North and South Poles. This is one of the reasons why the equator is warmer than the poles.
In general, air humidity is the amount of water present in vapor form in the atmosphere. Hot places tend to be more humid, and cold regions tend to have drier climates, with some exceptions.
Wind is nothing more than air in motion. It occurs mainly due to pressure gradients, since the air tends to move from areas of higher pressure (colder) to areas of lower pressure (warmer).
There are constant winds, such as the trade winds, which blow all year round near the equator. There are also periodic or seasonal winds, such as the monsoons and coastal breezes.
Climate factors are natural features and elements that influence the climate of a particular region. The main climate factores are:
- Maritimity and continentality
- Sea currents
Check out all climate factores definition and their specifications.
Latitude is an important factor in climate. As the globe is tilted in relation to its orbit around the sun, different areas of the planet receive different amounts of solar radiation.
Thus, the closer one is to the lower latitudes (Equator), the greater the amount of radiation received and, consequently, the higher the temperature.
Latitude is, therefore, one of the factors most responsible for the existence of climate zones (tropical, temperate and polar) on the planet
The air becomes thinner and thinner as we move to higher points. And thin air means fewer particles, which decreases the air’s ability to retain heat. This is why the higher the altitude, the lower the average temperature. The reverse is also true: the lower the altitude, the higher the temperature.
Maritimity and continentality
These two terms characterize the position of a given area in relation to the sea. The greater the continentality, the farther one is from the coast and the greater the influences of this continental mass on the climate. On the other hand, the greater the maritimity, the closer one is to the sea.
This position directly interferes with the climate conditions, since the soil heats and cools much faster than the water masses. Thus, the temperature range (difference between the minimum and maximum temperature) is much greater in places where there is more continent and less ocean.
Vegetation is a factor that directly interferes and is influenced by the climate. In general, large vegetation masses tend to contain and absorb radiation more effectively, which minimizes its direct effects.
In addition, plant evapotranspiration makes these areas considerably more humid, which leads to more rainfall.
Dry regions, with little or no vegetation, such as deserts, are extremely hot, but at night they have a significant drop in temperature.
Relief is also a factor that directly influences the climate. Large obstacles, such as mountains, for example, can be factors that increase or inhibit precipitation, depending on their location and direction in relation to the regional wind.
Sea currents promote temperature variations in the oceans, and it is natural that the warmer sea has greater evaporation than the colder sea.
Greater evaporation from warmer currents generates more clouds and, consequently, more rain, which can be blown by the wind to the continent.
You may have already noticed that there are several aspects that interfere with the climate. Although the meteorological elements and climatic factors exert their influence alone, they also interact with each other. With this, a series of climatic phenomena occur, such as:
- El Niño and La Niña
- Thermal inversion
- The greenhouse effect
- Heat islands
- Acid rain
El Niño and La Niña
El Niño and La Niña are natural phenomena that occur in the Equatorial Pacific Ocean. El Niño occurs when abnormal warming of surface waters is persistent for consecutive months (above 0.5˚C) and results in a decrease in the trade winds.
As a result, the general circulation of the atmosphere changes somewhat, and the entire planet is affected.
La Niña is the opposite: the abnormal cooling of the surface waters of the Equatorial Pacific causes the trade winds to intensify and its effects are felt globally, including in Brazil.
Thermal inversion is the blocking of cold air circulation due to the presence of a layer of warm air. It occurs more frequently in more industrialized urban centers.
With this blockage, the concentration of pollutants increases and temperature changes occur.
The greenhouse effect
The greenhouse effect is a natural process that is essential for maintaining the planet’s temperature, but it is being intensified by man’s actions, mainly by burning fossil fuels, which gradually increase the planet’s average temperature.
Just like thermal inversion, heat islands are greatly influenced by human action. It consists of the rise in temperature in large urban centers, forming a kind of hot island surrounded by “colder” areas.
Naturally the rains are acidic. However, this phenomenon refers to the considerable increase in acidity caused by human action.
The burning of fossil fuels causes the increased concentration of gases such as carbon dioxide (CO2), sulfur (SO2) and sulfuric acid (H2SO4), and nitrogen oxides in the atmosphere.
These gases join with water droplets and precipitate in the form of rain, with great damage to the soil, vegetation, and aquifers.
Types of climate
With the influence of climatic factors and meteorological elements, it is possible to find different types of climate all over the world. Each has a distinctive characteristic and is influenced by its location.
There are 6 main types of climate:
The tropical climate can be observed between the Tropics of Cancer and Capricorn and presents, in most cases, low temperature variation throughout the year and a relatively high average temperature (around 20ºC).
Regarding rainfall, the volume is high, but with a tendency to decrease according to continentality. In its variations, we can find the tropical climate: rainy, monsoon, humid-dry, semi-arid and arid.
The subtropical climate is a transition zone between tropical and temperate climates. With average annual temperatures that do not exceed 18ºC, the subtropical climate has a good distribution of rain throughout the year, which marks its seasons well.
Thus, it is possible to observe, in most cases, hot and humid summers and cold and dry winters.
The equatorial climate occurs in the regions near the Equator. Because its areas of incidence receive a greater amount of solar radiation, the equatorial climate is characterized by high temperature and humidity.
In addition, the presence of equatorial forests results in great evapotranspiration and, therefore, very significant volumes of rain are observed in these locations all year round.
The temperate climate occurs between the tropics and the poles of the planet. It can be temperate oceanic (near the coast) or temperate continental (within the continental masses).
In a temperate climate, the seasons of the year are very well defined. With the exception of the interior of the continents, rainfall levels tend to be well distributed throughout the year.
The semi-arid occurs in various portions of the Earth, and is present on all continents. The semi-arid climate is marked by high temperatures and low levels of precipitation, which hardly reaches 500mm per year.
In addition, the humidity of the air is also very low, which makes these areas unable to support trees and dense vegetation.
The Mediterranean climate is more specific, and occurs near the Mediterranean Sea, in Chile, Australia, and California.
It has a hot, dry summer and a mild winter with low rainfall. Furthermore, it is very favorable for agriculture, since it is marked by the presence of trees. However, due to human action, these natural features have been practically lost.