Confusing weather and climate can lead to erroneous conclusions. For example, an unusually cold week in a warm region is a weather event. If that cold trend persists and becomes established over decades, then we could be talking about a change in climate. All of this is recorded in precise and detailed meteorological statistics to ensure we don't fall victim to climate amnesia. In other words, weather is the current mood, while climate is the region's personality.
What is weather? It's the state of the atmosphere, what can be seen through a window with the naked eye, at a given time and in a specific location. It is measured over short periods of hours, days, or, at most, a week, and can be accurately predicted using scientific tools through the discipline of meteorology, which combines physics, mathematics, and applied computer science. Its key elements are temperature, humidity, cloud cover, precipitation (rain, hail, snow, etc.), and wind.
What about climate? This is the statistically average weather conditions over a long period of time, generally 30 years or more. It is a region's "personality" in terms of temperature, precipitation, humidity, etc. In other words, it's the conditions that can be typically expected at a given latitude depending on the season and the region's position relative to the Earth's axis, according to the World Meteorological Organization (WMO). In this case, it is determined by latitude, altitude, distance from the sea, and ocean currents.
Of all these factors, latitude has the greatest influence. The Earth doesn't receive the Sun's energy evenly due to a combination of two factors: the planet's spherical shape and the tilt of its axis. Latitude is the distance of a point on Earth from the equator, the imaginary line that encircles it. Depending on how the sun's rays hit the Earth, the planet is divided into three major climate zones:
- Warm or tropical zone: located between the Tropic of Cancer and the Tropic of Capricorn. Here, the sun's rays strike the earth perpendicularly throughout the year, resulting in consistently high temperatures.
- Temperate zone: this is the region located between the tropics and the polar circles, such as Europe. The sun's rays strike the Earth at a more oblique angle. This region is characterized by distinct seasons as the Earth's axial tilt causes solar exposure to vary significantly every four months. During the Earth's orbital motion, this tilt of the Earth's axis causes one of the hemispheres to be more exposed to the Sun. This means that it's summer in the Northern Hemisphere while the Southern Hemisphere is going through winter, and vice versa.
- Cold or polar zone: near the polar circles. Sunlight hits the Earth's surface at a very low angle and is scattered over a larger area, providing very little warmth despite the exceptional natural phenomenon known as the Midnight Sun, where the sun remains above the horizon 24 hours a day in the Arctic between approximately May 21 and July 22 during the European summer and does the same in the Antarctic during summer in the Southern Hemisphere.
Although weather — the specific conditions at a given time and place — and climate — the long-term statistical pattern that defines a region — are often confused, understanding this difference is important and is linked to the definition of the Sustainable Development Goals (SDGs).
It was precisely when we came to understand that climate change was not a temporary phenomenon but a structural issue in the context of current conditions that an international consensus emerged to protect our finite natural resources.
Understanding the difference between these two concepts not only helps us better interpret what is happening around us but also gives us a long-term perspective. It is in these patterns that we can find major challenges, as well as opportunities, for moving forward toward a more sustainable balance.