Essential Weather & Climate Terminology

Posted on Sep 26, 2025 in Geology

Understanding Weather and Climate Basics

Weather:: The state of the atmosphere of a place at a particular time. It is characterized by its variability, but determined by direct observations.
Meteorology:: The science of weather.
Climate:: The average state of the atmosphere of a place. This state is caused by the usual succession of weather types at a location throughout the year.
Climatology:: The science of climate.

Solana:: It refers to the sunny slopes of a mountain or mountainous area that generally receive more solar radiation, compared to the slopes or hillsides of Umbría.
Umbría:: Hillsides or mountain slopes that are oriented away from the sun, i.e., in the rain shadow zone.
Latitude:: The angular distance between the Equator and a certain point on the planet, measured along the meridian passing through that point.
Longitude:: Expresses the angular distance between a given point on the Earth’s surface and the meridian taken as 0°, usually the Greenwich Meridian.
Windward:: The direction from which the wind blows at a specific time and place.
Leeward:: The direction towards which the wind blows at a specific time and place, i.e., a meaning consistent with the wind’s flow.
Tropopause:: Sets the upper limit of the troposphere, above which the temperature remains constant before increasing again at about 20 km.
Jet Stream:: Rapid, relatively narrow air currents found in the atmosphere at an altitude of about 11 kilometers above the Earth’s surface and below the tropopause.

Barometer:: An instrument that measures the pressure exerted by atmospheric air at any point in the atmosphere.
Isobar:: A line of equal or constant pressure on a graph or map. Except for special cases, isobars connect points of equal atmospheric pressure on a map.
Anticyclone:: An area of high atmospheric pressure, where the pressure is higher than the surrounding air.
Cyclone / Depression:: A region where the atmospheric pressure is lower than the surrounding air.
Occluded Front:: This occurs when a faster-moving cold front overtakes a slower-moving warm front. The cold front wedges beneath the warm front, lifting it.

Insolation / Solar Radiation:: The amount of solar radiation received by the Earth’s surface.
Clouds:: Visible masses of water droplets or ice crystals suspended in the atmosphere, often resulting in an overcast sky to varying degrees.
Isotherm:: A line on a map connecting points that have the same temperature at a given time or over a specific period.
Temperature Range:: The difference between the highest and lowest temperatures recorded in a place or area over a specific period.
Advection:: The horizontal transport of atmospheric properties, such as heat or moisture, by the wind.
Calima / Haze:: The presence of very small particles of dust and sand suspended in the atmosphere, often reducing visibility.
Relative Humidity:: The ratio of the amount of water vapor in the air to the maximum amount of water vapor the air can hold at a given temperature, expressed as a percentage.

Isohyet:: A line on a map connecting points that receive the same amount of precipitation over a given period.
Orographic Precipitation:: Precipitation produced when a plume of humid air rises as it encounters an orographic obstacle (e.g., a mountain), cools, and condenses.
Convection:: One of the three forms of heat transfer, characterized by the movement of a fluid (liquid or gas) that transports heat between zones of different temperatures.
Evapotranspiration:: The combined process of water loss from a surface by direct evaporation and water loss by transpiration from vegetation.
Aridity:: The lack of water in the soil and moisture in the air that is in contact with it.
Gauss Aridity Index:: An index used in climatology to determine periods of aridity.
Meyer-Lautensach Aridity Index:: Determines the general aridity of an area based on the number of months with a water deficit.