Key Iberian Geographic & Meteorological Concepts
Key Geographic Concepts
River Basin
A watershed or drainage basin is a spatially delimited area where all surface water drains into the sea through a single river or into an endorheic lake. It is bounded by a line of summits, such as the Tagus basin.
Slope Basin
A set of rivers and their tributaries that flow into a sea, characterized by similar hydrological features. The Pacific slope is an example.
Torrent
A natural water flow located in a mountainous area with steep slopes, irregular flow, and significant erosive capacity. An example is a Pyrenean torrent near the Port de la Coughlin.
Rambla
A gully or stream with a temporary or occasional flow, characterized by steep slopes and short length, distinguishing it from rivers. An example is the Rambla de Algemesí in Valencia.
Endogenous Lakes
Lakes caused by internal Earth forces, such as tectonic or volcanic movements. These are not common in Spain; the most important is the Lagoon of La Janda (Cádiz).
Albufera
A saltwater or slightly brackish lagoon separated from the sea by a sandbar but connected to it through one or more points. It typically forms from the silting of a former bay by marine and river sediments. An example is the Albufera de Valencia.
Aquifer
A permeable stratum that allows the movement and storage of groundwater in its pores or cracks. Aquifers can consist of varied materials such as river gravel, silt, limestone, fractured sandstone, beach sands, volcanic formations, and even certain clays. The upper level of groundwater is called the water table, or phreatic surface in an unconfined aquifer. Aquifers are prevalent in Valencia.
Wetland
An area of flat land that is permanently or intermittently flooded, resulting in saturated soil, oxygen deprivation, and a hybrid ecosystem between aquatic and terrestrial environments. An example is the marshes of the United States.
Key Meteorological Concepts
Temperature Range
The temperature difference between the warmest and coldest months of the year.
Aridity
The lack of water in the soil and atmosphere, determined by the relationship between rainfall, temperature, and precipitation volume. Higher temperatures and lower precipitation increase aridity, calculated monthly and generally.
Isohyet
A line on a map connecting points with the same precipitation amount over a specific time period. Multiple isohyet maps can be created for the same area, such as average rainfall for January, February, or annual rainfall.
Azores Anticyclone
A dynamic anticyclone located in the central North Atlantic, near the Azores. It is a major weather driver for Spain and Europe, bringing dry, sunny, and hot weather during summer. It can also influence autumn, spring, and even winter, sometimes shifting its center to the Cantabrian Sea, causing dry, mild winters and blocking storms.
Action Centers
Large, slow-moving high- or low-pressure systems responsible for weather patterns in specific climate zones.
Foehn Effect
Occurs in mountainous terrain when warm, moist air is forced to rise, causing water vapor to cool and condense, forming orographic clouds and rain on the windward slopes. On the leeward side, the air descends, becoming dry and warm due to adiabatic compression, resulting in clear skies, higher temperatures, and very low humidity. This effect is observed in Puerto Cabello, Venezuela.
Front
A boundary separating two air masses with different characteristics, resulting in abrupt changes in air properties. Frontal ripples can cause storms and precipitation. A significant front for Spain enters the peninsula from the northwest (Galicia).
Gota Fría (Cold Drop)
Showers and storms of extraordinary intensity but short duration, affecting large areas, particularly in Mediterranean coastal regions, especially in September and October. These events can cause major disasters. A notable case is Gandia, Valencia, which received over 1000 mm of rain in 36 hours, with 400 mm falling in less than 6 hours.
Isotherm
A line on a map connecting points with the same temperature at a specific time. Multiple isotherm maps can be created for the same area, such as average temperatures for January, February, or annual mean temperatures. An example is the flood mapping in Santiago de Chile.