Iberian Peninsula: Factors Influencing Climate
Factors Influencing the Iberian Peninsula’s Climate
Geography:
Latitude: The Iberian Peninsula is located in the temperate zone, which results in two clearly marked seasons and two transitional seasons. Its position in southwestern Europe means it is affected by the zonal circulation of the West.
Maritime Influence: The location between two seas influences temperature regulation, helping to create mild climates with lower temperature ranges. The Mediterranean Sea has higher temperatures than the Atlantic, but its effect on the interior is less pronounced.
Proximity to Africa: This brings continental air masses and dry conditions.
Relief: The peripheral relief, except in the west, makes it difficult for moist air masses to penetrate. The coastline’s shape also limits air intake, contributing to differences between the interior and coastal regions.
Altitude: Approximately 20% of Spanish territory is over 1000 meters. This altitude gives rise to the foehn effect (a temperature decrease of -0.6°C for every 100 meters of elevation gain).
Continental Character: This character arises because the continental plateau climate creates contrasts between the interior and the coast. Anticyclones form in winter, and storms in summer, reflecting the indigenous character. The entry of air masses of maritime origin is primarily possible in the west. The mountains of the northeast and east hinder the entry of air masses.
General Circulation of the Atmosphere: This explains the predominance of westerly winds and the existence of the jet stream.
The Jet Stream or Jet Stream: It is a constant stream of air flowing from west to east through the temperate latitudes at an altitude of more than 8 km and at speeds over 150 km/hour. It is the origin of cold air masses that cause storms when they coincide with warm, moist air at the surface, leading to heavy rains, mainly affecting Mediterranean coastal areas. The peninsula is not significantly affected by the jet stream due to its lower latitude.
Action Centers: As a result of general atmospheric circulation and latitude, several action centers affect Spain seasonally. These centers are located at a great distance:
- Cyclones: The Azores anticyclone (maritime tropical air, warm and humid), North Atlantic anticyclone or polar (cold air, polar and maritime), continental anticyclones mostly from Central Europe (cold and dry, originating cold waves), the Saharan anticyclone (warm air, dry continental), and the Meseteño anticyclone (indigenous, seasonal, cold).
- Lows: The low pressure of Iceland (and cold air masses that affect the sea in winter), the seasonal lows of Cadiz and Roses, and the continental thermal low pressure (affecting especially Andalusia).
Air Masses: These are driven by the action centers and include: Arctic sea, maritime polar, continental polar, maritime tropical, and continental tropical.
Fronts: When air masses of different origins and characteristics come into contact, “fronts” arise. Three major fronts affect Spain, causing precipitation and atmospheric instability. The most important, due to its duration and territorial extent, is the polar front, which affects the entire peninsula at the equinoxes and just the north in summer. The Arctic front only rarely affects the region and involves very low temperatures. The front of the trades only affects parts of Andalusia and the Canary Islands.