Most of Spain’s national territory is located on the Iberian Peninsula – which it shares with Portugal and Andorra – situated in the southwest corner of Europe. However it also comprises the Canary Islands and the Balearics, a few smaller islands, and the cities of Ceuta and Melilla in North Africa.
With a surface area of 506,030 square kilometres, Spain is among the fifty largest countries in the world. The mainland territories occupy an area of 493,514 square kilometres; the Balearic Islands, 4,992 square kilometres; the Canary Islands, 7,492 square kilometres; and the cities of Ceuta and Melilla, 32 square kilometres.
The geological history of the Iberian Peninsula has given rise to mountains organised in large chains surrounding a high inland plateau situated at over 600 metres above average sea level. As a result of this layout, the peninsula is characterised by a rich variety of unique enclaves and natural environments. If there is one characteristic that differentiates the surface of the peninsula from the rest of Europe, it is clearly its diversity.
Due to its geographic location, Spain is influenced by two very different seas: the Atlantic Ocean, vast and open; and the Mediterranean Sea, whose only physical connection to the former is the narrow opening of the Straits of Gibraltar, which permits the exchange of water between the two masses of very different salinity and temperature. The Spanish coastline is 5,755 kilometres long.
The surface of Spain is extremely varied and characterised by a relatively high average altitude – over 600 metres above sea level. As such, it is the second-highest country in Europe, surpassed only by Switzerland, where the average altitude is 1,300 metres. This is due to the presence at the centre of the peninsula of a vast plateau, known as the Meseta, divided into two smaller plateaus by the Sistema Central mountain range. A series of other mountain ranges around the plateau and yet others located on the periphery of the peninsula round out the topography. There are two depressions – the Ebro and the Guadalquivir river valleys – located between the Meseta and the peripheral ranges. The mountain ranges, which except for the Sistema Ibérico (Iberian System) and the Cordilleras Costero-Catalanas (Catalonian-Coastal Ranges) generally run from west to east exert a tremendous influence on the continental climate by creating natural barriers against banks of moist air from the Atlantic Ocean, which would otherwise temper inland temperatures.
The natural fluvial regime of Spain’s rivers mainly depends on the pattern of precipitation, where its waters originate and transform into surface water or groundwater runoff. However, this natural fluvial pattern is affected by human action in the form of infrastructures used to regulate and modify its temporal distribution, as well as other types of actions that remove volumes of water from rivers.
The diversity of climates in Spain, together with other morphological and geological factors, explains the enormous contrasts in its present-day hydrographical composition.
Although the climates in Spain are difficult to classify because of their heterogeneity, it is possible to distinguish the following types:
- Atlantic or Oceanic Climate
- Continental Climate
- Mediterranean Climate
- Mediterranean Mountain Climate
There are other smaller but nevertheless significant climate zones, as follows:
- Cold Steppe Climate
- Hot Steppe Climate
- Subtropical Climates
With regard to temperature, the most notable differences are between the inland and the peripheral areas. In the former, where temperatures are influenced by the continental factor, the winters are very cold, with average January temperatures ranging between 0 and 3ºC, while the summers are hot, with an average of 24ºC in July and August. Meanwhile, in the peripheral areas the winters are mild, with an average of 10ºC in January, and an average annual temperature, especially on the Mediterranean coast, of between 16 and 18ºC.
Precipitation is also marked by sharp contrasts: the north and northwest, which are directly influenced by the Atlantic, have abundant rainfall and no distinguishable dry season. This area is sometimes known as La España Húmeda, or Wet Spain, with annual precipitation exceeding 600 mm and rising occasionally to 2,000 mm. The remainder of the country is predominantly dry, with an annual precipitation of less than 600 mm. The southeast of Spain is semi-arid, with annual precipitation below 300 mm and a semi-desert landscape that at times is reminiscent of the Sahara.
Spain’s rich diversity in terms of its climate, petrography and topography has given rise to the formation of clearly defined ecological compartments, which in turn have led to the development of a broad spectrum of vegetation types. Another factor is the intensity of human activity, which has gradually transformed nature since the Neolithic period, often adding to the already diverse array of habitats.