Sunset, Renney Rocks near Plymouth

Source: Spectrum Colour Library


EXTENT AND BOUNDARIES

Europe is a continent apparently distinct and precise on its western boundaries, but less well-defined in the east (see Map 3.1). Europe stretches from tundra in the north to Mediterranean and desert climes in the south. It abuts Asia in the east, shares the Atlantic with the Americas, and the Mediterranean with Africa and the Middle East. The air it shares with the globe.

The exact boundaries of what constitutes Europe is a controversial matter. It is neither well defined, nor the subject of common agreement. Particularly difficult to decide whether or not they are part of Europe are outlying islands and countries such as Greenland, the arctic islands, Turkey and the trans-Caucasian republics. In the main, this report uses the common geographical definition which excludes the trans-Caucasian republics, Greenland and Anatolia. The border with Asia is taken to follow the Ural mountains, the river Ural to the Caspian Sea, the Manych valley to the Sea of Azov and the Black Sea, and the Bosporus. Being an environmental report, however, it focuses on environmentally significant geographical units which may straddle the often artificial borders created by this definition, for example when considering river catchments or sea areas.

GEOGRAPHY AND GEOLOGY

Europe forms little more than 7 per cent of the land surface of the Earth. It is the second smallest continent, being nearly 30 per cent larger than Oceania, but less than a quarter of the size of Asia. Its length from Nordkapp (71š12'N) in Norway, to Cape Matapan, in the south of Greece (36š23'N) is about 3850 km, and its breadth from Cabo da Roca in Portugal to the Urals is about 5050 km.

Four major morphological zones can be distinguished:

  1. the old Fennoscandian Shield and Caledonian range, consisting of the Scandinavian highlands, and the north and west of Ireland and the UK;
  2. the North European Plain from France to Russia;
  3. the central and southern European Highlands, comprising the Sierra Nevada, Pyrenees, Alps, Apennines, Carpathians and the Balkans, and;
  4. the littoral zone of the Mediterranean.

On the fringe of the bulky Eurasian landmass, Europe appears like an appendage. As a continent it is very fragmented; its mountain ranges and hydrographic network divide up the landscape, and its peninsulas, islands and archipelagos give it complexity and interest. Indeed, 'an aggregation of peninsulas' (from Iberia to Scandinavia, Italy and Greece) describes the continent well. These diverse characteristics combine to give Europe a rich variety of landscapes in a comparatively small area.

Much of Europe's history, economy, landscapes and traditions have been tightly connected to the close presence of the sea. In the western part of the continent there are few areas more than 200 km from the coast. The continent is surrounded by nine identifiable sea basins, including the world's two largest land-locked seas, the Caspian and the Black Sea.

Europe's morphology has been shaped from north to south by successive periods of mountain building (see Map 3.2). The oldest rocks found in Europe ­ the Precambrian shields (approximately 3500 to 540 million years old) and rocks of the Palaeozoic period (approximately 540 to 245 million years old) ­ cover most of the northern part of the continent including Scandinavia, the Russian Federation and Ukraine, large parts of Britain and Ireland, Brittany and parts of Spain. The more recent rocks of the Mesozoic period (245 to 65 millions years ago) and the Cenozoic period (from 65 to 2 million years ago) form a continuous belt across north and central Europe from the North Sea into Russia.

Until about 60 to 70 million years ago, Greenland and Scandinavia were parts of the same continent. Northern Europe, of old geological formation, has stabilised, while parts of the south are still unstable as shown by the active volcanoes and the frequency of significant earthquakes. Most types of important mineral resources are found in Europe, distributed unevenly across the continent according to geology. Thus, important deposits of coal are found in Belgium, the Czech Republic, France, Germany, Poland, the Russian Federation and the UK, while these same countries, plus Austria, Spain and Sweden, have deposits of iron ore. Copper, lead, zinc, gold, platinum, silver, mercury, sulphur, and graphite are all found in Europe. There are large oilfields in the Caucasus, Ukraine and Romania and both oil and natural gas offshore beneath the North Sea and Caspian Sea.

Large parts of the continent have been shaped during the Quaternary era (the last 2 million years) and in particular by the last glaciation which ended approximately 10 000 years ago. A great deal of Europe's soils were formed in this era in connection with the many inland ice periods. A characteristic feature of Europe is the Alpine ridge, a permanent divide in the continent for climate, history and trade. The plains are home to most economic and social activities; the so-called 'cradle' of European welfare and power.

This complex and fragmented geography and geology has to a large extent driven Europe's history and its political and territorial complexity. Geography and geology have contributed significantly to the political subdivisions found in Europe today, as well as to the conflicts and changes which have occurred and continue to influence the configuration of European countries and regions. Nowhere in the world is there such a multitude of independent states in such a small area. This provides both richness and also scope for enormous disparities arising from the variety and differences in culture, religion, language, lifestyle and habits. The potential for transboundary problems with environmental consequences is thus of particular significance in Europe.

Europe covers an area of 10.2 million km2. At the end of 1993, geographical Europe embraced the whole of 43 independent states, and included parts of three others (the Russian Federation, Turkey and Kazakhstan) (Map 3.3). These states vary enormously in size, from 4.25 million km2 for the European part of the Russian Federation, to 0.44 and 1.95 km2 for the two smallest independent states in Europe, the Vatican City and the Principality of Monaco respectively.

Two major political groupings of European countries, the European Union (EU) and EFTA, comprise 19 of these independent states, making up 35.3 per cent of Europe's total surface area. In Central and Eastern Europe (including the European parts of the Russian Federation, Kazakhstan and Turkey) a further 21 states can be found (64.5 per cent of the surface of Europe). The remaining area of Europe is made up of 4 small continental states (Andorra, Monaco, San Marino and Vatican City) and 2 island territories (Cyprus and Malta).

Since this report was requested (June 1991), 3 states have ceased to exist in Europe (Czechoslovakia, the USSR and Yugoslavia) and 14 new countries have come into being; 7 from the European part of the former USSR (involving approximately 52 per cent of the land surface of Europe), 2 from former Czechoslovakia, and 5 from Yugoslavia.

The country groupings mentioned above are frequently referred to in the report to present information. In some cases the data necessitate alternative arrangements and then the country coverage is explained. Furthermore, some chapters use particular physical or geographical regions in which to present the data, these are either dictated by available statistics or more relevant to the topic under discussion and largely related to important landuse characteristics. These are defined explicitly at the appropriate place in the report.

CLIMATE

The complex and fragmented structure of Europe contributes to the variable meteorological and climatological conditions: from Mediterranean in the south, through temperate oceanic in the west and temperate continental in the east, to boreal in the north. These main types contain many subdivisions linked to altitude (eg, Alpine climate), position and aspect in plains or valleys, and the distance from the sea. Temporal variations of climate have also influenced historical and economic development. The following succinct description is based on the monograph of Martyn (1992).

Europe lies across three climatic zones:

  1. the circumpolar zone ­ the northern tip of Scandinavia, the Svalbard archipelago and northern Iceland;
  2. the subtropical zone ­ the area south of the Pyrenees, Alps, Dinaric Alps and Balkans;
  3. the temperate zone ­ warm in the central south and west, and cool further north especially in eastern Scandinavia and Finland.

The climatic features of Europe also change in an easterly direction: the greater the distance from the Atlantic, the more the climate becomes continental (ie, drier, with greater seasonal and diurnal temperature regimes).

The influence of the Atlantic is strongly felt owing to the warm North Atlantic Current or Drift originating from the Gulf Stream which reaches the shores of western Europe beyond 45šN (mainly fetching up on the coasts of Ireland, Britain and Norway, as well as all the way to the Russian island of Novaya Zemlya). Thanks to this current, the whole area experiences a positive temperature anomaly in winter which gradually decreases south and eastwards across the continent.

Europe's latitudinal position on the globe, between 36 and 71šN, determines the duration of incoming light and heat from the sun. Annual sunshine totals vary from 1000 hours in the cloudiest areas of eastern Iceland, the Faeroes and western Scotland, 1400 to 1600 hours in northwest central Europe to 2800 to 3000 hours in the southern Mediterranean, and even over 3400 hours in Portugal and southeast Spain.

The atmospheric circulation over Europe is established in the presence of permanent cyclonic centres stationed over the North Atlantic (the Icelandic Low), and of the Azores High. In winter, Europe may come under the influence of the seasonal Asian high, and lows moving in from the Atlantic into the Mediterranean basin or forming further north. Summer is characterised by the presence of the Arctic High in the Svalbard region and the South Asian Low. This pressure system gives rise to prevailing southwesterlies over Northern, Western and Central Europe, and northwesterlies and westerlies in Southern Europe (see Map 3.4). The characteristic feature of the climates of Northern, Western and Central Europe is the changeability of the weather. Summer in Southern Europe is much more reliable under the influence of tropical air masses.

These insolation and circulation conditions are well reflected by the air temperature distribution. In January, when thermal conditions are determined by the atmospheric circulation, the isotherms run latitudinally. The 0šC isotherm can be regarded as the boundary between the warm south and west of Europe and its cool centre and north. In July, insolation affects the continent far more than the atmospheric circulation does, although all along the Atlantic fringe the reverse is still the case. The shape of Europe and the dominant westerlies cause the continentality of the climate to increase eastwards, as shown by the annual temperature amplitude. It increases from 8 to 10šC in Iceland, along the Irish and British coasts and Portugal, and from 14 to 16šC along the Atlantic coast of Scandinavia to 20šC in the Iberian Meseta, the Lombardy plain, the lee of the Scandinavian mountains, the Baltic States, central Poland, the Middle Danube plain, the Dinaric Alps and southern Greece. A more continental climate is found in the Middle Danube and Wallachian plains (25 to 26šC), Lapland and eastern Finland (26 to 28šC), as well as central Russia.

Moist air masses from the Atlantic cause the largest amounts of precipitation to fall on western coasts and mountain slopes. In such places the annual precipitation (see Map 3.5) may exceed 1000 to 2000 mm and, in particularly exposed spots, may even reach 3000 to 4500 mm (western parts of Britain and Ireland, Norway, the Iberian and Balkan peninsulas, southern and northern slopes of the Alps and the western Pyrenees). Precipitation is scantiest (300 to 500 mm per annum) in the southeast of the Mediterranean peninsulas, chiefly southeast and central Spain, southeast Italy and eastern Greece. Under 500 mm per annum falls in Sweden, in the Baltic States, central Poland, the Middle Danube plain, the Dinaric Alps and southern Greece.

Although small, Europe has a wide mosaic of seasons of maximum precipitation, reflecting the influence of orography. Southern Europe has a dry season (spring and summer) which lengthens eastwards and southwards. The rest of Europe has precipitation all the year round, western coasts receiving more in autumn and winter. As a sign of increasing continentality, the proportion of more abundant summer rain grows eastwards from southeast Sweden and west-central Europe. In the Alps and the interior lowlands, however, rainfall is more plentiful in spring. Both the particular climate and the orography contribute to the accumulation of waters in the Alps. Thus Switzerland is the water tower of Europe. The main watercourses leaving the country flow either towards the North Sea (Rhine), or towards the Mediterranean Sea (Rhone). A smaller area of territory belongs to the catchment areas of the Po (Adriatic) and the Danube (Black Sea).

The interplay between natural conditions and cycles and anthropogenic influences can sometimes lead to undesirable conditions being reinforced. In winter, for example, maximum emissions of pollutants often combine with periods of maximum precipitation leading to washout and greater than expected environmental impacts. Under drier, colder, conditions (due to latitude or altitude), many pollutants have longer residence times, leading to a build-up in the atmosphere during winter; at the start of spring ­ a critical phase in biospheric cycles ­ the pollutants can still be abundant.

BIOGEOGRAPHY

In addition to the differences in geology and climate across Europe presented above, there are also large variations in vegetation. The combination of geological, morphological and climatological features determines (and is partly determined by) the distribution of soil and vegetation patterns (see Chapter 7, for a generalised soil map of Europe). Climatic conditions modulate the close relationships between soil and vegetation. Distinct geographical areas having their own specific character and originality can be identified by the composition of natural plant and animal life. These can be grouped into different biogeographic provinces as illustrated for Europe in Map 3.6.

Within the northernmost borenomoral zone (subpolar belt) can be found permafrost and tundra (a permanently frozen soil layer reaching down to 400 m below the surface) maintained by long cold winters lasting from September to June. Running alongside and to the south of the borenomoral zone is the taiga, a wide cool and moist temperate climate belt dominated by coniferous forests.

The Boreonemoral province resembles a slightly mixed coniferous forest. The southern limit in Sweden is the northern limit of the beech (Fagus sylvatica) forests. The Pontian province covers the true steppes of Eastern Europe (grasslands) and the steppe-woodland belt of Ukraine.

Central and Southern European vegetation is not distributed in clear tracts across the continent; instead, due to the complex morphological and climatic patterns, a mosaic of various types is created. The Pannonian province is recent in origin and secondary in nature; it has a steppe-like appearance and covers the plains of the Middle Danube in the Carpathian basin. This latter belongs to the woodland-belt with riparian oak-forests mixed with Central European forests. The Continental province is the heartland of the West Palaearctic broadleaved deciduous forest. The Central European Highlands include the Pyrenees in the west, the Alps proper, the Caucasus in the east, as well as northern outliers. In this province there is much Mediterranean influence and endemism.

The Atlantic province, covering western Denmark, southwest Norway, Ireland, the UK and western France, is under the influence of a mild oceanic climate. Evergreen dwarf shrubs grow where forests cannot establish themselves for climatic or cultural reasons.

The area of typically winter-rain, broadleaved evergreen, sclerophyllous vegetation is the Mediterranean province bordering, in most parts, the Mediterranean Sea. Endemics abound in Mediterranean flora and fauna and are spread throughout the region. In the warm temperate climatic belt, Mediterranean types of vegetation (forests, scrubs and brushwoods) with resistant and hard leaves are prominent.

The semi-arid regions of Central, Southern and Eastern Europe, with few or no trees, are essentially dominated by grass-like (graminaceous) species with fertile chernozem soil (see Chapter 7).

LAND-COVER AND LANDUSE

In the absence of human interference, the prevailing conditions defined by the various biogeographical provinces described above would determine the land-cover in Europe. This would result in a vegetation cover very different to that which is found today; a view of what this might look like is illustrated in a map of 'potential natural vegetation' (see Map 9.1).

Few areas of Europe remain in their 'natural' conditions. Those that do are mainly found at the extremities of the continent (mountains, lakes, islands) and in northern and eastern regions. Actual land-cover depends upon the level of human habitation and the degree and type of human activity and exploitation of the land. In most parts of Europe this has created entirely artificial landscapes principally as a result of the practices of agriculture, forestry or the construction of settlements (particularly, large urban areas). Although artificial, such areas are not necessarily poor in biodiversity. Land is subject to many competing uses or functions and, being a finite resource, conflicts often arise between them. These pressures on land as a resource are addressed in Chapter 13 wherein the exploitation of Europe's natural resources is examined.

The way that land is used has a primary influence on the type of pressures which are allowed to act on the environment. An assessment of the actual landuse in Europe is illustrated in Map 3.7. This assessment (Van de Velde et al, 1994) calculates that about 42 per cent of total land area in Europe serves some agricultural purpose, 33 per cent is covered by forest and 24 per cent by mountains, tundra, etc.

These percentages, however, vary greatly between countries:

Some comparisons of land and landuse statistics per inhabitant between Europe and other world regions are found in Table 3.1. These show Europe to be 2 to 3 times more densely populated than the USA or Africa, but about half as much as Asia (excluding the republics of the former USSR). Recent figures show that, per inhabitant, only Africa and Asia (as defined above) have less arable land for food production than Europe. With regard to forests and woodlands, only the areas of Asia outside the former USSR have less than Europe.