Three-quarters of fish stocks are currently exploited to the maximum extent, if not excessively. The Northeast Atlantic Ocean continues to exhibit declining catches, as well as a shift towards fish at lower levels in the food chain. This graphic illustrates the decline in the catch ratios of predatory and plankton-feeding fish in the Northeast Atlantic Ocean from 1950 to 1995.

The Marine Species Population Index provides an assessment of the average change over time in the populations of 217 species of marine mammals, birds, reptiles, and fish. The index represents the average value of six regional ocean indices. More pronounced declines are seen in the southern oceans, which is attributed to the fact that major losses and degradation of marine ecosystems in the industrialised world took place prior to 1970. Marine sp...

River runoff represents the accumlated water, from preciptation and meltwater, that feeds into rivers that feeds into seas. The estimated annual figures in this graphic is what volume of water that ends up in the World Ocean. Factors influencing this volume is primarily the area that drains (e.g. area of continent), precipitation and evaporation. Tropical regions typically exhibit greater river runoff volumes. The Amazon carries 15% of all the wa...

Physical alteration and destruction of habitats are now considered one of the most important threats to coastal [and marine] areas. This graphic shows the extent to which twelve different human activities cause environmental degradation in estuaries, inter-tidal wetlands and the open ocean. The activities include the drainage of coastal ecosystems; the construction of dykes, dams and seawalls and the mining of wetlands.

The Republic of Fiji is a small island country in the South Pacific Ocean. The country has a population of 850 000 people spread out over an archipelago of islands. The largest ones, Viti Levu and Vanua Leva houses the majority of the inhabitants.

The continental shelves, ridges and sea mounts are the most productive areas in terms of biodiversity, and is of highest importance for economic activities. It is also here that natural resources extraction - such as oil and gas - takes place. The largest expanses of ocean are vast plains of depths between 1500-5000 meters. The deepest areas are the trenches where the continental plates meet, such as the Marian Trench of the Pacific.

The Arctic represents the northermost area of the World, the Arctic Ocean and the land areas that surrounds it. The region is characterized but cold temperatures, and ice and snow. The summers are short, but with long periods of daylight (midnight sun). The winters are long and cold and with periods with no sun (polar night). The Arctic Ocean is one basin that is mostly covered by sea ice, and is connected to the Pacific and Atlantic Oceans. The ...

Iceland is located in Northern Europe, is an island between the Greenland Sea and the North Atlantic Ocean, northwest of the UK, comprising 103,000 sq km. It has an estimated population of 296,737 (2005). Major environmental concerns are: water pollution from fertilizer runoff; inadequate wastewater treatment.

This map locates two groups of islands, outside continental Alaska - the Pribiliof and Aleutian Islands. These islands are located in the Pacific Ocean and the south end of the Bering Sea in the Arctic, and are a part of the USA.

Nenets Autonomous Okrug is an administrative region in Arctic Northwest Russia, covering some 176000 sq km of tundra and marshland. The capital city of the region is Narian-Mar. Off the coast are parts of the Arctic ocean know as Barents and Kara seas, and the long island in the north west is Novaya Zemlya.

Sea routes along the edges of the Arctic ocean, or rather along the coasts of Northern Canada and Russia, holds potential for decreasing the number of days in shipping goods from the Pacific to Atlantic coasts in Europe and North America, and vice versa. In addition, this could provide a means to transport natural resources, such as oil and gas, extracted in the Arctic. Currently these routes have not been possible to use this, due to the ice con...

Using the IS92 emission scenarios, projected global mean sea level increases relative to 1990 were calculated up to 2100. Taking into account the ranges in the estimate of climate sensitivity and ice melt parameters, and the full set of IS92 emission scenarios, the models project an increase in global mean sea level of between 13 and 94 cm. During the fist half of the next century, the choice of emission scenario has relatively little effect on ...

Over the last 100 years, the global sea level has risen by about 10 to 25 cm. Sea level change is difficult to measure. Relative sea level changes have been derived mainly from tide-gauge data. In the conventional tide-gauge system, the sea level is measured relative to a land-based tide-gauge benchmark. The major problem is that the land experiences vertical movements (e.g. from isostatic effects, neotectonism, and sedimentation), and these get ...

The global conveyor belt thermohaline circulation is driven primarily by the formation and sinking of deep water (from around 1500m to the Antarctic bottom water overlying the bottom of the ocean) in the Norwegian Sea. When the strength of the haline forcing increases due to excess precipitation, runoff, or ice melt the conveyor belt will weaken or even shut down. The variability in the strength of the conveyor belt will lead to climate change in...

Sea-ice draft is the thickness of the part of the ice that is submerged under the sea. Comparison of sea-ice draft data acquired on submarine cruises between 1993 and 1997 with similar data acquired between 1958 and 1976 indicates that the mean ice draft at the end of the melt season has decreased by about 1.3 m in most of the deep water portion of the Arctic Ocean, from 3.1 m in 1958-1976 to 1.8 m in the 1990s. In summary: ice draft in the 1990s...

With poverty and high population density this group of volcanic islands between Eastern Africa and Madagascar faces challenges in the management of the coastal environment. The islands are fringed by magnificent coral reefs, and the waters houses the rare coelacanth fish. Among the responses there have been initiatives to encourage ecotourism and the support in establishing the 400 km2 Mohéli Marine Park.

The population has rapidly increased in Africa, to reach approximately 905 million inhabitants by 2005. The rate of the annual growth is levelling out after seeing a peak around 1990. Out of the sub-regions, the population is fairly evenly distributed, as indicated in the pie-chart, with Central Africa trailing behind the others, and the Western Indian Ocean islands with the smallest share out of the total population.

The Caspian Sea has internal drainage, which means that it does not have an outlet to the World Ocean. All water entering the sea accumulates or evaporates. The sea surface salinity in the sea exhibits a gradient, with the semi-encludes bay of Kara-Bogaz-Gol having the most saline water. This bay was closed between 1980 and 1992.

This chart shows eight different sources of renewable energy and explains advantages and drawbacks of each - wind, sun (photovoltaic and thermal), geothermal, wood, ocean, waste, water (hydroelectricity).

Multiple stresses make most of Africa highly vulnerable to environmental changes, and climate change is likely to increase this vulnerability. This graphic shows which of the regions of Africa (North Africa, West Africa, Central Africa, East Africa, Southern Africa and the Western Indian Ocean Islands) are most vulnerable to specific impacts of climate change. These impacts include desertification, sea level rise, reduced freshwater availability,...