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Water management in Central Asia: state and impact Water management in Central Asia: state and impact
The graphic shows the effects of the shrinking of the Aral sea, and related issues, on both population migration, and environmental impacts in other areas. It also shows other water problems that could lead to tensions and conflicts.
11 Feb 2006 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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World ocean thermohaline circulation World ocean thermohaline circulation
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...
01 Jun 2007 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Example of enhanced water levels produced from river ice, Liard River, Canada Example of enhanced water levels produced from river ice, Liard River, Canada
The lower curve shows the correspondence between river flow and water levels under open-water conditions. The much greater maximum water levels possible under ice-jam conditions are illustrated by the upper curve. The transition in break-up severity from dynamic to thermal break-up effects (see text) is depicted by the gradually shaded area between the two curves. Dots are observed annual maximum water levels during the spring break up. The 1990...
01 Jun 2007 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Millennium Ecosystem Assessment conceptual framework Millennium Ecosystem Assessment conceptual framework
International demand for timber may lead to a regional loss of forest cover, which increases flood magnitude along a local stretch of a river. Similarly, the interactions can take place across different time scales. Actions can be taken either to respond to negative changes or to enhance positive changes at almost all points in this framework.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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World's top seed companies World's top seed companies
The top ten seed companies have incomes at over $10 billion USD. Monsanto and Dupont/Pioneer lead the way with over 50% of seed sales in the world. All of the top ten companies are located in the U.S.A, Japan or Europe.
03 Jan 2008 - by IAASTD/Ketill Berger, UNEP/GRID-Arendal
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Trends in real commodity prices Trends in real commodity prices
Agriculture is a fundamental instrument for sustainable development; about 70% of the world’s poor are rural and most are involved in farming. National policy needs to arrive at a balance between a higher prices which can benefit producers and lead to a more vibrant rural economy, and lower prices, which, although volatile on the international market, can improve food access for poor consumers.
03 Jan 2008 - by IAASTD/Ketill Berger, UNEP/GRID-Arendal
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Natural resources - minerals Natural resources - minerals
In more than hundred countries around the world, miners dig minerals and metals out of the ground, satisfying a slowly but continuously increasing demand from industrial production, agriculture, construction, high-tech sectors, and merchandise producers. In contrast to the other natural resources presented here, minerals are a finite resource, and the resource and their profits needs to be managed carefully to ensure sustained livelihoods after t...
12 May 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Forest vs. Agriculture – the case of the Mabira forest reserve, Uganda Forest vs. Agriculture – the case of the Mabira forest reserve, Uganda
The Mabira forest reserve, on the shores of Lake Victoria hosts valuable wildlife, serves as a timber resource, provides ecosystem services for the water balance and the rainforests represents a tourist destination. Following a proposed plan for clearing a third of the reserve for agricultural use, the values of the forest were calculated by local researchers. This economic evaluation of the forest shows that from a short-term perspective, growin...
12 May 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Temperature increases in the Antarctic due to climate change, 2090 (NCAR-CCM3, SRES A2 experiment) Temperature increases in the Antarctic due to climate change, 2090 (NCAR-CCM3, SRES A2 experiment)
Climate change, due to increased concentrations of greenhouse gases in the atmosphere, has not lead as clear changes in the Antarctic as in the Arctic. Some of the ice shelves of the Antarctic peninsula have split up and started moving more rapidly, but the analyses of the Antarctic ice sheet are inconclusive. The projected climate situation in 2090 are presented in this figure, the temperatures are annual values from the NCAR-CCM3 model, ensembl...
31 Jul 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Projected temperature increases in the Arctic due to climate change, 2090 (NCAR-CCM3, SRES A2 experiment) Projected temperature increases in the Arctic due to climate change, 2090 (NCAR-CCM3, SRES A2 experiment)
Climate change, due to increased concentrations of greenhouse gases in the atmosphere, has lead to increased temperatures and large scale changes in the Arctic. The Arctic sea ice is decreasing, permafrost thawing and the glaciers and ice sheets are shrinking. The projected climate situation in 2090 are presented in this figure, the temperatures are annual values from the NCAR-CCM3 model, ensemble averages 1-5 for the SRES A2 experiment. The ice ...
31 Jul 2008 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Trends in productivity 1981-2003 (greening and land degradation) Trends in productivity 1981-2003 (greening and land degradation)
Unsustainable practices in irrigation and production may lead to increased salinization of soil, nutrient depletion and erosion. An estimated 950 million ha of salt-affected lands occur in arid and semi-arid regions, nearly 33% of the potentially arable land area of the world. Globally, some 20% of irrigated land (450,000 km2) is salt-affected, with 2,500–5,000 km2 of lost production every year as a result of salinity (UNEP, 2008).
02 Feb 2009 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Disappearing lakes - Old Crow Basin, Canada (1951-2001) Disappearing lakes - Old Crow Basin, Canada (1951-2001)
The Arctic contains a variety of types of lakes but overall, it is thermokarst lakes and ponds that are the most abundant and productive aquatic ecosystems in the Arctic. They are found extensively in the lowland regions of western and northern Alaska, Canada and Siberia. These (i.e., thaw) lakes are most commonly formed by the thaw of ice-rich permafrost, which leads to the collapse of ground levels and ponding of surface water in the depression...
17 Mar 2010 - by Hugo Ahlenius, GRID-Arendal & CAFF
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Disappearing Arctic lakes - examples in Siberian lakes, 1973 to 1997 Disappearing Arctic lakes - examples in Siberian lakes, 1973 to 1997
The Arctic contains a variety of types of lakes but overall, it is thermokarst lakes and ponds that are the most abundant and productive aquatic ecosystems in the Arctic. They are found extensively in the lowland regions of western and northern Alaska, Canada and Siberia. These (i.e., thaw) lakes are most commonly formed by the thaw of ice-rich permafrost, which leads to the collapse of ground levels and ponding of surface water in the depression...
17 Mar 2010 - by Hugo Ahlenius, GRID-Arendal & CAFF
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Marine mammals in the Arctic Marine mammals in the Arctic
Seven species of marine mammals live in the Arctic year-round – the bowhead whale, beluga whale, narwhal, ringed seal, beaded seal, walrus, and polar bear - and many more migrate to the Arctic seasonally. Many marine mammals aggregate in specific areas across the Arctic, for example to feed, or for whelping, pupping or moulting. A common feature of marine mammals in the Arctic is that they are associated with sea ice, although the ecological rela...
13 Oct 2010 - by Riccardo Pravettoni, UNEP/GRID-Arendal
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Climate impacts and tropical diseases in Colombia Climate impacts and tropical diseases in Colombia
Shows comparative trend between air temperature in Colombia and levels of malaria and dengue fever. When temperatures increase, especially in combination with more precipitation, vector borne diseases like malaria and dengue fever increase in frequency and distribution. In particular, areas where the minimum night temperatures increase provide the best conditions for the growth and spread of Anopheline spp. and Aedes aegypti mosquitoes. (McCarth...
17 May 2005 - by UNEP/GRID-Arendal
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Traditional practices, infrastructure and development Traditional practices, infrastructure and development
Indigneous peoples have lived in Arctic for thousands of years, and continue to depend upon the natural resources of the region today. Their traditional subsistence practices include hunting, trapping, fishing and reindeer herding. All of which are conducted in a sustainable manner; that is, in a way that does not lead to long-term or large-scale degredation of the environment. However, the balance they have achieved with the environment through...
21 Mar 2006 - by Hugo Ahlenius, Philippe Rekacewicz, UNEP/GRID-Arendal
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Fishing yield Fishing yield
Three-quarters of the world’s fish stocks are currently exploited to the maximum extent, if not in excess (FAO, 2000). This exploitation has had the following impacts: - A growing variety of fishery products are being exploited. Commercial fishermen are targeting progressively smaller species at lower levels of the food chain because the main predator species are being depleted. - Most of the world’s main fishing areas are close to full exploit...
26 Jan 2009 - by Phillippe Rekacewicz, February 2006
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The disappearance of the Aral Sea The disappearance of the Aral Sea
The demise of the Aral Sea in central Asia was caused primarily by the diversion of the inflowing Amu Dar’ya and Syr Dar’ya rivers to provide irrigation water for local croplands. These diversions dramatically reduced the river inflows, causing the Aral Sea to shrink by more than 50%, to lose two-thirds of its volume, and to greatly increase its salinity. At the current rate of decline, the Aral Sea has the potential to disappear completely by 20...
26 Jan 2009 - by GRIDA
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Nitrate levels: concentrations at river mouths Nitrate levels: concentrations at river mouths
Nutrients are essential to life. In aquatic systems, nitrogen and phosphorus are the two nutrients that most commonly control the growth of aquatic plants, algae and bacteria. Nitrogen and phosphorus are considered to be the primary drivers of eutrophication of aquatic ecosystems, where increased nutrient concentrations lead to increased primary productivity. Some systems are naturally eutrophic, whereas others have become eutrophic as a result o...
26 Jan 2009 - by Philippe Rekacewicz
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Human actions leading to coastal degradation Human actions leading to coastal degradation
Physical alteration and the destruction of habitats are now considered one of the most significant threats to coastal areas. Half of the world’s wetlands, and even more of its mangrove forests, have been lost over the past century to physical alterations, the major causes being accelerating social and economic development and poor-planning (UNEP, 2002). There are currently about one billion people living in coastal urban areas. It is estimated t...
26 Jan 2009 - by Philippe Rekacewicz (Le Monde diplomatique), February 2006
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