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THEMATIC SLIDES. WATER AND LAKES Lake Chad, Nigeria, Niger, Chad, Cameroon Challawa Gorge Dam, Nigeria Lake Nakuru, Kenya Lake Victoria, Uganda Lesotho.

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Presentation on theme: "THEMATIC SLIDES. WATER AND LAKES Lake Chad, Nigeria, Niger, Chad, Cameroon Challawa Gorge Dam, Nigeria Lake Nakuru, Kenya Lake Victoria, Uganda Lesotho."— Presentation transcript:

1 THEMATIC SLIDES

2 WATER AND LAKES

3 Lake Chad, Nigeria, Niger, Chad, Cameroon Challawa Gorge Dam, Nigeria Lake Nakuru, Kenya Lake Victoria, Uganda Lesotho Highlands Water Project, Lesotho Aral Sea, Kazakhstan Lake Balkhash, Kazakhstan Kara- Bogaz -Gol (KBG), Turkmenistan WATER AND LAKES Estimated global water loss in irrigation Source: FAO

4 Dead Sea, Jordan Lake Hamoun, Iran Mesopotamia Marshlands, Iraq Three Gorges Dam, China Atatürk Dam, Turkey Gabcikova, Slovakia Lake Chapala, Mexico Everglades, United States WATER AND LAKES Three Gorges Dam, October 24, 2003: Digital Globe

5 WATER FACTS Demand for and use of freshwater has tripled over the past half century, as world population has grown from 2.5 to 6.45 billion people Sources: Asian Development Bank; BBC; Earth Observatory; UNEP; UNESCO Of the 0.5% useable freshwater, irrigation accounts for 70%, industry 20% and household 10% Experts predict that by 2025 global water needs will increase with 40% more required for cities and 20% for growing crops The satellite photos show major freshwater depletion taking place on all continents, notably in the Dead Sea, the Aral Sea, Lake Chad, the Mesopotamian Marshlands, the Everglades and other water sources According to UNESCO estimates, by 2030 global demands for fresh water will exceed the supply with potentially disastrous consequences Of total world water, 97.5% is salty water and only 2.5% is freshwater of which useable freshwater accounts for about 0.5%

6 WATER FACTS Water withdrawals are causing major rivers—such as the Colorado, the Nile, the Yellow Rivers—to run dry, lakes to vanish and groundwater tables and aquifers to drop almost everywhere In 2002, around 3.16 billion people (82%) in the Asia Pacific region had access to improved water supplies, up from 74% in 1990 Sources: Asian Development Bank; BBC; Earth Observatory; UNEP; UNESCO Over the next 20 years, average water supply per person is estimated to drop by a third, endangering human health, agriculture and the environment Water pollution is a serious threat to the world’s water supply Water volume in the Aral sea has dropped by about 80% since 1960s, due to extensive irrigation primarily for cotton production Current water levels in Lake Victoria are below normal and the lowest level since September 1961

7 Shrinking Lake Chad Nigeria, Niger, Chad, Cameroon Persistent drought has shrunk the lake to about a tenth of its former size 1972: Larger lake surface area is visible in this image 2001: Impact of drought displays a shrunken lake, comparatively much smaller surface area than in 1972 image

8 Impact of Challawa Gorge Dam, Nigeria These images show the area before and after construction of the dam. 1990: Image of the area before the completion of the dam in : Impact of flooding upstream from the dam; colour of the water in the flooded area indicates high sediments

9 Land cover degradation around Lake Nakuru, Kenya These images show the land cover degradation in the lake’s catchment 1973: The area that hosts the world’s largest concentration of flamingos 2000: Excision of forest in the Eastern Mau Forest Reserve (white lines) will most likely lead to disappearance of upper catchment forest cover

10 Water hyacinth in Lake Victoria Uganda These images show water hyacinth infestation and control of such invasive species 1995: Image shows several water-hyacinth-choked bays (yellow arrows) 2001: A visible reduction of Water Hyacinth, after its removal from Lake Victoria, contributes to human prosperity

11 Population growth around Lake Victoria Uganda The population growth around 100 km buffer zone of the Lake Victoria Population growth around Lake Victoria, East Africa, is the highest in Africa

12 Fastest growing rural population around Lake Victoria, Uganda

13 Lake Victoria vs. Africa

14 Title Body text Height variation of Lake Victoria, Uganda Lake Victoria Height Variations

15 Title Body text Monitoring Lake Victoria, Uganda Current water levels are below normal and the lowest level since September, 1961

16 The Lesotho Highlands Water Project diverts water for South Africa’s urban and industrial use 1989: Image of the area before the completion of the dam in : Katse dam created an enormous reservoir, the extent of which can clearly be seen in this image Changes due to dam construction in Lesotho Lesotho

17 Death of a sea - Aral Sea, Kazakhstan Images show death of the world’s fourth largest inland sea 1973: The surface of the sea once measured km : 60% of the volume had been lost : The sea is now quarter of the size it was 50 years ago

18 Alarming drop in Lake Balkhash’s water level Kazakhstan : Excessive use and waste of lake water are causes of the drop 2001: Smaller neighbouring lakes appear to be drying up

19 Kara-Bogaz-Gol – Lagoon of the Caspian sea Turkmenistan Caspian Sea is the largest inland body of water in the world 1988: KBG is the large shallow lagoon of the Caspian sea 2000: Caspian Sea levels are higher than 1978 levels and water flows freely into salty waters of KBG

20 1973: The Sea level is dropping at the rate of 1m/year Dramatic changes in Dead Sea, Jordan Images show dramatic changes in the Dead sea over 30 years 2002: Notice the expansion of salt works, and near-complete closing off of the southern part by dry land

21 Changes in water levels on Lake Hamoun Iran Changes in water levels on Lake Hamoun 1976: The amount of water in the lake is relatively high : The lake dried up and disappeared

22 Demise of an ecosystem – Mesopotamian Marshlands, Iraq Upstream damming as well as drainage activities in the marshlands themselves have significantly reduced the quantity of water entering the marshes : Most of the wetlands disappeared

23 Restoration of the Mesopotamia Marshlands in Iraq 2000: Water returns to the Mesopotamian Marshlands 2004: Greening of some of the Marshlands in recent years

24 Changes due to Three Gorges Dam construction, China Changes due to the construction of dam 1987: Nature of the river and surrounding landscape before the dam 2004: The enormous dam is clearly visible

25 Changes due to Atatürk Dam, Turkey Development of Harran region is strikingly apparent in these images Right-hand corner of the 1999 image shows irrigated fields surrounding the town of Harran The dam provides power and irrigation water

26 Damming around Gabcikova, Slovakia : Images show changes brought about by massive re-channeling of river water

27 Country’s largest natural lake - Lake Chapala Mexico 1983: Level of the lake has declined; noticeable decreases in wetlands 2001: Alteration in the contours of the shoreline is clearly visible

28 Urban encroachment in Florida’s Everglades United States 1973: Rapid urban expansion has converted farmlands to cityscapes 2002: Existence of vast wetlands “Everglades” threatened by urban encroachment

29 Lake Kivu, Congo/Rwanda Lake Alaotra, Madagascar Lake Al Wahda, Morocco Lake Cahora Basa, Mozambique Lake Chivero, Zimbabwe Lake Djoudj, Senegal Lake Ichkeul, Tunisia Lake Manantali, Mali Lake Sibaya, South Africa Songor Lagoon, Ghana Lake Tonga, Algeria WATER AND LAKES

30 LAKE FACTS According to the WORLDLAKE database, there are 677 lakes in Africa There are 15 natural lakes that cross the political boundaries of two or more countries in Africa Lake Chad’s surface area has shrunk by 95 per cent over the past 35 years There are 60 transboundary river basins in Africa, covering over 63 per cent of the continent’s land area Sources: UNEP 2006 Uncontrolled damming, the withdrawal of water for irrigation, and climate variability are the major causes of drying up of Lake Tonga in Algeria Population growth around Lake Victoria, the continent’s largest lake, is significantly higher than the rest of Africa Some lakes in central Africa have become known as “killer lakes,” because of the catastrophic natural events that have occurred in their vicinity

31 Lake Kivu-one of Africa’s “killer lakes” Congo/Rwanda These images show dramatic changes before and after the eruption of Mt. Nyiragongo in : Before the January 2002 eruption 2003: Shows the track of the lava flow

32 Severe flooding around Lake Alaotra Madagascar These images show flooding over a wide area Flooding destroys significant portion of crops Intensive rice irrigation occurs at the western part of the lake (yellow arrows)

33 Impact of Al Wahda reservoir in Morocco These images illustrate the change in land cover 1987: The area before the construction of dams 2001: The area after the construction of 110 large dams

34 Cahora Basa – Mozambique’s largest dam on the Zambezi River These images show spectacular changes in the Zambezi riverine system 1972: The Zambezi River a few years before the dam construction 1999: This image shows part of the enormous dam and the lake

35 Invasive water weeds in Lake Chivero, Zimbabwe These images show overall reduction in water weeds 1989: Weeds show up as green strands along the edges of the lake 2000: This image shows that water weeds remains a persistent problem

36 Rejuvenation of the Djoudj Sanctuary in Senegal These images show the Djoudj Sanctuary before and after the construction of the Diama Dam 1979: Shows the impact of drought on the Djoudj Sanctuary 1999: Rejuvenation of the Sanctuary wetlands due to significant floods

37 Ecological changes around Lake Ichkeul, Tunisia These images show the impact of damming 1972: Shows the three feeder rivers supplying the lake before they were dammed 2000: Shows the location of the dams (yellow arrows)

38 Agricultural expansion around Lake Manantali, Mali These images show the expansion of irrigated agriculture 1977: Shows the original meandering nature of the Bafing River 1999: Shows the expanded irrigated land and increase in lake water quantity

39 Lake Sibaya – wetland of international important in South Africa These images show increase in cultivation around the lake 1991: Lakeshore is home to the only known species of a rare climbing orchid 2001: The yellow arrows vividly show the increase of cultivation of marginal lands around the lake

40 Reduction in the surface area of Songor Lagoon, Ghana These images show a conspicuous reduction in the surface area 1990: Shows major lagoon system associated with Volta river estuary 2000: This image shows water area dramatically reduced, exposing bare ground

41 Changes in and around Lake Tonga Algeria These images show the changes brought about by damming of the feeder rivers 1988: Lake Tonga before the damming of feeder rivers 2000: Damming increased irrigation and drastically reduced the volume of water entering the lake

42 One Planet Many People: Atlas of Our Changing Environment Thank You! Free Downloads: Purchase: WATER


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