Transcript lesson 4 Aral Sea - SLC Geog A Level Blog

Recap from the last lessons
What factors cause
water scarcity
globally?
Learning Objectives
• To consider how the global water crisis is
linked to economic, social (especially health)
and political issues
• To understand why the Aral sea is water scarce
and the role of different key players.
• To understand the impacts this has had on
human welfare and economic growth
Read p 62-67 Oxford
• Produce an A3 spider diagram to show how
the global water crisis is linked to economic,
social (especially health) and political issues
• Make sure you put named examples
Water scarcity hotspots
According to the International Water Management
Institute environmental research organisation global water
stress is increasing, and 1/3 rd of all people face some sort
of water scarcity. Agricultural uses dominate in the
growing need for food.
Aral Sea faces environmental catastrophe,
although recent attempts to reduce impacts
of river diversions for especially cotton
production
Egypt imports > 50% of its food because of
physical scarcity
Ogallala aquifer provides
1/3 all US irrigation water,
but is seriously depleted:
the water table is
dropping by about 1m/yr.
As a ‘fossil’ reserve,
formed probably from
past glacial meltwater
flows, it is effectively a
finite resource
Severe water scarcity N China,
leading to South North transfer
scheme-see later slide
R Ganges: physical stress from
pollution and over abstraction
Australia; diversion ¼ of
all water away from
Murray Darling Basin for
agriculture
Much of sub Saharan Africa suffers from
economic scarcity from especially
poverty but also lack of infrastructural
development . Some 1 bn people
involved1
Little/no water scarcity
Physical water scarcity- not necessarily dry areas but those where over 75% river flows are used by agriculture, industry or domestic
consumers
Economic water scarcity- less than 25% rivers used, and abundant supply potential but not reaching the poorest people .
Approaching physical water scarcity – More than 60% river flows allocated, and in the near future these river basins will have physical
scarcity
Water conflicts
Population growth
Consumer demand
Industrial growth
Agricultural demand
DEMANDS?
SUPPLY?
Rising
Diminishing
DIFFERENT
USERS?
Conflicting
demands
•International conflicts i.e. basin crosses
national boundaries
•Internal conflicts ie within a country
•Conservation versus exploitation
Reductions because of:
•Users abstracting/polluting
upstream
•Deteriorating quality
•Impact of climate change
PRESSURE POINT- ie need
for management.
This is shown spatially as a
‘hotspot’ of conflict, see
map on next slide.
Pressure and hence tension
and conflict may be over
surface flow and/or
groundwater supplies
Dams and diversions and
loss of wetlands are
particularly contested.
Present and potential water conflict hotspots
•
•
As water supply decreases, tensions will increase as different players try to access common water supplies
Many conflicts are transboundary in nature, either between states or countries
River basins currently in dispute
Tigris-Euphrates
Iraq + Syria concerns that
Turkey’s GAP project will divert
their water
Colorado: disputes
between the 7 US
states and Mexico it
flows through. The
river is so overused,
that it no longer
reaches the sea!.
90% abstracted
before reaches
Mexico
River basins at risk in the future
Large International drainage basins
Ob
Lake
Chad
Mekong
Ganges
Okavango
La Plata
Zambezi
Insert Figure 2.11
Orange page 47
Note: although there have been rising tensions
globally, many areas demonstrate effective
management to diffuse the situation and create
more equitable and sustainable demand-supply
balance, such as the Mekong River Committee,&
the Nile River Initiative
Nile hotly disputed
between Ethiopia and
Sudan ,who control its
headwaters, and Egypt .
The Aral Sea, an
inland drainage basin,
once the world’s 4th
largest inland lake has
shrunk sine the 1950s
after the 2 rivers
feeding it: the Amu
Dayra and Syr Darya
were diverted for
irrigation.
By 2007 the sea was
10% of original volume
and split into 2 lakes.
The ex soviet states
are in conflict:
Uzbekistan ,
Turkmenistan and
Kazakstan.
Aral Sea
Why?
‘With reference to differing
examples, explain how differing
stakeholders views could lead to
water conflict’ (15)
Aral Sea Over time
Background from Internet
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•
•
•
•
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Once the world's fourth-largest saline body of water with an area of 68,000 km2,
the Aral Sea has been steadily shrinking since the 1960s, after the rivers Amu Darya
and Syr Darya that fed it were diverted by Soviet Union irrigation projects (in what
are now Kazakhstan, Uzbekistan, and Turkmenistan) to irrigate farmland.
As its water levels dropped, the lake began splitting into smaller pieces: the
Northern (Small) Aral Sea and the Southern (Large) Aral Sea. The Southern Aral Sea
further split into eastern and western lobes.
By 2007 it had declined to 10% of its original size, splitting into three separate
lakes, two of which are too salty to support fish. The once prosperous fishing
industry has been virtually destroyed, and former fishing towns along the original
shores have become ship graveyards. With this collapse has come unemployment
and economic hardship.
By August 2009 virtually nothing remained of the Southern Aral Sea’s eastern lobe.
Much of what finally doomed the Southern Aral Sea was an attempt to save its
neighbour to the north. In 2005, Kazakhstan built the Kok-Aral Dam between the
lake’s northern and southern portions to preserve water levels in the north. The
Northern Aral Sea actually exceeded expectations with the speed of its recovery,
but the dam ended prospects for a recovery of the Southern Aral Sea, which some
authorities already regarded as beyond help.
The Aral Sea is also heavily polluted, largely as the result of weapons testing,
industrial projects, pesticides and fertilizer runoff. Wind-blown salt from the dried
seabed damages crops and polluted drinking water and salt- and dust-laden air
cause serious public health problems in the Aral Sea region. The retreat of the sea
has reportedly also caused local climate change, with summers becoming hotter
and drier, and winters colder and longer.
June 2013
Tasks
Make notes or answer the following questions on the
Aral Sea :
1. Why was it exploited?
2. Which stakeholders thought it was a good idea to
exploit – for each say briefly why?
3. Which stakeholders are against the exploitation
why?
4. What are the human welfare impacts of the
exploitation of the Aral Sea?
5. What are the economic impacts of the Aral sea
exploitation?
Information
• http://en.wikipedia.org/wiki/Aral_Sea
• http://www.telegraph.co.uk/news/worldnews
/asia/kazakhstan/9012718/Will-the-Aral-Seaever-return.html
• http://www.youtube.com/watch?v=dp_mlKJi
wxg
• http://en.tengrinews.kz/environment/Kazakhs
tan-enters-second-phase-of-Aral-Searestoration-14538/
Solutions to the Aral sea water
problem?
Many different solutions to the different problems have been suggested over the years, varying in
feasibility and cost, including:
• Improving the quality of irrigation canals
• Installing desalination plants
• Charging farmers to use the water from the rivers
• Using alternative cotton species that require less water
• Using fewer chemicals on the cotton
• Moving farming away from cotton
• Installing dams to fill the Aral Sea
• Redirecting water from the Volga, Ob and Irtysh Rivers to restore the Aral Sea to its former
size in 20–30 years at a cost of US$30–50 billion[
• Pumping sea water into the Aral Sea from the Caspian Sea via a pipeline, and diluting with
freshwater from local catchment areas
• In January 1994, the countries of Kazakhstan, Uzbekistan, Turkmenistan, Tajikistan and
Kyrgyzstan signed a deal to pledge 1% of their budgets to helping the sea recover.
• In March 2000, UNESCO presented their "Water-related vision for the Aral Sea basin for the
year 2025"[ at the second World Water Forum in The Hague.
• By 2006, the World Bank's restoration projects, especially in the North Aral, were giving rise
to some unexpected, tentative relief in what had been an extremely pessimistic picture.