Some countries
and cities that have become dependent on the water that
glacial melt provides, it is used for more thank drinking water and in some places it is used as the main source of power through hydro electricity. Vergara et al. (2007) have looked in
to the possible implications glacial retreat could have for the Andean region,
with particular attention paid to the economic costs that may be incurred.
An introduction to the problem
In the Andes, glacial melt water ensures a year
round water supply for agriculture, ecosystem biodiversity, power supplies and
potable water (Vergara et al., 2007). Much of the population is dependent on the water that is provided by glacial melt, unfortunately the amount of water is likely to decrease in the future and people will have to adapt to this. Modeling work implies that many of the glaciers in the region could disappear within the next 10-20 years. From 1970 to 2002 glacier cover decreased
from 2940km² to 2493km² (Kaser and Osmaston, 2002). The increased melt has seen
an increase in runoff, but this runoff is unsustainable. To put it simply, at the moment there is more
then enough water because glaciers are melting. Unfortunately, people are
dependent on this water and soon it is going to run out!
Most of the population of Peru is located
near to the Andes, with the majority of economic activity also
present here; both are reliant on the melt water. Quito is a city located in
Ecuador, home to 2 million people; when glaciers melt its local economy is likely to falter because water supplies are
at risk (Francou et al., 2000). There
are numerous projects that could alleviate the problem, none of which are
cheap.
Solving the Problem and costs
- More water sources must be
diverted to the city; a reservoir capacity close to 43 million cubic metres will
be required, this will cost US$13 million.
- Water infrastructure will have
to be built at a faster pace than was previously thought because of the lack of melt water,
this will cost US$100 million over 20 years.
Ecosystem effects
- Reduced water regulation will
mean a decrease in biodiversity, with many species of fauna not being able to
survive the seasonal changes (Mulholland et
al., 1997).
Power Generation
-
80% of power in Peru is from
hydropower.
-
An example – Average annual
power supply from the Canon Del Pato hydropower plant would drop from 1540
gigawatt-hours to 1250 gigawatt-hours with a 50% reduction in glacial runoff.
If there was no glacial runoff, this would reduce to only 970 gigawatt-hours, a
significant reduction(Vergara et al, 2007). A further example of the contribution of meltwater to total stream yield is shown in the table below, it highlights the significant decrease in yield when there is no meltwater adding to the flow.
Economic this lack of power could have
major implications for the country. It would be feasible to see rising energy costs as the supply decreases for homeowners. Hydropower plants will also see a reduced
income because of the decrease in the amount of energy they will be able to produce. All negative news for the economy (Vergara et al., 2007).
My View
Clearly the Andean region of the world has become over reliant on the water that comes seasonally from meltwater. They will not be able to continue to rely upon this water as the meltwater amount decreases with the continued reduction in glacial size. Their are numerous ways in which the countries could adapt, unfortunately though, the measures they will have to take will probably mean a lot of change at a high cost. How well each country prepares for and adapts to the inevitable decrease in water will determine how the country and the economy in particular cope with the changes.
Bibliography
Kaser, G. and Osmaston, H. (2002) Tropical Glaciers, Cambridge University
Press: New York.
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