It is widely acknowledged that greenhouse gas emission-fueled
climate change is having a profound and negative impact on fresh water
systems around the world. Warmer weather causes more rapid evaporation
of lakes and rivers, reduced snow and ice cover on open water systems,
and melting glaciers.
What is less understood is that our
collective abuse and displacement of fresh water is also a serious
cause of climate change and global warming. If we are to successfully
address climate change, it is time to include an analysis of how our
abuse of water is an additional factor in the creation of global
warming as well as solutions that protect water and watersheds.
There
are two major factors. The first is the actual displacement of water
from where it is sustaining a healthy ecosystem as well as healthy
hydrologic cycles. Because humanity has polluted so much surface water
on the planet, we are now mining the groundwater far faster than it can
be replaced by nature. New Scientist reports of a "little-heralded
crisis" all over Asia as a result of the exponential drilling of
groundwater. Water is moved from where nature has put it in watershed
and aquifers (where we can access it) to other place where it is used
for flood irrigation and food production - where much of it lost to
evaporation - or to supply the voracious thirst of mega cities, where
it is usually dumped as waste into the ocean.
Water is also lost to ecosystems through
global trade - water used in the in the production of crops or
manufactured goods that are then exported (known as virtual trade in
water). Over 20% of daily water used for human purpose is exported out
of watersheds in this way. Water is also piped across long distances
for industry leaving behind parched landscapes.
The second
factor is the removal of the vegetation needed for a healthy hydrologic
cycle. Urbanization, deforestation and wetland destruction greatly
destroy water-retentive landscapes and lead to the loss of
precipitation over the affected area.
Slovakian scientist
Michal Kravcik and his colleagues explain that the living world
influences the climate mainly by regulating the water cycle and the
huge energy flows linked to it. Transpiring plants, especially forests,
work as a kind of biotic pump, causing humid air to be sucked out of
the ocean and transferred to dry land. If the vegetation is removed
from the land, this natural system of biosphere regulation is
interrupted. Soil erodes, reducing the content of organic material in
the ground, thus reducing its ability to hold water. Dry soil from lost
vegetation traps solar heat, sharply increasing the local temperature
and causing a reduction in precipitation over the affected area. This
process also destroys the natural sequestration of carbon in the soil,
leading to carbon loss.
Of course, these two factors are
deeply related. Just as removing vegetation from an ecosystem will dry
up the soil, so too will removing water from an ecosystem mean reduced
or non-existent vegetation.
Taken together, these two
factors are hastening the desertification of the planet, and
intensifying global warming. Even if we successfully address and
reverse greenhouse gas emissions and our dependence on fossil fuels,
Kravcik says, we will not be able to stop climate change if we do not
deal with the impact of our abuse of water on the planet.
Unless
we collectively address the crisis of fresh water and our cavalier
treatment of the world's water systems, we will not restore the climate
to health.
Restoration of Watersheds
The solution to
the water half of this crisis is the massive restoration of watersheds.
Bring water back into parched landscapes. Return water that has
disappeared by retaining as much rainwater as possible within the
ecosystem so that water can permeate the soil, replenish groundwater
systems, and return to the atmosphere to regulate temperatures and
renew the hydrologic cycle. All human, industrial and agricultural
activity must become part of this project, which could employ millions
and alleviate poverty in the global South. Our cities must be ringed
with green conservation zones and we must restore forests and wetlands
- the lungs and kidneys of fresh water. For this to be successful,
three basic laws of nature must be addressed.
1) It is
necessary to create the conditions that allow rainwater to remain in
local watersheds. This means restoring the natural spaces where
rainwater can fall and where water can flow. Water retention can be
carried out at all levels: roof gardens in family homes and office
buildings; urban planning that allows rain and storm water to be
captured and returned to the earth; water harvesting in food
production; capturing daily water discharge and returning it clean to
the land, not to the rising oceans.
2) We cannot continue to
mine groundwater supplies at a rate greater than natural recharge. If
we do, there will not be enough water for the next generation.
Governments everywhere must undertake intensive research into their
groundwater supplies and regulate groundwater takings before these
underground reservoirs are gone. This may mean a shift in policy from
export to domestic and local production.
3) We must stop
polluting our surface and groundwater sources - and we must back up
this intention with strict legislation. Water abuse in oil and methane
gas production and in mining must stop. We must wean ourselves of
industrial and chemical-based agricultural practices and listen to the
many voices sounding the alarm about the rush toward water-guzzling bio
fuel farming. We need to promote "subsidiarity," whereby national
policies and international trade rules support local food production in
order to protect the environment and promote local sustainable
agriculture. Such policies also discourage the virtual trade in water.
Countries should also limit or ban the mass movement of water by
pipeline. Government investment in water and wastewater infrastructure
would save huge volumes of water lost every day. Local laws could
enforce water-harvesting practices at every level.
Toward a Water Secure World
Clearly,
for this rescue plan to be successful, governments around the world
must acknowledge the water crisis and the part the role water abuse
plays in the warming (and drying) of the planet. This in turn means
that a nation's water resources must be considered in every government
policy at all levels. Nations must undertake intensive studies to
ascertain the health of watersheds and groundwater reserves. All
activities that will impact water must conform to a new ethic - backed
by law - that protects water sources from pollution and over-pumping.
This will likely mean a strong challenge to government policies that
favour unlimited global economic growth.
Nearly two billion
people live in water-stressed regions of the earth. Until now, the UN
has addressed this terrible reality with a program to give them access
to groundwater sources. But current levels of groundwater takings are
unsustainable. To truly realize the universal right to water, and to
protect water for nature's own uses, means a revolution in the way we
treat the world's finite water resources. There is no time to lose.
