the global climate system, sustain an enormous diversity of plants and animals,
from minute phytoplankton to whales and act as an important sink for the
by-products of many human activities. Riparian and aquifer waters also have a
role in regulating the climate system, although their immediate benefit is on a
local or regional scale. At these scales they are important providers of water for
drinking, irrigation and industry. Riparian waters are also important for the
provision of food, and hydroelectric power.
Water is essential for human health, and yet for many of the world’s poorer
populations one of the greatest environmental threats to health remains a lack of
clean water and sanitation. A recent report estimated that more than half the
world’s population (some three billion people) live in squalor without access to
proper sanitation. One billion people have no access to safe water at all, an
important factor in the enormous global burden of diarrhoeal illness and early
childhood mortality, when approximately 5000 children die every day from
water-related illnesses.
Human activities are having adverse effects on these water stocks, which in
turn have adverse consequences for human health. Recent warming of the
oceans, presumably, at least in part, because of anthropogenic activities, can
have adverse consequences. Warmer oceans raise the sea level, affect the global
climate system, damage corals and alter the distribution of fishstocks
and behaviour of marine ecosystems. The overharvesting of marine species is
reducing the trophic level of the average marine harvest and many fisheries face
collapse.
Population growth, agricultural irrigation and industrial needs are placing
ever-greater demands on limited water resources. Approximately 40% of the
world’s population now face some level of water shortage, and underground
water reserves in many countries are being used faster than they are replenished.
On every continent, water tables are dropping — under the north China plain,
which produces nearly 40% of the Chinese grain harvest, the fall averages 1.5 m a
year. Regions under the most water pressure include China’s Yellow River basin,
the Middle East and the Aral Sea region of Central Asia.
—
Most of the water
from these sources is used for irrigation and industry rather than drinking. Unless
World Commission on Environment and Development, Our Common Future, Oxford University
Press, Oxford, 1987.
World Water Commission, A Water Secure World. Vision for Water, Life and the Environment, 2000.
S. Levitus, J. I. Antonov, T. P. Boyer and C. Stephens, Science, 2000, 287, 2225.
S.-Y. Hong and E. Kalnay, Nature, 2000, 408, 842.
R. H. Zhang, L. M. Rothstein and A. J. Busalacchi, Nature, 1998, 391, 879.
P. Pockley, Nature, 1999, 400, 98.
C. M. O’Brien, C. J. Fox, B. Planque and J. Casey, Nature, 2000, 404, 142.
E. Sanford, Science, 1999, 283, 2095.
D. Pauly, V. Christensen, J. Dalsgaard, R. Froese and F. Torres Jr., Science, 1998, 279, 860.
J. A. Hutchings, Nature, 2000, 406, 882.
L. R. Brown, Worldwatch Issue Alert, 2000, 1.
P. H. Gleick, Sci. Am., 2001, February, 28.
T. F. Homer-Dixon, Environment, Scarcity and Violence, Princeton University Press, 1999.
J. R. McNeill, in Something New Under the Sun. An Environmental History of the Twentieth-century
World, New York, 2000.
S. Postel, Sci. Am., 2001, February, 34.
Global Environmental Changes and Human Health
143
from minute phytoplankton to whales and act as an important sink for the
by-products of many human activities. Riparian and aquifer waters also have a
role in regulating the climate system, although their immediate benefit is on a
local or regional scale. At these scales they are important providers of water for
drinking, irrigation and industry. Riparian waters are also important for the
provision of food, and hydroelectric power.
Water is essential for human health, and yet for many of the world’s poorer
populations one of the greatest environmental threats to health remains a lack of
clean water and sanitation. A recent report estimated that more than half the
world’s population (some three billion people) live in squalor without access to
proper sanitation. One billion people have no access to safe water at all, an
important factor in the enormous global burden of diarrhoeal illness and early
childhood mortality, when approximately 5000 children die every day from
water-related illnesses.
Human activities are having adverse effects on these water stocks, which in
turn have adverse consequences for human health. Recent warming of the
oceans, presumably, at least in part, because of anthropogenic activities, can
have adverse consequences. Warmer oceans raise the sea level, affect the global
climate system, damage corals and alter the distribution of fishstocks
and behaviour of marine ecosystems. The overharvesting of marine species is
reducing the trophic level of the average marine harvest and many fisheries face
collapse.
Population growth, agricultural irrigation and industrial needs are placing
ever-greater demands on limited water resources. Approximately 40% of the
world’s population now face some level of water shortage, and underground
water reserves in many countries are being used faster than they are replenished.
On every continent, water tables are dropping — under the north China plain,
which produces nearly 40% of the Chinese grain harvest, the fall averages 1.5 m a
year. Regions under the most water pressure include China’s Yellow River basin,
the Middle East and the Aral Sea region of Central Asia.
—
Most of the water
from these sources is used for irrigation and industry rather than drinking. Unless
World Commission on Environment and Development, Our Common Future, Oxford University
Press, Oxford, 1987.
World Water Commission, A Water Secure World. Vision for Water, Life and the Environment, 2000.
S. Levitus, J. I. Antonov, T. P. Boyer and C. Stephens, Science, 2000, 287, 2225.
S.-Y. Hong and E. Kalnay, Nature, 2000, 408, 842.
R. H. Zhang, L. M. Rothstein and A. J. Busalacchi, Nature, 1998, 391, 879.
P. Pockley, Nature, 1999, 400, 98.
C. M. O’Brien, C. J. Fox, B. Planque and J. Casey, Nature, 2000, 404, 142.
E. Sanford, Science, 1999, 283, 2095.
D. Pauly, V. Christensen, J. Dalsgaard, R. Froese and F. Torres Jr., Science, 1998, 279, 860.
J. A. Hutchings, Nature, 2000, 406, 882.
L. R. Brown, Worldwatch Issue Alert, 2000, 1.
P. H. Gleick, Sci. Am., 2001, February, 28.
T. F. Homer-Dixon, Environment, Scarcity and Violence, Princeton University Press, 1999.
J. R. McNeill, in Something New Under the Sun. An Environmental History of the Twentieth-century
World, New York, 2000.
S. Postel, Sci. Am., 2001, February, 34.
Global Environmental Changes and Human Health
143