Predictions of global climatic change
are becoming more confident. A broad consensus among the world's climatologists
is that there is now "a discernible human influence on global
climate."
Climate change is projected to raise sea
levels, threatening populations and ecosystems in coastal regions. Warmer
temperatures will lead to a more vigorous hydrologic cycle, increasing the
prospects for more intense rainfall, floods, or droughts in some regions. Human
health may be damaged by greater exposure to heat waves and droughts, and by
encroachment of tropical diseases to higher latitudes.
The developing world is especially
vulnerable to damage from climatic disruption because it is already under great
stress and has less capacity to adapt.
Climate Change: Linkages and Further
Damage
Destructive logging and deforestation
for agriculture continue to wreak havoc on the world's remaining tropical
forests. The burning of the Amazonian rain forests continues largely unabated.
Other forests in developed and developing nations are under heavy pressure.
Destruction of forests greatly amplifies soil erosion and water wastage, is a
major source of loss of species, and undermines the environment's natural
ability to store carbon. It releases additional carbon to the atmosphere,
thereby enhancing global warming.
Fossil-fueled energy use is climbing,
both in industrial nations and in the developing world, adding to atmospheric
carbon. Efforts to enhance energy conservation and improve efficiency are much
hindered by low energy costs and by perverse incentives that encourage waste.
Without firm commitments, most industrial nations will not meet the
carbon-emission goals they agreed to at the 1992 Rio conference. The transition
to renewable, non-fossil-carbon-based energy sources is feasible but is not in
sight for lack of aggressive political will. The insurance industry has
recognized the risks posed by climate change. Leading economists have identified
viable policies for reducing these risks. Markets undervalue ecosystems
worldwide and inflict few penalties against practices that do long-term
environmental and resource damage. Political leadership must introduce
incentives that reward sound practices.
Water Scarcity and Food Security
Humanity now uses over one-half of the
total accessible freshwater runoff. Freshwater is the scarcest resource in the
Middle East and in North Africa. Efforts to husband freshwater are not
succeeding there, in East Asia, or in the Pacific.
Global food production now appears to be
outpaced by growth in consumption and population. There is broad agreement that
food demand will double by 2030. Most land suitable for agriculture is already
in production. Sub-Saharan Africa's increase in agricultural production is
one-third less than its population growth. The region now produces 80 percent of
what it consumes, and per capita production is declining. Projections indicate
that demand for food in Asia will exceed the supply by 2010.
Thus, food consumption levels in many
countries are likely to remain totally inadequate for good nutrition. Widespread
undernutrition will persist unless extraordinary measures are taken to ensure
food for all, measures not now even contemplated by governments. Climate change
is likely to exacerbate these food problems by adversely affecting water
supplies, soil conditions, temperature tolerances, and growing seasons.
Destruction of Species
Climate change will accelerate the
appalling pace at which species are now being liquidated, especially in
vulnerable ecosystems. One-fourth of the known species of mammals are
threatened, and half of these may be gone within a decade. Possibly one-third of
all species may be lost before the end of the next century.
Biodiversity gives stability to the
ecosystems that we are so dependent on, enhances their productivity, and
provides an important source of new foods, medicines, and other products.
