Loading ...
Sorry, an error occurred while loading the content.
 

The Earth's Life-Support System is in Peril

Expand Messages
  • npat1@juno.com
    Published on Tuesday, January 20, 2004 by the International Herald Tribune The Earth s Life-Support System is in Peril by Margot Wallström, Bert Bolin, Paul
    Message 1 of 1 , Jan 20, 2004
      Published on Tuesday, January 20, 2004 by the International Herald
      Tribune
      The Earth's Life-Support System is in Peril
      by Margot Wallstr�m, Bert Bolin, Paul Crutzen and Will Steffen

      Our planet is changing fast. In recent decades many environmental
      indicators have moved outside the range in which they have varied for the
      past half-million years. We are altering our life support system and
      potentially pushing the planet into a far less hospitable state.

      Such large-scale and long-term changes present major policy challenges.
      The Kyoto Protocol is important as an international framework for
      combating climate change, and yet its targets can only ever be a small
      first step. If we cannot develop policies to cope with the uncertainty,
      complexity and magnitude of global change, the consequences for society
      may be huge.

      We have made impressive progress in the last century. Major diseases have
      been eradicated and life expectancy and standards of living have
      increased for many. But the global population has tripled since 1930 to
      more than six billion and will continue to grow for several decades, and
      the global economy has increased more than 15-fold since 1950. This
      progress has had a wide-ranging impact on the environment. Our activities
      have begun to significantly affect the planet and how it functions.
      Atmospheric composition, land cover, marine ecosystems, coastal zones,
      freshwater systems and global biological diversity have all been
      substantially affected.

      Yet it is the magnitude and rate of human-driven change that are most
      alarming. For example, the human-driven increase in atmospheric carbon
      dioxide is nearly 100 parts per million and still growing - already equal
      to the entire range experienced between an ice age and a warm period such
      as the present. And this human-driven increase has occurred at least 10
      times faster than any natural increase in the last half-million years.

      Evidence of our influence extends far beyond atmospheric carbon dioxide
      levels and the well-documented increases in global mean temperature.
      During the 1990's, the average area of humid tropical forest cleared each
      year was equivalent to nearly half the area of England, and at current
      extinction rates we may well be on the way to the Earth's sixth great
      extinction event.

      The Earth is a well-connected system. Carbon dioxide emitted in one
      country is rapidly mixed throughout the atmosphere, and pollutants
      released into the ocean in one location are transported to distant parts
      of the planet. Local and regional emissions create global environmental
      problems.

      The impacts of global change are equally complex, as they combine with
      local and regional environmental stresses in unexpected ways. Coral
      reefs, for example, which were already under stress from fishing, tourism
      and agricultural pollutants, are now under additional pressure from
      changing carbonate chemistry in ocean surface waters, a result of the
      increase in atmospheric carbon dioxide.

      Similarly, the wildfires that hit southern Europe, western Canada,
      California and southeastern Australia last year were a result of many
      factors, including land management, ignition sources and extreme local
      weather. However, prevailing warm and dry conditions - probably linked to
      climate change - amplified fire intensity and extent.

      Poor access to fresh water means that more than two billion people
      currently live under what experts call "severe water stress." With
      population growth and economic expansion, this figure is expected to
      nearly double by 2025. Climate change would further exacerbate this
      situation.

      Biodiversity losses, currently driven by habitat destruction associated
      with land-cover change, will be further exacerbated by future climate
      change. Beyond 2050, rapid regional climate change, as would be caused by
      changes in ocean circulation in the North Atlantic, and irreversible
      changes, such as the melting of the Greenland ice sheet and the
      accompanying rise in sea levels of 6 meters, or 20 feet, could have huge
      economic and societal consequences.

      It is now clear that the Earth has entered the so-called Anthropocene Era
      - the geological era in which humans are a significant and sometimes
      dominating environmental force. Records from the geological past indicate
      that never before has the Earth experienced the current suite of
      simultaneous changes: we are sailing into planetary terra incognita.

      Global environmental change challenges the political decision-making
      process by its uncertainty, its complexity and its magnitudes and rates
      of change.

      Because of the uncertainties involved, decision-making will have to be
      based on risks that particular events will happen, or that possible
      scenarios will unfold. A lack of certainty does not justify inaction -
      the precautionary principle must be applied.

      Because of its complexity, global environmental change is often gradual
      until critical thresholds are passed, and then far more rapid change
      ensues, as seen in the growth of the ozone hole. Some rapid changes -
      such as the potential melting of the Greenland ice sheet - would also be
      irreversible in any meaningful human timescale, while other changes may
      be unstoppable, and indeed may have already been set in motion.

      Because of the magnitudes and rates of change, we are unsure of just how
      serious our interference with the dynamics of the Earth's system will
      prove to be, but we do know that there are significant risks of rapid and
      irreversible changes to which it would be very difficult to adapt.

      The first step toward meeting the challenge presented by global change is
      to appreciate the complex nature of the Earth's system, the ways in which
      we are affecting the system, and the economic and societal consequences.
      Scientists and policy-makers must establish a dialogue to communicate
      current knowledge and to guide future research.

      Real policy progress must address the need for large-scale change,
      technological advances and global cooperation. Incremental change will
      not prevent, or even significantly slow, climate change, water depletion,
      deforestation or biodiversity loss. Breakthroughs in technologies and
      natural resource management that will affect all economic sectors and the
      lifestyles of people are required.

      Although action at local, regional and national levels is important,
      international frameworks are essential for addressing global change. We
      must develop new approaches that consider the diversity of national
      circumstances and interests, based on a shared political will for action.
      Never before has an effective multilateral system been more necessary.

      The evidence of our impact on our own life-support system is growing
      rapidly. Will we accept the challenge to respond in a precautionary
      manner, or wait until a catastrophic, irreversible change is upon us?

      Margot Wallstr�m is the European Commissioner for the environment. Bert
      Bolin is the founding chair of the Intergovernmental Panel on Climate
      Change. Paul Crutzen was awarded the 1995 Nobel Prize in Chemistry. Will
      Steffen is executive director of the International Geosphere-Biosphere
      Program. This comment is based on "Global Change and the Earth System: A
      Planet Under Pressure," which looks at the findings of the International
      Geosphere-Biosphere Program.

      Copyright � 2004 the International Herald Tribune





      ________________________________________________________________
      The best thing to hit the internet in years - Juno SpeedBand!
      Surf the web up to FIVE TIMES FASTER!
      Only $14.95/ month - visit www.juno.com to sign up today!
    Your message has been successfully submitted and would be delivered to recipients shortly.