3. Purpose
“To review knowledge of
climatic change and
variability, due to both natural
and anthropogenic causes...”
“To assess possible future
climatic changes and
variability and their
implications for human
activities.”
6. F. Kenneth Hare (1939 – 2002)
-Presented paper at WCC titled:
Climatic Variation and Variability:
Empirical Evidence from Meteorological
and Other Sources
- At the time this paper was presented,
Hare was a professor for the Institute
for Environmental Studies at the
University of Toronto, Canada
- Wanted to answer the questions:
1) “Is there evidence that climate can
and does change?”
2) “If so, what do past records and
present-day observations tell us
about such changes?”
3) “What is the nature of climatic
variation and variability?”
7. Hare’s Conclusions
-Human activities are affected by climate variability on both long and short-term
time scales.
- Regional climatic stress may not be abnormal but a product of climate
variability and it does not exclude short-term regional renewal.
- The northern hemisphere has been cooling and pollution may be offsetting the
cooling trend because of the heat it can trap in the atmosphere.
- Countries in northern latitudes will be more affected by changes in variable
surface temperature than countries in equatorial and southern latitudes.
- Variable precipitation is more likely to have a greater impact on “sub-humid or
semi-arid” regions.
- Economic practices that are aware of the possible return of regional climatic
stress are the best defence against their reoccurrence .
- In essence, climate is resilient.
8. Hare’s Follow-Up
- In 1980, Hare renewed his position in a published paper titled, The Planetary
Environment: Fragile or Sturdy?
- Hare writes, “The release of nearly one-third of the original soil carbon, and the
destruction of half the world’s original forest since Neolithic times have not
plunged us into a climatic convulsion. Somehow the natural systems that we
study have adapted to the changes, modulated them and masked them. They
may well keep up the good work – though they will now have to contend with
vastly more rapid environmental change.”
9. Ralph C. d’Arge’s Arguments
-In his paper, Climate and Economic Activity, d’Arge argues that a reduction of 1
degree Celsius in average temperature could cost the United States upwards of 7
billion dollars per year.
- In order to regulate CO2 emissions drastic changes in energy and deforestation
would be required.
- Although there have been proposals that the Earth is experiencing a warming
trend that could result in the possibility of greater rainfall, a possible cooling trend
cannot be ruled out entirely.
- There is no scientific evidence that CO2 emissions induce global climate change ;
but there is “significant indirect evidence “and “crude estimates.”
- Accurate evidence of effects cannot be reached for 10 – 20 years.
10. Conclusions of the World Climate Conference
-The increase of carbon dioxide in the lower atmosphere should be of urgent
concern to nations
- Dependency on the burning of fossil fuels and deforestation is seen as “likely to
result in a massive atmospheric CO2 increase in future decades and centuries;”
- These changes in CO2 levels may result in “possibly major long-term changes of
global climate;”
- Natural removal of CO2 from the atmosphere will be slow and so the impact of
its increase will last longer.
- Research should be increased in order to properly assess the impact of CO2 on
the climate and other areas.