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- Permanent Link:
- http://dpanther.fiu.edu/dpService/dpPurlService/purl/FI15042684/00001
Notes
- Scope and Content:
- The climate of our planet is changing. The climate has always been variable, but today there
is a growing concern over climate change issues, perhaps because the magnitude of the
change seems to be unprecedented but, more importantly, because there is strong
evidence to suggest that humanity might be directly responsible for climate change.
Any change in climate would lead to destabilization of environmental and social conditions
all around the globe. These disturbances could jeopardize the conservation of natural
ecosystems and sustainability of socioeconomic systems. Consequently, climate change will
also adversely affect, and indeed is already affecting, the conservation of World Heritage
properties, both natural and cultural. Heritage is an irreplaceable source of life and inspiration,
it is humankind’s legacy from the past, with which we live in the present and pass on
to future generations.
Our planet is kept warm due to the socalled
greenhouse effect. This effect consists
of trapping the energy – radiated by
the earth into the atmosphere – instead of
allowing it to escape into outer space. The
greenhouse gases involved in this regulatory
mechanism are usually found in the
atmosphere at very low concentrations.
Carbon dioxide (CO2) molecules are never
found at concentrations higher than a
few hundred parts per million (ppm) of air
parcels. Nevertheless they play a critical
role in the climatic equilibrium of the
planet. Prior to the Industrial Revolution,
CO2 concentration was 280 ± 10 ppm for
several thousand years. But the present
atmospheric CO2 concentration is above
360 ppm and such a level has never been
reached over the past 420,000 years.1,2
Changing CO2 concentrations in the atmosphere will undoubtedly have an impact on the
climate system, but the processes involved are multiple, complex, and feedback on one
another. Extensive research is being carried out worldwide to understand better our impact on the changing climate of planet Earth. The Intergovernmental Panel on Climate Change
(IPCC) was established under the auspices of the World Meteorological Organization (WMO)
and the United Nations Environment Programme (UNEP) to assess, compile and synthesize
scientific, technical and socio-economic information relevant to our comprehension of
climate change, its potential impacts, and outline options for adaptation and mitigation. The
periodic Assessment Reports of the IPCC constitute the best synthesis of the state of our
knowledge of climate change.
According to the IPCC, global average temperature increase has reached 0.6 ± 0.2 °C over
the twentieth century.3 There has been a widespread retreat of mountain glaciers in non-
Polar Regions. Northern Hemisphere spring and summer sea-ice extent has decreased by
about 10% to 15% since the 1950s. The global ocean heat content has increased since the
late 1950s and the global average sea level rose by at least 0.1 m during the twentieth century.
The IPCC also develops possible scenarios for anthropogenic emissions in order to project
future climate trends. Depending on these scenarios, climate models project that by 2100
atmospheric CO2 concentrations will reach 540 to 970 ppm. The global average surface
temperature is projected to increase by 1.4 °C to 5.8 °C over the period 1990 to 2100.4
Global mean sea level is projected to rise by 0.09 m to 0.88 m between 1990 and 2100.5
Global average water vapour concentration and precipitation are projected to increase
during the twenty-first century, and larger year-to-year variations in precipitation are very
likely over most areas where an increase in mean precipitation is projected. Changes in
extreme and/or severe weather events such as heat waves, droughts, extreme precipitations,
severe tropical cyclones, can also be expected.
Record Information
- Source Institution:
- Florida International University
- Rights Management:
- Please contact the owning institution for licensing and permissions. It is the user's responsibility to ensure use does not violate any third party rights.
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