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Human Contributions to Climate Change and Global Warming
Human industrial activities are believed to be adding to the amount of
"greenhouse gases" naturally present in the atmosphere. There
are mounting proofs that following the
industrial revolution of the 18th and 19th centuries, which commenced in
Britain and has expanded to several parts of the world, the amounts of of carbon dioxide, methane and other greenhouse gases in the
atmosphere has increased somewhat. this leaves room for the suspicion that
humans could have been contributing to Global Warming.
Based on scientific results and day-to-day physical
evidences, global warming is no longer in dispute. With the the verdict of
the fourth assessment report on climate change just released by the
Intergovernmental Panel on Climate Change (IPCC), there is also very little contention that
man contributes to the heating up of the Earth. However, the question that
remains is: how much of the warming is caused by man?
Human activities that lead to production of GHGs are:
Agriculture:
During
agricultural practices, methane gas (a GHG) is produced when bacteria
decomposes organic matter. It has been estimated that close to a quarter
of methane gas from human activities result from livestock and
the decomposition of animal manure. Paddy rice farming, land use and
wetland changes are also agricultural processes that could contribute to
the release of methane to the atmosphere. Use of fertilizers for
agricultural activities also lead to higherNO2 concentrations.
Deforestation: With the growth
of industrial activities has been worldwide deforestation. As part
of the photosynthetic process, trees abstract carbon dioxide from the air
and release oxygen back to the atmosphere. with deforestation, the number
of trees available to take in CO2 from the atmosphere has greatly reduced,
leading to more available CO2 and increased greenhouse effect. When forests are
cleared, most of the carbon in the burned or
decomposing trees escape back into the atmosphere
Fossil Fuels: Fossil fuels is
widely used to power our modern day engines and locomotives. The burning of coals, natural gas and oil yields most of
the energy used to produce electricity, heat houses, run automobiles and
power factories. The burning of fossil fuels to obtain energy to drive
these engines lead to production of tremendous amount of CO2 which is
released to our environment and increasers the concentration of CO2 in the
atmosphere. It is believed that CO2 generated from the burning of fossil
fuel accounts for about three-quarters of the total CO2 emissions from
human activities.
Refrigeration/Fire
Suppression/Manufacturing: Establishments and Industries used to use chlorofluorocarbons (CFCs) in
refrigeration systems, and CFCs and halons in
fire suppression systems and manufacturing processes.
Other human factors leading to
release of GHGs (particularly methane) to the atmosphere include pipeline
losses, landfill emissions and septic systems that enhance and target the
fermentation process also are major sources of atmospheric methane;
Indicators of the Influence of
Human Activities on Climate Change:
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