Introduction
Climate change can be defined as a change in the state of climate that can be identified by changes in the mean and/or variability of its properties, and that persists for an extended period, typically decades or longer. It may be a consequence of natural internal processes or external influences. It can also defined as change of climate caused directly or indirectly due to human activities that alters the composition of the global atmosphere results in variations of natural climate observed over a comparable time period.
Climate change has been a consequence of increasing industrialization and the overuse of technology over the past 100 years. The rapid increase in population along with industrialization have bestowed heavily upon this phenomenon. It’s a diabolical and long-term problem, both in its impacts and remedies. Global warming has happened in the recent times and is evident from the rise in mean temperature of the earth’s atmosphere and surface.
It has led to many problems some of which are listed below :
- Rise in mean earth surface temperature, thus melting of polar caps and rising of sea level.
- Increase in temperature of earth’s atmosphere.
- Extinction of some animals.
- Summers are getting longer than winters.
- Introduction of new diseases.
Causes
The main cause of global warming is the emission of green house gases out of which the main gas is carbon dioxide (CO2) and the others like methane (CH4), nitrous oxide(N2O), water vapour (H2O) and ozone (O3) etc. Due to their excessive emission they trap heat in earth’s atmosphere, as a result the temperature of earth gets increased. The major source of carbon dioxide is the power plant emissions. In addition to this, there is a range of human made halo-carbons such as perflourocarbons (PFCs), hydroflurocarbons (HFCs), chloroflourocarbons (CFCs), etc. that are present in small amounts are potent and contribute significantly to the total warming.
The following list provides the natural and anthropogenic (related to humans) sources of these gases :
Carbon Dioxide
- Respiration from living organisms
- Volcanic eruptions
- Forest fires
- Decomposition of dead plants and animals
- Out gassing from the ocean
- Combustion of fossil fuels and cement manufacture
- Land use changes (deforestation and changing agricultural practices)
Methane
- Oceans
- Termites
- Natural wetlands
- Hydrates Fossil fuel mining
- Vegetation burning
- Waste treatment
- Rice cultivation
- Landfill
Nitrous oxide
- Processes in soils and oceans
- Oxidation of ammonia in the atmosphere Nitrogenous fertiliser use
- Biomass burning
- Management of livestock manure
- Fossil fuel combustion
- Industrial activities such as nylon manufacture
HFCs, PFCs and CFCs
- Present in small amounts in earth’s crust and gets released while volcanic eruptions
- Refrigeration
- Air conditioning
- Solvents
- Fire retardants
- Foam manufacture
- Aerosol propellants
- For PFCs, aluminium production
Tropospheric ozone
- Chemical reaction between other gases including CO2, CH4 and N2O.
- Industries, power generations and automobiles.