Greenhouse effect &Climate Change
The process through which heat is trapped near Earth's surface by greenhouse gases is called greenhouse effect . These gases are - carbon dioxide, methane, nitrogen oxides and CFCs.These gases allowed the sunlight to shine onto Earth's surface but trap 90% of the heat that reflects back to the atmosphere. Thus , these gases act as insulating glass walls of a greenhouse and keep the climate favorable for living beings by about 33° C.
Climate Scientists now agree that increase of greenhouse gases are directly linked to the increase of global temperature and affecting global climate.This is called climate change.
Greenhouse gas emissions increased 70% between 1970-2004 due to anthropogenic activities. Burning of fossil fuels to run power plants, vehicles,etc is responsible for the 80% increase of carbon dioxide in this timespan. Cutting of trees has accelerated the addition of this gas as carbon released from decaying plant material remained in the atmosphere as carbon dioxide due to the less absorption by photosynthesis.
Livestock farming, landfills,coal mining and natural gas processing is continuously adding methane to the atmosphere.
Nitrous oxides is added due to agricultural technologies and fossil fuels burning and has increased by 18% in the last 100 years .
CFCs are added due to the use of aerosol cans, airconditioners, refrigerators, etc.
Though water vapour is the most abundant greenhouse gas, it not considered as a direct cause of climate change because the warming ocean increases water vapour amount in the atmosphere.
Greenhouse gases and carbon dioxide equivalent: water vapour 0, methane 28, nitrous oxide 273 and Fluorinated gas 14,600.
Effects: Increase of greenhouse gases result into global warming which is responsible for the following:
Melting of ice caps in faster rate causing the rise of sea levels and ocean becomes less According to IPCC global sea level increases about 1.8 mm ( 0.07 inches) in each year from 1961 to 1993, and 3.1 mm (0.12 inches) per year since 1993. This will results into "climate refugees" in Bangladesh, the Netherlands and Florida of USA. Peoples of India, Bolivia,Peru, etc depend on glacial melt water for drinking, irrigation and hydroelectric power generation. Hence, melting of glaciers and ice caps will devastated these countries in coming days.
Greenhouse gase emmition has changed the global precipitation of rain and snow .It has been increased in the eastern parts of North and South America, northern Europe and northern and central Asia and decreased in parts of Africa, the Mediterranean and parts of southern Asia. As a result river runoff and ground water in some areas will increase and similarly will decrease in many dry regions.
Oceans warming up , so corals bleach and then die.Number of cases of flood, heat wave, cold snaps, storms,ect increases.Number of forest fire increases.
The Kyoto Protocol
It is an international agreement linked to the United Nations Framework Convention on Climate Change to reduce greenhouse gases for 37 industrial countries & European Union. The Protocol was adopted in Kyoto,Japan , in 1997 and became international law on 16th February, 2005.
192 nations commited to reduce their GHG emmition by an average of 5.2% by 2012, it is about 29% of world's total emissions.But the USA dropped it in 2001,as it is mandated only developed countries and it will hinder the US economy. In fact, in between 1990-2009 about 40% GHG emmition has increased globally.
COP / Conference of Parties:
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