Agriculture Reference
In-Depth Information
tation quantity (Kavikumar, 2010). Since climatic factors serve as direct
inputs to agriculture, any change in climatic factors is bound to have a
significant impact on crop yields. Many studies in the past have shown that
India is likely to witness one of the highest agricultural productivity losses
in the world in accordance with the climate change pattern observed. The
impact of climate change on Indian agriculture could result in problems
with food security and livelihood for the second most populated country
of the world.
19.2
CLIMATE CHANGE
Solar radiation is the main source of energy for life on earth, which arrives
mainly in the form of visible light. About 30 percent of the solar radiation
scattered back into space by the outer atmosphere, but the rest reaches to
the earth's surface, which reflects it in the form of a calmer, more slow-
moving type of energy called infrared radiation (this is the sort of heat
thrown off by an electric grill before the bars begin to grow red). Infrared
radiation is carried slowly aloft by air currents. Greenhouse gases (GHGs)
make up only about 1 percent of the atmosphere, but they act like a blanket
around the earth, or like the glass roof of a greenhouse which trap heat and
keep the planet some 30°C warmer than it would be otherwise
(Republics
of Maldives Climate Change, 2014). (The GHGs in the atmosphere act
as a thermostat for controlling the temperature on Earth's climate. The
atmosphere of the earth is under very complex state of energy equilibrium.
But rapid industrialization mainly during the second half of the twenti-
eth century has significantly increased concentration of green house gases
such as water vapor, carbon dioxide, ozone and methane in atmosphere
through indiscriminate burning of coal, oil, and natural gas which eventu-
ally trapped the escape of infrared radiation into space and cause increase
in atmospheric temperature. Farming activities like changes in land use,
application of nitrogenous fertilizers and methane emissions from agricul-
tural activities like ruminant animals and the cultivation of paddy has sig-
nificantly added methane and nitrous oxide in atmosphere. The increase
in atmospheric temperature of earth due to increase in concentration of
green house gases is technically termed as “enhanced greenhouse effect.”
Since 1970 to 2013 several key GHG emissions, including carbon dioxide
(CO
2
), methane (CH
4
), nitrous oxide (N
2
O), hydrofluorocarbons (HFCs),
