Agriculture Reference
In-Depth Information
Ghat). The CO
2
concentration has increased from a pre industrial value
of about 280 ppm to 393 ppm in 2010. Similarly, the global atmospheric
concentration of CH
4
and N
2
O as well as other important GHGs, has also
increased considerably.
1.2.2 TEMPERATURE
Average temperature on the earth surface has risen by 1.4°F over the past
century, and is projected to rise another 2 to 11.5°F over the next hundred
years. As per IPCC reports, temperature has shown an increase in 0.74°C
between 1906 and 2005 (IPCC, 2007a). Global average sea level rose at
an average rate of 1.8 mm per year over 1961 to 2003. There may be 0.5
to 1.2°C rise in temperature by 2020, 0.88 to 3.16°C by 2050 and 1.56 to
5.44°C by 2080 as projected by IPCC (IPCC, 2007b). Increase in global
temperatures has been accompanied by the changes in weather and cli-
mate. Increase in the temperature might be more during winter than mon-
soon season towards the end of the century. Similarly, seasonal maximum
temperature of Bihar, U.P. and Peninsular India likely to be increased.
Whereas minimum temperature supposed to be higher Bihar, Maharash-
tra, Rajasthan, U.P. and Peninsular India. High temperature induces high
evapo-transporation rate resulting in prolonged dry spell. Changes in tem-
perature increase the frequency of climate extremes, for example, heat and
cold waves.
1.2.3 WATER AVAILABILITY
It has been opined that the melting of ice glaciers, rise in sea water lev-
el, etc., will result in floods and cyclones, sea water intrusion into fresh
ground water, acceleration of coastal erosion, submergence of coastal and
island horticulture crops. On the other hand, a marginal increase, that is,
7-10% of annual rainfall in the subcontinent by 2080 has been projected.
Climate change has had an effect on the monsoons too. India is heavily
dependent on the monsoon to meet its agricultural and water needs, and
for protecting and propagating its rich biodiversity. Scientists at IIT, Del-
hi, have already noted subtle changes in the monsoon rain patterns. They
also warn that by the 2050s, India will experience a decline in its summer
rainfall, which accounts for almost 70% of the total annual rainfall that is
