12-14 September, 2011, Lucknow - Earth Science India

National Conference on Science of Climate Change and Earth’s Sustainability: Issues and Challenges ‘A Scientist-People Partnership’
12-14 September, 2011, Lucknow
IMPACT OF INTRUSION OF OZONE FROM THE
STRATOSPHERE ON THE TROPOSPHERIC OZONE
LEVELS IN INDIA
Nandita D. Ganguly 1 and Chris Tzanis 2
1 Department of Physics, St. Xavier’s College, Ahmedabad-380009, Gujarat
2 Department of Energy Technology, Technological Educational Institute of Athens, Greece
Decrease in stratospheric ozone will result in an amplification of the solar
ultraviolet B radiation reaching the ground, which is a threat to the human society. On
the other hand, ozone being toxic to the living system and an important contributor to
anthropogenic global warming, high levels of tropospheric ozone will have adverse
effects on the air quality and climate. Transport of ozone from the stratosphere to the
troposphere will cause stratospheric ozone to decrease and tropospheric ozone to
increase, which can in turn have serious consequences for life on earth. Stratosphere-
Troposphere Exchange (STE) is regarded as an important factor controlling the budget
of ozone in the troposphere and lower stratosphere. Study of STE events in India are so
far restricted to coordinated campaigns and measurements over longer periods are
relatively scarce. The surface ozone levels in some Indian cities have increased
significantly in the recent years. In the light of these observations, the paper is aimed to
identify the Indian latitudes, which are most likely to be affected by STE, the frequency
of occurrence of shallow and deep STE events and the depth up to which stratospheric
ozone descends into the troposphere during these events over the period of 24 years. In
addition, the contribution of STE events to the observed high surface ozone levels for a
number of cities covering north to south of India will be presented.
CLIMATE CHANGE AND MONSOONAL RAIN-
PRODUCING WEATHER SYSTEMS ACROSS INDIA
Nityanand Singh 1 , H.N. Singh 1 and Ashwini A. Ranade 2
1 Indian Institute of Tropical Meteorology, Pune
2 National Centre for Medium Range Weather Forecasting, New Delhi
email: nsingh@tropmet.res.in
Attempts have been made to understand relationship amongst global warmingcooling,
Asian-Indian summer monsoon circulation intensity, El Niño-La Niña in the
equatorial central and eastern Pacific Ocean and rainfall across India. During warmer
134