CLIMATE CHANGE: AN OVER VIEW
What is ‘climate change’?
Climate change is a shift in ‘climate’ relative to a given reference time period
•
It is caused by:
Natural factors
-
Solar variability
-
Volcanic dust levels
-
Internal variability
-
Geological change
Human factors
Greenhouse gases
•
-
Aerosols
-
Ozone depletion
-
Land use change
Global atmospheric concentration of carbon dioxide has increased from a
pre-industrial value of about 280 ppm to 379 ppm in 2005. This exceeds by
far the natural range over the last 650,000 years (180 to 300 ppm) as
determined from ice cores.
•
The annual carbon dioxide concentration growth-rate of 1.9 ppm per year
during the 10 year period 1995 – 2005 was larger than it has been since the
beginning of continuous direct atmospheric measurements (1960 – 2005
average: 1.4 ppm per year).
•
Annual fossil carbon dioxide emissions increased from an average of 6.4 GtC
per year in the 1990s, to 7.2 GtC per year in 2000–2005.
•
Exhaust trails from a commercial airliner. Carbon dioxide is the principle
GHG emission from aircraft, however, planes also release water vapour and
nitrous oxide.
•
It is estimated that the world’s 16 000 commercial jet aircraft produce 600
million metric tons of carbon dioxide per year, nearly equal to the amount
produced by all human activities in Africa per year.
Carbon Footprint by Marine Fishing Boats
•
Estimates indicate that fossil fuel consumption by marine fishing boats is
around 1842 million liters per year.
•
CO2 emission by marine fishing sector is 4.85 million tonnes per year.
•
One tonne of marine fish catch produces 1.72 t of CO2.
•
Trawlers account for 51% of the catch, but 70% of CO2 emission.
2007 Warmest Year
•
Figure shows 2007 temperature anomalies relative to the 1951-1980 base
period mean.
•
The global mean temperature anomaly, 0.57°C (about 1°F) warmer than
the 1951-1980 mean, continues the strong warming trend of the past
thirty years that has been confidently attributed to the effect of increasing
human-made greenhouse gases (GHGs) (Hansen et al. 2007).
•
The eight warmest years in the GISS record have all occurred since 1998,
and the 14 warmest years in the record have all occurred since 1990.
Evidences of climate change
 Duration of ice cover on rivers and lakes has decreased by 2.5 weeks
over the last century in mid- & high latitude areas
 Arctic sea ice loss in area (10 - 15%) and thickness (40%) over the last
half century.
 Decline in snow cover (10%) for N hemisphere since 1960
 World-wide retreat in alpine glaciers over last century
 Widespread changes in permafrost
An ice free Arctic?
•
Arctic sea ice cover, 1979. Between 1979 and 2003 (Figure 8b), Arctic
perennial sea ice has been decreasing at a rate of 9% per decade.
•
map of sea ice extent for October 16, 2007; the magenta line shows the
median October monthly extent based on data from 1979 to 2000.
Melting Glaciers On Indian Soil
Extreme Events
•
2002 drought
•
20 day heat wave during May 2003 in Andhra Pradesh
•
Extreme cold winter in the year 2002-03
•
Drought like situation in India in July 2004
•
Abnormal temperatures during March 2004 and Jan 2005
•
Floods in 2005
•
Cold wave 2005 - 06
•
Floods in arid Rajasthan & AP and drought in NE regions in 2006
•
Abnormal temperatures during 3rd week of Jan to 1st week of Feb 2007
Heat Wave (2003) - Damage to Poultry
Andhra Pradesh
¤
20 lakhs birds died in May & June 2003
¤
Highest in E. Godavari-7 Lakhs; W. Godavari – 5 lakhs
¤
Egg production decreased in the state by 25%
¤
Total Loss by 27 Crores
Increased risk of floods, potentially displacing tens of millions of people, due to
sea level rise and heavy rainfall events, especially in Small Island States and lowlying
deltaic
areas
Bangladesh is projected to lose about 17% of its land area with a sea level rise of
one meter - very difficult to adapt due to lack of adaptive capacity
One of the most serious implications of Climate Change is the increase in
Extreme Weather Events
Climate change has no boundaries, affecting the world's population
Developing
countries
are
the
most vulnerable to climate change
•
Impacts are worse - already more flood and drought prone and a large
share of the economy is in climate sensitive sectors
•
Lower capacity to adapt because of a lack of financial, institutional and
technological capacity and access to knowledge
•
Climate change is likely to impact disproportionately upon the
poorest
countries
and
the
poorest
persons
within
countries,
exacerbating inequities in health status and access to adequate food, clean
water and other resources.
CLIMATE PREDICTION
Disappearing Climates
•
IPCC scenarios to project changes under possible temperature increases. If
average
global temperatures increase 3.4° C by 2100, existing climates
could disappear over 10-48 per cent of the Earth’s land surface.
•
Some temperate climates, concentrated in tropical
mountains and the
high latitudes of continents, may disappear altogether.
Impacts of Climate Change on Various Sectors in India
•
Warming of the climate system is unequivocal and is evident from the
observations of increase in air temperature, melting of snow from snow
clad mountains and rising global mean sea level.
•
These changes have profound influence on various sectors, viz., water
resources, agriculture, land use, coastal ecosystem, livestock and fisheries
in many ways.
Agriculture
•
Eastern region in the country is predicted to be most affected by increased
air temperature.
•
Major shifts in cropping pattern are expected to take place and the area
under rabi crops are likely to be reduced and may move towards north.
•
Reduction in crop yields is more likely in the rainfed areas due to changes
in rainfall pattern during monsoon season.
•
Although, increased levels of Co2 may increase net primary productivity of
plants, the changes in temperature associated with the above phenomena
may nullify the benefit.
•
Potential yields of major cereals crops are likely to be reduced due to likely
increase in temperature.
•
Major pulses pigeonpea in kharif and chickpea in rabi sorghum are to be
decreased.
•
The impact of warming scenarios becomes apparent at higher levels of
fertilizer application from 2030 onwards.
•
In future, therefore, much higher levels of fertilizer may need to be applied
to meet the increasing demand for food.
•
The production of fruits may be significantly affected if the changes in
climate happen to coincide with the critical periods. Global warming will
push the snow line higher and dense vegetation will shift upwards. This
shift will be selective and species specific due to the differential response of
plants to changing environmental conditions.
•
The nutritional quality of cereals and pulses may also be moderately
affected which, in turn, will have consequences for our nutritional
security.
•
The loss in farm-level net revenue may range between 9 per cent and 25
per cent for a temperature rise of 2-3.5°C.
Crop-Pest Interactions
•
The change in climate may bring about changes in population dynamics,
growth and distribution of insects and pests.
•
Changes in rainfall, temperature and wind speed pattern may influence
the migratory behaviour of the locust.
•
Most crops have C3 photosynthesis (responsive to C02), while many weeds
are C4 plants (non-responsive to CO2). The climate change characterized
by higher CO2 concentration will favour crop growth over weeds.
Irrigation Water Availability
Glaciers in the Himalayan mountain ranges will retreat further, as
•
temperatures increase: they have already retreated by 67% in the last
decade. Glacial melt would lead to increased summer river flow and floods
over the next few decades, followed by a serious reduction in flows thereafter.
The projected climate change will disturb the water balance in different parts
•
of India and the quality of groundwater along the coastal track will be more
affected.
Increase in projected extreme rainfall events in major river basin of Ganga,
•
Godavari, Krishna, Mahanadi, Brahmani, has not shown increased runoff for
all the above basins perhaps due to increase in evapotranspiration on
account of increased temperature.
The surface water availability in Ganga, Godavari and Krishna showed a
•
general increase
Climate-related Coastal Hazards— Future Scenario
•
The past observations on the mean sea level along the Indian coast show a
long-term rising trend of about 1.0 mm/year.
•
However, the recent data suggests a rising trend of 2.5 mm/year in the sea
level along Indian coastline.
•
The increase in sea surface temperature corresponding thermal expansion,
related sea-level rise is expected to be between 15 cm and 38cm by the
middle of this century and between 46 cm and 59 cm by the end of the
century.
•
A one-meter sea level rise is projected to displace approximately 7.1 million
people in India, and about 5,764 km2 of land area will be lost, along with
4,200 km of roads.
•
An increase in the frequency of severe cyclonic storms is likely under the
climate change scenario; this may enhance the vulnerability of those
districts that are already ranked as vulnerable under the current climate
scenario.
Fisheries and Aquaculture
•
Impacts would affect the capture, production and marketing costs, loss of
infrastructure fishing tools and housing.
•
Migration of different marine species to favourable climate regions.
•
In general temperature changes are likely to impact cool water species
negatively, warm water species positively.
Strategies for combating climate change
Conservation Strategies
Alternate Fuels (bio-fuels)
Some wild ideas
Another approach involves a completely artificial CO2 collector that emulates the
sequestration capability of photosynthesizing trees. Based on technology used in
fish tank filters and developed by scientists from Columbia University’s Earth
Institute, this method, called ‘air capture’ would remove CO2 directly from the
atmosphere. Its advantage over the carbon capture and storage technologies
currently in development is that it can collect the CO2 at the location of the ideal
geological deposits for storage.
•
The Government of Iceland and the Earth Institute have high hopes for
matching air capture and geological sequestration in basalts. Whether this
scheme becomes a viable contribution in solving the climate crisis will
depend on the success of ongoing experiments and the financial support it
receives, as well as the regulatory constraints involved.
•
Sources: Lackner 2003, Lackner and Sachs 2005, IMO 2007, Morton 2007
•
Sino-Italian ecological and energy-ef.cient building at Tsinghua University,
Beijing
•
A new state-of-the-art building on the campus of Tsinghua University in
Beijing will serve as the University’s education, training, and research
centre for environmental protection and energy conservation. The facility
maximizes solar capabilities by utilizing both passive and active strategies,
including 1 000 square metres of photovoltaic panels.
•
The panels are integrated into the structural design of the building in a
manner that effectively captures energy while providing shade for the
structure’s terraces. The University and the architects who conceptualized
the structure hope the building will also serve to educate and emphasize
innovative possibilities for energy-efficient building, particularly in regard
to CO 2 emissions.
•
Source: © D. Domenicali/ ddphoto.it courtesy of MCA
•
Essentially, exhaust gas from the power plant is bubbled through
cylindrical upright tanks full of algae-laden water.
•
The algae extract the CO2 from the exhaust and convert it to sugars via
photosynthesis. Via further metabolism these sugars are then converted to
oils and proteins.
•
Portions of the algal soup are continually removed and dried into algae
cakes (yummm!!). The cakes are then repeatedly washed with solvents to
extract the ‘algal oil’.
•
This oil is then converted to biodiesel via transesterification and the
remaining biomass is treated with enzymes, thereby converting starches
into simple sugars. Ethanol can then be produced via the fermentation of
these simple sugars.
At the heart of the technology is a plastic cylinder full of algae, which literally
sucks the CO2 out of a power plant's exhaust. The algae can in turn be converted
into biofuel
Adaptation and Mitigation Strategies in Agricultural Production to Cope up
Climate Change
•
Altered agronomy of crops
•
Development of resource conserving technologies such as surface seeding
on zero tillage in upland crops
•
Increasing income from agricultural enterprises
•
Improved land use and natural resources management policy and
institutions
•
Organic farming
•
Rainwater harvesting and groundwater recharging
•
Drought management techniques
•
Improved risk management through early warning systems and crop
insurance
Mitigation Options for GHG in Agriculture
 To increase the soil carbon, organic manures, minimal tillage and residue
management should be encouraged
 Changing land use by increasing area under horticulture and agroforestry
 Improving the energy use efficiency in agriculture by using better designed
machinery
 Improved management of rice paddies both for water and fertilizer use
efficiency
 Use of nitrification inhibitors and fertilizer placement practices need
further consideration
 Improved management of livestock population
EPILOGUE
•
Global Warming is now a reality.
•
Despite uncertainties, climate change is more or less evident in terms of
increasing extreme weather events and large climate variability
•
Future projections are quite alarming and pose greater threat to
developing countries in terms of increased frequencies in Extreme Events.
•
This could bring greater challenges for managing future climate.
***