climate change & global warming consequenses
TRANSCRIPT
Global warming and Climate change
Prepared by: Veereshgouda. M. Police Patil
Contents
• What is global warming?• Science behind Global Climate Change • Green house effect• GHG’s concentration • Present and future trends in Global Climate Change • Sources of Green House Gases • Trends in Co2 emission • Consequences of global climate change: World and India
What is global warming?
Global warming: Regular increase in
mean annual temperature of the
earth.
This is mainly because of increase in
concentration of GHGs in the
atmosphere (especially CO2)
78% nitrogen
20.6% oxygen
< 1% argon
0.4% water vapor
0.036% carbon dioxide
traces gases:Ne, He, Kr, H, O3
Methane, Nitrous Oxide
Science behind global warming Green house effect
The green house gases - CO2 , methane, N2O, CFC, SF6, O3 (3-7%)
etc., absorb less of the insolation in atmosphere and much of the outgoing long wave radiations. Thus, they retain the heat in the atmosphere.
Results in
Uncomfortness
Diseases and deaths (Cancer, skin diseases etc)
The Green house gases (GHGs) provide a blanketing effect in the lower strata of the earth’s atmosphere, and this blanketing effect is being enhanced because of the human activities like burning of fossil fuels etc.
Greenhouse Effect & Global Warming
• The “greenhouse effect” & global warming are not the same thing. – Global warming refers to a rise in the temperature of the
surface of the earth. • An increase in the concentration of greenhouse gases leads to
an increase in the the magnitude of the greenhouse effect. (Called enhanced greenhouse effect) – This results in global warming.
Green House Gas Inventory
Carbon di-oxideCO2
Methane – CF4 Nitrous Oxide – N20
Perfluoromethane –CF4
Sulphur Hexafluoride – SF6
HCFC
CFC - 12
Emission trend of global green house gases
(www.unfccc.int)
Global warming potentials (GWP ) of Green House Gases
The main greenhouse gasesGreen house
gasesChemical formula
Pre-industrical
concentration
Conc. in 1994
Atm. life time
(years)
GWP
Carbon-dioxide
CO2 278000 ppb 358000 ppb Variable(Apprx.500)
1
Methane CH4 700 ppb 1721 ppb 12,2 +/- 3 21
Nitrous oxide N2O 275 ppb 311 ppb 120 310
CFC-12 CCL2F2 0 0503 ppb 102 6200- 7100
HCFC-22 CHCLF2 0 0105 ppb 121 1300 –1400
Tetrachlorofluoromethane
CF4 0 0070 ppb 50000 6500
Hexafluoride SF6 0 0032 ppb 32000 23900
UNITED NATIONS ENVIRONMENT PROGRAMME
320 ppb380
ppm
1775 ppb
520 ppb
250 ppb
GHG’s concentration in atmosphere
Global Carbon Dioxide (CO2) emissions from fossil-fuels 1900-2008
Global carbon emissions from fossil fuels have significantly increased since 1900. Emissions increased by over 16 times between 1900 and 2008 and by about 1.5 times between 1990 and 2008.
Sl. No.
GHG Concentration Remark
1 Atm. CO2 390.5 ppm 40% greater than in 1750.
2 Atm. nitrous oxide (N2O) 324.2 ppb increased by 20% since 1750.
3 Atm. methane (CH4) 1803.2 ppb 150% greater than before 1750.
4 Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs) and Sulphur hexafluoride (SF6)
------ increased relatively rapidly but their contributions to radiative forcing are less than 1% of the total by well-mixed GHGs
Present status of Direct GHG’s concentration (2011)
IPCC Assessment report 2013
Anthropogenic sources for GHG’s emissionGreenhouse gases Anthropogenic sources
Carbon-dioxide Fossil fuel combustionLand use conversion Cement production
Methane Fossil fuelsRice paddiesWaste dumps
Livestock
Nitrous oxide Fertiliser industrial processes combustion
CFC-12 Liquid coolants, FoamsHCFC-22 Liquid coolantsTetrachlorofluoromethane Production of aluminiumHexafluoride Dielectric fluid
Fossil fuel combustion Cement production
Land use conversion
Paddy field
Waste dumps
Livestock
Vehicular carbon emission
Global Greenhouse Gas Emissions by Source
1st
2nd
Land use change &
(www.unfccc.int)
Emission trend of global green house gases along regions
Highest carbon emitter(@ 1600 m MT of C/yr)
5th place, emits (@ 700 m MT of ‘C’/yr)
(www.unfccc.int)
2008 Global CO2 Emissions from Fossil Fuel Combustion and some Industrial Processes of top countries
Consequences of global warming
• Melting of polar region• Rise of sea level• Effect on agriculture• Human and animal Health
Impact of Global Warming on India• Unseasonal rains• Increasing Water Scarcity• Lower Wheat Yields• Increased incidence of heat waves• Shrinking of Himalayan Glaciers
Consequences…
Effect on natureEffect on societyEffect on glaciers Effect on agriculture and faunaEffect on forests
Consequences …
Effect on nature
In India 5 to 25% decline in winter rain fall, leading to
droughts during dry summer months
Increase in average summer monsoon rainfall over the
Indian subcontinent is only 10 to 15 per cent.
(Singh and Sonatakke,
2002)
Death of animals due to scarcity of water
Consequences contd…
Effect on society
Collapse of Maya civilization, (around 3000 years ago) on
Meso-America due to climate deterioration.
(Webster, 2002)
Collapse of Subir, (Around 300 AD agriculture civilization) of
Northern Mesopotamia in Syria.
(Weiss,
1993)
Consequences contd…
Indian Scenario
Almost all 335 glaciers in the Sutlej, Beas and Spiti river basins of Himachal pradesh are receding because of global warming.
(Sharma, 2001)
Overall prediction
By 2050, sea level throughout the world will rise by 21 cm.
(Anon, 1999)
Sea will rise by 18 cm in the year 2020 and 58 cm by the year 2090.
( Kumar, 2002)
Effect on glaciers
•Scary pictures of the northern polar regions in 1979 & 2005
•Polar ice has been decreasing by 1% per year since 1979.
1979 2005
Polar bear in struggle
Effect on Agriculture
Indian Scenario
At 0.5 o C increase in mean
temperature in Punjab,
Haryana and Uttar Pradesh
there would be a reduction in
productivity of wheat crop
by 10%.
(Samara and Sharma, 2002)
Overall prediction Decline in yield of crop in
Latin America, from Mexico to Argentina.
Predicted effects of climate change on agriculture by 2050
Climatic element Expected changes by 2050’s
Effects on agriculture
CO2 Increase from 360 ppm to 450 - 600 ppm
Good for crops: increased photosynthesis; reduced water use
Sea level rise Increased in south and offset in north by natural subsistence/rebound
Loss of land, coastal erosion, flooding, salinisation of groundwater
Temperature Rise by 1-2oC. Winters warming more than summers. Increased frequency of heat waves
Faster, shorter, earlier growing seasons, range moving north and to higher altitudes, heat stress risk, increased evapotranspiration
Precipitation Seasonal changes by ± 10% Impacts on drought risk' soil workability, water logging irrigation supply, transpiration
Storminess Increased wind speeds, especially in north. More intense rainfall events.
Lodging, soil erosion, reduced infiltration of rainfall
Source: Climate change and Agriculture, MAFF (2000)
Possible benefits and drawbacks of global warming on agriculture, based on an illustration in Scientific American, March, 1994
Consequences contd…
Indian Scenario
The Bengal tiger could
vanish
Effect on Fauna
Overall prediction
Central American Quetzal bird could disappear.
Other animals that could vanish around the world are Polar Bear, Penguins and the central African Mountain Gorilla.
(Anon, 2001)
Effect on fauna contd…
Polar bear
Penguin
Bengal tiger
American Quetzal bird African Mountain Gorilla
Consequences contd…
Effect on forests
Shift of species: 1oC rise in temperature will displace the limits
of tolerance of land species some 125 km towards the pole
or 150 m vertically on mountains.
(Anon, 1999)
Consequences contd…
Effect on insect-pest incidence:
Increase in temperature leads to:
• Accelerate to breeding population of insects resulting in more
generation per year
(Hedden, 1987)
Impacts of global warming on climate of India
• India is already a disaster prone area, with the statistics of 27 out of 35 states and Union territories being disaster prone, with most disasters being water related.
• According to surveys, in the year 2007-2008, India ranked the third highest in the world regarding the number of significant disasters, with 18 such events in one year, resulting in the death of 1103 people due to these catastrophes.
Catastrophes of climate change in India
• Floods• Droughts• Cyclones• Effects on the sea and coastal areas
Floods in India
• Approximately 40 million hectares of the land is vulnerable to floods, with 8 million hectares affected by it.
• A temperature increase of 2 °C in India is projected to displace seven million people, with a submersion of the major cities of India like Mumbai and Chennai.
Droughts
• Of the total agricultural land in India, about 68% is prone to drought of which 33% is chronically drought prone, receiving rainfall of less than 750mm per year.
• The World Record Of Drought Was In 2000 in Rajasthan, India.
Cyclones
• As a result of global warming, the average number of hurricanes per year has increased over the past 30 years.
• The notable cyclones in Indian history include the 1737 Calcutta cyclone and 1970 Bhola cyclone, which affected more than a million people.
Effects on the sea and coastal areas
• 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 4200 Km of road.
• The effects of global warming have also caused damage to coastal infrastructure, aquaculture and coastal tourism. The aquatic ecosystems such as mangroves, coral reefs and grass lands have also been affected by the climatic change.