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Global climate change

What is climate?

• Climate – average weather of an area over a long period – at least 30 years

• General weather conditions and seasonal variations

• The climate of the world is changed by - green house effect

Effect of Climate change

Winds and ocean currents are disturbed

Upsets hydrological cycle

Disturbs agriculture

Good! Bad!

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Green house gasesCAUSING GLOBAL

WARMING

Carbon dioxide (52%)Methane (18%)Chlorofluorocarbons (CFC’s) (24%)Nitrous oxide (6%)

Bad Effects of Global warming Land and ocean temperatures rise

North and south pole (Artic and Antarctic) Glaciers melt

Sea levels rise

Ocean currents change

Weather patterns change– Ecological disturbance– Reduction in biodiversity– Effect on Agriculture– Effect on human health

2007 Temperature Changes Compared to 1951-1980

-3 -2.5 -1.5 -1 -.5 -.1 .1 .5 1 1.5 2.5 3.4

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How Much is the Temperature Increase?

Some models propose up to 9°C increase this century

Two studies put the minimum at 1.5°C and maximum at 6.2°C

Another study puts the minimum at 2.5°C

1000800600400200

0-200-400-600

2003 2004 2005

Ice

Mas

s (k

m3 )

Year

Changes in Antarctica Ice Mass

Disasters in the making: Global warming effects to unfold faster as world inches towards 4 degree temperature rise

Warming could significantly exacerbate existing water scarcity in many regions

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Agriculture production would be hit because of temperature rise and floodingExtreme heat waves and drought on the rise due to melting ice

Wildlife is Effected• Polar Bears

– Require ice to live– Might eventually go extinct

• Sea turtles– Breed on the same islands as

their birth– Could go extinct as some islands

as beaches are flooded

• Other species may go extinct as rainfall patterns change throughout the world

• Polar Bears– Require ice to live– Might eventually go extinct

• Sea turtles– Breed on the same islands as

their birth– Could go extinct as some islands

as beaches are flooded

• Other species may go extinct as rainfall patterns change throughout the world

Effect on Humans• Sunstroke – many people will die

• Since more mosquitoes, snails and insects can grow (as more fish which eat them die due to increase in temperature of the water) –diseases like malaria will be on high

• Higher temperature and humidity increase sweating and cause skin diseases and Respiratory diseases

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Steps to Prevent Global Warming

• Plant more trees• Control population growth• Cut down rate of CFC’s and fossil fuels• Use non-conventional (renewable) sources of

energy• Shift from coal to natural gas• Reduce carbon dioxide from smoke• Adopt sustainable agriculture – grow heat

resistant crops

Kyoto Protocol• The Kyoto Protocol is an international agreement

linked to the United Nations Framework Convention on Climate Change (UNFCCC ) that aims at reduction of Green House Gases

• The Kyoto Protocol was adopted in Kyoto, Japan, on 11 December 1997 and entered into force on 16 February 2005

• 192 Parties (191 States and 1 regional economic integration organization) to the Kyoto Protocol to the UNFCCC

Kyoto Protocol• Cut emissions of not only carbon dioxide, but of also

other greenhouse gases, like, Methane (CH4), Nitrous oxide (N2O), Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs), and Sulphur hexafluoride (SF6)

• Reducing emissions of greenhouse gases by 5.2% below the emission levels of 1990. This goal is to be achieved by the year 2012

• Individual countries were assigned higher or lower targets and some countries were permitted increases

• During Kyoto protocol, allocation of carbon credits or Kyoto credits was made to different countries

• Each credit gives the owner the right to emit one metric tonne of carbon dioxide or other equivalent greenhouse gas

• If a country exceeds its emission quota, it has to pay for it in three possible mechanisms to get back the credits, and thus GHG emissions become expensive for the emitters

Carbon Credits

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• Mechanims I – Emission Trading: Countries that have not used up their quotas can sell their unused allowances as carbon credits, while others that are about to exceed their quotas can buy them.

• Mechanism II - Clean Development Mechanism: Developed countries (responsible for high GHG emissions, listed as Annex I countries) can start GHG reduction projects in relatively un-developed country (listed as non-annex countries).

• Mechanism III – Joint Implementation Mechanism: A developed country with relatively high cost of setting up of GHG reduction project, will set it in some other developed country. At present Russia and Ukraine are having highest number of JI projects.

Clean development mechanism

The actual value of each Carbon credit

may vary, subject to the market position.

Currently its value is about 12-20 Euros

Carbon Credits – Indian Scenario

• India has generated approximately 30 Million carbon credits and approximately 140 million in run, the second highest transacted volumes in the world.

• India’s carbon market is growing faster than even information technology, bio technology and BPOsectors as 850 projects with a huge investment of Rs 650,000 million are in pipeline.

• As per the Prime Minister's Council on Climate Change, the revenue from 200 projects is estimated at Rs. 97 billion till 2012.

What is Ozone? Ozone Layer?• Ozone (O3) is a highly-reactive form of oxygen.

• Ozone exists within both the tropospheric and stratospheric zones of the Earth’s atmosphere

• It is formed by the interaction of oxygen with UV radiation

• O2 + hn O* + O*• O* + O2 O3

• In the troposphere, ground level ozone is a major air pollutant and primary constituent of photochemical smog

• In the stratosphere, the ozone layer is an essential protector of life on earth as it absorbs harmful UV radiation before it reaches the earth

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Ozone layer depletion• Ozone is naturally found in stratosphere

which occurs 30 km above the ground level

• It has a normal thickness of 3mm

• In the past 4-5 decades a progressive decrease in ozone layer thickness is observed.

• It is more prominent over Antarctic region

• In fact a hole is formed in the ozone layer over the Antarctic region.

Ozone layer is being destroyed due to chemicals like

CFC: Chlorofluorocarbons:• CFC -11 is trichlorofluoromethane CCl3F• CFC-12 is dichlorodifluromethane, CCl2F2

• CFC-13 is chlorotrifluoromethane, CClF3

• There are others like, CFC-14, chlorotetrafluoroehtane

The reactions are…

• CFCl3 + hn CFCl2 + Cl*

• Cl* + O3 ClO + O2

• ClO + O3 Cl* +2O2

• These reactions are catalyzed by Br and I radicals also.

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CFC’s and ozone depletion• Chlorofluorocarbons are created

and used in refrigerators and air conditioners

• These chlorofluorocarbons are not harmful to humans and have been a benefit to us. Once released into the atmosphere, chlorofluorocarbons are bombarded and destroyed by ultraviolet rays

• In the process chlorine is released to destroy the ozone molecules

Facts about ozone depletion• A single chlorine keeps on destroying for two years before

it is converted to HCl or ClONO2

• Nitrogen oxides can trap the chlorine free radicals and stop ozone depletion

• All the CFCs are released in northern hemisphere, but Ozone layer depletion is more over Antarctic

• This is because of the so called Polar Stratospheric cloudsformed there in winters (-90oC)

• CFCs accumulate in these clouds in winter and in summer, when sunlight returns, form a platform for ozone depletion

Polar Stratospheric Clouds Effects of ozone layer depletion• UV radiation causes sunburns, skin cancer

• UV radiation absorbed by cornea in the eye leads to cataracts

• Loss of phyto and zooplankton in lakes and ponds

• phytoplankton in oceans reduces CO2 levels their decrease increases global warming

• Yields of food other crops reduced

• Greater evaporation of surface water

• Destroys fibres, paints and other materials

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• The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of substances believed to be responsible for ozone depletion

• Opened for signature on September 16, 1987, and entered into force on January 1, 1989, followed by a first meeting in Helsinki, May 1989- CFC emission should be cut by 35% by year 2000

• after hearing more bad news about seasonal thinning of ozone layer above Antarctica in 1989, it had undergone several revisions later, in 1990 (London), 1991 (Nairobi), 1992 (Copenhagen), 1993 (Bangkok), 1995 (Vienna), 1997 (Montreal), and 1999 (Beijing)

Montreal Protocol

• 36 countries signed the treaty first in 1987 • At present it has been ratified by 196 states • If the international agreement is adhered

to, the ozone layer is expected to recover to 1980 levels by 2050

• "perhaps the single most successful international agreement to date has been the Montreal Protocol" - Kofi Annan

Montreal Protocol

The largest Antarctic ozone hole recorded as of September 2006