Welcome

P.N.Harathi

TAD/14-05

Dept. Of Entomology

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a threat?

Is Global warming

Definition Global warming is defined as an increase in the average

temperature of the Earth's atmosphere, especially a sustained increase great enough to cause changes in the global climate’.

Green House effect The global warming potential (GWP) of a gas is defined

as the "radiative forcing" ( the additional radiative power that the gas is sending back to the ground) of a given quantity of gas, cumulated over a given period, generally 100 years.

This value is actually never given as an absolute figure, but relatively to CO2. The GWP of a gas is therefore "how much more" (or how much less) it "enhances the greenhouse effect over 100 years" (that is how much additional energy it sends back to the ground) compared to a similar quantity of CO2 emitted at the same time. 3

Current greenhouse gas concentrations

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GasPre-1750

troposphericconc.

Recenttropospheric

conc.

Absolute increase

since 1750

Percentageincrease

since 1750

Increasedradiative forcing(W/m2)

Carbon dioxide 

280 ppm 395.4 ppm 115.4 ppm 41.2% 1.88

Methane  700 ppb 1893 ppb 1193 ppb 170.4% 0.49

Nitrous oxide 

270 ppb326 ppb 56 ppb 20.7%

0.17

Tropospheric

ozone 

237 ppb 337 ppb 100 ppb 42% 0.4

Global Greenhouse Gas Emissions

Source: Intergovernmental Panel for Climate Change

Global Greenhouse Gas Emissions by source

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Important Green house gases How it’s produced Avg. Life Time

CO2 Burning of fossil fuels, solid waste, and trees and wood products. Changes in land use also play a role. Deforestation and soil degradation add carbon dioxide to the atmosphere, while forest regrowth takes it out of the atmosphere

100 years

CH4 Production and transport of coal, natural gas, and oil. livestock and agricultural practices and from the anaerobic decay of organic waste in municipal solid waste landfills.

12 Years

N2o Emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste.

114 years

CFCs A group of gases that includes hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride, among other chemicals. These gases are emitted from a variety of industrial processes and commercial and household uses, and do not occur naturally. Sometimes used as substitutes for ozone-depleting substances such as chlorofluorocarbons (CFCs).

A few weeks to thousands of years

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Global warming

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How Global Warming Works

Fossil fuels (coal, oil, natural gas)

Carbon Dioxide (CO2)

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Global warming

climatic events of the past 150 years have revealed that the temperatures have risen all over the globe, with the warming occurring in two phases. The first phase was from 1919 to 1940, with an average temperature gain of 0.35°C, and the second phase was from 1970 to the present, exhibiting temperature gains of 0.55°C.

Records show that the past 25 years have been the warmest time of the past 5 centuries.

Red colour: Severe Global warming

Blue colour: < Normal temperatures9

How is global warming measured?

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An Ice core is a core sample that is typically removed from an ice sheet, most commonly from the polar ice caps of Antarctica, Green land or from high mountain glaciers else where.

when entrapped carbon dioxide levels are high, the temperature goes up too.

Scientists use the ratio of heavy to normal water in ice layers to estimate average temperatures at the time the ice was made

ICE CORE DATA

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Ice core

12Ice at the South Pole contains air bubbles that are up to

800 000 years old.

Antarctic Ice-Core Stations

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CO2 Atmospheric Measurements

CO2 Measurements Since 1958 – Mauna Loa, Hawaii14

Argo float

15Deploying a robotic Argo ocean-profiling float.

Greed is the cause of global warming

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Burning of Fossil Fuels

Pollution from coal, natural gas, and oilPollution from coal, natural gas, and oilPollution from coal, natural gas, and oil 17

Effects of Global Warming

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What’s the proof that global warming is taking place?

THE TOP FLOODS IN INDIA’S HISTORY

Year Name Death People affected

1987 Bihar 1400 people 5000 animal dead

29 millon people

2005 Maharashtra 5000 people

2005 Gujarat < 123 (11 days) 2,50,000

2007 South Asian 2000 (> 15 days) 30 million

2009 K, Ke, Ori, G, NE

200 Million homes

2010 Ladakh 255 133 crores

2011 Indian Ker, WB, Bihar, Assam

> 10 million people

2012 Northern Indian

Assam 27 9 lakh people

Ut. K, H P and Jammu, resulting in landslides, cloud bursts and flash floods.

34 Hundreds

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People evacuated from their homes due to the incessant floods in India wade in the waters, searching for a place to

make camp during 2009

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Drought

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. This is particularly the states of Maharashtra, Gujarat, Rajasthan, Karnataka, Andhra Pradesh and Orissa. The World Record Of Drought Was In 2000 in Rajasthan, India. 22

Portage Glacier

1914 2004

• Alaska

Photos: NOAA Photo Collection and Gary Braasch – WorldViewOfGlobalWarming.org

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Colorado River

• Arizona

June 2002 Dec 2003

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Arctic sea ice melting away

This photograph shows the extent of sea ice in the summer of 1983.

Photo: NASA/Goddard Space Flight Center Scientific Visualisation Studio

Satellite photos show that by 2007 the extent of summer sea ice was greatly reduced

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Consequences of Global warming

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Its in our hands

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We are running out of time

Act now before its too late

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What’s being done now to reduce our emissions?

Solar Power Wind Power Fuel-Efficiency 30

Simple Things To Do

Turn off your computer or the TV when you’re not using it.

Take shorter showers. Heating water uses energy.

Keep rooms cool by closing the blinds, shades, or curtains.

Turn off the lights when you leave a room.

Use compact fluorescent bulbs.

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Simple Things To Do

Dress lightly when it’s hot. Instead of turning up

the air conditioning, use a fan.

Dress warmly when it’s cold instead of turning up the heat.

Offer to help your parents keep the air filters on

your AC and furnace clean.

Walk short distances instead of asking for a ride in the car.

Plant a tree. Recycle.32

Each one Plant one

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Thank you34