Climate change and

Water resources

Changes are being seen around the world

Upsala glacier, Patagonia

1928

2004

Source: Greenpeace

Pederson Glacier (Alaska)

Larsen B ice shelf, West Antarctica

Source: NASA

3250 square km of ice 220 m thick broke off3250 square km of ice 220 m thick broke off

Sea levels are rising

Source: http://www.flickr.com/photos/go_greener_oz/3047060508/

Source: Greenpeace

Drought in Amazon river, 2005

All is not well

Why is this happening?

Source: Vital Climate Graphics, Grid Arendal / UNEP

Gases like carbon dioxide are essential for life on Earth.

They trap some of the heat (infra-red radiations) leaving the Earth. Without them, Earth’s average temperature would be -200 C

They are called

Green House Gases

(GHGs)

Source: IPCC (2007)

Some are natural

some man-made

The Earth has natural systems that heat it and other natural systems that act as cooling factors. Thus an equilibrium is maintained.

But there is an imbalance being created and the factors that heat the Earth are becoming more prominent.

Atmospheric CO2 has increased from a pre-industrial concentration of about 280 ppmv to about 367 ppmv at present

Methane and nitrous oxide fare no better

To learn more about the concentration of GHGs in the atmosphere before the era of instruments and measurements, scientists are analyzing gases trapped in ice

And we find that…….

The concentrations of greenhouse gases that we are seeing now, has not been witnessed in the past

600000 years

Source: IPCC (2007)

We’re blanketing the Earth with more and more of these gases and the ‘ball is going warm’

Source: http://www.flickr.com/photos/perryham/3577638548/

14

13.2

14.8

Eleven of the last twelve years were the warmest since thermometer records began in 1850

A hot future awaits us

Global mean surface temperature could rise between 1 - 4.5 0C by 2100

What is increasing GHGs?

Forests are becoming croplands to feed our growing millions.

Fewer trees, more carbon dioxide in the atmosphere

Intensification of agriculture to feed the growing millions

Source: IGBP

Global fertilizer consumption

More nitrous oxide released

Source: http://maps.grida.no/go/graphic/the-richer-we-get-the-more-we-discard-human-consumption-waste-and-living-standards

Philippe Rekacewicz, UNEP/GRID-Arendal

Changing lifestyles

More methane generated by anaerobic decomposition of wastes in landfills

Changing lifestyles

http://www.flickr.com/photos/lingaraj/2415084235/

Increasing industrialization to meet our growing demands

Increased demand for electricity

From domestic consumersFrom industriesFrom the agriculture sector

Electricity generation

Source: International Energy Agency

0.82 kg of CO2 produced for every unit of electricity generated from coal.

That’s approx. 1 kg of CO2 produced for every unit of electricity we use.

Energy use

Source: CDIAC

What changes do scientists predict?

By the end of the century…

• Global mean surface temperature could increase by 1.0 to 4.5 0 C (best estimates)

• Global mean sea level could rise by 0.18 – 0.59 m

How will this affect our water resources

Precipitation patterns will change

There may be more intense rainfall on rainy days, resulting in floods

and more dry days in a year, causing drought

Damages due to floods has cost India

over Rs 800 crore every year

350 million Indians have been

affected badly due to drought in past ten years

Groundwater – it’s finite!

78% of assessed groundwater units in Delhi are over-exploited

(extraction > recharge)

India will reach a state of water stress before 2025

Sea level will be a minimum of 40 cm higher than today by

the end of 21st century

Source: TERI 1996

11 % of Bangladesh's coastal land is likely go underwater, creating 7 to 10 million climate refugees

What is the impact of a rise in sea levels?

Islands at low levels, such as Lakshadweep, can be flooded.Islands at low levels, such as Lakshadweep, can be flooded.

Entire ecosystems, such as the mangroves, can be wiped out.

Entire ecosystems, such as the mangroves, can be wiped out.

This image shows the change in pH of the oceans over the past 300 years. The brighter the color, the more the decrease in pH.

http://upload.wikimedia.org/wikipedia/commons/7/76/Blue_Linckia_Starfish.JPG

The solution is in our hands

We can do many things

• Electricity

• Water

• Green buildings

• Transport

• Renewable energy

• Afforestation

• Spread awareness

Acknowledgements

Ms Ulka KelkarMs Neha Rathi