8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 1/16

Climate Change and the Himalayas

Presentation at Rivers for Life 3

Shripad Dharmadhikary

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 2/16

Based on Study Done forInternational Rivers

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 3/16

Himalayas Mountain ranges that separate the Indian

sub-continent from the Tibetan plateau

An arc 2,400 km long

Across Pakistan, India, Nepal, Bhutan

Often Called the Third Pole

Source of Ganga, Indus, Brahamaputra A Global Heritage

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 4/16

Massive Dam Building Plans Vast Store of Water 

High Slopes, Fast moving rivers

High Hydropower Potential

Plans for over 80,000 MW capacity in

the next 10 years

Himalayas could be the area withhighest concentration of dams in the

world

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 5/16

Hydropower PotentialTotal Claimed

Potential

(MW)

Capacity Already

Developed

(MW)

% Capacity

Remaining

to be

Developed

Bhutan 23,760 1,488 93.74%

 Nepal 44,000 561 98.73%

Pakistan 41,722 6,444 84.55%

India

(Himalayan)

118,210 26,376 77.69%

India (Rest) 30,491 19,641 35.58%

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 6/16

Hydropower Projects

Existing Under 

Construction

Proposed

 Nepal 545

(15 )

84

(2)

26,324

(37)

Pakistan 6,385

(6)

1,405

(7)

33,769

(35)

Bhutan 1,480(5)

15,693(16)

India 15,208

(74)

17,765

(37)

93,615

(318)

In MW (Number of Projects in brackets)

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 7/16

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 8/16

Climate Change Huge impact on Himalayas ± warming

higher in Himalayas than global average

Will alter the fundamental assumptionsof dam building program - water flow inthe rivers

Impacts not considered in dam building

Many Himalayan rivers have significantflow generated from glacial and snowmelt - 70% of the summer flow of themain Ganga, Indus and Kabul

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 9/16

I

mpacts in Himalayas Many uncertainties but broad impacts

clear 

Increased in extreme events

Leading to flash floods, landslides,

debris flow

Increased variability in river flows

Much lower lean season flows, lower 

total flows

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 10/16

Increased Glacial

Melting Glaciers melting is accelerating

Glacial melt will lead to initial increase in river flows - raising concerns of safety of the dam,

increased flooding and submergence

Subsequent depletion or disappearance of glaciers will lead to much lower flows,especially lean season flows - impacting

 performance

Massive negative downstream impactsespecially in lean season with several hundredmillion people potentially affected in the plainsof Ganga, Indus, Brahmaputra

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 11/16

Increased Threats of 

GLOF Increased threats of Glacial Lake Outburst

Floods (GLOF)

As Glaciers melt, they can form lakes behindtemporary dams of ice and moraine

Flash floods result when these dams fail

Climate change will increase the threat of 

GLOF Increase in frequency of GLOFs already

seen in Nepal and Bhutan

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 12/16

Increased

Sedimentation Increased silt loads in rivers due to

higher proportion of precipitation falling as

rain rather than snow, with higher erosion Increase in extreme events and intensities of 

 precipitation

Melting of permafrost

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 13/16

Country Specific

impacts  Nepal, Bhutan, India, Pakistan

Increased frequency of GLOFs can threatendams, population centres

Increased flow can threaten proposedhydropower dams

Pakistan ± increased flow in Indus basin canexacerbate the problem of flooding

Pakistan ± later, dramatic decline in flows«conceivable by a ³terrifying´ 30-40%

India ± fall in lean season flow can threatenmillions of people in the Ganga-Brahmaputra

 plains

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 14/16

High Level of 

Uncertainty Large gaps in knowledge of short and

long term impacts

Impacts of water flow, safety, hazards

Downstream impacts

 Need to allow flexibility in planning to

take care of knowledge gap

Large dams will lock huge levels of 

resources, block other options

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 15/16

Large Dams Dangerous

Solutions As climate change increases variability

in river flow, large storage dams

suggested as solutions to even out high-low flows

This is a high risk, high cost wrong

choice because:

8/8/2019 Climate Change and the Himalayas

http://slidepdf.com/reader/full/climate-change-and-the-himalayas 16/16

Large Dams Dangerous

Solutions Climate change will increase threats to dams

from flash floods, initially increased high

flows, GLOFs

Increased variability in rivers means higher 

storage required, more cost

Much lower low season flows, or lower total

flows means under-performance of dams

High social and environmental impacts of dams

Uncertainty in climate change effects, large

dams represent high cost, inflexible response