Transcript IPCC - durba

WMO
Into a warming world
UNEP
R K Pachauri
Chairman, IPCC
Director-General, TERI
State of the World Symposium
Washington
15th January 2009
1
The Intergovernmental panel
on climate change:
Science at the service
of policy-making
2
Writing and review process
of the IPCC assessment reports
1. Experts review the first draft of the report
2. Governments and experts review the second
draft of the report and the draft Summary for
Policymakers
3. Governments review word-by-word the
revised draft Summary for Policymakers
3
The IPCC Fourth Assessment Report
(2007)
+2500 scientific expert reviewers
800 contributing authors
450 lead authors
+130 countries
4
References to the IPCC Fourth Assessment
Report in the Bali Action Plan (December 2007)
“Responding to the findings of the Fourth Assessment Report of the
Intergovernmental Panel on Climate Change that warming of the
climate system is unequivocal, and that delay in reducing emissions
significantly constrains opportunities to achieve lower stabilization
levels and increases the risk of more severe climate change impacts”
“[…] emphasizing the urgency to address climate change as indicated
in the Fourth Assessment Report of the Intergovernmental Panel on
Climate Change”
“[…] urgent and immediate needs of developing countries that are
particularly vulnerable to the adverse effects of climate change,
especially the least developed countries and small island developing
States, and further taking into account the needs of countries in Africa
affected by drought, desertification and floods”
5
Key findings of the IPCC
Fourth Assessment Report:
1. “Warming of the climate
system is unequivocal”
6
Observed changes
Global average
temperature
Global average
sea level
Northern hemisphere
snow cover
7
Global temperature change
Models using only
natural forcing
1
Models using both
natural and
anthropogenic forcing
0.5
Observations
0
1900
1950
Year
2000
8
The frequency of heavy precipitation events has
increased over most land areas
- Rainfall in Mumbai (India), 2005:
1 million people lost their homes
9
Heat waves have become more frequent
over most land areas
- Heat wave in Europe, 2003: 35 000 deaths
10
Intense tropical cyclone activity has increased
in the North Atlantic since about 1970
- Hurricane Katrina, 2005: up to $200 billion cost estimate
11
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Photo credit: GoodPlanet
More intense and longer droughts have been
observed over wider areas since the 1970s,
particularly in the tropics and subtropics
Key findings of the IPCC
Fourth Assessment Report:
2. “Continued GHG emissions [...] would
induce many changes in the global climate
system during the 21st century that would
very likely be larger than those observed
during the 20th century”
13
Carbon dioxide emissions
-2
Global atmospheric
concentrations of
greenhouse gases (GHG)
increased markedly as a
result of human activities,
with an increase
of 70% in 1970-2004
U.S. emissions have risen
by 14.7% in 1990-2006*
10000
*Source: EPA, 2008
5000
Time (before 2005)
0
14
Projected surface temperature changes
(2090-2099 relative to 1980-1999)
0 0.5 1 1.5 2 2.5 3 3.5 4 4.5
5 5.5 6 6.5 7 7.5 (oC)
Continued emissions would lead to further warming
of 1.1ºC to 6.4ºC over the 21st century
15
Examples of impacts associated with
global average temperature change relative to 1980-1999
0
1
2
3
5 oC
4
Increased water availability in moist tropics and high latitudes
WATER
Decreasing water availability and increasing drought in mid-latitudes and semi-arid low latitudes
Hundreds of millions of people exposed to increased water stress
Increased coral bleaching
ECOSYSTEMS
Most corals bleached
Widespread coral mortality
Terrestrial biosphere tends towards a net carbon source as:
15%
40% of ecosystems affected
Increasing species range shifts and wildfire risk
Ecosystem changes due to weakening of the meridional
overturning circulation
Complex, localised negative impacts on small holders, subsistence farmers and fishers
FOOD
Tendencies for cereal productivity
to decrease in low latitudes
Productivity of all cereals
decreases in low latitudes
Tendencies for some cereal productivity
to increase at mid- to high latitudes
Cereal productivity to decrease in
some regions
Increased damage from floods and storms
COASTS
About 30% of global coastal wetlands lost
Millions more people experience coastal flooding each year
Increasing burden from malnutrition, diarrhoeal, cardio-respiratory, infectious diseases
HEALTH
Increased morbidity and mortality from heat waves, floods, droughts
Changed distribution of some disease vectors
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Impacts on North America
Warming in western mountains is projected to
cause decreased snowpack and reduced summer
flows, exacerbating competition for over-allocated
water resources
Increased number, intensity and duration of
heatwaves will have potential for adverse
health impacts
Coastal communities and habitats will be
increasingly stressed by climate change impacts
interacting with development and pollution
17
Expected impacts on poor regions
People exposed to increased water stress by 2020:
 120 million to 1.2 billion in Asia
 12 to 81 million in Latin America
 75 to 250 million in Africa
Possible yield reduction in agriculture:
 30% by 2050 in Central and South Asia
 30% by 2080 in Latin America
 50% by 2020 in some African countries
Crop revenues could fall by 90% by 2100 in Africa
18
Key findings of the IPCC
Fourth Assessment Report:
3. “Neither adaptation nor mitigation
alone can avoid all climate change
impacts; however, they can
complement each other and
together can significantly reduce the
risks of climate change”
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Stabilisation scenarios
Global mean
temp. increase
(ºC)
Stabilization
level
(ppm CO2-eq)
Year CO2 needs
to peak
2.0 – 2.4
445 – 490
2000 – 2015
2.4 – 2.8
490 – 535
2000 – 2020
2.8 – 3.2
535 – 590
2010 – 2030
3.2 – 4.0
590 – 710
2020 – 2060
20
Costs of mitigation in 2030
Stabilisation
levels
(ppm CO2-eq)
Range of GDP
reduction
(%)
Reduction of
average annual
GDP growth
rates
(percentage pts)
445 - 535
<3
< 0.12
535 - 590
0.2 – 2.5
< 0.1
590 - 710
-0.6 – 1.2
< 0.06
Mitigation measures would induce 0.6% gain
to 3% decrease of GDP in 2030
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Impacts of mitigation on GDP growth
(for stabilisation scenario of 445-535 ppm CO2-eq)
GDP
Cost of mitigation
in 2030: max 3%
of global GDP
GDP without
mitigation
Mitigation would
postpone GDP
growth by one year
at most over the
medium term
GDP with
stringent
mitigation
Current
Schematic graph
2030
Time
22
Co-benefits of mitigation
 Health co-benefits from reduced air pollution
 Increased energy security
 More rural employment
 Increased agricultural production and reduced
pressure on natural ecosystems
Co-benefits provide the opportunity for
no-regrets policies and reduce mitigation costs
23
Key findings of the IPCC
Fourth Assessment Report:
4. “There is substantial […] potential for
the mitigation of global GHG
emissions over the coming decades
that could […] reduce emissions
below current levels”
24
All stabilisation levels assessed
can be achieved by deployment of a portfolio
of technologies that are currently available or
expected to be commercialised
in coming decades
This assumes appropriate and
effective incentives are in place for
their development, acquisition,
deployment and diffusion
25
Key mitigation instruments,
policies & practices
Research, development and demonstration
Appropriate energy infrastructure investments
Regulations and standards
Taxes and charges
Change in lifestyles & consumption patterns
Effective carbon-price signal
26
Barack Obama’s
New Energy for America plan (2008)
 Create 5 million new green jobs by investing
$150 billion over the next 10 years
 Ensure 10% of electricity comes from renewable
sources by 2012, and 25% by 2025
 Get 1 million hybrid cars on the road by 2015
 Implement an economy-wide cap-and-trade program
to reduce greenhouse gas emissions 80% by 2050
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The need for US involvement
US action on mitigation would:
 enable the achievement of global
stabilisation targets
 ensure US competitiveness in a world
market dominated by low-carbon products
 re-establish confidence in US leadership
on critical global issues
28
Man did not weave the web of life,
he is merely a strand in it.
Whatever he does to the web,
he does to himself.
Chief Seattle, 1854
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