Climate Change and
the IPCC Fourth
Assessment
Jean Palutikof
Head, Technical Support Unit
Working Group II
IPCC
Met Office, Exeter, UK
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What is the greenhouse effect?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What is our contribution?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What is our contribution?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Other gases are important
as well as CO2
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What is the evidence for climate
change?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
And from the longer record?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What is the expected impact on climate?
Change in global
surface temperature
Change in global mean
sea level
IPCC Working Group II: Impacts, Adaptation and Vulnerability
And at the regional scale?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What tools do we have available?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Pattern of annual average temperature change, 2080s
relative to present day for A1F1 (left) and B2 (right)
emissions scenarios
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Precipitation indices: maximum length of dry
spell per year (2070-99 minus 1961-90)
50oN
A2a:
30
o
45 N
20
A2a scenario
o
40 N
A2a
10
0
35oN
-10
– Longer by 15-30
days in centre and
south east
– 10 days shorter over
northern Europe
o
30 N
10oW
0o
10oE
20oE
30oE
40oE
50oN
30
o
45 N
20
40oN
10
35oN
0
B2a
B2a:
– Smaller changes than
A2a
– wetter Eastern Med.
-10
o
30 N
10oW
0o
10oE
20oE
30oE
40oE
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Precipitation indices: max. 5-day running total
(2070-99 minus 1961-90)
50 N
o
40
45oN
20
A2a scenario
40oN
35oN
-20
o
30 N
0
10oW
0o
10oE
20oE
30oE
40oE
-40
50 N
o
40
45oN
20
o
40 N
0
35oN
-20
30oN
o
10 W
0
o
o
10 E
o
20 E
o
30 E
o
A2a:
– Lower intensity, by
10-20 mm, in future,
particularly in west
– Increased intensity
in centre and
Adriatic
B2a:
– Smaller changes
than A2a
– Clearly higher
intensity in Italy
-40
40 E
IPCC Working Group II: Impacts, Adaptation and Vulnerability
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What are the implications for
European urban areas?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Impacts
• Impacts of more intense rainfall on
storm drains/sewers
• Heat stress
• Changes in circulation and the
implications for air pollution
• Coastal cities and tidal surge
• Implications of increased wind storm
IPCC Working Group II: Impacts, Adaptation and Vulnerability
All cause death rate
90000
•
y = 53.259x 2 - 2167.6x + 69562
R2 = 0.67
80000
•
60000
•
50000
40000
30000
-5
0
5
10
15
20
25
°C
Deaths per day and mean temperatures in July
All months r2 = 0.67
Deaths per day
number of deaths
70000
Strongest associations with temperature
are between August and March
In November, 64% of the variance in the
death rate is explained by temperature
The reduction in the death rate due to a 1
degC increase in temperature and a 10mm
decrease in rainfall is in the range 1-3%
1500
1480
1460
1440
1420
1400
1380
1360
1340
14
15
16
17
18
19
20
Mean temperature in degrees C.
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Adaptation
• Through design:
– Of urban spaces
– Of buildings
• Through behaviour
– Use of the outdoor environment
– Transport policies
– Air conditioning
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Mitigation activities
• Energy use
– Reduction in demand
– Use of renewables
• Fuel-efficient transport systems
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What about surprises/abrupt
climate change?
• Collapse of the West Antarctic Ice Sheet
• Melting of the Greenland ice cap
• Collapse of the North Atlantic
thermohaline circulation
• Of course, the real surprises are the
ones we haven’t thought of
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Is there controversy?
IPCC Working Group II: Impacts, Adaptation and Vulnerability
The Inter-governmental Panel on
Climate Change
• To assess the scientific literature on climate
change
• To support the UNFCCC
• Three Working Groups
– Science
– Impacts, Adaptation and Vulnerability
– Mitigation and Policy
• Now carrying out the Fourth Assessment
• To report in 2007
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Structure of WGII
• Two Co-Chairs:
– Martin Parry, UK
– Osvaldo Canziani, Argentina
• Six Vice-Chairs
• One TSU with four full-time staff
• Writing team of around 200 CLAs, LAs and REs, plus
Contributing Authors
• Four Lead Author Meetings
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Working Group II AR4
Summary for Policymakers + Technical Summary
Introduction
1. Assessment of observed changes and responses in natural and managed
systems
II. ASSESSMENT OF FUTURE IMPACTS AND ADAPTATION: SECTORS
2. New assessment methodologies and the characterisation of future
conditions
3. Fresh water resources and their management
4. Ecosystems, their properties, goods and services
5. Food, fibre and forest products
6. Coastal systems and low-lying areas
7. Industry, settlement, and society
8. Human health
III. ASSESSMENT OF FUTURE IMPACTS AND ADAPTATION: REGIONS
9: Africa, 10: Asia, 11: Australia and New Zealand, 12: Europe, 13: Latin
America 14: North America, 15: Polar Regions (Arctic and Antarctic),
16: Small Islands
IV. ASSESSMENT OF RESPONSES
17. Assessment of adaptation practices, options, constraints and capacity
18. Inter-relationships between adaptation and mitigation
19. Assessing key vulnerabilities and the risk from climate change
20. Perspectives on climate change and sustainability
IPCC Working Group II: Impacts, Adaptation and Vulnerability
Supposing you wanted to
contribute to the process
• The IPCC assesses the literature
• It seeks to be inclusive and consensual
• The preference is for fully refereed
publications
• There are procedures to deal with ‘grey
literature’
• Submissions of literature and/or text can be
made to the appropriate CLA, the Co-Chairs
or the TSU, for consideration
IPCC Working Group II: Impacts, Adaptation and Vulnerability
The message from IPCC TAR
• Emissions of greenhouse gases and aerosols due to
human activities continue to alter the atmosphere in
ways that are expected to alter our climate
• There is new and stronger evidence that most of the
warming observed over the last 50 years is
attributable to human activities
• Human influences will continue to change
atmospheric composion throughout the 21st century
• Global temperatures and sea level are projected to
rise under all IPCC SRES scenarios
• Anthropogenic climate change will persist for many
centuries
• See www.ipcc.ch
IPCC Working Group II: Impacts, Adaptation and Vulnerability
What will be the principal
messages of the AR4?
IPCC Working Group II: Impacts, Adaptation and Vulnerability