The science of climate change the need for a global response

1
The science of climate change - the need for a
global response

• Sir David King
• Chief Scientific Adviser to
• HM Government
• Linnean Society
• 19 February 2007

2
21st Century Challenges

• Population growth
• Resources
• Environment
• Infectious diseases
• Climate Change

3
Earths Atmosphere
Source Strategic Plan for the U.S. Climate
Change Science Program, A Report by the Climate
Change Science Program and the Subcommittee on
Global Change Research (July 2003) figure 3.1
4
Carbon cycles
5
The earths energy budget
6

383ppm (2006)
Fedorov et al, Science 312 (2006) 1485
7

Source Hadley Centre
8
Understanding impacts
Source Hadley Centre
Source Stern Review
9
Greenland ice sheet
Source Met Office
10
Surface Melt on Greenland
Melt descending into a moulin, a vertical shaft
carrying water to ice sheet base
Source Roger Braithwaite, University of
Manchester
11
Difficult non linear feedbackphenomena

• Deep sea methane clathrates
• Weakening the Atlantic Overturning
  Circulation-Thermohaline Gulf Stream, global heat
  conveyor
  
• Equatorial forest switch from CO2 net absorption
  to net emission
  
• Change in Earths net albedo, including global
  ice and cloud cover

12
Resources Ecosystem services
13
Unprecedented change Biogeochemical Cycles

• Since 1960
• Flows of biologically available nitrogen in
  terrestrial ecosystems doubled
  
• Flows of phosphorus tripled
• More than 50 of all the synthetic nitrogen
  fertilizer ever used has been used since 1985
  

Human-produced Reactive Nitrogen
Humans produce as much biologically available N
as all natural pathways and this may grow a
further 65 by 2050
Source Millennium Ecosystems Assessment
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Degradation of ecosystem services often causes
significant harm to human well-being

• The total economic value associated with managing
  ecosystems more sustainably is often higher than
  the value associated with conversion
  
• Conversion may still occur because private
  economic benefits are often greater for the
  converted system

Source Millennium Ecosystems Assessment
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Biodiversity loss
Living Planet Index 1970-2000

• Causes
• habitat destruction and fragmentation
• over-exploitation and bad management
• invasive alien species
• pollution
• climate change

Source WWF Living Planet Report, 2002
16
Significant and largely irreversible changes to
species diversity

• The distribution of species on Earth is becoming
  more homogenous
  
• Humans have increased the species extinction rate
  by as much as 1,000 times over background rates
  typical over the planets history (medium
  certainty)
• 1030 of mammal, bird, and amphibian species are
  currently threatened with extinction (medium to
  high certainty))

Source Millennium Ecosystems Assessment
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Climate Change and Biodiversity

• By the end of the century, climate change and its
  impacts may be the dominant direct driver of
  biodiversity loss and changes in ecosystem
  services globally.

The golden toad of Costa Rica has the dubious
distinction of being the first species to have
become extinct due to climate change (RSPB).

18
Changes in distribution of zooplankton groups in
the N E Atlantic, 1958 - 2002
From Beaugrand et al. (2002). Science. 296
19
Changes in plankton have implications
for higher trophic levels e.g fish
From Beaugrand et al. (2003) Nature 426
20
Committed to extinction?
From Chris Thomas et al (2004) Nature
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Amazon rainforest could turn to savannah

• Climate change and deforestation could convert
  the majority of the Amazon rainforest into
  savannah
  
• massive impacts on the world's biodiversity and
  climate

22
Adapt and Mitigate

• We must adapt in preparation for the significant
  changes ahead and manage the risks country by
  country.
  
• We have to actively mitigate against the
  production of greenhouse gases by
  
• Switching to low carbon energy sources
• Energy efficiency

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Biodiversity and mitigation

• Exploit synergies Avoiding deforestation, can
  have substantial biodiversity benefits and tackle
  mitigation (deforestation - 18 global CO2
  emissions)
• Avoid conflicts Need to understand implications
  of biofuels for biodiversity and ecosystem
  services
  

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Biodiversity and biofuels

• Ongoing research on benefits of biodiversity over
  monocultures

Source Tilman et al, (2006) Science 314, p1598
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Global dimensions of the mitigation problem
Source Carbon Trust
26
Emissions path to stabilisation
Global emissions (gigatonnes of CO2 equivalent
gases per year)
Source Stern Review
27
G8 Gleneagles, UK 2005

• Climate change UK government priority
• Agreement to take forward Dialogue on Climate
  Change
  
• G8 countries and other (developing) countries
  need to be involved
  

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Second Gleneagles Dialogue, Mexico October 2006

• Science and economic analysis (Stern) is now
  accepted
  
• Cost of inaction to global economies is huge
• Need to both adapt and mitigate
• Energy efficiency carbon capture storage new
  low carbon sources all require investment now.
  

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• Energy Technologies Institute
• Public-Private partnership between UK Government
  and industry
  
• BP, Shell, EDF, EOn, Caterpillar Inc, Rolls
  Royce, SSEG all core partners
  
• Will invest over 1bn in energy research, design,
  demonstration and development over 10 years
  
• Looking to develop links with other countries

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Conclusion

• Climate change is a global problem which needs a
  global solution
  
• UK is developing a robust and coherent strategy
• Need to address both transport and the built
  environment as well as decentralised energy
  issues
  
• Action is affordable Inaction is not!