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PHILIP ALLAN UPDATES
EDEXCEL GEOGRAPHY 2008
UNIT 1 WORLD AT RISK
Cameron Dunn, Chief Examiner
SESSION 1
Introducing climate change at AS
1. Basic ideas and themes – what are we aiming for?
Students will need to develop and understanding that:




Climate has changed in the past, on a range of timescales
The causes of climate change are both natural and human
Recent global warming is unprecedented; humans are (most likely) to blame
Global warming will have direct ecological, environmental and economic impacts, as well as
indirect impacts
 Predicting impacts is fraught with difficulty
 Global warming is a serious chronic hazard (as opposed to a ‘rare’ one like an asteroid
strike) which has potentially catastrophic and irreversible impacts
 Adaptation and Mitigation strategies can both be used to cope
 There is disagreement about what should be done, and difficult choices will need to be
made
2. Climate Change
Students need to develop an
understanding
that
climate
changes on a range of different
timescales:
 Geological – basically the
cycle of ice ages
 Historical – broadly, recorded
changes sine AD 0
 Recent – the global warming
‘era’ especially since 1970
Ice ages and interglacials occur at
regular
intervals
during
the
Quaternary, and this correlates
well with know CO2 concentrations
from ocean and ice cores. 
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Historical sources:
Proxy records (indirect indicators of past
climate) are a useful source of data for the
historical period.
They include artistic and photographic
sources, time series data such as grape
harvest dates, and written descriptions
and records.
They seem to clearly indicate two different
climatic periods in the past:
The Thames Frost Fair, 1814
Victorian ramblers on a Swiss glacier
 The
Medieval
Warm
Period
(sometimes called the Medieval
Climate Optimum) – dating from around
800-1300AD. The end of this period
coincides with the Black Death.
 The Little Ice Age – from about 15501880, but with colder spells around
1770 and 1850.
Students need to be aware that the use of
proxy data is fraught with difficult as:
 Extremes tend to be better recorded
than ‘normal’ conditions
 Long time series data are rare
 It is unclear, in some cases, what
climatic variable correlates best with
the proxy i.e. frosts, temperature,
rainfall etc.
 Much data may have been lost
Burgundy grape harvest dates
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Climate change
Most probable cause
Ice Ages in
Geological time
It is generally accepted that Milankovitch cycles are the basic cause
i.e. orbital variations cause a change in the amount, distribution and
seasonal timing of solar radiation.
It is often said the such variations amount to about 0.5C and that
feedback mechanisms (such as albedo from increased snow cover) are
required to ‘tip’ the earth into or out of an ice age – the temperature
difference between the two is about 5C.
(glacial /
interglacial
cycles)
(1000s-10,000s
years)
Historical
changes
( LIA / MWP)
(several 100
years)
Both the LIA and MWP have been linked to changes in solar output, on
timescales longer than the well-known 11 year sunspot cycle.
There is evidence of increased volcanic activity (ash, volcanic aerosols
and suplhur dioxide block out incoming solar radiation) during the LIA,
less so of decreased activity during the MWP.
Global Warming
The scientific consensus is that increased greenhouse gas emissions
trap more outgoing solar radiation in the lower atmosphere, generating a
net warming – the enhanced greenhouse effect.
(several decades)
Global Dimming
This is the theory that increased SO2 and NOx emissions work against
the enhanced greenhouse effect - CO2 and CH4 = warming but SO2 =
cooling (through blocking out sunlight i.e. dimming), therefore we have
yet to experience the full effect of GW.
One school of thought links sharply rising temperatures since 1990, to
the effort in MEDCs to clean up acid rain forming pollution (NO x and
SO2) i.e. as the atmosphere has been ‘cleaned’ we have seen a rising
amount of solar radiation getting through to the lower atmosphere.
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Worth thinking about?
What conclusion would you have drawn in 1975 when presented with this graph?
..and in 2008 when presented with this graph?
Make students aware of the difficulties of both determining the extent of global warming so far,
and suggesting what the future might hold.
Talk of an ice age was common in the 1970s; since the late 1970s there has been uninterupted
warming of about 0.5C but warming also occurred from 1910-1940, only to fall back and
stabilise in the 1950s and 1960s.
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3. Tricky Topics 1 – global warming
Scientific consensus? Joint Science Academies statement, 2005
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Prediction?
Students need to be aware that ‘crystal ball gazing’ for global warming is very difficult. This is
why the IPCC produce 6 different scenarios for warming and sea level rise. There is huge
uncertainty in many areas:
Physical systems
 The type and nature of positive and negative feedback mechanisms
 The possibility (or not) of a ‘tipping point’
 The role of the oceans (circulation and carbon sink)
 The reaction of forests to rising temperatures (grow more, or experience stress)
 The reaction of ice shelves and ice sheets
Human geography
 Population growth
 Economic growth
 Future fuel mix
 Public behaviour and lifestyle modification
http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr_spm.pdf
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Global warming is just unfair?
(maps from the Met Office, Climate and Environmental Stresses)
The table below shows a generalised mapping exercise using the 4 Met Office maps of key
areas at risk from climate change in terms of water stress, flooding, crop yields and human
health.
It is clear that 4 global regions bear 3 or 4 of the 4 risks. These are of course the poorest
regions with the largest number of conflicts, debt, dependency in aid, failed states etc. etc. Note
how the regions with the lowest carbon emissions are expected to suffer the most.
Water stress
and Drought
North America
Central America & Carib.
South America
Europe
Central Africa
Southern Africa
North Africa
Middle East/ Near East
Russia/ Central Asia
South Asia
SE Asia
Oceania
Flooding
Crop Yield
Human
Health
Carbon
emissions
per capita
(2002/
tonnes)
19.6
3.1
2.2
8.4
0.8
0.8
4.0
4.0
10.1
2.3
2.3
12.2
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What should be done – glossary
Adaptation
Putting in place management strategies to cope with a changing climate,
such as constructing improved flood defences or creating a more efficient
water distribution network. Many strategies are high cost.
Mitigation
Putting in place management strategies to reduce greenhouse gas
pollution and reduce the potential for further global warming, such as
switching to renewable energy sources.
Contraction & convergence
A mitigation framework which argues the developed world should reduce
its per capita carbon emissions, whilst allowing the developing world to
increase theirs and allow development to take place. The overall effect
would be a reduction in total emissions.
ETS
The EU Emissions Trading Scheme which began in 2005. All major
polluters in the EU (such as power stations and cement works) are given a
‘carbon cap’. To pollute above this cap, carbon credits have to be bought;
polluting below the cap means carbon credits can be sold.
‘Son of Kyoto’
The post-2012 agreement that will replace the Kyoto Protocol. Work on this
began in Bali in 2007. There is a growing consensus that it needs to be
tough.
Geo-engineering
Mega-scale engineering projects to change the earth’s environment and
make it more habitable. Well known options are mass ocean seeding with
iron filings to promote algal growth (and therefore carbon sequestration),
using mirrors in space to block out some solar radiation and stratospheric
sulphur spraying to create a cooling aerosol blanket.
Stabilization wedges
A structure for mapping emissions reductions from different economic
sectors. (see below)
Tipping point
The concern that the climate system will ‘switch’ to a new, stable, but very
different ‘norm’ rather than gradually change. Sometimes this is referred to
as ‘dangerous’ climate change. Some researchers think the point could be
450-550ppm carbon dioxide.
Polluter Pays Principle
The costs of pollution should be born by the polluter. It is widely accepted
in law but often ignored.
Carbon sequestration
Increasingly, this is taking to mean large scale ‘carbon capture and
storage’ (CCS) i.e. stripping C)2 out of power station emissions and
burying it underground in spent oil and gas reservoirs, salt mines and
porous rocks. It would allow the energy balance to remain as it is.
Hierarchy of Actions
The view that global warming needs to be tackled at international (Kyoto
etc.), national (UK renewable energy targets), local (recycling schemes)
and personal (switching lightbulbs) scales, all at the same time.
Uncertainty Principle
The decision making process that sets the costs and benefits of acting to
limit climate change now, against the costs and benefits of doing nothing.
The Stern Review suggested the cost of doing nothing was around 20% of
GDP.
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What should be done – think wedges!
A key issue is to help students understand what might be done to mitigate against ‘dangerous’
climate change.
The idea of stabilisation wedges from Princeton University provides a useful structure to allow a
greater understanding to develop.
The basic concept is shown here
(adapted from ‘the Guardian’). The
graph shows the predicted increase in
carbon dioxide levels to 2030. An
increase to 43.7 billion tonnes
equates to a carbon dioxide
concentration of 450-500 ppm – in
other
words
about
the
level
considered by many to be ‘dangerous’
(unavoidable increase of 2C).
The Princeton ‘wedge’ game assumes
a need to stabilise CO2 levels at
about 280ppm by 2050 and identifies
the task as a ‘stabilisation triangle’
showing how much carbon dioxide
needs to be removed for the system
(the Guardian image shown here is
aiming for a much lower level).
The triangle is then divided up into a
series of 7 wedges, each of which can
be achieved by a different reduction
strategy such as :




Efficiency
Fuel switching
Ending deforestation
Carbon Capture and Storage
Some of the strategies are suitably controversial (nuclear power) and it is possible for students
to come up with their own ideas i.e. replacing one they dislike with their own strategy.
The full game has been copied for you and can also be found at:
http://www.princeton.edu/~cmi/resources/stabwedge.htm
http://www.princeton.edu/~cmi/resources/CMI_Resources_new_files/CMI_Stab_Wedges
_Movie.swf for a flash video introduction you can use before the Game
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Something your average 17 year old can understand: VED
Car tax, or VED (Vehicle Excise Duty) is one
the minds of the average 17 year old. The UK
government is using VED as one of the key
planks of its mitigation strategy. The aim is to
use the tax system to change our car buying
behaviour.
VED linked to carbon dioxide emissions was
first introduced in 1998 (see table, right).
There is evidence that this policy has worked,
as car sales in Ban G have fallen since 2000,
and sales in Band C have risen sharply (see
graph).
2008-09 tax
Tax band
Up to 100
0
A
101-120
£35
B
121-150 (Renault Kangoo 1.5 DCi)
£120
C
151-165
£145
D
166-185 (Rover 75 1.8 Club SE)
£170
E
Over 186
£210
F
Over 226
£400
G
The 2008 budget changed the system to
introduce more VED bands, and penalise heavily
polluting cars with a ‘showroom tax’ and higher
annual VED:
% of UK car sales by VED tax band
A
2006
CO2 emissions (g/km)
B
C
D
E
F
2000
G
0%
20%
40%
60%
80%
100%
% all sales
From 2010-11
CO2 emissions (g/km)
Tax band
‘Showroom Tax’
Subsequent years
(Yr 1 + VED)
Up to 100 (VW Polo Bluemotion 1.4 Tdi)
0
0
A
101-110 (Citroen C1 1.0i)
0
£20
B
111-120 (Vauxhall Corsa 1.0i)
0
£35
C
121-130 (Ford Focus 1.6 TDCi)
0
£95
D
131-140 (Renault Kangoo 1.5 DCi)
£115
£115
E
141-150 (Citroen C4 Picasso 1.6 HDi)
£125
£125
F
151-160 (BMW 3-series 320i)
£155
£155
G
161-170 (Citroen C5 2.2 Hdi)
£250
£180
H
171-180 (Ford Mondeo 1.6 Estate)
£300
£210
I
181-200 (Rover 75 1.8i Club SE)
£425
£270
J
201-225 (Peugeot 407 saloon 2.0 Auto)
£550
£310
K
226-255 (Mercedes Benz E350
£750
£430
L
Over 255 (BMW X5)
£950
£455
M
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SESSION 3:
Resourcing the Compulsory case studies : The Arctic
Why the Arctic?
 It is generally agreed that the Artic will react more strongly to global warming than any other
region, so in that sense it is both a barometer of the impacts, and an early warning. Most
models estimate warming will be double the global average in the Arctic.
 In addition, there are indigenous people, which there are not in the Antarctic.
 The region is a zone of increasing resource exploitation, and potential conflict, as fossil fuels
are minerals run out.
 There is no ‘Arctic Treaty’ so the region is potentially vulnerable to disagreement.
Race to claim the Arctic
22 December 2007
From New Scientist Print Edition.
Rowan Hooper
"This isn't the 15th century," exclaimed an indignant Canadian foreign minister. "You can't go around the world and just
plant flags and say: 'We're claiming this territory'." Except that's exactly what Russia did in August when it audaciously
plonked a flag on the seabed under the North Pole, and lodged a claim of sovereignty with the United Nations.
Protestations apart, Canada has hardly been idle itself in the Arctic. In its own show of strength, in July it announced it
would spend a hefty US$7 billion patrolling the Arctic Circle with icebreakers, and after Russia planted its flag, Canada
announced plans for a military training base on Nunavut in its far north.
The dash to claim the "Arctic El Dorado" is well and truly on, and the reasons why the race started in earnest in 2007 are
twofold. First, the summer sea ice melted more than ever. This means the prospect of plundering the Arctic seabed for
its riches of oil, gas and minerals is closer than ever. Similarly, the fabled North-West Passage became navigable for the
first time, which could slash thousands of miles off the shipping route from Europe to Asia.
The second reason is that claims to the Arctic shelf made under the UN Convention on the Law of the Sea must be
made within a decade of ratifying it, so Russia only has until 2009, Canada until 2013, and Denmark until 2014.
As the ice melts, the Arctic squabbling continues. Denmark says it has a claim to the North Pole, via its self-governing
province of Greenland. The Canadians say the pole is theirs, while Russia has already set down its flag. Funny how
there's less clamour to preserve the ice than there is to plunder the riches beneath it.
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There are growing concerns about the future of the Arctic, these can be summarized as:
 Fears over the future of the Greenland Ice Cap. Recent research suggests melting is
increasing, and the rate of melting is beyond the range of most predictions.
 Fears over the loss of ecosystems associated with the tundra. Whilst biodiversity is low,
within certain species groups it is very high; Arctic flora and fauna cannot migrate north,
unlike lower latitude ecosystems.
 Fears that this vulnerable area will be the next great resource frontier (see article above)
adding to pressures from climate change.
 Concerns that culture and tradition among the indigenous people will be swept aside as
climate change accelerates.
In terms of indigenous people, the Arctic has a population of about 4 million, but there are
numerous indigenous groups and sub-groups:
Despite much modernization, many indigenous people are still heavily dependent, directly, on
the natural environment for some or all of their resources. In this sense they are especially
vulnerable to change.
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In Alaska, significant changes are already being felt by humans :
Arctic climate headlines:
3-4C warming since the 1950s
6-8C warming by 2100 considered a distinct possibility
Increased river discharge
10% decline in snow cover since late 1970s
10-20% decline in snow cover expected by 2070
Precipitation increased 8% since 1900, mostly as rain; further increases
expected
 Permafrost has warmed by 2C since 1970s; shifts northward of the
permafrost zone of 100s km are expected.







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Summary of observed and potential ecological impacts:
Area of concern
Outbreaks of insects
Forest fires
Agriculture
Observed impacts
Spruce bark beetle is already on the
rise; up to 2 million hectares of
spruce forest already damaged
Areas burned have doubled in
western North America since the
1970s
Little impact so far
Polar Bears
Growing
concern
over
numbers in some regions
falling
Ice dependent seals
These are seals which give birth on
sea ice, and haul themselves onto
sea ice e.g. ringed seals
Cod and Shrimp
These fisheries have already been
observed as closely related to
climate
Tundra Plants
Vegetations zones are already
changing, with and advance of
forests and loss of grassland
Ice crusting
This occurs when unexpected winter
thaws are followed by fresh snowfall;
this prevents Lemmings, Musk Ox
and Caribou from digging through
the snow to forage
Potential impacts
Likely to increase, as 2 year +
hard frosts become rare and
beetle larvae survive
A further 80% increase in
annual forest fires is expected
by 2100
Significant changes could
increase growing seasons,
allowing more land to be
converted to grazing
An ice free Arctic could see
populations crash, as bears
rely on ice for transport;
populations used to isolation
are
unlikely
to
survive
increasing
contact
with
Browns and Grizzlys
Similar to polar bears, many
species so depend on sea ice
that their populations may
become extinct.
Cod populations could expand
hugely as climate warms,
whereas shrimp populations
are likely to crash
If permafrost continues to
melt, long term waterlogging
will significantly change flora
and insect life over large
areas, with knock-on effects
to large mammals.
Population
collapses
are
highly likely due to winter
starvation
Summary
The arctic ecosystem is highly vulnerable as it is deeply adapted to an intense, seasonal
climate. It relies upon a continuous, very cold winter.
There is evidence that this winter is fast disappearing to be replaced by more variable coldthaw conditions which lead to iceing, fails to kill pests, and promotes waterlogging.
Many species are not in a position to migrate to new latitudes, and others which depend directly
on sea ice may simply disappear.
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January 8, 2008 (New York Times)
In Greenland, Ice and Instability
By ANDREW C. REVKIN
The ancient frozen dome cloaking
Greenland is so vast that pilots have
crashed into what they thought was a
cloud bank spanning the horizon.
Flying over it, you can scarcely
imagine that this ice could erode fast
enough to dangerously raise sea levels
any time soon.
Along the flanks in spring and
summer, however, the picture is very
different. For a lengthening string of
warm years, a lacework of blue lakes
and rivulets of meltwater have been
spreading ever higher on the ice cap.
The
melting
surface
darkens,
absorbing up to four times as much
energy from the sun as unmelted snow,
which reflects sunlight. Natural
drainpipes called moulins carry water from the surface into the depths, in some places reaching bedrock.
The process slightly, but measurably, lubricates and accelerates the grinding passage of ice toward the
sea.
Most important, many glaciologists say, is the breakup of huge semis-ubmerged clots of ice where some
large Greenland glaciers, particularly along the west coast, squeeze through fjords as they meet the
warming ocean. As these passages have cleared, this has sharply accelerated the flow of many of these
creeping, corrugated, frozen rivers.
All of these changes have many glaciologists “a little nervous these days — shell-shocked,” said Ted
Scambos, the lead scientist at the National Snow and Ice Data Center in Boulder, Colo., and a veteran of
both Greenland and Antarctic studies.
Some fear that the rise in seas in a warming world could be much greater than the upper estimate of
about two feet in this century made by the Intergovernmental Panel on Climate Change last year. (Seas
rose less than a foot in the 20th century.) The panel’s assessment did not include factors known to
contribute to ice flows but not understood well enough to estimate with confidence. All the panel could
say was, “Larger values cannot be excluded.”
A scientific scramble is under way to clarify whether the erosion of the world’s most vulnerable ice
sheets, in Greenland and West Antarctica, can continue to accelerate. The effort involves field and
satellite analyses and sifting for clues from past warm periods, including the last warm span between ice
ages, which peaked about 125,000 years ago and had sea levels 12 to 16 feet higher than today’s.
The Arctic Council, representing countries with Arctic territory, has commissioned a report on
Greenland’s environmental trends, to be completed before the 2009 climate-treaty talks in Copenhagen,
at which the world’s nations have pledged to settle on a long-term plan for limiting human-caused global
warming.
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Key Arctic web resources:
The National Oceanographic and Atmospheric Administrations Arctic resource pages:
http://www.arctic.noaa.gov/
The IPCC 4th Assessment regional report chapter (15) on impacts in the Polar Regions:
http://www.ipcc.ch/ipccreports/ar4-wg2.htm
The Arctic Climate Impact Assessment (ACIA) 2005
http://www.acia.uaf.edu/
The Arctic Council website
http://www.arctic-council.org/
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