Transcript Permafrost-and-Climate

C-Change in GEES
Changing Permafrost
Environments
Session Seven: Permafrost and
Climate Change
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
How to use the teaching slides
 These slides are not intended to form a complete lecture on the session
topic.
 These resources are designed to suggest a framework to help tutors
develop their own lecture material
 The resource slides comprise where appropriate; key points, case
studies, images, references and further resources.
 There are limited case studies included. Students can develop their
own portfolio of case studies as part of coursework activities
 These resources may be used for educational purposes only, for other
uses please contact the author
 These slides were last updated in February 2010
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Disclaimer
Links within this presentation may lead to other sites. These are provided for
convenience only. We do not sponsor, endorse or otherwise approve of any
information or statements appearing in those sites. The author is not
responsible for the availability of, or the content located on or through, any such
external site.
While every effort and care has been taken in preparing the content of this
presentation, the author disclaims all warranties, expressed or implied, as to
the accuracy of the information in any of the content. The author also (to the
extent permitted by law) shall not be liable for any losses or damages arising
from the use of, or reliance on, the information. The author is also not liable for
any losses or damages arising from the use of, or reliance on sites linked to
this site, or the internet generally.
Pictures, photographs and diagrams within this presentation have been
produced by the author unless otherwise stipulated
No content within this resource is knowingly an infringement of copyright. Any
infringement can be immediately rectified on notification of the author of the
resource
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Session Outline
• Recent Environmental Changes
• Climate Change during the 21st
Century?
• Potential Impacts of Climate
Change:
– Permafrost distribution
– Landscape
– Flora & fauna
– Human society
Figure SPM.3. IPCC, 2007: Climate Change 2007: The
Physical Science Basis. Contribution of Working Group I to
the Fourth Assessment Report of the Intergovernmental
Panel on Climate Change [Solomon, S., D. Qin, M. Manning,
Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller
(eds.)]. Cambridge University Press, Cambridge, United
Kingdom and New York, NY, USA, 996 pp.
• Positive feedbacks – Greenhouse
gas emissions associated with
permafrost degradation.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
FAQ 9.2. Fig 1
IPCC (2007)
Climate
Change 2007:
The Physical
Science Basis.
Contribution of
Working Group
I to the Fourth
Assessment
Report of the
Intergovernme
ntal Panel on
Climate
Change
[Solomon, S.,
D. Qin, M.
Manning, Z.
Chen, M.
Marquis, K.B.
Averyt, M.
Tignor and
H.L. Miller
(eds.)].
Cambridge
University
Press,
Cambridge,
United
Kingdom and
New York, NY,
USA,
Observed (black line) and modelled variations (blue = natural drivers; pink = natural
+ anthropogenic drivers) in temperature during the 20th Century.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Recent Environmental Changes
R.I. Waller
Thermal erosion and bank
collapse along the Colville River.
• Increased air temperatures in the
Arctic and Antarctic, especially during
the winter.
– E.g. 2°C warming in winter
temperatures over the 20th
century in the Arctic.
• Increased snowfall during the
winter.
– E.g. increase between 1950-90 of
20% in northern Canada and 11%
in Alaska.
• Modified ground thermal regime:
borehole temperature profiles show
the upper layers of permafrost to be
warming.
• Increased active layer thickness
and thawing of permafrost.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Fig 4.23 IPCC
(2007) Climate
Change 2007:
The Physical
Science Basis.
Contribution of
Working Group
I to the Fourth
Assessment
Report of the
Intergovernme
ntal Panel on
Climate
Change
[Solomon, S.,
D. Qin, M.
Manning, Z.
Chen, M.
Marquis, K.B.
Averyt, M.
Tignor and
H.L. Miller
(eds.)].
Cambridge
University
Press,
Cambridge,
United
Kingdom and
New York, NY,
USA,
Summary of the observed impacts of recent climate change on the cryosphere.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
R.I. Waller
Landscape evidence: Degradation of ice-wedge polygons illustrated by the
ponding of water above troughs – thermokarst development.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Climate Change Projections
• Large variation in model
projections for Arctic climate
change (warming of 2 – 9°C by
2100).
– Forcing scenarios.
– Cross-model variance.
IPCC temperature projections for the
Arctic
Fig 11.18 IPCC (2007) Climate Change 2007: The Physical
Science Basis. Contribution of Working Group I to the Fourth
Assessment Report of the Intergovernmental Panel on Climate
Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis,
K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge
University Press, Cambridge, United Kingdom
• Almost all GCMs project the
following for the high latitudes
within the Northern Hemisphere:
Temperature: Maximum warming during
the winter, little warming during the
summer.
Precipitation: Increased precipitation and
soil moisture levels during the winter.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Permafrost Distribution
• Global warming predicted to result in:
– reduced permafrost extent
– increased active layer thickness (30-40%; Stendel &
Christensen, 2002)
– reduced seasonal frost penetration
• Deep-seated continuous permafrost will remain intact due its
thermal inertia; upper layers will warm and active layers will
thicken.
• Discontinuous permafrost and Alpine permafrost may
disappear altogether, resulting in a migration of the permafrost
boundaries to higher latitudes and altitudes.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Illustration of the
predicted northern
migration of permafrost
in response to a 4°C
increase in surface
temperature
Figure From: French, H.M. 2007. The
Periglacial Environment (3rd ed.).
Wiley & Sons, Chichester (p.379).
© Wiley and Sons
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Locations of sites and changes in active layer thickness from selected sites
Fig 4.21 IPCC (2007) Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of
the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller
(eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA,
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Historical variation in
the monthly areal
extent (106 km2) of
seasonally frozen
ground for the period of
1901 through 2002 in
the Northern
Hemisphere
Fig 4.22 IPCC (2007) Climate Change
2007: The Physical Science Basis.
Contribution of Working Group I to the
Fourth Assessment Report of the
Intergovernmental Panel on Climate
Change [Solomon, S., D. Qin, M. Manning,
Z. Chen, M. Marquis, K.B. Averyt, M. Tignor
and H.L. Miller (eds.)]. Cambridge
University Press, Cambridge, United
Kingdom and New York, NY, USA,
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Landscape Changes
R.I. Waller
Retrogressive thaw slump
on Summer Island,
Mackenzie Delta
• Rapid melting of areas of ice-rich
permafrost: melting of ground ice will
lead to widespread thermokarst
development and landscape
degradation.
• Coastal recession due to a reduction in
sea ice duration, liquefaction,
subsidence and thaw lake generation.
• Increased fluvial erosion and
deposition.
• Increased rates of mass movement as
active layers deepen and become
longer lasting.
• Potential to significantly alter the
geography and ecosystem structure of
permafrost regions.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Sea Ice Extent
• Primary influence of winter warming in the Arctic is a predicted
reduction in sea ice extent and duration.
• In the Beaufort Sea during the 21st Century:
– Predicted increase in the duration of open-water conditions from
60 days to 150 days.
– Maximum extent of open-water conditions increases from 150200km offshore, to 500-800km.
• Would result in increased wave action and increased erosion of
permafrost coastlines.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Changing Extent of Sea Ice
Figures illustrate a significant decline in
the extent of sea ice in the Arctic over the
past 15 years in particular.
NH – Northern hemisphere
SH – Southern hemipshere
Figures are relative to the mean for the
entire period.
Fig 4.8. IPCC (2007) Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of
the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller
(eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA,
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Vegetation Changes
• Predicted climate change would significantly affect terrestrial
ecosystems through both direct climatic changes (temp., precipitation
& snow cover) and through changes in the permafrost distribution.
• Predicted changes to vegetation include:
– Contraction of the tundra zone to between 35-70% of its present
size by 2100.
– Associated northward migration of the boreal forests to higher
latitudes.
• Changes may in turn affect climate: e.g. expansion of tree cover may
lower surface albedo…
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Projected appreciable changes in terrestrial
ecosystems by 2100 relative to 2000
Fig 4.3. IPCC (2007) Climate Change 2007: Impacts, Adaptation and
Vulnerability. Contribution of Working Group II to the Fourth Assessment Report
of the Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani,
J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University
Press, Cambridge, UK.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
R.I. Waller
Migration of the treeline: the boundary between the boreal and tundra zones.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Human Impact
• Reduction in the load bearing capacity of permafrost: increased
likelihood of subsidence.
• Thaw subsidence related to active layer deepening: may damage
or destroy buildings, roads & pipelines.
• Increased frequency of slope failures, landslides and rockfalls
(increased risk of natural hazards).
• Thaw of alpine permafrost may result in destabilisation of cable car
stations, collapse of cable car pylons etc.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Building Collapse?
• Thaw of permafrost may lead to the
destruction of structures built on piles
driven into the permafrost.
• Khrustalev (Moscow State Univ.)
suggests that by 2030, assuming a
warming of 0.075°C/yr, all five-story
structures built between 1950 and
1990 in Yakutsk will be destroyed
unless remedial measures are taken.
http://www.flickr.com/photos/travfotos/249343703/
Nelson, F.E. et al. 2001. Subsidence risk from thawing permafrost. Nature, 410,
889-890.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Complex Feedbacks
• Warming of permafrost regions is likely to result in a variety of
feedbacks:
– Negative: increased net primary productivity.
– Positive: increased rate of decomposition.
• Concern that permafrost degradation may result in the emission of
additional greenhouse gases, exacerbating the rate of global
warming:
– Methane ebullition from thaw lakes.
– Thaw and dissociation of gas hydrates.
– Thaw of the yedoma formation in Siberia – major organic carbon
reservoir.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Arctic Gas Hydrates
• Ice-like combinations of
natural gas and water.
• Onshore and offshore
accumulations associated
with permafrost.
Distribution of organic carbon in Earth
reservoirs (excluding dispersed carbon in rocks
and sediments, which equals nearly 1000 times
this total amount). Numbers in gigatons (1015
tons) carbon
Source: USGS
• Size of accumulations are
uncertain; range from 2.8k to
8M trillion m3 of gas.
• Permafrost thaw could result
in release of substantial
quantities of methane.
http://www.aist.go.jp/GSJ/dMG/dMGold/hydrate/usgs/usgs_hydrate.html
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Methane Bubbling (ebullition)
• Ebullition accounts for 95% of CH4
emissions from lakes.
• Emits est. 3.8 terragrams of CH4 yr–1
(globally significant source of
atmospheric methane) .
Serrated lake margin associated with
permafrost degradation, ice-wedge
thaw and lake enlargement (R I Waller)
Walter, K. et al. 2006.
‘Methane bubbling from
Siberian lakes as a positive
feedback to climate warming’.
Nature , 443(7107), 71-75.
• Thawing permafrost along lake margins
accounts for most methane.
• Expansion of thaw lakes between 1974 &
2000 caused a 58% increase in emissions.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Yedoma (Ice Complex)
• Ice-rich silt deposited during the
Pleistocene, covering >1 million km2 of
north plains of Siberia & Central Alaska
to mean depth of ~25 m
• Contains grass roots & animal bones
(av. C concentration for yedoma
~2.6%)
Exposed carbon-rich soils from Kolyma
River, region Siberia. Soils are 53 m
thick.
Courtesy of Katey Walter
• Carbon reservoir in frozen yedoma ≈
500 Gt
Zimov, S.A.; Shuur, E.A.G. and Chapin III, F.S. (2006) ‘Permafrost and the
Global Carbon Budget’ Science 312(5780): 1612-1613
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
Lecture Summary
• Global warming predicted to be at its most severe in the Arctic;
warming of up to 10°C during winter months.
• Could lead to dramatic changes in permafrost areas:
– Total thaw of some areas of discontinuous and alpine permafrost
and warming of continuous permafrost.
– Extensive thermokarst development and erosion of ice-rich
permafrost.
– Large shifts in terrestrial ecosystems.
– Significant human impacts.
• Additional threat of positive feedbacks associated with decay of
ancient organics, methane ebullition and thaw of gas hydrates.
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
References
French, H.M. (2007) The Periglacial Environment (3rd ed.). Wiley & Sons,
Chichester.
IPCC (2007) Climate Change 2007: The Physical Science Basis. Contribution of
Working Group I to the Fourth Assessment Report of the Intergovernmental Panel
on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B.
Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University Press, Cambridge,
United Kingdom and New York, NY, USA.
IPCC (2007) Climate Change 2007: Impacts, Adaptation and Vulnerability.
Contribution of Working Group II to the Fourth Assessment Report of the
Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P.
Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University
Press, Cambridge, UK.
Stendel M., and Christensen J.H. (2002) Simulating permafrost zonation and
active layer depth change in a warmer climate with a coupled GCM. Geophysical
Research Letters 29,1632–1635
Dr Richard Waller, Keele University, [email protected]
C-Change in GEES: Changing Permafrost Environments – Permafrost and Climate Change
This resource was created by the University of Keele and released as an open educational resource through the 'C-change in
GEES' project exploring the open licensing of climate change and sustainability resources in the Geography, Earth and
Environmental Sciences. The C-change in GEES project was funded by HEFCE as part of the JISC/HE Academy UKOER
programme and coordinated by the GEES Subject Centre.
This resource is licensed under the terms of the Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales license
(http://creativecommons.org/licenses/by-nc-sa/2.0/uk/).
However the resource, where specified below, contains other 3rd party materials under their own licenses. The licenses and
attributions are outlined below:
1. From Slide 11 – Illustration of permafrost migration in response to climate change from: French, H.M. 2007. The Periglacial
Environment (3rd ed.). Wiley & Sons, Chichester, is the copyright of Wiley and Sons. Permission should be sought from the
copyright holders prior to re-use
2. The name of the Keele University and its logos are unregistered trade marks of the University. The University reserves all
rights to these items beyond their inclusion in these CC resources.
3. The JISC logo, the C-change logo and the logo of the Higher Education Academy Subject Centre for the Geography, Earth
and Environmental Sciences are licensed under the terms of the Creative Commons Attribution -non-commercial-No
Derivative Works 2.0 UK England & Wales license. All reproductions must comply with the terms of that license
Item Metadata
Author
Dr Richard Waller
Stephen Whitfield
Institute – Owner
Keele University, School of Physical and Geographical Sciences
Title
Permafrost and Climate Change PowerPoint Presentation
Date Created
March 2010
Description
Part Seven of Changing Permafrost Environment
Educational Level
3
Keywords (Primary keywords – UKOER &
GEESOER)
UKOER, GEESOER, yedoma, methane, human impact,
projection, environmental change, sea ice
Creative Commons License
Attribution-Non-Commercial-Share Alike 2.0 UK: England &
Wales