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Geographical Association Annual Conference 2006 “Lecture Plus” Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University www.esci.keele.ac.uk [email protected] 1. Problems & Opportunities 2.Examples 3.Ways Forward 4.Discussion School texts have not kept pace with glacier science over the last 30 years. My book in the GA series “Changing Geography” was a

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Page 1: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Geographical Association Annual Conference 2006 “Lecture Plus”

Glaciers and Glacial LandscapesDr Peter G Knight, Keele University www.esci.keele.ac.uk [email protected]

1. Problems & Opportunities

2. Examples

3. Ways Forward

4. Discussion

School texts have not kept pace with glacier science over the last 30 years. My book in the GA series “Changing Geography” was a response to this problem.

Page 2: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Geography is a fantastic subject!

It’s a wonderful world… Geography is all about exploring it.

Page 3: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

You don’t have to explore very long to realise that:

Everything is connected in a complex system

Glaciers, climate, sea-

level, tectonics,

geomorphology,

ocean currents, etc…

Page 4: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

1. glaciers

2. coasts

4. mountains, 5. deserts, etc., etc…

3. rivers

So, while you could design a whole course doing topics one at a time…

Page 5: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

…you don’t need to because they are all connected.

There’s a bigger picture to be interested in.

eg: the waterfall and the glacier

move in response to the same

forces.

Page 6: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

In understanding the landscapes around us, we recognise connections between topics across different scales…

We’re trying to understand the rules that control how all of these things work and how they fit together as part of a global system

Page 7: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Glaciers are very good for illustrating connections between parts of the global system at different scales… eg in the hydrological cycle

OCR Geography A-level Spec (2007): Module 2680 The Physical Environment

“As an introduction to this module the global hydrological cycle should be studied as a generalised, closed system.”

In many places, glaciers provide the only dry-season water supply

77% of Earth’s fresh water is in

ice sheets

Page 8: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Glacier science is exciting because it’s a subject in which there has been progress and discovery.

Teaching glaciers is problematic because different textbooks have kept up with the science to differing degrees, meaning that different books say different things, and few of them are up to date.

Page 9: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

• keeping up with new discoveries• choosing reliable teaching resources• knowing what to tell students

Especially when popular textbooks and websites such as the BBC are perpetuating out-of-date or incorrect information…

Fundamental problems in teaching Physical Geography:

Page 10: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

“…a significant minority of candidates appeared to have no relevant knowledge and understanding concerning drumlins…

Some simply stated that the glaciers somehow became tired, unable to carry on in lowland areas and dumped their load.”

AQA Examiners’ Report (GCE Geography A, 2005)

For example: Drumlins…

Page 11: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

“The most widely accepted view is that they were formed when the ice became overloaded with material and so the competence of the glacier was reduced. The reduced competence may have been due to the melting of the glacier or to changes in velocity…”

An explanation of DRUMLINS from the A-level textbook previously used by most of my incoming 1st-year Univ students (a book described by one teacher’s web site as “as good as it gets”):

From the textbook:

Page 12: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Lodgement till: This is sometimes referred to as Ground Moraine. It is the Material that is deposited under ice while the ice is moving. This action is almost like smearing and occurs when the weight of material becomes too great to carry on by the glacier. Features created by this deposition include Drumlins

http://www.bbc.co.uk/schools/16/sosteacher/geography/49085.shtml

From the BBC:

Page 13: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

http://www.revision-notes.co.uk/revision/187.html

Ice Movement

•Ice may move through one of these three processes:

1.Plastic Flowage: Ice has plastic qualities and may flow en-masse like a viscous liquid

2.Basal Slip: The process through which ice slips and slides over the underlying rock.

3.Internal Shearing: Movement similar to rock faulting involving differential sliding along planes.

•The speed of ice movement depends on the gradient of the slope and the thickness of the ice.

From revision-notes.co.uk:

Page 14: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Ice Erosion

•This involves three processes:

1.Plucking: Parts of the underlying rock are frozen into the base of the ice and pulled away.

2.Glacial Abrasion: The grinding process where stones frozen in the ice scrape and scratch against the underlying rock.

3.Sapping: The breaking of rocks by the alternate freezing and thawing of the ice at the bottom or sides of the mass.

http://www.revision-notes.co.uk/revision/187.html

From revision-notes.co.uk:

Page 15: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

New research:

puts “errors” into old textbooks

but

helps to make the subject more exciting to learn and to teach

This is both a problem and an opportunity

We can use glaciers to talk to students about science being dynamic, relevant, cutting edge, topical, interdisciplinary. We can use glaciers to illustrate complex linked systems, Global and local scale interactions, etc…

Page 16: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Climate-independent glacier fluctuations

Why does the ice reach exactly this point and no further?

BBC: “Glacier retreat is a sure sign of global warming.”

EX

AM

PL

EE

XA

MP

LE

Page 17: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Real answer 1. Changing basal friction:

1

3

2

1. Accumulation and thickening

2. Increased basal deformation, acceleration, advance, thinning…

3. Basal cooling, less basal deformation, slower flow, thickening, retreat.

EX

AM

PL

EE

XA

MP

LE Climate-independent

glacier fluctuations

Page 18: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

W. GreenlandW. Greenland

W.Greenland

Real answer 2. Floating glacier margins:

NB: Ice-shelf “collapse”

EX

AM

PL

EE

XA

MP

LE Climate-independent

glacier fluctuations

Page 19: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Pictures provided by Andrew Dugmore

Real answer 3. Ice-divide migration E

XA

MP

LE

EX

AM

PL

E Climate-independent glacier fluctuations

Page 20: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Myrdalsjokull, Iceland

Real answer 4. Surface debris inhibiting ablation

EX

AM

PL

EE

XA

MP

LE Climate-independent

glacier fluctuations

Page 21: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

The world is even more interesting than the text books tell us!

The basal ice layerIce streamsDeformable bedsSurging glaciersMegafloods and JokulhlaupsUnexplained UK landformsGlacier hazards from global warmingGlaciers flowing up-hillGlaciers controlling climateetc…

Page 22: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

EX

AM

PL

EE

XA

MP

LE

Drumlins: more interesting than the books tell us…

•Hypothesis 1: Deposition by ice

•Hypothesis 2: Erosion by subglacial megafloods

•Hypothesis 3: Deformation of subglacial debris

“I have spent the last 20 years or so pondering enormous floods from beneath the Pleistocene Ice Sheets. I think these floods may have formed drumlins, one of the most enigmatic landforms on Earth.

Prof. John Shaw, University of Alberta. http://www.engineering.ualberta.ca/civil/shaw.cfm

“The strongly polarized debate about the origin of drumlins exemplifies the problem when speculation is relatively unconstrained by definitive evidence…”

Prof. Geoffrey Boulton, University of EdinburghIn Knight, P.G. (2006) Glacier Science and Environmental Change (Blackwell).

Page 23: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

EX

AM

PL

EE

XA

MP

LE

Glacier motion: we

know more now than

we did when they

wrote the old books!

From revision-notes.co.uk:

1. Plastic flowage

2. Basal slip

3. Internal shearing

The real story:

1. Internal deformation of the ice

2. Sliding of the ice across its substrate

3. Deformation of the substrate beneath the ice

“Until the 1970s, sliding and internal deformation were the only mechanisms that scientists recognised. The idea that deforming beds contribute to glacier motion has been one of the most important ideas in recent decades. Substrate deformation is now a well-established part of our understanding.”

Page 24: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

EX

AM

PL

EE

XA

MP

LE

Glacier motion: examples of different glaciers

Glacier sliding creep deformation

Meserve - 100% -

Variegated (winter) - 100% -

Variegated (summer) 30% 70% -

Variegated (surge) 95% 5% -

Urumqui 1 3% 37% 60%

Breidamerkurjokull 12% - 88%

substrateice ice

Page 25: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

•bridging texts eg The GA’s “Changing Geography” series

•school/university interaction eg visits/workshops/correspondence

•teacher-researcher co-authorshipeg web-sites, text books, etc

Ways forward…

Page 26: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Glaciers provide valuable theme linking local/global, present/past, human/physical. We should include them more in our curricula.

The rapidly moving research frontier makes it exciting for students to learn about glaciers and to see their relevance to real-world issues such as environmental change. However, it makes it hard for textbooks and teachers to keep up.

Conclusions 1

Page 27: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

There are opportunities for resources that “bridge the gap” between A-level teaching and new discoveries.

There are opportunities for collaboration between Schools and Universities: why don’t teachers from schools and universities get together more?

Physical Geographers at Keele University would be glad to offer whatever help we can.

Conclusions 2

Page 28: Geographical Association Annual Conference 2006 Lecture Plus Glaciers and Glacial Landscapes Dr Peter G Knight, Keele University  p.g.knight@esci.keele.ac.uk

Thanks for listening.

Please get in touch!Dr Peter G Knight, Keele University

www.esci.keele.ac.uk/physicalgeography

[email protected]

A copy of this lecture, and related materials, will be placed on the GA website and on the physicalgeography.org.uk

website at http://www.physicalgeography.org.uk