1. DYNAMIC PLANET Glaciers
2012 SUMMER INSTITUTE
DYNAMIC PLANET Glaciers

2. PRESENTED BY Mark A. Van Hecke
2012 SUMMER INSTITUTE
PRESENTED BY Mark A. Van Hecke

3. 2012 SUMMER INSTITUTE
DISCLAIMER: This presentation was prepared using draft rules. There may be some changes in the final copy of the rules. The rules for this event that are in the current year’s Coaches Manual and Student manuals will be the official event rules.

4. Presentation Objectives
Provide 2012 Summer Institute Participants with an overview of 2013 Dynamic Planet Rules.
Provide 2012 Summer Institute Participants with an overview of 2013 Dynamic Planet Event Topic Areas and training strategies to use with students.

5. 2013 Event Description
In Dynamic Planet, students will use science process skills to complete tasks related to glaciation and long term climate change

6. What Students Will Do:
Students will be presented with one or more tasks using science process skills including:
Analysis and interpretation of erosional and depositional landforms created by glaciers
Analysis of geologic maps that include glacial deposits to determine the sequence of events over episodes of glacial advance and retreat
Interpretation of oxygen isotope data from a sediment core to identify changes in sea level caused by glacial advances and retreat

7. Activity One: Make Your Own Glacier
In this activity, you will get directions to create and you will observe a melting glacier.

8. What is a Glacier?
A glacier is a thick mass of ice that forms over hundreds or even thousands of years…

9. What is a Glacier?
Snow- and lots of it is the raw material from which glacial ice originates…
Glaciers form on land in places where more snow falls in the winter than that which melts in the summer
Over time, the snow compacts into granular or hardened snow

10. What is a Glacier?
This granular snow then recrystallizes to form firn- an intermediate stage between snow and ice
Snowflakes are compressed under the weight of the overlying snowpack. Individual crystals near the melting point are semiliquid and slick, allowing them to glide along other crystal planes and to fill in the spaces between them, increasing the ice's density. Where the crystals touch they bond together, squeezing the air between them to the surface or into bubbles.
Sampling the surface of a glacier. There is increasingly denser firn between surface snow and blue glacier ice.
Firn from South Cascade Glacier, 80x magnified.
Firn field on the top of Säuleck, Hohe Tauern
Firn (from German Firn with the same meaning, cognate with for) is partially compacted névé, a type of snow that has been left over from past seasons and has been recrystallized into a substance denser than névé. It is ice that is at an intermediate stage between snow and glacial ice. Firn has the appearance of wet sugar, but has a hardness that makes it extremely resistant to shovelling. Its density generally ranges from 550 kg/m³-830 kg/m³ and can be often found underneath the snow that accumulates at the head of a glacier.

11. What is a Glacier?
Over time, the firn continues to compact and recrystallize into glacial ice
Firn is often found underneath the snow that accumulates at the head of the glacier

12. Make Your Own Glacier Now… let’s make our own glacier
First, take a mixture of dirt and rocks of various sizes.
Add approximately 1 tablespoon of the mixture per ice cube that you will make.
Add water and freeze the mixture overnight

13. Make Your Own Glacier
Take the ice cube (aka the glacier) and turn it upside down onto the surface
Next, give the glacier a push forward. You might also push it down slightly into the surface.

14. Make Your Own Glacier Make observations as the ice cube is melting..
What is happening to the pebbles, dirt and rocks that were in the glacier?
Sediment is unsorted and the piles of sediment are of mixed sizes.

15. Make Your Own Glacier
The piles of dirt could be moraines that are left at the end of a glacial advance

16. Make Your Own Glacier
You might also see large boulders or erratics that appear out of place in comparison to other sediments left by the glacial retreat

17. Make Your Own Glacier
There could also be basins that filled with meltwaters when the glacier retreated.
These are kettles or kettle lakes.

18. 2013 Event Topics:
The 2013 Dynamic Planet Event will emphasize the following three key topic areas:
Glacial formation
Glacial and ice sheet types-primarily alpine and continental
Glacial erosion, erosional landforms and sediment transport
Glacial depositional landforms and sediments
Periglacial environmental processes and landforms

19. 2013 Event Topics:
The 2013 Dynamic Planet Event will emphasize the following three key topic areas:
Glaciers in the hydrologic cycle, impacts on climate, streams, lakes and oceans
Pleistocene and pre-Pleistocene glacial history
Theories explaining glacial and ice sheet advance
Glaciers as indicators of modern global climate change

20. Forms of Glaciers
Alpine glaciers are masses of glacial ice that accumulate in mountainous uplands and plateaus…

21. Forms of Glaciers
Continental glaciers are enormous ice sheets that flow out from one or more centers to completely cover all but the highest areas of underlying terrain…

22. Erosional Landforms
The forward motion of a glacier is known as its ‘flow’…

23. Erosional Landforms
In the process of moving forward, glaciers pick up enormous amounts of debris as they loosen, break off and incorporate pieces and blocks of rock into the ice…
This is a process known as ‘plucking…’

24. Erosional Landforms
This embedded material may create long scratches or grooves called ‘glacial striations’ as the glacier moves forward acting like a giant rasp as it moves across the rock…

25. Erosional Landforms
The pulverized rock that results from abrasion is called ‘rock flour…’

26. Erosional Landforms
Cirques
Horns

27. Erosional Landforms
Arêtes
Kettles

28. Depositional Landforms:
Recall that glacial ice carries enormous amounts of debris within the ice and as it moves forward like a bulldozer scooping sediment in front of it…
Keep in mind that ice is melting at the front of a glacier and that as the ice melts, materials are being deposited…

29. Depositional Landforms
‘Drift’ is a general term used to describe sediments of glacial origin…

30. Depositional Landforms
‘Till’ refers to materials that are deposited directly as glacial ice melts and drops its load of rock fragments…

31. Depositional Landforms
‘Stratified drift’ refers to sediments that are not directly deposited by a glacier, but rather reflect the sorting action of glacial meltwaters…

32. Depositional Landforms
‘Erratics are larger rocks and boulders carried by glaciers far from their place of origin…

33. Depositional Landforms
‘Drumlins’ are streamlined hills composed of glacial till…

34. Depositional Landforms
‘Eskers’ are depositional ridges made by streams flowing in tunnels beneath the ice

35. Depositional Landforms
‘Kames’ are steep sided hills composed of sand and gravel…

36. Depositional Landforms
‘Moraines’ are large deposits of glacial till that form a variety of depositional features…

37. Depositional Landforms
‘Lateral Moraines’ are ridge like piles of till that accumulate along the sides of valley glaciers…

38. Depositional Landforms
‘Medial Moraines’ form where adjacent lateral moraines merge into a single long ridge of till…

39. Depositional Landforms
‘End Moraines’ form where the terminus or end point of an active glacier remains at the same location for a number of years piling up into an increasingly larger ridge or hill…

40. Depositional Landforms
‘Terminal Moraines’ mark the farthest advance of a glacier.

41. Activity Two: Identifying Glacial Features on Topographic Maps
In this activity, you will identify landforms associated with glaciers on a topographic map.
You will need the Hyannis, Massachusetts , Marmot Mountain, Montana, and Palmyra, New York topographic map pages to complete the activity.

42. Identifying Glacial Features on a Topographic Map:
Hyannis, Massachusetts
Describe the topography of the map indicated by the red X shown on the screen?
What term related to glaciers can be used to describe this topography? X
This is a moraine as indicated by the well defined hill/depression zone shown here

43. Identifying Glacial Features on a Topographic Map:
Hyannis, Massachusetts
Read the contour lines surrounding the four ‘Bs’ in the northern half of the map. What type of glacial landforms are they likely to be?
What category of glacial landforms are the four ‘Bs?’
These depressions are Kettle LakesKettles were formed as large blocks of ice formed depressions and then melted.

44. Identifying Glacial Features on a Topographic Map:
Hyannis, Massachusetts
Read the contour lines surrounding areas labeled D in the southern half of the map.
What category of glacial landforms are the D Regions of the map?
The D regions of the map form areas of outwash plain as indicated by the broad, lower elevation.

45. Identifying Glacial Features on a Topographic Map:
Hyannis, Massachusetts
What might account for the swampland in the NW/North Central region of the map?
The lower elevated land indicated by the box was depressed by the weight of the glacier at the edge of the moraine creating a broad area of poorly drained land.

46. Identifying Glacial Features on a Topographic Map:
Marmot Mountain, Montana
What type of glacial landform likely is indicated by C, O and M?
These are cirques-areas-basins where glacial ice accumulates and then begins to flow downward to lower elevations

47. Identifying Glacial Features on a Topographic Map:
Marmot Mountain, Montana
What type of glacial landform likely is indicated by N?
N indicates a glacial tarn occupying the depression. Tarns are glacial lakes occupying former cirque basins

48. Identifying Glacial Features on a Topographic Map:
Palmyra, New York
What type of glacial landform likely is indicated by B and E?
B and E are drumlins. Drumlins are formed by glacial ice acting upon ground moraines or till. The lee side (low)of the Drumlin can be used to indicate the direction of ice flow

49. Identifying Glacial Features on a Topographic Map:
Palmyra, New York
What might explain the linear movement of streams F and G in the SW corner of the map?
The streams lie within lowlands separated by parallel drumlins

50. Summary:
Provide 2012 Summer Institute Participants with an overview of 2013 Dynamic Planet Rules.
Provide 2012 Summer Institute Participants with an overview of 2013 Dynamic Planet Event Topic Areas and training strategies to use with students.