instructor guide chapter 1 introduction to … 1 introduction to paleoclimatic records instructor...

Ch 1 Introduction to Paleoclimatic Records Instructor Guide

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INSTRUCTOR GUIDE Chapter 1 Introduction to Paleoclimate Records

SUMMARY

This exercise serves as an introduction to paleoclimate records, with emphasis on sediment and ice cores. In Part 1.1, you will compare and contrast the temporal and spatial scope of major

paleoclimate archives: tree rings, speleothems, glacial ice, lake and marine sediments, and sedi-

mentary rocks. In Part 1.2 you will read about the 780,000 year old Owens Lake core record and create a summary figure to synthesize the paleoclimatic data and interpretations. In Part 1.3 you

will consider the challenges and strategies for obtaining cores from glacial ice and the sub-seafloor;

in addition you will consider issues of sampling, reproducibility, resolution, and cost, which are common issues for all paleoclimate archive research.

FIGURE 1.1. Cross sections (a view perpendicular to growth or accumulation) of (a) a tree (courtesy of Colin Bielby), (b) a cave deposit (speleothems; courtesy of John Haynes; inset photo from ANSTO.), (c) several tens of meters of glacial ice (courtesy of Lonnie Thompson), (d) a coral (Hough, 2010), and (e) a sedimentary sequence (Marwan et al., 2003).


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Goal: to become familiar with the primary paleoclimate archives, especially sediment and

ice cores.

Objectives: After completing this exercise, your students should be able to:

1. Compare and contrast the temporal and spatial scope of tree ring, speleothem, glacial ice, lake sediment, marine sediment and sedimentary rock paleoclimate

archives.

2. Provide a rationale for which archive(s) would be best suited for different spatial and temporal constraints and scientific objectives.

3. Describe the 780,000 yr Owens Lake sedimentary record, including the methods of

age determination, the types of data collected, and a time-line interpretation made

of the paleoclimatic and environmental changes (both naturally caused and hu-man-influenced). This serves as a case study of the science that can be derived

from a paleoclimatic archive.

4. Identify the challenges and strategies for obtaining cores from glacial ice and the sub-sea floor.

5. Describe how ice and marine sediment samples are obtained and calculate the

costs involved,. 6. Explain why unique sample identification is essential and how that is achieved, as

well as, why reproducibility is important and how it can be achieved.

7. Calculate rates, including accumulation rates and explain how sample resolution is

affected by accumulation rates.

I. How Can I Use All or Parts of this Exercise in my Class? (based on Project 2061 instructional materials design.) Part 1.1 Part 1.2 Part 1.3

Title (of each part) Archives and Proxies

Owens Lake – An Introductory Case Study of Paleoclimate Reconstruction

Coring Glacial Ice and Seafloor Sediments

How much class time will I need? (per part)

40 min 40 min (not in-cluding reading assignment)

60 min

Can this be done inde-pendently (i.e., as home-work)?

Yes, with follow-up discussion

Yes Yes, with follow-up discussion

What content will students be introduced to in this exercise?

Research enabled by tech-nology

X X

How do you know about earth history? Types of archives

X X X

Where do you go to learn about earth history?

X X X

Judgment, decision-making, problem-solving

X X X


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What types of transportable skills will students practice in this exercise?

Make observations (describe what you see)

X X X

Interpret graphs, diagrams, photos, tables

X X

Make hypotheses or predic-tions

X X

Making persuasive, well- supported arguments

X X

Perform calculations (rates, averages, unit conversions) & develop quantitative skills

X

What general prerequisite knowledge & skills are required?

None required. Intro to processes of weathering and erosion may be helpful.

None.

What exercises (or parts of exercises) should be done prior to this to guide student interpretation & reasoning?

None None Part 1.1

What other resources or materials do I need? (e.g.,

internet access to show on-line video; access to maps, colored pencils)

None Access to the reading by

Menkin. See cita-tion in reference.

Internet access to watch on-line

video with audio and access the reading; calcula-tors

What student misconception does this exercise address?

Rocks on land are the only (or pri-mary) archives a geoscientist uses to interpret the past; age of sea-floor vs age of earth; ideas about resolution.

Human influence on environment is unproven

Scientists work in isolation (without a support network of engineers, tech-nicians, etc); glacial ice is only in high latitudes drilling the sea

floor is exclu-sively for oil.

What forms of data are used in this? (e.g., graphs, tables, photos, maps)

Photos, conceptual diagram, table, graph

Descriptive in reading

Photos, concep-tual diagrams, maps, numerical data

What geographic locations

are these datasets from?

Global Owens Lake,

California

Global ocean;

polar ice sheets

How can I use this exer-cise to identify my stu-dents’ prior knowledge (i.e., student misconcep-tions, commonly held be-

liefs)?

Part 1 introduces several concepts that are reinforced in Parts 2 and 3. Prior knowledge and misconceptions can be identified by examining student answers of open ended questions especially, and/or though class discussion.


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How can I encourage stu-dents to reflect on what they have learned in this exercise? [Formative As-sessment]

Exercise Parts can be concluded by asking: On note card (with or without name) to turn in, answer: What did you find most interesting/helpful in the exercise we did above? Does what we did model scientific practice? If so, how and if not, why not?

How can I assess student

learning after they com-plete all or part of the ex-ercise? [Summative As-sessment]

See suggestions in Summative Assessment section below.

Where can I go to for more information on the science

in this exercise?

See the Supplemental Materials and Reference sections below.

II. Annotated Student Worksheets (i.e., the ANSWER KEY)

This section includes the annotated copy of the student worksheets with answers for each Part of a chapter. This instructor guide contain the same sections as in the student book chapter, but also

includes additional information such as: useful tips, discussion points, notes on places where

students might get stuck, what specific points students should come away with from an

exercise so as to be prepared for further work, as well as ideas and/or material for mini-lectures.


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Part 1.1. Archives and Proxies

1 Think about how we know about past events in human history (e.g., the expansion of the Roman Empire, or the American Revolution). What types of records document these events?

e.g., diaries, historical written documents, maps, paintings

2 Now think about Earth’s history, specifically the past environmental or climatic conditions at times before recorded human history. What records might there be of such conditions? Make a list

of your ideas.

e.g., clues in the rock record; if students look at Figure 1.1 they may jump ahead and suggest tree rings, ice cores etc.

3 Figure 1.1 shows an assemblage of five major types of natural archive of Earth’s environmental

and climatic history. What common feature(s) do each of these paleoclimate archives share?

layers

The photographs in Figure 1.1 comprise an assemblage of five major types of natural records, or

archives, of Earth’s environmental and climatic history. Just like a diary or other historical

document, the layers in these natural archives contain indirect evidence (i.e., proxies) about past conditions and events, recorded in a sequential order. The evidence is specific to a certain time

period, and may be general or very detailed, depending on the rate that information was recorded.

The faster the rate at which the recorder grew (trees and corals), accumulated (snow and ice), or

was deposited (sedimentary sequences), the more detailed the record is and the higher its resolution. For example, a record in which an annual signal can observed has a very high reso-

lution. In contrast, if the finest observable details are on the order of a million years, that record

would have a low resolution. The usefulness of a record can be affected by how regularly information was recorded. If

information was recorded continuously the record would be more complete than if events were

recorded only occasionally.

4 Consider again each of the archives in Figure 1.1. Mark an “X” on each figure to indicate the

oldest part of the record. Explain your reasoning here:

In most cases, the oldest should be at the base (usually the bottom) or center, based on strati-

graphic principles, which the students may or may not be familiar, but logic may lead them to that same conclusion. The only exception is with stalactites, since these grow down from the cave

ceiling, the oldest (the base) is at the top. Based on the analogy of a pile of mail that has accu-

mulated on a desk, one could infer oldest at bottom for sediment, rocks, ice, and coral. For tree rings oldest is at the center of the tree; for cave deposits it depends on if a stalactite (oldest at top

because hang from cave ceiling) or stalagmite (in any case, youngest is at the end or tip). This is

an opportunity to draw out prior knowledge and identify misconceptions.


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5 Examine Figure 1.2. Place an “X” anywhere on the diagram where you would expect to find con-tinuously recorded (i.e., relatively uninterrupted) paleoclimate information. Explain your answer.

Students may recognize that sediments accumulate in low spots on Earth’s surface (both on land and in the ocean) as loose material is transported by water, wind, and ice, and deposited under the

influence of gravity. After a brief group discussion of their answers some additional explanation

about The Nature of the Sedimentary Record would be useful:

The chemical and physical weathering and erosion of the land creates terrigenous sediment

(e.g., gravel, sand, and mud; also called siliciclastic sediment). Terrigenous sediments are

transported by the power of wind, water, or ice and are then deposited under the influence of gravity in low places such as basins or valleys, and in areas that are nearly flat or have a very

gentle slope. Examples of such depositional environments include alluvial fans at the base of

mountains, alluvial plains in the valleys between mountain ranges, river valleys and floodplains, lakes and wetlands, coastal plains, estuaries, marshes, bays, river deltas, beaches, continental

shelves, deep sea fans at the base of continental slopes, abyssal plains, and deep sea trenches.

Biogenous sediment can also accumulate on the ocean floor and in lakes. For example, cal-careous sediments are produced by the abundant and diverse organisms and calcareous algae

that flourish in reef environments, tropical lagoons, and carbonate platforms, such as the Baha-

mas, shelf of western Florida, and the Great Barrier Reef off northeast Australia. Deep-sea cal-careous sediments are derived from the settling of calcareous plankton, including calcareous

nannofossils and planktic foraminifera, to the deep seafloor.

Unless sediments become buried and therefore protected from further erosion and transport, the

influence of gravity will tend to move material to deeper sites of deposition. For example, terri-

genous sediments are moved downstream by rivers where they might accumulate in floodplains

or deltas. Longshore currents move sediments along the coast, storms erode sediments along the shore and on the shelf, and then gravity moves sediments downslope to the deep sea by turbidity

currents. Biogenous sediments can also be eroded from shallow-water settings (such as reefs)

by storms and transported to the deep-sea by turbidity currents.

FIGURE 1.2. Major depositional systems. (Drawn by Lynn Fichter, James Madison University). A is an example outcrop setting, B1 is an example of a core in a marine (ocean) setting, B2 is an example of a core in a terrestrial (land) setting, B3 is an example of an ice core in a terrestrial (land) setting.


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Examine the photos of an outcrop, a marine sediment core, and an ice core (Figure 1.3). These could have originated from locations A, B1, and B3 respectively, in the block diagram (Figure

1.2).

6 How is the sedimentary outcrop similar to the sediment core? How are they different?

FIGURE 1.3. (A) Sedimentary outcrop from Bastrop, TX (courtesy of John Firth). (B) Photo of an Antarctic ice core (Courtesy of WAIS Divide Ice Core Project). It is approximately 9 cm wide. (C) A 104-cm long section of a marine core recovered from drilling the Pacific Ocean sea floor. The core is approximately 7 cm wide; it was originally a cylinder that was cut in half lengthwise (Shipboard Scientific Party, 2002b).

Outcrop and Core

Similarities

Outcrop and Core Dif-

ferences

See instructor notes below

See instructor notes below


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Students may recognize the layering in the outcrop and the core. Both the sediments in outcrops and the sediments in marine cores accumulate in layers to produce a sedimentary sequence.

These layers are like pages of a book. If a sedimentary sequence has certain characteristics, then it

may provide a useful archive of past environmental and climatic changes. The texture, sedimentary structures, composition, fossil content, geochemistry, and physical properties can be clues to what

the environment and climate were like at the time the sediment was accumulating at that location on

Earth.

There is a misconception among some students that outcrops, because they are exposed on land,

contain only sedimentary sequences originally deposited on land. This is not correct. Many outcrops

are in fact exposures of ancient marine sedimentary sequences. Changes in global sea level and/or plate tectonic driven uplift can result in the existence of ancient marine sedimentary sequences on

what is now land. Similarly some students are unaware that sedimentary sequences in marine cores

can tell us a great deal not only about past changes in the ocean environment, but also about past climatic conditions on land. This is in large part because terrestrial sediments are often transported

to the sea (see Fig. 1.2). In addition, the atmosphere-ocean systems are so interconnected that

investigations of the geochemistry of some calcareous sediments in marine cores can even tell us

what the atmospheric chemistry was like at the time the sediments were accumulating.

A distinct difference between outcrops and cores is the area available to be observed. Outcrops allow

geoscientists to view larger scale features than would a marine core. Coring along a transect and

obtaining seismic profiles between coring locations are ways to provide greater spatial dimension to interpret the sedimentary sequence in cores. Another difference between outcrops and cores is that

outcrops are exposed sedimentary sequences; outcrops are no longer places of sediment deposition,

but rather of sediment weathering and erosion. These processes of weathering and erosion can degrade the environmental and climatic record preserved in the sedimentary sequence, much like

altering or removing pages of a book would remove part of the story.

7 How are the two cores similar? How are they different?

Sediment and Ice Core Simi-larities

Sediment and Ice Core Dif-ferences

See instructor notes below See instructor notes below

These are similar in that they both display layers, representing the accumulation of material over time. The limited spatial representation is also similar. Both ice and sediment cores contain robust

records of past climate. Although, student may not be aware of this yet, the two types of archives

even contain some of the same proxies (e.g., stable oxygen isotope records, ash layers) that are

useful in reconstructing past climate. The two cores are certainly different in composition (ice vs. sediment), and depositional setting. And while they share some common proxies, there are other

very distinct differences in the clues they contain about past climate. For example, only ice cores

contain direct evidence of the composition of the paleo-atmosphere because of the trapped gas bubbles they can contain.


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The quality of the record can also be affected by what has happened to the archive since the initial recording. For example, sediments can be lithified into sedimentary rock; rock and sediment,

and the fossils they contain, can be weathered and eroded; ice can melt; and organic matter can

decay. All of these processes can degrade the information recorded and therefore increase un-certainty about the data and its interpretation. These processes also affect the maximum time

range that an archive is useful in paleoclimate reconstructions.

The various types of proxy data must be described and interpreted by those who have learned

how to “read” natural archives. This typically involves making observations and measurements using a wide range of analytical equipment (e.g., hand lens, microscopes, gas chromatographs,

mass spectrometers). While we rely on the various proxy data to reconstruct paleoclimates, it is

important to also recognize that each analytical method has its own limitations which can influence resolution, maximum time ranges, and scientific uncertainty.

Examine the data in Table 1.1 which summarizes the typical (exceptions certainly exist!) spatial

and temporal distribution of each of the paleoclimate archives in Figure 1.1. Also included in Table 1.1 are examples of the proxy data and climate parameters that can be reconstructed from these

archives. Supplemental information on each of these archives can be found on the web-

site associated with this book. In Table 1.1 notice that lake sediments, marine sediments, and

sedimentary rocks, while they are all sedimentary sequences, are displayed in separate rows in this table because of their distinctly different timeframes and resolutions.

8 The oldest sediments in the modern ocean are approximately 200 million years old. What im-

plication does this have for learning about ocean conditions prior to 200 million ago?

This should get at prior knowledge of plate tectonics, but student answers may also bring up

limitations on dating techniques. There are no older sediments in the modern ocean because they have been subducted.

If we want to learn about past ocean conditions for the Mesozoic and earlier, we must turn to

marine sequences that were uplifted (e.g., caught up in mountain building) or otherwise exposed on land. For example, global sea level fall helped expose ancient shallow epicontinental seas (e.g.,

the Cretaceous interior seaway) in the western interior United States.

An extension to this topic may be asking: how do we know about the earliest history of the Earth if

the oldest meta-sedimentary rocks are ~3.6 billion years old? We infer information about the

earliest time of Earth history from other solar system material – meteorites. In addition, “recycled”

zircon minerals in NW Canada have been dated to 4.4 byr (Wilde et al, 2001, Nature).


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TABLE 1.1. Selected major paleoclimate archives and their proxies*

Archive Geographic

Distribution;

Approximate

Number of

Sites Sampled

Time Range

of the

Majority of

the Records

(years before

present)

Resolu-

tion

(years)

Types of Material

Analyzed and/or Data

Collected

Climate

Parameters

Continental

Tree Rings Global, but most

sites in the

northern hemi-

sphere; 1000s

<10,000 <1 Cellulose;

isotopes;

ring widths

Seasonal precipitation

and temperature

Lake

Sediments

Global, but most

sites in the

northern hemi-

sphere; appx.

100s

<1,000,000 1–20 Microfossil (flora and

fauna) types and abun-

dances; stable isotopes;

trace elements; al-

kenone biomarkers;

sediment composition

and geochemistry.

Regional changes in

precipitation and

evaporation; tem-

perature; salinity;

volcanic activity; gla-

cial activity

Speleo-

thems

(cave

deposits)

Global, but most

sites in the

northern hemi-

sphere; appx. 50

<500,000 1–2000 Stable isotopes; trace

elements

Temperature; pre-

cipitation, atmos-

pheric CO2

Ice Sheets

and

Glaciers

Polar ice sheets,

and high altitude

(alpine) temper-

ate and tropical

glaciers; appx.

80

<800,000 <1–1000 Stable isotopes; trace

elements; dust and other

particulates; atmos-

pheric gas concentra-

tions

Temperature; pre-

cipitation;

wind/atmospheric cir-

culation; atmospheric

chemistry; volcanic

activity; biomass

burning

Sedimen-

tary Rocks

Global; tens of

thousands

<3,600,000,000 10,000–

100,000

Microfossil (flora and

fauna) types and abun-

dances; sediment compo-

sition; stable isotopes;

depositional patterns

Temperature; biologi-

cal productivity; vol-

canic activity; glacial

activity; sea level; ice

volume; evolution

Oceanic

Corals Tropical and

subtropical

oceans, appx. 60

<650,000 <1–1000 Stable isotopes; trace

elements

Salinity; temperature;

nutrients; sea level;

ice volume

Marine

Sediments

Global; 65,000 <200,000,000 100–

1000

Microfossil (flora and

fauna) types and

abundances; stable

isotopes; trace ele-

ments; alkenone bio-

markers; sediment

composition; deposi-

tional patterns

Ocean & atmospheric

circulation; tempera-

ture; salinity; nutri-

ents; aridity on land;

biological productivity;

volcanic activity; gla-

cial activity; ice volume


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* Adapted from Cronin (1999) with information from Ruddiman (2008), http://www.ncdc.noaa.gov/paleo/, and http://www.ngdc.noaa.gov/mgg/curator/curator.html.

9 Which archive has the widest geographic distribution, and the greatest number of sites sampled?

Marine sediments – however this should be qualified by noting most marine cores are <1 m in length; the value of longer cores will be demonstrated in subsequent exercises.

Students may also answer- continental sedimentary rocks (outcrops and cores). However, the

number of sedimentary rock sites is difficult to determine since no database exists for this broad

archive.

NOTE: In addition to making sure students understand information in Table 1.1, the next series of questions (10-15) can be used to introduce the benefits of a multi-proxy, multi-archive approach, as

well as regional vs global geographic distribution of records.

10 Examine Figure 1.4, showing the distribution of human population vs. latitude. What latitudes are

the most densely populated?

20-40º North

FIGURE 1.4. Latitudinal distribution of the 1990 human population. From Li, 1996.

11 Propose likely physical and historical factors that underline the pattern in Figure 1.4.

Reflects the densely populated Northern Hemisphere continents of Europe, Asia, and North America. Southern hemisphere is ocean dominated. Polar latitudes less hospitable climates.

http://www.ncdc.noaa.gov/paleo/

http://www.ngdc.noaa.gov/mgg/curator/curator.html


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12 How might the human population distribution (Figure 1.4) influence the geographic distribu-

tion of paleoclimate research sites? Use the summary data in Table 1.1 to support your hypothesis.

For several continental archives there are currently more sites in the Northern Hemisphere. A reasonable

hypothesis may be that people do research in areas they are familiar with. In addition the cost may be

less if the distance is smaller.

13 Imagine you have to reconstruct regional environmental and climatic conditions for the last

100,000 years in Europe as completely as possible. Which archive(s) would you choose to use and

why?

Regional records in Europe and surrounding oceans from all archives, except sedimentary rocks due to the relatively young time range of interest.

14 Imagine you have to reconstruct the global history of Earth’s environmental and climatic

conditions for the last 5 million years as completely as possible. Which archive(s) would you choose to use and why?

To get a global record we would want a global distribution of sites. While all archives could provide

data for the last 0.5-1 million years, the rest of the reconstruction would need to rely on marine sediments and sedimentary rocks. For example, known ice core records do not extend beyond

800,000 years, and very few pre-Pleistocene lake and speleothem records exist.

15 Imagine you have to reconstruct the global history of environmental and climatic conditions of

the Cretaceous period (145–66 Ma ago). What archive(s) would you choose to use and why?

Again, to get a global record we would want a global distribution of sites. While all archives could

provide data for the last 0.5-1 million years, the rest of the reconstruction would need to rely on

marine sediments and sedimentary rocks.


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Part 1.2. Owens Lake – An Introductory Case Study of Paleoclimate

Reconstruction

In Part 1.1 you were introduced to the range of archives and proxies of past climate change. In Part

1.2, the Owens Lake, CA sediment record will serve as an introductory paleoclimate case study;

you will describe and interpret the clues that this archive and its proxies can offer us about climate in western North America over the last 800,000 years.

Note: For copyright reasons we are not able to reproduce the Menking (2000) book chapter and make it available as an online supplement. We have found that this is a great supplemental reading

for students to introduce cores, stratigraphy, and proxies, and age dating methods. Having stu-

dents sketch and interpret the descriptive data in the reading helps students construct their un-

derstanding about these concepts. Plus it is a really interesting!

1 Use your library resources to find and read the following reference: Menking, K.M., 2000, A record

of climate change from Owens Lake sediment, in Schneiderman, J.S. (ed.), The Earth Around Us: Maintaining a Livable Planet, New York: W.H. Freeman and Company, p. 322–335. Use the work

space at the end of Part 1.2 to (a) make a visual representation (a sketch) of the Owens Lake

sediment core. Use different patterns or colors to represent the different layers described in the article, with the oldest at the bottom and the youngest at the top. (b) Adjacent to your sketch, list

the types of proxy data (e.g., salt layer, pebbles, ash, microfossils,...) obtained from the dif-

ferent intervals of the core. (c) Next to the list of proxies, give an interpretation of the data with

respect to past climatic and/or environmental conditions (e.g., dry, cold, volcanic eruption,...).

An example of student work [permission granted] is shown below. The blank workspace for student

work is at the end of Part 1.2.


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2 What methods were used to determine age within the core?

Radiocarbon dating, biostratigraphy, magnetostratigraphy, and tephrachronology

3 What evidence is there that part of the Owens Lake record is missing (i.e., that a hiatus exists)?

What could cause this?

The radiocarbon dates indicate a 3000 year jump in age between a dark mud with dropstones and the overlying oolitic layer. Therefore, both the radiocarbon dates and the abrupt change in lithology

suggest that a hiatus exists.

C-14 age 8300 yrs

C-14 age 5100 yrs

No record for ~3000 yrs. Maybe the lake dried up and wind eroded the dry lake layer?


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4 What evidence would support the hypothesis that humans impacted the environment in and/or

around Owens Lake?

The better answer is that the lake is dry, containing a salt crust at the top. This coincides with the

draining of the lake to supply the city of Los Angeles with water in the early 1900s, as described in

the reading. Some students may answer more broadly about global warming, which the article also discusses.

5 Use Owens Lake to explain why a multiproxy approach is valuable in reconstructing past climatic

and/or environmental change:

Each type of proxy provides one type of evidence for reconstructing the past; combining infor-mation from different proxies will provide more complete evidence. For example, if only the li-

thology was used for Owens Lake, we would know about lake level changes and about the existence

of glaciers, but we would not be able to infer temperature as well as can be done with the addition of the microfossil and pollen data.

Workspace for Question 1:

Sketch of Core

Type of Data Analyzed Paleoclimatic/Environmental Interpretation

Two examples are

provided immedi-

ately after question

1. Students are provided a full page

for their answer. The

workspace was shortened in the

instructor guide sim-

ply for space considerations.


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Part 1.3. Coring Glacial Ice and Seafloor Sediments

Coring allows scientists to access a sequence of climatic and environmental conditions (i.e., a history) locked away in natural archives. Trees, corals, sediments, rock, and ice are all cored for

paleoclimatic studies. Cores are narrow, cylindrical samples that extend through layer after layer

of the material being investigated. Tree cores are thinnest, only approximately 0.5 cm diameter and 50 cm long. Coral, sediment, rock, and ice cores are often a few centimeters in diameter and

of variable length ( 50 cm to 10 m), depending on the coring technology used, the thickness of the

material being cored, and the objectives of the study. Repeated drilling in the same hole can re-cover many successive meters of core from successively greater depths (Figure 1.5). The deepest

cored hole in glacial ice (EPICA Dome C) is over 3.2 km deep and is located on the high polar

plateau in East Antarctica. The deepest cored hole in the seafloor (Hole 504B) is over 2.1 km deep

and is located in the eastern equatorial Pacific Ocean, on the Costa Rica Rift. This deep-sea drill site penetrated through the sedimentary layers and into the underlying igneous ocean crust.

FIGURE 1.5. Example of (left) an ice core from Huascaran, Peru (Courtesy of Lonnie Thompson), and (right) a sediment core from the western equatorial Pacific Ocean (Courtesy of Mark Leckie).

In this exercise you will investigate how cores are obtained from arguably the most technologically challenging paleoclimate archives: glacial ice and seafloor sediments. We will also use these ar-

chives to explore issues common to all types of paleoclimate research: the need for teamwork,

methods that keep samples uncontaminated and organized, reproducible results, and funding.


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Coring Glacial Ice

1 Where does glacial ice (i.e., glaciers, ice sheets) exist today?

This reinforces something students were introduced to in Part 1, Table 1.1: glacial ice exists in polar

regions (all elevations) and in temperate and tropical regions at increasingly higher elevations; the

latter is also referred to as alpine ice or alpine glaciers.

2 Watch the two on-line videos and read the short news article to gain an appreciation of the ice core

drilling process. Then make a list of the challenges of obtaining ice cores for paleoclimate research.

How do scientists and engineers overcome these challenges? 2-minute video on southern Alps ice core drilling:

http://www.youtube.com/watch?v=T69_diWYbkQ

5-minute video on Antarctic ice core drilling: http://www.youtube.com/watch?v=kdfcNIFEnF8

2-page news article (Stone, May 28, 2010, Arduous Expedition to Sample Last Virgin Tropical Glaciers, Science, vol. 328, p. 1084-1085) on the New Guinea ice core drilling:

http://www.sciencemag.org/cgi/content/short/328/5982/1084 (Note that students will need

to use their library resources to access this article.)

Challenges Solutions

Temperature Protective gear, do field work during summer months

Altitude Training

Remote setting International cooperation, funding

Transportation of ice cores Well insulated containers, need to transport quickly (esp. If

coring in tropical locations)

Cost and logistics Cooperation with multiple agencies, shared funding; taxes

Lower latitude glaciers

melting

Do research now, before

archives disappear

Contamination from modern

atmosphere

Store quickly, sample inner part of core, keep ice from

melting (next question related to this too)

Bubbles of ancient air (Figure 1.6) found in glacial ice are unique and valuable indicators of past

climate. Unlike most other climate indicators, which indirectly record climate parameters, the

trapped air in glacial ice is a direct measure of atmospheric gases (e.g., CO2 and CH4) of the past.

As snow recrystallizes into ice below the surface of a glacier, air is trapped in the pore spaces between ice crystals. The pore spaces are eventually closed off from the atmosphere by continued

accumulation of new snow and by the recrystallization and fusing of individual ice crystals from

layers of snow to firn (compacted snow) to ice. Because the pore spaces are open to the at-mosphere until the ice forms, the age of the gases in the pore spaces is younger than the sur-

rounding ice. Trapped gas comprises 10–15% of the volume of glacial ice at the “bubble close off


http://www.youtube.com/watch?v=kdfcNIFEnF8

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depth” (firn-ice transition) (Bender et al., 1997).

FIGURE 1.6. Piece of an Antarctic ice showing trapped air bubbles (Courtesy of Edward Brooke, Oregon State University).

FIGURE 1.7. Class 100 clean room at Bryd Polar Research Center. Class 100 means there are less than 100 particles (diameter >0.5 µm) per cubic foot of air. Photo courtesy of Ellen Mosley-Thompson and the Byrd Polar Research Center.

Examine Figure 1.7, which shows a lab where ice cores samples are analyzed, and read the following brief description of the sample preparation and gas analysis process:

Ice samples were cut with a band saw in a cold room (at about −15 °C) as close as possible to

the center of the core in order to avoid surface contamination. Gas extraction and meas-

urements were performed by crushing the ice sample (approximately 40 g) under vacuum in a stainless steel container without melting it, expanding the gas released during the crushing in

a pre-evacuated sampling loop, and analyzing the CO2 concentrations by gas chromatography.

The analytical system, except for the stainless steel container in which the ice was crushed, was calibrated for each ice sample measurement with a standard mixture of CO2 in nitrogen

and oxygen. Text is modified from: http://cdiac.ornl.gov/trends/co2/vostok.html

http://cdiac.ornl.gov/trends/co2/vostok.html


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3 Identify some specific conditions and methods from the above description and propose why they are necessary to produce robust gas concentration data from the ice core.

The cold temperature would help keep ice from melting. The vacuum would help keep the sample

isolated from the modern atmosphere. The clean lab would help keep dust particles from poten-tially coming in contact with the samples.

4 There are hundreds of analytical labs around the world that are capable of measuring CO2 and CH4

gas concentrations from ice core samples. How could investigators ensure that the results from

different labs are comparable?

To ensure reproducibility different labs would need to follow similar analytical procedures and,

more importantly, the different labs would need to calibrate their instrumentation using a common

standard (see inset paragraph above). They may also analyze replicate samples of ice from the same layers in order to demonstrate reproducibility of the results.

5 In 1992, the European Greenland Ice Core Project (GRIP) drilled down 3029 m to the base of the

Greenland ice sheet at Summit, Greenland (72°N, 38°W). A year later the US Greenland Ice Sheet Project 2 (GISP2) completed drilling of a companion record through the ice sheet 30 km to the west.

What value might there be in obtaining two parallel ice core records so close together?

The redundancy of records allows scientists to compare stratigraphies and look for hiatuses, to help

determine if the records are continuous or if they are disturbed or are missing sections. Comparing the geographic variability of the records can also help us distinguish local vs. regional vs. global

scales of change. Replication of results improves the accuracy of the results and reduces uncer-

tainty in interpretation. Note that the small diameter of the cores and the lack of any reliable “up” indicators in ice prevents scientists from easily recognizing overturned stratigraphy (Alley et al.,

1995). The paleoclimate timelines of these two ice cores were found to be nearly identical for the

last 110,000 yrs, but ice flow disturbance in the deeper part of the cores obscured the older rec-ords.

6 The upper 2788 m of the GRIP ice core contain a Greenland paleoclimate record of the last 110,000

years. The European Project for Ice Coring in Antarctica (EPICA) recovered the deepest and oldest

ice record to date at Dome C, Antarctica. This 3270.2 m-long ice core contains a paleoclimate record of the last 740,000 years.

(a) Calculate the average ice accumulation rates (cm/yr) for the GRIP and EPICA ice cores. Show your

work, including the conversion from meters to centimeters.

GRIP: 2788m/110,000yrs = 0.025 m/yr = 2.5 cm/yr

EPICA: 3270.2m/740,000 yrs = 0.004 m/yr = 0.4 cm/yr

(b) Which has a higher average ice accumulation rate: GRIP or EPICA? GRIP


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(c) Which has a higher average resolution, GRIP or EPICA?

The GRIP (Summit, Greenland) core has higher resolution than the EPICA (Dome C, Antarctica)

core.

(d) Which record spans a greater period of Earth history, GRIP or EPICA?

The EPICA core provides a timeline that covers 7X more of Earth’s paleoclimatic history than does

the GRIP core.

Coring Ocean Sediments The JOIDES Resolution (Figure 1.8) is designed to obtain core from below the seafloor. Use the

online resources at http://joidesresolution.org to learn about this ship. In particular, take a virtual tour of the ship by selecting Meet the JR and then Research Vessel Tour. Learn about the

drilling process by selecting Multimedia and watching the three-minute video “An Explanation

of Deep Sea Coring”.

7 How are vessels used for scientific ocean drilling specially outfitted to enable them to recover cores

from below the seafloor?

FIGURE 1.8. Scientific research vessel, JOIDES Resolution. Courtesy of Bill Crawford, IODP Expedition 321.

Unlike outcrops, scientists cannot walk up to marine coring sites. Obtaining marine cores is an

expensive and technologically-dependent endeavor. Coring requires a special drilling vessel and

coring system. The ship’s captain and crew, the drilling engineers and their crews, and the marine technicians all contribute to the success of the coring operation.

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The JOIDES Resolution is a 471-ft long drill ship that uses a computerized dynamic positioning system to control 12 propulsion thrusters around the ship. These thrusters keep the ship in position

over a specific seafloor location while drilling proceeds. Drilling to a total depth (water depth plus

depth into the seafloor) of 27,500 ft (8386 m) is possible, in water depths ranging from 75 to >6000 m. The ship is equipped with laboratories for shipboard processing and analysis of cores and

borehole logging data. The 147 ft (44.8 m) tall derrick houses a top drive drilling system; drill

pipe is attached from it down to the seafloor through an open moon pool (opening in the hull) in the

center of the ship. Heave compensator systems permit drilling/coring with ship heave from waves of up to 16 ft (4.9 m). The vessel can maintain position within 3% of water depth in up to 7.5 m (25

ft) waves, 60 knot (kt) winds, and 3.0 kt currents. (Text adapted and modified from Graber et al.,

2002)

Coring into the seafloor occurs in 9.5-m-long intervals, corresponding to the length of the core

barrel that fits within the hollow steel drill pipe and locks into a position above the drill bit. A typical

drill bit has 4 roller cones that surround a central open cylinder. As the drill pipe is turned, the drill bit cuts a cylinder of sediment or rock that slides past the bit and into the core barrel. Inside the core

barrel is a clear plastic core liner containing the cylinder of sediment or rock cut by the drill bit or

other coring device (e.g., hydraulic piston corer, advanced piston corer). After a 9.5-m core has

been cut, a cable is lowered down the inside of the drill pipe. The cable latches onto the top of the core barrel, which is then pulled up to the drill floor and extracted from the drill pipe by the drilling

crew (referred to as roughnecks). The core barrel is laid on its side and the core-catcher is re-

moved from the bottom of the core barrel (the core-catcher prevents the sediment or rock from slipping out of the core liner as the core barrel is lifted up through the drill pipe). The drilling crew

pulls the core liner out of the core barrel. A group of marine technicians then carries the nearly

10-m long core liner filled with sediment (hopefully filled with something other than seawater!) and lays it out on a special rack on the catwalk, which is a platform located outside the core laboratory.

The techs then measure the core from the top and mark it off in 1.5-m (150 cm) sections. As each

section is cut, it is labeled and an end-cap is affixed to both ends (a blue end-cap for the top and a

clear end-cap for the bottom).

The 1.5-m sections are brought into the lab and placed in racks for at least 4 hours so that they can

thermally equilibrate with surface temperatures. After 4 hours, the cores are run through the Multi

Sensor Core Logger (MSCL) to collect an array of non-destructive data (gamma ray, magnetic susceptibility). Then the cores are split longitudinally into two halves; the working half, which is

used to collect discrete samples (e.g., physical properties, paleomagnetics, inorganic and organic

geochemistry, micropaleontology), and the archive half, which is used for non-destructive analyses

(e.g., core description, color reflectance, color scanning, paleomagnetics), and core photography.


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FIGURE 1.9. Scientific ocean drilling site locations of the Integrated Ocean Drilling Program (IODP; 2003–2013) and predecessor programs, the Ocean Drilling Program (ODP; 1983–2003) and the Deep Sea Drilling Project (DSDP; 1968–1983). Map courtesy of IODP.

The map above (Figure 1.9) shows all of the drill site locations from the over 40 year history of

scientific ocean drilling expeditions. At each of these drill site locations several holes may have been drilled and tens to hundreds of 9.5-m length cores recovered. To carry and store the cores

more easily, each is cut into 1.5-meter sections (Figures 1.5 & 1.10). The core sections are also

split lengthwise into a two halves – a working half, which is used in sampling, and an archive

half, which is used for non-destructive analyses and for core photography (Figure 1.11). In total there are currently >40,000 m of core recovered from below the seafloor and >2.3 million samples

taken of the core sections in specific centimeter intervals. To keep so many samples organized for

scientific research it is important that each sample has a unique and meaningful identification code.

8 The challenge of assigning unique identification codes to scientific samples is analogous to the

challenge that libraries have in organizing and categorizing books. The US Library of Congress is

the largest library in the world, with millions of books, recordings, photographs, maps, and manuscripts in its collections. Look up your favorite book in the US Library of Congress website

(http://catalog.loc.gov/). What unique identification code distinguishes your book from all of the

other books in the library?

Books are identified by their call numbers and/or by their ISBN numbers.

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FIGURE 1.10. Example of coring and core terminology. Shipboard Scientific Party, 2002a.

FIGURE 1.11. Photo of the archive-half of Core 2 from Hole 1215A, located in the central tropical Pacific Ocean. The sections of core are laid out next to each other, left to right. Section 1 of Core 2 is at the top of the drilled interval and the core catcher (CC) is at the bottom of the cored interval. The shipboard paleontologists took a sample (PAL) from the base of the core catcher to provide a preliminary age determination for Core 2. Site 1215 was cored during Ocean Drilling Program Leg (i.e., Expedition) 199. Note that an interstitial water sample (IW) was taken from the bottom of Section 3. Courtesy of IODP.

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9 Think about marine core samples. How could you ensure that each sample had a unique identi-fication so that you knew exactly where in the sub-seafloor it came from? List your ideas.

To ensure unique sample identification for each sample and so that the sample is linked back to a specific sub-seafloor location each sample has a unique identification number. This number is long

and includes the following: expedition, site, hole, core number, core type, section number, and

interval in centimeters measured from the top of that section. For example, “210-1276A-3R-3,

80–85 cm” is a sample from the interval 80 to 85 cm below the top of Section 3, Core 3R of Hole 1276A during Leg 210. All IODP and ODP core identifiers indicate core type (R = rotary core barrel,

H = advanced piston corer, X = extended core barrel, and W = wash core).

Cored intervals can also be described in meters below sea floor (mbsf). The mbsf depth of a sample

is determined by adding the depth of the sample below the section top and the lengths of all higher

sections in the core to the core-top datum measured with the drill string. (Text adapted and

modified from Whitman, 2005).

Unique identification of a sample is important because scientific analyses of that sample are really

most useful if they are in a geographic and geologic context. Knowing the location, the sub-seafloor depth, and the age of the sample enable temporal and spatial comparisons and correlations to be

made, none of which could be done if there was any uncertainty of the origin of a particular sample.

Unique identifiers also allow several samples from the same level in a core to be analyzed inde-pendently and compared later. The reproducibility of results is an important part of the scientific

method.

10 The standard labelling for ocean drilling samples is shown in Figure 1.10.

(a) Deconstruct the sample identification “199-1215A-2H-5, 80-85” by filling in the blanks below: Leg (or Expedition)_199_ Site_1215_ Hole_A_ Core_2(H)_ Section_5_ Centimeter interval_80-85_.

(b) Place an X on Figure 1.11 marking the location of this sample. See figure

Science requires both qualitative skills and quantitative skills. In questions 11–15 you will

quantify some of the costs (with respect to time and money) involved in obtaining sediment cores

from below the seafloor.

11 Expedition (Leg) 199 began in Honolulu, Hawaii on October 28, 2001. The JOIDES Resolution

left port at 0830 hr on 28 October and transited 1158 km to the first drilling location, Site 1215,

arriving at 2100 hr on 30 October, 2001. What was the average rate of travel (i.e., speed) during

transit in km/hr? Convert this value to miles/hr. Show your work, including conversion.

1158 km/60.5hr = 19.14 km/hr = 11.9 mi/hr

Note that the actual operational data used for this question was reported in nautical units (nmi and

knots), and can be accessed here: http://www-odp.tamu.edu/publications/prelim/199_prel/prel20.html.

http://www-odp.tamu.edu/publications/prelim/199_prel/prel20.html


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12 Site 1215 was planned for 57.5 hr of drilling during Expedition 199. During this time the crew

were able to drill 75.4 m below the seafloor at a single location (Hole 1215A). What was the av-erage drilling rate (m/hr) for Hole 1215A? Show your work.

75.4 m / 57.5 hrs = 1.3 m/hr

13 While the crew drilled 75.4 m below the seafloor at Hole 1215A, they only recovered 68.27 m of core. What was the percent core recovery for Hole 1215A? Propose a hypothesis to explain why

core recovery would be less than the maximum drill depth.

68.27 m / 75.4 m = 0.905 x 100 = 90.5% core recovery.

The coring process can be destructive to some types of unconsolidated sediment. When this occurs the core barrel will not be full, as sediment will “wash out” during the drilling process producing

voids in the core barrel. Different coring tools and drilling techniques are used to maximize the

core recovery. For more information on these coring tools see: http://iodp.tamu.edu/tools/.

Note, sometimes core recovery is >100%! This can happen when soft sediment that is gas-rich is

“depressurized” as it is brought to the surface and it expands. Sediment expansion can also occur

from clay swelling. For information on how core recover is accounted for when estimating depth below seafloor, see Piper and Flood (1997).

14 A typical ocean drilling expedition lasts around 60 days and costs approximately US $6 million.

At Hole 1215A on ODP Leg 199, 68.74–m of core were obtained during 57.5 hours drilling. What is

the cost of 1–m of core from Hole 1215A? Show your work.

This is a multi-step solution:

2 months = ~60 days so $6 million / 60 days = $100,000/day

$100,000 / 24 hours = $X /57.5 hours

X = $239,583 so Hole 1215A costs $239,583 to drill.

$239,583 / 68.74 meters = $Y /1 meter

Y = $3485 so 1 meter of core at Hole 1215A has a cost (value) of $3485

This number may surprise students; the value of 1 meter of core is quite high. A logical question

students may have is “At that price, what can 1 meter of core get you?” The answer is A LOT

scientifically. The suite of exercises that follow (e.g., Seafloor Sediments, Marine Microfossils,

Climate Cycles, PETM) are all avenues for your students to actively explore the scientific value of ocean drilling.

15 Sometimes scientific ocean drilling and NASA space exploration are compared because these

are both large-scale, technologically dependent programs that are designed to help teams of scientists unravel the history of the Earth and our solar system by exploring in remote and

challenging settings. Compare the cost of obtaining core from the seafloor to the cost of obtaining

rocks from the moon in the following.

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(a) The Apollo 11 mission cost US$355 million in 1969. Approximately 21.8 kg of moon rock were

obtained on this successful and historic mission to the moon. What was the cost of 1 kg of moon rock in 1969? Show your work.

$355 million / 21.8 kg = $ X million / 1 kg

X = $16,284,403/kg so 1 kg of moon rock has a cost of over $16 million in 1969.

(b) The cost of a seafloor core that you calculated in question 14 was the cost per meter of core.

To make a comparison to the cost of the moon rock we need to determine the cost per kg of core

(so we will need to convert units). Use your skills in geometry to work this out; the average density

of cores from Hole 1215A is approximately 1.3 g/cm3. The core is a cylinder with a radius of 3.5 cm and a length (or height) of 1 m (100 cm). The volume of a cylinder is equal to πr2h. Recall from

question 14 that a scientific ocean drilling expedition is typically 60 days and costs approximately

US$6 million. What is the cost of 1 kg of core? How does this compare to the cost of 1 kg of moon rock?

This is a multi-step solution:

To determine the volume of 1 meter of core:

V=∏r2h = 3.142 x (3.5 cm)2 x 100 cm = 3849 cm3

To determine the average mass of 1 meter of core:

1.3g/cm3 x 3849 cm3 = 5004 g = 5.004 kg (round to 5 kg)

To determine the cost of 1 kg of core students combine their answer from question 14 with this new information:

$3485 / 5 kg = $X / 1 kg

X = $697/kg

Thus, the cost of 1 kg of seafloor core, while high ($697/kg), is considerably less that the cost of

obtaining 1 kg of moon rock ($16,284,403/kg). Both have tremendous scientific value.

16 In this book we will emphasize how and what we know about climate change in the Cenozoic

Era (the most recent 65.5 million years of Earth’s history). Consequently, the primary archive we will draw from is the ocean sediment record; it will be supplemented by data from other archives,

especially the ice core record, depending on the particular timeframe and/or climatic event in-

troduced. Go to http://recordings.wun.ac.uk/conf/nwo/oceandrilling2006 and select the 5-minute video titled “Why Ocean Drilling?” Based on this video and what you have learned in this ex-

ercise, list the benefits and limitations of utilizing the ocean sediment record to reconstruct Ce-

nozoic climate change.

This video makes a strong case for why marine cores are so useful in reconstructing Earth’s climate history.

Benefits: the opportunity for a wide geographic distribution of sample sets; a more continuous and

longer record than many continental archives; several proxies that can provide information about

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ocean, atmosphere, and continental changes over time; multiple opportunities for age-dating (al-though this concept is not directly introduced here, it will be addressed in later exercises).

Limitations: not as high a resolution as lake records, ice cores, and corals; costly and technologically

difficult to obtain records; in some locations the records may not be continuous (can contain hia-tuses)

About Marine vs Terrestrial Sedimentary Archives of Climate Change

The sedimentary record on land is often incomplete due to punctuated sedimentation in many

terrestrial environments (i.e., sedimentation is not continuous due to episodic deposition and erosion). It is often the infrequent events that result in pulses of sediment accumulation and

burial to the rock record. Examples include storms, floods, extreme weather events, land slides

and slumps, and seismic or volcanic activity. These conditions are responsible for both erosion and deposition of sediment.

Terrestrial environments are exposed to the processes of erosion, including chemical

weathering due to dissolution by acidic rains and physical weathering due to freeze-thaw and the action of wind, water, and ice.

Difficulty dating land-based sections; why?: many terrestrial environments lack adequate

fossil control for dating; often due to poor fossil preservation or low fossil abundance; not all

fossils are useful for dating, although they may be diagnostic of past environmental conditions, including climate.

Fewer geochemical proxies available due to paucity of fossils in many terrestrial environ-

ments.

Advantages of marine sedimentary records:

Thicker, more complete sedimentary records

Fossiliferous sediments allow relative dating and correlation to other areas, and they provide geochemical proxies for studies of past ocean-climate change.

Long records can be cored that represent many tens of millions of years.

High resolution records can be cored in areas of high sedimentation rate, such as continental

margins and sediment drifts.

There are problems with marine sedimentary records as well:

Some sequences are incomplete due to erosion by deep sea currents, non-deposition, dis-

solution of carbonate, undersea slumps, and inadequate sediment supply,

Sedimentary sequences on or near slopes can be affected by gravity slides and displaced

sedimentary sequence.

Turbidites and redeposited sediments from upslope yield mixed fossil assemblages of different

ages and paleoenvironments.

Marine sediment records may be deposited far from important processes/conditions on land

and therefore may be subject to multiple controls. This makes it challenging to decipher the

history of those processes/conditions.


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III. Summative Assessment

The following questions could be used to assess student learning after completing this exercise:

1. What is one characteristic that the following archives share: trees, corals, speleothems, sedi-

mentary sequences, and ice?

2. Summarize the characteristics that would make an archive (or record) useful for reconstructing

Earth’s past environmental and climatic change.

3. List two advantages of using sedimentary sequences from marine cores in reconstructing

Earth’s past environmental and climatic changes.

4. Compare and contrast the challenges of ob-

taining glacial ice cores and sub-seafloor sediment

cores.

5. The Antarctica Ice sheet has a lower ice accu-

mulation rate than the Greenland Ice Sheet. How

would this influence the resolution and maximum

time range represented by ice cores from these

two locations?

6. Why is reproducibility of results important in

science?

7. What are two strategies for avoiding contami-

nation of ice core samples?

8. What would the complete sample identifica-

tion be for the interstitial water (IW) sample

shown in the core photo (right)?

a. 198-1209A-2H-4, 145-150 cm

b. 198-1209A-2H-145

c. 2H-A-1209-198-4-145-150

d. core 2H, section 4, 145-150 cm

IV. Supplemental Materials

For a review of the range and reliability of paleoclimate data see: White, J., Molfino, B.,

Labeyrie, L., Stauffer, B., and Farquhar, G., 1993. How Reliable and Consistent are Paleodata

from Continents, Oceans, and Ice? In Eddy, J.A., and Oeschger, H. (eds.), Global Changes in

the Perspective of the Past, John Wiley and Sons, p. 73-102. For a general overview of tropical ice cores see: Thompson, L.G., 2000. Ice core evidence for


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climate change in the Tropics: implications for our future, Quaternary Science Reviews, 19,

19-35.

For datasets from trees, ice cores, corals, lacustrine sediments, marine sediments, and

speleothems go to the NOAA Paleoclimatology database: http://www.ncdc.noaa.gov/paleo/ For an index of lacustrine and marine samples go to the National Geophysical Data Center:

http://www.ngdc.noaa.gov/mgg/curator/curator.html The Owens Lake reading associated with Part 2 is: Menking, K.M., 2000, A record of climate

change from Owens Lake sediment, in Schneiderman, J.S. (ed.), The Earth Around Us:

Maintaining a Livable Planet, New York: W.H. Freeman and Company, p. 322-335. For a scientific overview of the Owen’s Lake record see: Smith, G. I., and Bischoff, J.L., 1997,

Core OL-92 from Owens Lake: Project rationale, geologic setting, drilling procedures, and

summary, in Smith, G. I. and Bischoff, J. L. (eds.), An 800,000-year paleoclimatic Record ftom

Core OL-92, Owens Lake, Southeast California. Geological Society of America Special Paper

317, Boulder, Colorado, p. 1-8.

The following are ice core resources that students are directed to in this exercise: (a) a

2-minute video on southern Alps ice core drilling:

http://www.youtube.com/watch?v=T69_diWYbkQ; a 5-minute video on Antarctic ice core

drilling: http://www.youtube.com/watch?v=kdfcNIFEnF8; a 2-page news article (Stone, May

28, 2010, Arduous Expedition to Sample Last Virgin Tropical Glaciers, Science, vol. 328, p.

1084-1085) on the New Guinea ice core drilling:

http://www.sciencemag.org/cgi/content/short/328/5982/1084 For comparisons and summaries of the GRIP and GISP2 ice core projects in Greenland see:

White, J.W.C., 2004. Do I hear a million? Science, 304, 1609-1610; and Dansgaard, W., et al.,

1993. Evidence of general instability of past climate from a 250-kyr ice core record, Nature,

364, p. 218-220. For a profile of a paleoclimatologist see the 11 min NOVA video documentary on Lonnie

Thompson and his tropical ice core research:

http://www.pbs.org/wgbh/nova/sciencenow/video/0405/i04.html The following online article from the British Antarctic Survey address the history and field

logistics of ice coring: http://www.antarctica.ac.uk/indepth/icecore/page1.php The following is a video on the marine paleoclimate record and ocean drilling that students are

directed to in this exercise: http://recordings.wun.ac.uk/conf/nwo/oceandrilling2006

The following site contains coring statistics for the Deep Sea Drilling Project, the Ocean Drilling

Program, and the Integrated Ocean Drilling Program:

http://iodp.tamu.edu/publicinfo/ship_stats.html

A summary of the vessel specifications for the JOIDES Resolution can be found at:

http://www-odp.tamu.edu/publications/tnotes/tn31/jr/jr.htm (see reference for Garber,

2002). This website is a technical report that also includes descriptions and diagrams of the

different drilling and coring tools. Fact sheets on the science support technology and capabilities of the JOIDES Resolution and

the drill ship, the Chikyu, can be obtained at:

http://www.iodp.org/index.php?option=com_content&task=view&id=310&Itemid=975. Information on JOIDES Resolution coring tools can be found here:


Marine core photos can be obtained at: http://iodp.tamu.edu/database/coreimages.html Operational data of ODP Leg 199 can be accessed here:


To access a wide selection of short (~5 minute) videos on scientific ocean drilling go to:




http://www.youtube.com/watch?v=kdfcNIFEnF8

http://www.sciencemag.org/cgi/content/short/328/5982/1084

http://www.pbs.org/wgbh/nova/sciencenow/video/0405/i04.html

http://www.antarctica.ac.uk/indepth/icecore/page1.php

http://recordings.wun.ac.uk/conf/nwo/oceandrilling2006

http://iodp.tamu.edu/publicinfo/ship_stats.html

http://www-odp.tamu.edu/publications/tnotes/tn31/jr/jr.htm

http://www.iodp.org/index.php?option=com_content&task=view&id=310&Itemid=975


http://iodp.tamu.edu/database/coreimages.html



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http://joidesresolution.org/ and select resources video. The video “JR Drilling Operations 24/7” is a good one to learn more about the coring process on board the JOIDES Resolution. Another

good site that hosts short videos on scientific ocean drilling is the Ocean Leadership YouTube site: http://www.youtube.com/user/OceanLeadership.

V. References

Alley, R.B., et al., 1995, Comparison of deep ice cores. Nature, 373, 393–4.

Bender, M., et al., 1997, Gases in ice cores. Proceedings of the National Academy of Sciences, USA, 94, 8343–9.

Cronin, T., 1999. Principles of Paleoclimatology, Columbia University Press, 592 pp.

Graber, K.K., Pollard, E., Jonasson, B., and Schulte, E. (Eds.), 2002. Overview of Ocean Drilling Program engineering tools and hardware. ODP Tech. Note, 31. doi:10.2973/odp.tn.31.2002

[http://www-odp.tamu.edu/publications/tnotes/tn31/tn31.htm]

Li, Y.F., 1996, Global Population Distribution - 1990, Terrestrial Area, and Country Name Information

on a One-by-One Degree Grid-Cell Basis. Compiled by A.L. Brenkert, CDIAC, DB-1016, (1996), http://cdiac.ornl.gov/newsletr/spring97/datas97.htm

Lough, J.M. 2010, Climate records from corals. Wiley Interdisciplinary Reviews: Climate Change.1:

318–331. doi: 10.1002/wcc.39

Lowel, J.M., 2010, Climate records from corals. Climate Change, 1 (3), 318–31, doi:

10.1002/wcc.39, http://wires.wiley.com/WileyCDA/WiresArticle/wisId-WCC39.html

Marwan, N., Trauth, M.H., Vuille, M., et al., 2003. Comparing modern and Pleistocene ENSO-like influences in NW Argentina using nonlinear time series analysis methods. Climate Dynamics,

21:3–4, p. 317–326. doi:10.1007/s00382-003-0335-3.

Menking, K.M., 2000, A record of climate change from Owens Lake sediment, The Earth Around Us:

Maintaining a Livable Planet. Schneiderman, J.S. (ed.), W.H. Freeman and Company, New York, 322–35.

National Geophysical Data Center: http://www.ngdc.noaa.gov/mgg/curator/curator.html

NOAA Paleoclimatology database: http://www.ncdc.noaa.gov/paleo/

Piper, D.J.W. and Flood, R.D., 1997. Preface: Depth Below Seafloor Conventions. In Flood, R.D.,

Piper, D.J.W., Klaus, A., and Peterson, L.C. (Eds.), Proc. ODP, Sci. Results 155, 3–4,

http://www-odp.tamu.edu/publications/155_SR/CHAP_01.PDF.

Ruddiman, W.F., 2008, Earth’s Climate Past and Future, 2nd edition, Freeman, 388 pp.

Shipboard Scientific Party, 2002a. Explanatory notes. In Lyle, M., Wilson, P.A., Janecek, T.R., et al.,

Proc. ODP, Init. Repts., 199: College Station, TX (Ocean Drilling Program), 1–70.

doi:10.2973/odp.proc.ir.199.102.2002

Shipboard Scientific Party, 2002b. Site 1220. In Lyle, M., Wilson, P.A., Janecek, T.R., et al., Proc.

ODP, Init. Repts., 199: College Station, TX (Ocean Drilling Program), 1–93.

doi:10.2973/odp.proc.ir.199.113.2002

Stone, R., 2010, Arduous expedition to sample last virgin tropical glaciers. Science, 328 (May 28)

http://joidesresolution.org/

http://www.youtube.com/user/OceanLeadership

http://www-odp.tamu.edu/publications/tnotes/tn31/tn31.htm

http://cdiac.ornl.gov/newsletr/spring97/datas97.htm

http://wires.wiley.com/WileyCDA/WiresArticle/wisId-WCC39.html



http://www-odp.tamu.edu/publications/155_SR/CHAP_01.PDF


of 31

1084–5.

Whitman, J. 2005. What is a Core? A Deep Earth Academy Classroom resource: http://www.oceanleadership.org/classroom/cores.

Wilde, S.A., et al., 2001, Evidence from detrital zircons for the existence of continental crust and

oceans on the Earth 4.4 Gyr ago. Nature, 409, 175–8.

http://www.oceanleadership.org/classroom/cores

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