coming full circle introspective thinking for a retrospective science henri d. grissino-mayer...

COMING FULL CIRCLEINTROSPECTIVE THINKING FOR A RETROSPECTIVE

SCIENCE

COMING FULL CIRCLEINTROSPECTIVE THINKING FOR A RETROSPECTIVE

SCIENCE

Henri D. Grissino-Mayer

Department of GeographyThe University of

TennesseeKnoxville, Tennessee

37996

Henri D. Grissino-Mayer

Department of GeographyThe University of

TennesseeKnoxville, Tennessee

37996

* With contributions from Tom Swetnam, Jim Speer, Peter Brown, Paolo Cherubini, Paul Sheppard,

and many, many other dendrochronologists over the years.

* With contributions from Tom Swetnam, Jim Speer, Peter Brown, Paolo Cherubini, Paul Sheppard,

and many, many other dendrochronologists over the years.

**

PublicationsPublications

“Publications are the currency of science. If our work is not published, then it may as well not be done at all. In addition to communicating our science broadly, publications enhance our ability to continue our work by building a foundation of knowledge and understanding, and by conferring credibility that is essential to obtain the necessary research funding in an increasingly competitive field.”

“Publications are the currency of science. If our work is not published, then it may as well not be done at all. In addition to communicating our science broadly, publications enhance our ability to continue our work by building a foundation of knowledge and understanding, and by conferring credibility that is essential to obtain the necessary research funding in an increasingly competitive field.”– Thomas W. Swetnam, memo dated 18 August 1995,

sent to his students, staff, and post-docs– Thomas W. Swetnam, memo dated 18 August 1995,

sent to his students, staff, and post-docs

BibliometricsBibliometrics

Quantitative analyses that describe patterns of publication within a given field (Palmquist 2008)Quantitative analyses that describe patterns of publication within a given field (Palmquist 2008)

Used to evaluate the influence of single researchers, such asthe h-index, which quantifies both the actual scientific productivity and the apparent scientific impact for a researcher.

Used to evaluate the influence of single researchers, such asthe h-index, which quantifies both the actual scientific productivity and the apparent scientific impact for a researcher. Lotka's Law of Scientific Productivity: (1) number of

authors making n contributions is about 1/n2 of those making one contribution; and (2) the proportion of all researchers thatmake one contribution is about 60% (but this has changed).

Lotka's Law of Scientific Productivity: (1) number of authors making n contributions is about 1/n2 of those making one contribution; and (2) the proportion of all researchers thatmake one contribution is about 60% (but this has changed).

Has been a mainstay in documentation science since the1920s (Broadus 1987)

Has been a mainstay in documentation science since the1920s (Broadus 1987)

Bibliometrics is also used to evaluate the influence of journals via citation analysesBibliometrics is also used to evaluate the influence of journals via citation analyses

Science Citation Index, Social Science Citation Index, and Impact Factor RatingScience Citation Index, Social Science Citation Index, and Impact Factor Rating


Lotka's Law of Scientific Productivity:

Based on the total number of publications in Dendrochronology (11,300), and assuming 1/3rd are one-time publications, we should have approximately 12 scientists with 72 or more publications:

Dendrochronologist 1 : 201Dendrochronologist 2 : 158Dendrochronologist 3 : 127*Dendrochronologist 4 : 111Dendrochronologist 5 : 111* Dendrochronologist 6 : 106Dendrochronologist 7 : 101*Dendrochronologist 8 : 95Dendrochronologist 9 : 87Dendrochronologist 10: 85Dendrochronologist 11: 84Dendrochronologist 12: 75Dendrochronologist 13: 74




7 European6 American



WHAT IS BEING STUDIED IN DENDROCHRONOLOGY,AND WHEN WAS IT BEING STUDIED?

WHAT IS BEING STUDIED IN DENDROCHRONOLOGY,AND WHEN WAS IT BEING STUDIED?


Spatiotemporal Trends in Dendrochronology:

Major Categories: Climate, Archaeology, Ecology, Geomorphology, Hydrology, Isotopes, and Physiology

Temporal Trends in Dendrochronological Publications

Spatial Trends in Dendrochronological Publications

Trends Assessed for the Last 20 Years (1987–2006)

Caveats:Inclusion in the bibliographic database assumes that

tree rings were treated in some substantial way.Some publications are listed in more than one category

(e.g. isotopes and climate), especially review articles.

Some publications may be missing (which emphasizes the importance of sending publications to me).

Geographical analyses are based on where the research is being conducted, not by whom.

However, most researchers conduct their studies in their native country (but note exceptions, e.g. LDEO).

Spatiotemporal Trends in Dendrochronology:

Major Categories: Climate, Archaeology, Ecology, Geomorphology, Hydrology, Isotopes, and Physiology

Temporal Trends in Dendrochronological Publications

Spatial Trends in Dendrochronological Publications

Trends Assessed for the Last 20 Years (1987–2006)

Caveats:Inclusion in the bibliographic database assumes that

tree rings were treated in some substantial way.Some publications are listed in more than one category

(e.g. isotopes and climate), especially review articles.

Some publications may be missing (which emphasizes the importance of sending publications to me).

Geographical analyses are based on where the research is being conducted, not by whom.

However, most researchers conduct their studies in their native country (but note exceptions, e.g. LDEO).

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EcologicalApplications

EcologicalApplications

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Fire Studies

Fire Studies

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Insect Studies

Insect Studies

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Forest Health

Forest Health

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ClimaticApplications

ClimaticApplications

Temp ReconPrecip Recon

Temp ReconPrecip Recon

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ArchaeologicalApplications

ArchaeologicalApplications

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IndicatesEnglish Heritage


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Applications inGeomorphology

Applications inGeomorphology

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IsotopeStudies

IsotopeStudies

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Studies inHydrology

Studies inHydrology

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Studies inPhysiology

Studies inPhysiology

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All Publications in Dendrochronology

All Publications in Dendrochronology



OverallTrend

OverallTrend


Years withProceedings Volumes

Years withProceedings Volumes


WHERE IS DENDROCHRONOLOGY BEING CONDUCTED?WHERE IS DENDROCHRONOLOGY BEING CONDUCTED?

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Studies Conducted in U.S.


Studies Conducted in Europe


0%

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60%

70%

80%

90%

100%

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010





The “Hollstein-Corona Effect”

The “Hollstein-Corona Effect”

The “Schweingruber-Eckstein Effect”

The “Schweingruber-Eckstein Effect”

NE U.S.NE U.S. NE U.S.NE U.S.

SE U.S.SE U.S. SE U.S.SE U.S.

MidwestMidwestMidwestMidwestNorth-North-CentralCentral

North-North-CentralCentral

South-South-CentralCentral

South-South-CentralCentral

NW U.S.NW U.S. NW U.S.NW U.S.

SW U.S.SW U.S. SW U.S.SW U.S.

NW U.S.NW U.S. NW U.S.NW U.S.

292292

348348

131131

110110

164164

509509

10081008

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60

70

80

90

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010


Eastern U.S.Central U.S.

Western U.S.

Eastern U.S.Central U.S.

Western U.S.

Numbers begin increasing ca. 1979

Numbers begin increasing ca. 1979

15 Top European countries15 Top European countrieswhere Dendrochronologywhere Dendrochronologyis most conductedis most conducted

United KingdomUnited Kingdom

GermanyGermany

SwitzerlandSwitzerland

FranceFrance

ItalyItaly

SwedenSweden FinlandFinlandNorwayNorway

PolandPoland

AustriaAustria

SpainSpain

IrelandIreland

NetherlandsNetherlands

SloveniaSlovenia

Czech RepublicCzech Republic

911911

637637

503503

412412

325325

204204200200

148148

140140

101101

7979

7777

6262

5959

5353

15 Top European countries15 Top European countrieswhere Dendrochronologywhere Dendrochronologyis most conductedis most conducted

403403

0%

20%

40%

60%

80%

100%

1970 1980 1990 2000


GermanyGermany

United KingdomUnited Kingdom

SwitzerlandSwitzerland

FranceFrance

157157

116116

2121

48488585

254254

2727

1616

2626

4949

YukonYukon

Northwest TerritoriesNorthwest Territories

British ColumbiaBritish Columbia

AlbertaAlberta

SaskatchewanSaskatchewan

ManitobaManitoba

OntarioOntario

QuébecQuébecNewfoundland/

LabradorNewfoundland/

Labrador

Nova Scotia, New Brunswick, Prince Edward

Island

Nova Scotia, New Brunswick, Prince Edward

Island

3232

7575 124124

Other South and Central American Countries:

Costa Rica: 12 Peru: 9Bolivia: 9 Venezuela: 6Fr. Guyana: 3 Panama: 3Uruguay: 2

MexicoMexico

BrazilBrazil

ArgentinaArgentinaChileChile

9797

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Studies Conducted in Canada

Studies Conducted in Canada

Studies Conducted in South America

Studies Conducted in South America

OverallTrend

OverallTrend

OverallTrend

OverallTrend

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30

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Studies Conducted in Russia

Studies Conducted in Russia

Studies Conducted in Australasia

Studies Conducted in Australasia

OverallTrend

OverallTrend

OverallTrend

OverallTrend


WHERE IS DENDROCHRONOLOGY BEING PUBLISHED?WHERE IS DENDROCHRONOLOGY BEING PUBLISHED?


Impact Factor (IF):Developed in 1960s by Institute for Scientific Information (ISI), now Thomson Scientific, and used in-house for Science Citation Index and Social Science Citation Index.

In 1975, Thomson Scientific began publishing Journal Citation Reports.

Simple ratio: IF(t) = -----------------------------------------------------------------

Only relevant when considering the rank of the journal in a category of its peers (note: IF of 2.0 is considered good for natural/physical sciences).

Faults include self-citations, review articles, exclusion of books/book chapters, short 2-yr window, editorial manipulation, time lag of issue release, skewed by one or a few articles

Reality: despite its faults, IF is increasingly used to measure productivity of researchers, affecting both hiring and promotion.

IF will affect outlets chosen by researchers for publication, especially proceedings volumes and books.

Impact Factor (IF):Developed in 1960s by Institute for Scientific Information (ISI), now Thomson Scientific, and used in-house for Science Citation Index and Social Science Citation Index.

In 1975, Thomson Scientific began publishing Journal Citation Reports.

Simple ratio: IF(t) = -----------------------------------------------------------------

Only relevant when considering the rank of the journal in a category of its peers (note: IF of 2.0 is considered good for natural/physical sciences).

Faults include self-citations, review articles, exclusion of books/book chapters, short 2-yr window, editorial manipulation, time lag of issue release, skewed by one or a few articles

Reality: despite its faults, IF is increasingly used to measure productivity of researchers, affecting both hiring and promotion.

IF will affect outlets chosen by researchers for publication, especially proceedings volumes and books.

Total citations in yr (t) to articles in yrs (t-1) and (t-2)Total citations in yr (t) to articles in yrs (t-1) and (t-2)Total journal articles published in yrs (t-1) and (t-2)Total journal articles published in yrs (t-1) and (t-2)


1999 Rank

2000 Rank

2001 Rank

2002 Rank

2003 Rank

2004 Rank

2005 Rank

2006 Rank

AGR FOREST METEOROL 3 4 2 2 1 1 1 1

J VEG SCI 2 3 3 3 3 3 2 2

TREE PHYSIOL 1 1 1 1 2 2 3 3

FOREST ECOL MANAG 9 6 11 5 6 5 5 4

INT J WILDLAND FIRE -- 23 17 20 5 11 4 5

CAN J FOREST RES 6 9 7 6 4 7 6 6

TREES-STRUCT FUNCT 5 5 4 4 7 9 9 7

FOREST SCI 7 8 8 8 11 12 8 8

PLANT ECOL 4 11 9 7 8 10 16 9

ANN FOREST SCI -- 15 5 9 10 8 10 10

APPL VEG SCI -- -- -- -- 12 4 7 11

J FOREST 11 19 22 25 13 20 15 12

HOLZFORSCHUNG 8 7 10 11 14 13 11 13

AGROFOREST SYST -- 10 6 13 20 18 23 14

FOREST POLICY ECON -- -- -- -- 29 32 14 15

SILVA FENN -- -- 16 18 17 6 24 16Source: Journal Citation Reports


1999 Rank

2000 Rank

2001 Rank

2002 Rank

2003 Rank

2004 Rank

2005 Rank

2006 Rank

SCAND J FOREST RES 17 16 15 10 16 14 18 17

FORESTRY -- 13 18 21 22 23 13 18

FOREST CHRON 13 21 24 19 23 27 21 19

NORTH J APPL FOR -- -- -- -- -- 30 29 20

EUR J FOREST RES -- -- -- -- -- 34 25 21

WOOD SCI TECHNOL -- 26 21 17 19 15 26 22

FOREST PATHOL -- 29 28 24 9 21 20 23

SOUTH J APPL FOR -- -- -- -- -- 28 33 24

NEW FOREST 20 21 19 22 24 19 28 25

IAWA J 12 12 12 12 18 17 27 26

NAT AREA J 10 18 13 14 15 16 19 27

TREE-RING RES -- -- -- -- -- -- 12 28

INT FOREST REV -- -- -- -- -- 31 17 29

WOOD FIBER SCI 18 20 20 16 21 22 31 30

WEST J APPL FOR -- -- -- -- -- 26 30 31

FOREST PROD J -- 24 26 23 25 25 32 32

ALLG FORST JAGDZTG -- 28 27 27 27 33 35 33

SILVAE GENET 19 25 25 26 28 29 34 34Source: Journal Citation Reports

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400


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Where have we been publishing?


93 94 100 102 114 116 121 125

193

247

331343

372

3051 publications in just 25 journals, representing 27% of

all publications since 1920

3051 publications in just 25 journals, representing 27% of


807066656459585149474645

1046 publications in just 3 journals, representing 9.2% of


1046 publications in just 3 journals, representing 9.2% of





3051 publications in just 25 journals, representing 27%

of all publications!

3051 publications in just 25 journals, representing 27%

of all publications!

0

1

2

3

4

5

6

7

8

9

10

Jour

nal o

f Eco

logy

Canad

ian Jo

urna

l of B

otan

y

Leso

vede

nie

Climat

ic Cha

nge

Jour

nal o

f Biog

eogr

aphy

Fores

t Scie

nce

Schweiz

erisc

he Z

eitsc

hrift

für F

orstw

esen

Trees

- Stru

cture

and

Fun

ction

Scienc

e

Geoph

ysica

l Res

earc

h Le

tters

Jour

nal o

f For

estry

Quate

rnar

y Res

earc

h

The H

oloce

ne

Annals

of F

ores

t Scie

nce

IAW

A Jour

nal

Verna

cular

Arc

hitec

ture

Ecolog

y

Fores

t Eco

logy a

nd M

anag

emen

t

Natur

e

Arctic

, Ant

arcti

c, an

d Alpi

ne R

esea

rch

Radioc

arbo

n

Englis

h Her

itage

Canad

ian Jo

urna

l of F

ores

t Res

earc

h

Dendr

ochr

onolo

gia

Tree-

Ring R

esea

rch

ImpactFactor

ImpactFactor

30.02830.028 26.68126.681

0.6250.6251.5491.549

2.5382.538

0.9310.931

1.8391.839

4.7824.782

0.6670.667

1.2901.290

2.0002.0002.3192.319

1.1881.188

2.6022.602

1.4611.4611.4571.457

2.8782.8782.4592.459

1.1931.193

4.2394.239

Other High-Impact Journals

Ecological Applications (26): 3.470Journal of Climate (30): 3.419Journal of Vegetation Science (32): 2.382Tree Physiology (34): 2.297Ecoscience (36): 1.174

Other High-Impact Journals

Ecological Applications (26): 3.470Journal of Climate (30): 3.419Journal of Vegetation Science (32): 2.382Tree Physiology (34): 2.297Ecoscience (36): 1.174


0

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10

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30

35

40

45

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Publications in Top 10 Journals

Publications in Top 10 Journals

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25

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

% Publications in Top 10 Journals

% Publications in Top 10 Journals


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1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Better Journals in Last 20 Years

Better Journals in Last 20 Years

0

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25

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Maintaining at the 10% Level

Maintaining at the 10% Level

Studies Conducted in Rest of Asia


0

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30

35

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

Graduate Degrees in the Tree-Ring Sciences

Graduate Degrees in the Tree-Ring Sciences

Studies Conducted in Africa


0

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4

6

8

10

12

14

1920 1930 1940 1950 1960 1970 1980 1990 2000 2010

% Graduate Degrees in the Tree-Ring Sciences

% Graduate Degrees in the Tree-Ring Sciences

Lowest Productivity (%) since 1970

Lowest Productivity (%) since 1970

Doctoral Masters

Doctoral Masters

ConclusionsConclusions

Signs of a healthy discipline:Signs of a healthy discipline:

Increasing importance of timely economic and societal issues that can be addressed with tree-ring data (e.g., water resources and fire history studies).

Increasing importance of timely economic and societal issues that can be addressed with tree-ring data (e.g., water resources and fire history studies).

Increasing importance of issues that have global significance and can be addressed with tree-ring data (e.g., climate change).

Increasing importance of issues that have global significance and can be addressed with tree-ring data (e.g., climate change).

Increasing exposure in the media: news channels, documentaries, Congressional hearings, popular books and text books.

Increasing exposure in the media: news channels, documentaries, Congressional hearings, popular books and text books.Greater visibility by the dendrochronological organizations: TRS, ATR, and CanDendro.Greater visibility by the dendrochronological organizations: TRS, ATR, and CanDendro.

Increasing numbers of dendrochronologists that are members on the ITRDBFOR Internet forum (up to 670 members).

Increasing numbers of dendrochronologists that are members on the ITRDBFOR Internet forum (up to 670 members).

Increasing publications in higher quality journals.Increasing publications in higher quality journals.


Signs of a healthy discipline:Signs of a healthy discipline:

Increasing number of educational venues: NADEF, International Dendroecological Fieldweek, Asian fieldweek, Tucson summer courses, wood anatomy workshops

Increasing number of educational venues: NADEF, International Dendroecological Fieldweek, Asian fieldweek, Tucson summer courses, wood anatomy workshops

Increasing numbers of dendrochronologists holding positions as professors and starting their own labs, i.e., our graduate students are finding employment!

Increasing numbers of dendrochronologists holding positions as professors and starting their own labs, i.e., our graduate students are finding employment!

Increasing presence of dendrochronologists at national and international meetings: AAG, CAG, AGU, GSA, ESA, Forestry, Landscape Ecology, Wood Anatomy.

Increasing presence of dendrochronologists at national and international meetings: AAG, CAG, AGU, GSA, ESA, Forestry, Landscape Ecology, Wood Anatomy.

Increasing number of dendrochronology-specific national and international meetings where we can congregate and exchange ideas: TRACE, AmeriDendro, ICD, EuroDendro

Increasing number of dendrochronology-specific national and international meetings where we can congregate and exchange ideas: TRACE, AmeriDendro, ICD, EuroDendro

Impressive production of graduate students in the tree-ring sciences in recent decades.Impressive production of graduate students in the tree-ring sciences in recent decades.


Decreasing importance of certain key focal areas once held in high regard by the scientific community (e.g., archaeology and forest health).

Decreasing importance of certain key focal areas once held in high regard by the scientific community (e.g., archaeology and forest health).

Shift away from publishing proceedings volumes, which previously had greatly boosted visibility.Shift away from publishing proceedings volumes, which previously had greatly boosted visibility.

We’re healthy, but have a cold!We’re healthy, but have a cold!

No doubt, the retirements of several prominent names in dendrochronology have affected and will continue to affect productivity in the field.

No doubt, the retirements of several prominent names in dendrochronology have affected and will continue to affect productivity in the field.

“Graying” of the field as professors become tenured and productivity decreases as responsibilities change.“Graying” of the field as professors become tenured and productivity decreases as responsibilities change.

Some signs of slow-down in attracting high-quality graduate students into the field (lowest 3 year % recently since ca. 1970).

Some signs of slow-down in attracting high-quality graduate students into the field (lowest 3 year % recently since ca. 1970).

COMING FULL CIRCLE:INTROSPECTIVE THINKING FOR A RETROSPECTIVE

SCIENCE

COMING FULL CIRCLE:INTROSPECTIVE THINKING FOR A RETROSPECTIVE

SCIENCE

THANK YOU!THANK YOU!




: 201: 158: 127*: 111: 111* : 106: 101*: 95: 87: 85: 84: 75: 74



: 201: 158: 127*: 111: 111* : 106: 101*: 95: 87: 85: 84: 75: 74

Name Pubs Range Yrs Pubs/Yr h-index1. Fritz H. Schweingruber 1964–2007 44 4.6 192. Dieter Eckstein 1967–2006 40 4.0 93. Edward R. Cook 1976–2008 33 3.8 414. Michael G.L. Baillie 1972–2006 35 3.2 175. Gordon C. Jacoby 1976–2008 33 3.4 206. Harold C. Fritts 1956–2005 50 2.1 147. Rosanne D’Arrigo 1987–2008 22 4.6 198. Ernst Hollstein 1964–1988 25 3.8 39. Keith R. Briffa 1983–2007 25 3.5 1810.Elio Corona 1958–2004 47 1.8 011.Bernd Becker 1968–1999 32 2.6 2012.Andrew E. Douglass 1909–1949 41 1.8 1513.Thomas W. Swetnam 1982–2007 25 3.0 20

Name Pubs Range Yrs Pubs/Yr h-index1. Fritz H. Schweingruber 1964–2007 44 4.6 192. Dieter Eckstein 1967–2006 40 4.0 93. Edward R. Cook 1976–2008 33 3.8 414. Michael G.L. Baillie 1972–2006 35 3.2 175. Gordon C. Jacoby 1976–2008 33 3.4 206. Harold C. Fritts 1956–2005 50 2.1 147. Rosanne D’Arrigo 1987–2008 22 4.6 198. Ernst Hollstein 1964–1988 25 3.8 39. Keith R. Briffa 1983–2007 25 3.5 1810.Elio Corona 1958–2004 47 1.8 011.Bernd Becker 1968–1999 32 2.6 2012.Andrew E. Douglass 1909–1949 41 1.8 1513.Thomas W. Swetnam 1982–2007 25 3.0 20

02468

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Colora

do S

tate

North

ern

Arizon

a

Penn

State

Queen

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Lava

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UCLA

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Colu

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Victor

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Wes

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Arizon

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Graduate Degrees in the Tree-Ring Sciences, 1998–2007

Graduate Degrees in the Tree-Ring Sciences, 1998–2007


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Europe U.S.

Canada

Europe U.S.

Canada

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coming full circle introspective thinking for a retrospective science henri d. grissino-mayer...

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