class 1, introduction to dendrochronology

I N T R O D U C T I O N T O D E N D R O C H R O N O L O G Y

2010 Dec-Nov temperature anomaly h"p://www.giss.nasa.gov/

NASA global temperature record h"p://www.giss.nasa.gov/

QUESTIONIs it unusual for the world to be this warm?

Water transfers in the American southwest

Courtesy Glen MacDonald

Low reservoir

Photograph: Glen MacDonald

QUESTIONIs there enough water in the Colorado River

to satisfy the expected need?

Photograph: watsonsinelgin

Photograph: Howard Arno!

QUESTIONWhen were these dwellings

constructed (and abandoned)and why?

Photograph: Tom Swetnam

Photograph: WhineAndDine

QUESTIONHow does weather and climate affect the

risk and severity of forest fires?

Photograph: Greg Brooks

Red RiverManitoba

AP Photo/U.S. Coast Guard, Lt. Brendan Evans

QUESTIONHow often does the Red River

produce extreme floods?

Tree at Chancellorsville

Photograph: Andy Frasse!o

Tree-ring display at elementary school

Photograph: Tom Swetnam

A. E. Douglass University of Arizona

The trees composing the forest rejoice and lament with its successes and failures and carry year by year something of its story in their annual rings.”

“

Same environmental conditions

Similar growth pa"erns

25

1900 1910 1920 1930

Two Douglas-fir cores from Eldorado Canyon, CO

Graphic: Jeff Lukas, INSTAAR

THE PRINCIPLE OF CROSS-DATING

Photo: Howard ArnottFrost damage Photograph: Howard Arno!

Fire scars

The science of dendrochronology uses information encoded into the annual growth rings of trees to address issues related to climate change, hazards, ecology and natural history.

Photo: Chris MullinsGiant sequoia 3,266 years Photograph: Chris Mullins

Bristlecone pine 4,844 years Photograph: Tom Harlan

White pine 1714

Photo: Kurt Kipfmueller

Photo: Danny Margoles

White cedar 1452

I N T R O D U C T I O N T O D E N D R O C H R O N O L O G Y

Fundamentals Tree-ring anatomy Photograph: Kevin Anchukaitis

Fundamentals Weather, climate and tree growth Photograph: dr_tim_1956

Fundamentals History of dendrochronology

Fundamentals Statistical tools for tree-ring analysis

Applications Drought risks Photograph: Library of Congress

Applications Fire ecology Photograph: Don Falk

Applications Natural hazards and landscape processes Photograph: Erica Bigio

Applications Forest ecology Photograph: Whitney Crawford

43Applications Maritime archeology

I N T R O D U C T I O N T O D E N D R O C H R O N O L O G Y

Who am I?

Tree-ring display at elementary school

Photograph: Tom Swetnam

Photograph: Dave Sauchyn

Photo: Calvin Ferris Kurt Kipfmueller University of Minnesota

umndendro.umn.edu

GEOG3839 Nuts and boltsGEOG5839

Links to course syllabus, scheduleat h!p://umn.edu/~stgeorge under ‘Teaching’

GEOG3839

Mid-term

Exercises (4)

Final exam

30%

40%

30% GEOG5839

Mid-term

Exercises (4)

Project

20%

40%

40%

G R A D I N G W E I G H T S

Trees are among the oldest living things on our planet. Many trees can live for several centuries and a few exceptional specimens have survived for more than 5,000 years. In part because of their great age, the annual growth rings from trees provide us with an incredibly powerful and adaptable tool to study Earth’s history. The rings tell us much more than just a tree’s age. They also provide clues that help us understand how our environment has changed in the past, and provide insights into how key processes in atmosphere, biosphere and geological systems operate over long timescales.

The science of dendrochronology uses information encoded into the annual growth rings of trees to address issues related to climate change, hazards, ecology and natural history. Because tree vitality is strongly influenced by local environmental conditions, major events such as a change in climate, insect a!ack or severe flood o"en create a distinct ‘fingerprint’ in the tree’s rings. By studying these signatures in the rings, we can develop an annual record of past environmental events extending back several centuries or millennia.

Links to course syllabus, scheduleat h!p://umn.edu/~stgeorge under ‘Teaching’

Readings!Smith and Lewis (2006), Dendrochronology

What can you expect to learn?

DENDROCHRONOLOGY is much more than just counting tree rings