Trees as flood sensors

Maison des Sciences de l’Homme – Alpes | Université de Grenoble | June 27-30, 2016

TREES AS FLOOD SENSORS

Source: Greg Brooks, Geological Survey of Canada

THE RIGHT TREESIN THE RIGHT LOCATIONS

CAN PROVIDE RELIABLE AND PRECISE INSIGHTS

INTO THE OCCURRENCE AND MAGNITUDE OF PAST FLOODS.

TO TREES, RIVERS ARE HAZARDS

Source: Joe Zeleznik, North Dakota State University

IN WHAT MANNER DO RIPARIAN TREES PRESERVE EVIDENCE OF PALEOFLOODS?

3TILTING OR UPROOTING BY HYDRAULIC PRESSURE

2ANATOMICAL SIGNATURES WITHIN TREE RINGS

1SCARRING DUE TO IMPACT OR ABRASION

FUNDAMENTALS OF

DENDROCHRONOLOGY

12

EARLYWOOD

LATEWOOD

ONE GROWTH RING

CONIFER

HOW MANY (COMPLETE) TREE RINGS

ARE VISIBLE IN THIS MICROPHOTOGRAPH?

HOW MANY (COMPLETE) TREE RINGS

ARE VISIBLE IN THIS MICROPHOTOGRAPH?

Source: Daniel Griffin, University of Minnesota

1871 1872 1873 1874

Source: Daniel Griffin, University of Minnesota

NORTHWESTERN NEW MEXICO

Source: Daniel Griffin, University of Minnesota

CRATER LAKE NATIONAL PARK

Source: Sarah Appleton, University of Minnesota

1809 1811 181218081807

Source: Sarah Appleton, University of Minnesota

TREE-RING DATING IS NOT CONDUCTED BY SIMPLY COUNTING LAYERS (RINGS), BUT BY MATCHING PATTERNS ACROSS DOZENS OR HUNDREDS OF TREES.

TREE-RING DATING IS NOT CONDUCTED BY SIMPLY COUNTING LAYERS (RINGS), BUT BY MATCHING PATTERNS ACROSS DOZENS OR HUNDREDS OF TREES.

IN WHAT MANNER DO RIPARIAN TREES PRESERVE EVIDENCE OF PALEOFLOODS?

1SCARRING DUE TO IMPACT OR ABRASION

ROBERT SIGAFOOS (1920-1995) UNITED STATES GEOLOGICAL SURVEY

A SHARP BLOW TO A TREE TRUNK, WHETHER MADE BY A LAWN MOWER,

BY A BASEBALL BAT IN THE HANDS OF A SMALL BOY, OR BY DEBRIS CARRIED BY HIGH WATER,

WILL CRUSH, AND THUS KILL, THE LIVING TISSUES BENEATH THE BARK

AND THE WOOD.

“ ”Sigafoos, 1964

Botanical evidence of floods and flood-plain deposition

Source: Mark’s Postcards from Beloit

IMPACT OR ABRASION SCARS

Source: Juan Antonio Ballesteros-Cánovas , University of Bern

Source: Brian Luckman, University of Western Ontario

Source: NDSU Ag Comm

MISTASSINI RIVER, QUÉBEC

Source: Jeff Dumais

Source: Annie Lagadec

MISTASSINI RIVER, QUÉBEC

A SCAR-HEIGHT CHRONOLOGY WAS COMBINED WITH HYDRO-CLIMATIC DATA TO IDENTIFY CONDITIONS FAVORABLE TO TRIGGERING ICE JAMS.

Source: Lagadec et al., Hydrological Processes, 2015

HIGH-GRADIENT RIVERS

Source: Uday Kunwar Thapa, University of Minnesota

2ANATOMICAL SIGNATURES WITHIN TREE RINGS

QUERCUS

√

24

OAK TREE RINGS (NORMAL ANATOMY)

18

OAK TREE RINGS (ANATOMY DISRUPTED BY FLOODING)

11

THE RED RIVER OF THE NORTH

199715

Source: Greg Brooks, Geological Survey of Canada

42

SUBFOSSIL OAKS IN THE RED RIVER

Source: Erik Nielsen, Manitoba Geological Survey

QUERCUS MACROCARPA (MICHX.) GROWING ALONG THE RED RIVER, MANITOBA, CANADA,

CONTAIN AN ANATOMICAL SIGNATURE RELATED TO

HIGH-MAGNITUDE 19TH-CENTURY FLOODS.

“ ”St. George and Nielsen, 2000

Geology

FLOOD RINGS EXTENDED THE EVENT RECORD FOR THE RED RIVER OF THE NORTH BACK TO THE MID-1600S.

Source: St. George and Nielsen, The Holocene, 2003

PHENOLOGY

FLOODING CAUSES OAKS TO FORM NARROW EARLYWOOD VESSELS, BUT ONLY IF IT OCCURS AFTER BUDSWELL OR INTERNODE EXPANSION.

Source: Copini et al, , Frontiers in Plant Science, in press

Source: Wikipedia contributor Shannon1

MISSISSIPPI RIVER

BOTTOMLAND HARDWOODS, MISSISSIPPI

Source: Ma#hew Therrell, University of Alabama

3TILTING OR UPROOTING BY HYDRAULIC PRESSURE

Source: Juan Antonio Ballesteros-Cánovas , University of Bern

PALEODISCHARGE ESTIMATES

STRUCTURAL ENGINEERING

Source: Ballesteros et al., Journal of Hydrology, 2015

TILTED TREES GROWING IN FLOODPLAINS EXHIBIT REACTIONS CAUSED BY FLOOD, AND THEIR STRUCTURAL BEHAVIOR MAY BE LINKED TO FLOW CONDITIONS.

TAGUS RIVER, SPAIN

Source: Flickr user dailymatador

MECHANICAL MODELS ARE ABLE TO REPRODUCE THE OBSERVED TREE DEFORMATION, BUT ALSO CONSISTENTLY UNDERESTIMATE PEAK DISCHARGE.

Source: Ballesteros et al., Journal of Hydrology, 2015

10

THE GLOBAL TREE-RING NETWORK INCLUDES DATA FROM THOUSANDS OF LOCATIONS, BUT MOST (ALL?) OF THESE TREES ARE NOT AFFECTED BY FLOODING!

Source: St. George, Past Global Changes Magazine, 2014

THE RIGHT TREESIN THE RIGHT LOCATIONS

CAN PROVIDE RELIABLE AND PRECISE INSIGHTS

INTO THE OCCURRENCE AND MAGNITUDE OF PAST FLOODS.

Source: Ballesteros-Cánovas et al., Progress in Physical Geography, 2015

PALEOFLOOD STUDIES BASED ON TREE RINGS ARE STILL FEW, AND HAVE BEEN CONDUCTED ALMOST EXCLUSIVELY IN EUROPE, CANADA, AND THE UNITED STATES.

THE HISTORY OF PAST FLOODS, NOT THE HISTORICAL IDEALIZATION OF THEIR FUTURE POSSIBILITIES,

IS THE UNDERSTANDABLE BASIS UPON WHICH PEOPLE

MAY BE GUIDED TO EFFECTIVE ACTION.

“ ”Baker et al., 2002

The Scientific and Societal Value of Paleoflood Research

THE RED RIVER OF THE NORTH

1826

THE FORTS NOW STAND LIKE

A CASTLE OF ROMANCE IN THE MIDST OF

AN OCEAN OF DEEP CONTENDING CURRENTS,

THE WATER EXTENDING FOR AT LEAST A MILE BEHIND THEM…

“ ”

Francis Heron of the Hudson’s Bay Company May 1826

1826