Climate Change Effects on Water

John Campbell Research Ecologist

USDA Forest Service, Durham, NH

Climate Change & New England Forests Hubbard Brook Experimental Forest

November 18-19, 2015

Long-term climate indicators at HB

Meteorological • Air temperature • Solar radiation • Relative humidity • Wind speed

Soil • Soil temperature • Soil moisture • Soil Frost • Sediment

Biological • Phenology • Birds • Vegetation composition • Litterfall • Tree cores Hydrological

• Lake ice in/out • Streamflow • Precipitation • Stream temperature • Snow depth/SWE • Lake thermal profiles • Water isotopes

Climate change = hydrologic change

Google Ngram viewer

Michel et al. 2011. Science.

Observed US precipitation change

Annual total precipitation change for 1991-2012 compared to the 1901-1960 average.

Melillo et al. 2014. National Climate Assessment.

Hubbard Brook precipitation

Water Year (Jun 1)1950 1960 1970 1980 1990 2000 2010

Prec

ipita

tion

(inch

es)

30

35

40

45

50

55

60

65

70

75

80

Rain gage 1Rain gage 2Rain gage 3

Regional trends in precipitation

Water Year (Jun 1)1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020

Prec

ipita

tion

(inch

es)

25

30

35

40

45

50

55

60

65

70

75

Hubbard BrookRegional average

Regional trends in precipitation

Water Year (Jun 1)1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 2010 2020

Prec

ipita

tion

(inch

es)

25

30

35

40

45

50

55

60

65

70

75

Hubbard BrookRegional average

6.7 inches (p=0.011)

11.7 inches (p=0.002)

Why is precipitation increasing?

• Warmer air can hold more water vapor

• Storm tracks are changing

Stephens. 2011. Nature Climate Change

Soil moisture

Groffman et al. 2012 BioScience

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000

Avg

. soi

l moi

stur

e (in

.)

0.00

0.25

0.50

0.75

1.00

1.25

1.50

1.75

2.001 in. depth3 in. depth12 in. depth

Max

. sno

w d

epth

(in)

0

10

20

30

40

50

60

1955 1965 1975 1985 1995 2005 2015

Snow

cov

er (d

ays)

40

60

80

100

120

140

160

180

Updated from Campbell et al. 2007 – FS Gen. Tech. Rep.

Snowpack

-10 inches

-21 days

The “Spring Trigger”

Groffman et al. 2012. BioScience

Soil frost depth

Winter

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015

Max

. soi

l fro

st d

epth

(in)

-12

-10

-8

-6

-4

-2

0

Station 2Station 17

Future changes in soil frost

1979-2008 mean

GFDL (Hi CO2) Δ/2009-99

GFDL (Low CO2) Δ/2009-99

HADLEY (Hi CO2) Δ/2009-99

HADLEY (Low CO2) Δ/2009-99

PCM (Hi CO2 ) Δ/2009-99

PCM (Low CO2) Δ/2009-99

Max. frost depth (inches)

3.9 0 -2.0 -0.4

+0.4

+0.4

-1.2

Frost duration (days)

98 -32 -21 -54 -8 -24 -24

Freeze-thaw events (count)

4 +3 +2 +2 0 +1 0

Campbell et al. 2010. Hydrological Processes

P<0.05

Changes in streamflow

Campbell et al. 2011. Water Resources Research

Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct

Dai

ly s

tream

flow

(in)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

1969present

Watershed 8

Top 20 streamflow events

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan

Stre

am d

isch

arge

(ft3

/sec

)

0

10

20

30

40

50

60

70

Rain-on-snow

Snowmelt

Convective rainfall

Frontal rainfall Hurricanes

• August 28, 2011 • 7th costliest hurricane • Up to 10 inches of rain in NH

Tropical Storm Irene

Photographs courtesy of S. Bailey

Aug. 29 2011

High flow days are increasing

High flow days are increasing also

Number of days per year with streamflow > 95th percentile

Day

s

05

10152025303540

W6

Water Year (Jun 1)

1955 1965 1975 1985 1995 2005 2015

Day

s

05

10152025303540

W3

0.154 days/yrP=0.014

0.176 days/yrP=0.003

95th pctl. = 0.026 mm

95th pctl. = 0.028 mm

Number of days per year with streamflow < 5th percentile

Day

s

0102030405060708090

100W6

Water Year (Jun 1)

1955 1965 1975 1985 1995 2005 2015

Day

s

0102030405060708090

100W3

-0.333 days/yrP=0.018

-0.511 days/yrP=0.000

Low flow days are decreasing

Regional Trends in Flood Frequency

Collins. 2009. Journal of the American Water Resources Association

Photograph courtesy of Scott Bailey, USFS

• Sediment can adversely affect stream biota

• Sediment can also

affect stream morphology

• High flow events produce the most sediment

Water quality impacts (erosion/sedimentation)

• Evidence that stream water temperatures are rising nationally

• Influences abundance and distribution of freshwater plants and animals

Photograph courtesy of US Fish and Wildlife Service

Eastern brook trout

• Alters chemistry (e.g., dissolved oxygen)

• Made worse by deforestation, industrial discharge, impervious surfaces, impoundments

Water quality impacts (water temperature)

Water quality impacts (nutrients)

Campbell et al. 2009. Canadian Journal of Forest Research

What do these changes in climate mean

for land managers?

Impacts on harvesting

Photograph by Jerry Monkman

• Less snow might be good

• Shorter period of frozen soil is bad

• Especially bad for harvesting species that grow on moist, poorly drained soils.

Can forest management mitigate/exacerbate

climate change effects on water?

Impacts on infrastructure

Photograph courtesy of Brian Austin, USFS, Green Mountain National Forest

• Damage to roads, bridges, culverts, and dams

• Data from the past is

not reliable for making predictions for the future

• Design with climate

change in mind

Impacts on recreational activities

Roundtable discussion on snowmobiling

• How will recreational activities be impacted?

• How will we adapt?

Thank you!

Photograph by Gordon Chibroski