Presented by Julian D. Olden at the Madrean Conference (2012)

1. Streamflow variability of
dryland rivers in a
changing climate
Julian Olden1, Kristin Jaeger2 and
David Lytle3
1University of Washington, 2Ohio State University, 3Oregon State
University

2. Challenge Synopsis
• Rivers that intermittently cease to flow and “run dry” are
more representative of the world’s river systems than those
with perennial flows (Tooth 2000)
• The spatial and temporal
extent of temporary
rivers are likely to
further increase in
response to altered
land‐use, greater human
water use, and climate
change (Meehl et al. 2007,
Palmer et al. 2008) Datry et al. (2011)% Intermittent streams
0 10050
Nadeau & Rains (2007)

3. • Stream drying occurs at multiple
spatiotemporal scales (Stanley et al. 1997)
• Stream drying causes the loss of
longitudinal connectivity for
aquatic biota as well as for physical
processes throughout the river
network (Larned et al. 2010)
• Dry riverbeds serve a range of
important ecological values (Steward
et al. 2012)
When the river runs dry
Brown Canyon, Huachuca Mts, AZ
Aug 23, 2010
Aug 26, 2010

4. Spea multiplicata
(Mexican spadefoot)
Rana catesbeiana
(American bullfrog)
Hyla arenicolor
(canyon treefrog)
Anaxyrus punctatus
(red‐spotted toad)
Abedus herberti
(giant water bug)
Mesocapnia arizonensis
(stonefly)
Stictotarsus
aequinoctialis
(diving beetle)

5. 1. Explore present‐day
streamflow continuity
through time and
longitudinal connectivity
through space across a
riverine network
2. Forecast future changes
in continuity and
connectivity associated
with projected climate
change
Today’s presentation
N
Huachuca Mountain Range, AZ

6. • Standard methods for
monitoring stream and
groundwater conditions
typically occur at a small set
of geographic points at
frequent time intervals
• Field mapping approaches
can effectively quantify
longitudinal connectivity but
are limited by the frequency
of visits
Challenges to mapping flow permanence
Turner and Richter (2011)
1999 ….. 2010

7. Electrical Resistance Sensors
Sensor
modification
Exposed
wire
Exposed
wire
Adapted from Blasch
et al. (2002)
Stream drying Onset of continuous flow
Relative Conductivity
Time

8. • Spatial array of 44 ER
sensors to measure P/A
of streamflow
• Generating a near
continuous longitudinal
record of streamflow
timing from Apr 2010 –
present
• Quantify streamflow
continuity (continuous
through time) and
longitudinal
connectivity
(continuous in space)

9. t = 1 2 3 4 5 6 7
A
B
C
8
Connectivityover space
= 3/8 time periods or 37.5%
Continuity over time
= 6/8 time
periods or 75%
= 5/8 or 62.5%
= 4/8 or 50%

10. Streamflow Continuity and Connectivity
• Continuity of flow over time
varied from perennial (100%)
to intermittent (5‐70%) to
ephemeral (<5%)
• Average duration of a
monsoon “thunderstorm”
flow event:
– 5.2 h : intermittent
– 3.5 h : ephemeral
• The mountain front was
moderately connected
• Alluvial plain showed little
longitudinal connectivity
0.5%
0.2%
0.6%
0%
41%
22%
Jaeger and Olden (in press, River Research and Applications)

11. • More frequent and
earlier stream drying
in 2011 compared to
2010
– 30% decreased continuity
– 3.8 m earlier (9 d – 7 m)
• Earlier stream drying
correspond to either
the upper portions of
the headwaters or
the approximate base
of the mountain front
underlain by granitic
geology
2010 (average precipitation) vs. 2011 (dry)
Month
Oct Nov Dec Jan Feb Mar Apr May Jun
Difference in Precipitation, mm
‐20
0
20
40
60
80
100
120
Aerostat 2010
Aerostat 2011

12. Summary
• ER sensors facilitate a cost‐effective landscape approach to
quantify flow continuity and longitudinal connectivity
• Higher estimated longitudinal connectivity when possible
flow “refugia” are incorporated (Jaeger and Olden, in press)
• Streamflow is closely coupled to local precipitation and only
moderately corresponds to underlying geology
• Stream drying occurred substantially earlier and more
frequently following below‐average precipitation (2011)

13. 1. Quantify present‐day
streamflow continuity
through time and
longitudinal connectivity
through space across a
riverine network
2. Forecast future changes
in longitudinal
connectivity associated
with projected climate
change
Today’s presentation
N
Huachuca Mountain Range, AZ

14. http://www.tucson.ars.ag.gov
• Estimate flow magnitude, duration
and timing using the Soil Water
Assessment Tool (USDA)
• Distributed precipitation‐runoff
model with ArcGIS interface
• Change in # zero flow days
• Number of zero flow periods
• Duration of zero flow periods
Hydrologic Modeling
Framework
Model

15. Climate change predictions
0
2
4
6
8
10
12
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mean Daily Precipitation (mm)
2001‐2010 2082‐2091 Sierra Vista, AZ
Decrease
during onset
and peak
monsoon
period
Increase
during
early
winter
Damped intra‐annual
variability
* GFDL CM2.1 GCM, A2 greenhouse‐gas emissions scenario, spatially downscaled daily time‐step

16. Garden Canyon
River Km Station
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Garden Canyon: Mean Daily Discharge (2082 - 2091)
River Km Station
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
1e-04
0.001
0.01
0.1
0.5
1
cms
Downstream
Present Day (2001‐2010)
Future (2082‐2091)
no flow
Upstream
Mean
daily Q
Discharge
R=0.51 (P<0.01)
Permanence
R=0.42 (P<0.01)

17. Brown Canyon
River Km Station
1 2 3 4 5 6 7 8 9 10
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Brown Canyon: Mean Daily Discharge (2082 - 2091)
River Km Station
1 2 3 4 5 6 7 8 9 10
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Downstream Upstream
Present Day (2001‐2010)
Future (2082‐2091)
1e-04
0.001
0.01
0.1
0.5
cms
no flow
Mean
daily Q

18. ‐50
0
50
100
150
200
Overall Winter Spring Summer
Change (%)
Garden Brown Tinker McClure
‐50
‐25
0
25
50
75
100
Overall Winter Spring Summer
Change (%)
Garden Canyon
Brown Canyon
Tinker Canyon
McClure Canyon
Ü0 1 2 3 40.5
Kilometers
ByStation.ContinuityMetricDifferences
zfd_diff
Increase by 46 - 60 Days
Increase by 60 - 90 Days
Increase by 90 - 120 Days
Increase by 120 - 152 Days
Change in Zero Flow Days
Duration of Zero Flow Periods
Number of Zero Flow Periods

19. • Considerable spatial and temporal variability in flow
permanence is not captured by simple “perennial” or
“intermittent” stream types
• Network‐mapping of flow continuity and connectivity over
time can provide important insight into habitat permeability
and corridors for animal movement
• Climate‐induced stream drying and loss of flow connectivity
is highly probable
• Enhanced field monitoring coupled with hydrologic models
provide the opportunity to forecast the vulnerable of
temporary streams to increased water scarcity in the
Madrean Sky Islands
Conclusions

20. • Strategic Environmental
Research and
Development Program
(RC‐1724)
• Meryl Mims, Mike Bogan,
Britta Padgham, Noel
Pelland, Martin Schlaepfer
• Kyle Blasch, Brooke
Gebow, Bruce Gungle, Kyle
Molloy, Sheridan Stone
Acknowledgements