Climate Change and
Potential Hydrologic
Consequences in
British Columbia
R.D. (Dan) Moore PhD PGeo
Department of Geography and
Department of Forest Resources
Management
The University of British Columbia
T. Gallie
Acknowledgements
Government of Canada – Climate Change
Impacts and Adaptations Research Network
Environment Canada – Pacific and Yukon Region
Canadian Foundation for Climate and
Atmospheric Science
The University of British Columbia – Office
of the VP Research
Outline
  Climate change and hydrology – direct and indirect
effects
  Streamflow regimes in British Columbia
  Climate change scenarios
  Effects of climate change on streamflow in BC
  Key points
Climate change and hydrology – direct and
indirect influences
Direct effects
  Changes in precipitation
  Changes in air temperature
Indirect effects
  Changes in glacier extents
  Changes in vegetation patterns
Streamflow regimes in British Columbia
  Rain-dominated (pluvial)
  Snowmelt-dominated (nival)
  Glacier fed (pro-glacial)
  Hybrid (pluvio-nival)
Rain-dominated
Hybrid
Capilano River
Snow-dominated
Coquihalla River
Glacier-fed
Future climate scenarios
Scenarios are …
Plausible future climates that have been constructed
for determining the impacts of climate change on
environmental and resource systems of importance
to human society
Future climate scenarios
Scenarios are …
Plausible future climates that have been constructed
for determining the impacts of climate change on
environmental and resource systems of importance
to human society
Scenario vs prediction
Scenarios acknowledge uncertainties in future
regulations, changes in societal values: “Scenarios”
embrace uncertainty
“Predictions” suggest a higher level of certainty
Special Report on Emission Scenarios (SRES)
  Commissioned for IPCC Third Assessment
Report
  Four main “story lines”
− A1 (A1F1, A1B, A1T)
− A2
− B1
− B2
Scenarios – examples
  SRES A2
(Divided world)
−  A world of independently
operating, self-reliant nations
−  Continuously increasing
population
−  Slower and more fragmented
technological changes and
improvements to per capita
income
  SRES B1
(Integrated, eco-friendly)
−  Rapid economic growth as
in A1, but with rapid changes
towards a service and
information economy
−  Reductions in material
intensity and the introduction
of clean and resource
efficient technologies
−  Population rising to 9 billion
in 2050 and then declining
Future global mean temperature – data and projections
for A2 emission scenario
http://mn.wikipedia.org/wiki/Image:Global_Warming_Predictions.png
Future global mean temperature – overall assessment
Downscaling from GCMs to regional scenarios
A range of approaches, including
  Statistical downscaling
  Delta method
  Regional climate models (RCMs)
⇒ A source of uncertainty
http://www.uib.no/People/gbsag/climate_model.jpg
Air temperature anomaly projections from CRCM4
forced with CGCM3 and A2 emissions scenario
Rodenhuis et al., 2009. Hydro
-climatology and future climate
impacts in British Columbia.
Pacific Climate Impacts
Consortium, University of
Victoria, Victoria BC, 132 pp.
Precipitation anomaly projections from CRCM4 forced
with CGCM3 and A2 emissions scenario
Rodenhuis et al., 2009. Hydro
-climatology and future climate
impacts in British Columbia.
Pacific Climate Impacts
Consortium, University of
Victoria, Victoria BC, 132 pp.
Climate change projections for southern BC
Values are changes from 1961-1990 normals,
based on 7 GCMs and 8 emission scenarios
2020
Winter
Summer
2050
T (oC)
P (%)
T (oC)
P (%)
0 to 2
-5 to +15
1.5 to 3.5
0 to 20
0.5 to 2
-30 to +5
1.5 to 4.0
-35 to 0
Moore, Spittlehouse, Whitfield and Stahl, in press.
Future climate scenarios – implications for British
Columbia streamflow
  Higher fall-winter-spring air temperatures
–  more precipitation falls as rain, less snow accumulation
–  earlier onset of spring snowmelt
–  earlier disappearance of snow
  Higher summer temperature, less summer rainfall
–  lower late-summer/early-autumn flows
Projected streamflow for Whiteman Creek
(Okanagan valley) based on two GCMs
CGCM2
CSIROMk2
Merritt et al., 2006. Journal of Hydrology 326: 79-108.
Historic streamflow patterns for Capilano River
during warm and cool periods
Climate change and glacier runoff
Illecillewaet
Glacier in 1889
and 2004
http://faculty.geog.utoronto.ca/Harvey/Harvey/harvey_images.htm
Streamflow per unit drainage area
Place and Eight Mile Creeks, near Pemberton, BC
― Place Creek, 25% glacier cover
― Eight Mile Creek, 1% glacier cover
Glacier runoff response to climate warming
Onset of warming
Bridge Glacier – Now and Projected
~1995
2090 “No climate change”
2005
2090 SRES A2
Columbia Icefield Area, BC-AB Border
2002
Columbia Icefield Area, BC-AB Border
2100 – CGCM3.1 A1B Scenario
Key points
  Scenarios/projections vs predictions
  Warmer in winter and summer
  Projections more variable for precipitation, though
likely wetter winters/drier summers by 2050
  Glaciers will continue
to retreat
  Qualitative changes in
hydrographs robust
  Quantitative projections
subject to considerable
uncertainty