From: on behalf of Panel Registry Subject: FW: TNG registration of ...

Table 7: Research studies ongoing in BC on streamflow.
Region Source Study Site Hydrologic
Model
Fraser Morrison
River et al.
200234 Fraser
River
Basin
(217,000
km2) UBC
Watershed
Model
Fraser
River
Sushama
et al.
2006 35
Fraser
River basin
above Port
Mann
(232,000
km 2)
Canadian
Regional
Climate
Model
(CRCM)
Source: Adapted from Merritt et al. (2006)
GCM
Scenario
CGCMA
Hadley
Climate
Model
(HadCM2)
CGCM2‐
A2
standard,
CGCM2 –
A2
updated,
and
CGCM2‐
IS92
standard
Downscaling
Technique
Statistical
climate
inversion
CRCM
(dynamical
downscaling)
Hydrology
Scenarios
Present
climate:
(1961‐
1990)
Future
climate:
2020
(2010‐
2039);
2050s
(2040‐
2069);
2080s
(2070‐
2099)
Present
climate:
( 1961‐
1990)
Future
climate:
(2041‐
2070)
Changes to
streamflow
Modest average
flow increase in
the 2080s with a
decrease in the
average
peak
flow.
General shift to
earlier peak in
the hydrograph
(approx. 24
days)
A significant
decrease in SWE
as less
precipitation
falls as snow.
Runoff is higher
during late‐fall
and early‐winter.
Spring peaks are
attenuated
and
occur earlier.
Increased
variability in the
number of days
with low‐flows.
Increased low
flows in fall.
The recent PCIC hydrology report from 2009 outlines a host of challenges and complexities
related to modeling different runoff regimes, one being the multiple sources of streamflow
that have to be accounted for (i.e. glacier‐melt and groundwater). Yet, the studies highlight
that projected changes to annual and seasonal streamflow volumes and timing are similar
across
models and approaches. 36 The following summary is provided by the PCIC report
( p.106‐108):
• “All models and approaches that deal with nival (i.e. snow­fed) systems predict an
earlier onset of the spring freshet or peak flows compared to the base case.
34 Morrison, J., Quick, M.C. and Foreman, M.G.G., (2002).
35 Sushama, L., Laprise, R., Caya,
D., Frigon, A. and Slivitzky, M.,( 2006).
36 Merritt, W.S. et al., (2006).
28