Evaluating the impacts of climate change on hydrology and water resources
Phil Graham
Fredrik Wetterhall
Swedish Meteorological and Hydrological Institute
Norrköping
What are our main objectives?
• investigate impacts of climate change on stream
discharge by transferring the climate change signal
from RCMs to hydrological rainfall-runoff models
• identify areas at risk to both changes in flooding
and drought conditions
• conducted in the Nordic Region at varying scale
– continental scale: entire Baltic Sea Basin
– regional scale: entire national territory of Sweden
– basin scale: individual drainage basins in Sweden
Studies at Varying Scales
Link to work package objectives?
• Response surfaces for selected
applications
• Direct use of multiple regional model
projections
• Comparison of outcomes from the two
methods
What have we achieved?
Response Surfaces - Runoff
Lake Mälaren Lule River
RS - Flood Frequency
Lake Mälaren Lake Vänern
RS - Lake Levels
Lake Mälaren
Low levels
RS - Extended Period with Maximum
Discharge
Lake Vänern
Current regulation rules Proposed regulation rules (earlier releases)
WP 6.2 Tasks
6.2.8 construction of response surfaces
6.2.9 scenario impacts and risk
assessment
6.2.11 application of Ensembles
Prediction System
D6.7 & D6.13
Questions for Discussion
• How should we deal with seasonality using
the response surface approach?
• What is the proper level of detail for critical
thresholds?
• What will we actually get from the climate
models (i.e. probabilistic info.)?
• How to choose which transient simulations
to use with direct impacts simulations?
Questions for Discussion
Creating seasonally dependent sensitivity surfaces?
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1 3 5 7 9 11
Month
Pc
orr
ec
tio
n RCAO-E/A2
RCAO-E/B2
RCAO-H/A2
RCAO-H/B2
Medel
Precipitation Temperature
0
1
2
3
4
5
6
1 2 3 4 5 6 7 8 9 10 11 12
Month
del
taT
(K
)
Questions for Discussion
Creating seasonally dependent sensitivity surfaces?
Precipitation Temperature
0.6
0.8
1
1.2
1.4
1.6
1.8
1 2 3 4 5 6 7 8 9 10 11 12
Month
Co
rre
ctio
n fa
cto
r
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
1 2 3 4 5 6 7 8 9 10 11 12
Month
Co
rre
ctio
n fa
cto
r
Continuous Simulations(transient)
1961-2100
Change in river flow
(10-yr running mean)
compared to 1961-1990
RCA3sres-A2
Continuous Simulations(transient)
1961-2100
Change in river flow
(10-yr running mean)
compared to 1961-1990
RCA3sres-A2
Continuous Simulations(transient)
Work in
Progress!
1961-2100
Change in river flow
(10-yr running mean)
compared to 1961-1990
RCA3sres-A2sres-B2
Modelled Change in
Hydropower Potential
for the Lule River
2071-2100compared to
1961-1990
Modelled Change in
Hydropower Potential in Sweden
2071-2100compared to
1961-1990