Presentation by Umit Taner (Deltares, Netherlands) at the Hydrology Suite User Days (Day 1) - Hydrology Suite introduction and River Basin Management software (RIBASIM), during the Delft Software Days - Edition 2023 (DSD-INT 2023). Tuesday, 28 November 2023, Delft.

1. Integrating Model Builders, Data, and Cloud Computing:
A Global Climate Stress Testing Tool
for Water Practioners
International User Days
Deltares Hydrology Software Suite
November 28, 2023
M. Umit Taner, PhD

2. 2
We are already witnessing climate change
but the projections are highly uncertain….

3. 3
Now Future
Uncertainty
Projected
Most-likely
Black
swans
Possible,
But less likely
A robustness-based approach to climate risk
Consider a wide range of
plausible futures

4. 4
Now Future
Uncertainty
Vulnerable
Robust
A robustness-based approach to climate risk
Consider a wide range of
plausible futures
Stress test your system.
Identify sensitivity & causes
of vulnerability

5. 5
Consider a wide range of
plausible futures
Stress test your system.
Identify sensitivity & causes
of vulnerability
Develop adaptation actions
to increase robustness
Now Future
Uncertainty
Reduced
vulnerability
Increased
Robustness
A robustness-based approach to climate risk

6. Climate stress testing*
Define vulnerability
metrics criteria &
* Brown et al., 2013

7. From case studies to a global web application…
7
Example applications (2013 – 2023)
• Domestic water supply risk, San Francisco
• Environmental flows, New England/Canada
• Hydropower design, Nepal & Malawi
• IWRM & irrigation planning, Niger Basin
• Reservoir sizing, Mombasa, Kenya
• …
Climate Stress Testing Tool
✓ Joint-initiative with World Bank
Deltares to enable the approach to
common water practioners
✓ Automated workflows to apply the
method at virtually anywhere
✓ Integration of tools for rapid model
building, data processing and viz
✓ Connection to global climate
(CMIP6, ERA6, CHIRPs) and
nonclimate datasets
✓ Computations on the cloud

8. 8
CST Tool: some answers we can learn
➢ Discharge sensitivity to
∆temp and ∆precip
➢ Effect of earlier snow melt
on spring flows due to
warming
➢ Understand where low flow
criteria is violated
➢ Plausibility of occurrence
based on climate
projections
Now
GCM projections
(2035-2065)

9. 9
CST Tool – Software architecture
Request
Response
Web client Web service
Mongo
DB
Open-source python-
based workflow
management system
User input
• Project area
• Hydrological
variables
• Stress test
parameters
• Vulnerability
thresholds
• …
HYDROMT
Open-source python-package to build,
modify, analyze geospatial models
WEATHERGENR
Open-source R-package to simulate
daily, multi-grid, multi-variable series
WFLOW
Open-source spatially-distributed
hydrological modeling framework
Tools

10. CST Tool – Software architecture
Workflow management
Workflow #2
Climate Projections
2.1 Extract multigrid
GCM time-series
2.2 Spatial & temporal
average timeseries
2.3 Calculate annual
and monthly statistics
Workflow #1
Project Creation
1.1 Delineate basin &
extract gridded data
1.2 Build distributed
hydrological model
1.3 Simulate for
reference period
1.4 Inspect model’s
goodness-of-fit
Workflow #3
Stress Testing
3.1 Create historical
weather realizations
3.2 Perturb realizations
to reflect CC
3.3 Simulate hydrology
response & indicators
3.4 Create interactive
response surfaces
Gridded data

11. GUI steps
11
1 Create project
Delineate project area
Define critical locations for risk analysis

12. 12
1 Create project
Delineate project area
Define critical locations for risk analysis
2 Build and evaluate models
Deploy a wflow model with choice of gridded data
Evaluate against observed streamflow data
GUI steps

13. 13
1 Create project
Delineate project area
Define critical locations for risk analysis
2
3
Build and evaluate models
Deploy a wflow model with choice of gridded data
Evaluate against observed streamflow data
Define & execute stress test
Analyze CMIP6 projections
Decide on how to vary climate statistics
Changes in temperature
Changes in rainfall variability
Changes in dry and wet spells
….
GUI steps

14. 14
1 Create project
Delineate project area
Define critical locations for risk analysis
2
3
4
Build and evaluate models
Deploy a wflow model with choice of gridded data
Evaluate against observed streamflow data
Define & execute stress test
Analyze CMIP6 projections
Decide on how to vary climate statistics
Interactively assess climate risk
Set critical thresholds
Identify climate vulnerabilities
∆
Precip
(%)
∆ Temp (°C)
Performance
GUI steps

15. Next steps & future directions
15
➢ Initial prototype complete, cloud migration planned for Q1/2 2024
➢ Rigorous testing and feedback from early users
➢ Potential power-user integrations for 2024:
• Water system models (RIBASIM)
• Groundwater (MODFLOW)

16. Questions?
umit.taner@Deltares.nl