Tales of Future Weather Wilco Hazeleger
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Tales of Future Weather
Wilco Hazeleger
The setting
IPCC special report on extremes
Actionable information from climate
models?
Limited prediction skill beyond trends
van Oldenborgh et al Clim Dyn 2012
Tales of Future Weather
Co-developed with societal actor and scientist:
• Drivers of vulnerability
– The setting, context, forcing
• Relevant analogs from current and past climate
– Statistically, physics, consequences
• Synoptic weather events in alternative (future) climate
setting
– Numerical weather prediction models (internal consistency), data
assimilation, wide range of plausible boundary conditions
• Wider scientific perspective of potential future climate
Hazeleger et al Nature Climate Change 2015
Unprecedented analogs in current
climate: multiday high winds and surge
• Problem:
– Dike reinforcement near
Amsterdam
– Design criteria inspired by extreme
water levels induced by multi-day
strong Eastern Wind
• Reconstructed analogs from
ensemble weather predictions
physically plausible extreme,
internally consistent
KNMI, van Oldenborgh, van den Brink
Unprecedented weather in current
climate: compound rain and surge
Sea level
Inland water level
Unprecedented weather in the future:
hurricanes towards Europe
Haarsma et al 2013 GRL
Current weather transformed to future
Future: less cold at same circulation
• Apply weather
forecasting techniques
to obtain 2013/2014
mean circulation in a
future climate (2090s) in
a fully coupled model
Rasmijn et al 2014 (QJRMS), 2015
Future: wetter at same circulation in UK
Rasmijn et al 2015, subm
Meteorological physics insights
e.g. Lenderink and van Meijgaard, Nature Geosc, 2008
Robust decision making
• Characterize uncertain vulnerabilities contingent on
proposed strategy
Propose
strategy
Identify
vulnerabilities
Identify and assess
options for reducing
vulnerabilities
After Lempert and Groves 2006
Tales of Future Weather
• Vivid storylines of weather that exposes vulnerability
• Co-developed between societal actor and scientist
• Unprecedented weather in current climate and any
relevant (future) climate setting
• Apply well-tested global high resolution numerical
weather prediction models and techniques
(physically plausible, internally consistent)
Thank you
MT-KS 18
Hupsel, 26-27 Augustus 2010
Intensity: 20 mm/hr
Highest daily rainfalll in E-Obs!
Humidity transport by atmospheric
rivers
“atmospheric rivers”
Predict then act
• Rank strategies contingent on characterizations of
uncertainties
Characterize
uncertainty
Rank alternative
Strategies
Conduct sensitivity
analysis
After Lempert and Groves 2006
Probability of the exceedance of the 99th percentile of NNW wind. After a 10-day precipitation extreme the probability of exceedance is approximately 0.04 (red diamond), which is a factor 4 higher than the probability of 0.01 (by construction) in the full data set (blue diamond). The increase in probability is outside the range that could be expected due to chance because of the much smaller sample size (blue bars).
T=96h T=132h T=162h
Equivalent Potential temperature (K, 850 hPa), MSLP and 250 hPa winds
Synoptic structure: warm seclusion
storms
Highest gradient on cold front vs highest gradient on Warm front (detached, t bone structure: warm seclusion)
More high resolution results: poster Ronald van Haren et al
on dynamical and thermodynamical mechanisms
Precipitation session: EGU2014-15454 (R393,
Wednesday, Red Posters, 17:30-19:30)
Related Documents
