AOSS_NRE_480_L22_Extremes_Uncertainty_Planning_20140410.ppt
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Climate Change: The Move to Action
(AOSS 480 // NRE 480)
Richard B. Rood / Kevin Reed
Winter 2014
April 10, 2014
Class News
• Ctools site: AOSS_SNRE_480_001_W14
• Something I am playing with
– http://openclimate.tumblr.com/
• Project Presentations
– April 22 nd …
– Final Slide Package and Narrative
• April 28, 2014 11:59 pm
Politics of
Dismissal Entry
Model
Uncertainty
Description
The Current Climate (Released Monthly)
• Climate Monitoring at National Climatic
Data Center.
– http://www.ncdc.noaa.gov/oa/ncdc.html
• State of the Climate: Global
Today: Planning and Uncertainty
• Planning Scenario
• Uncertainty
• Extremes Again
– What Are Extreme Events?
– Are They Changing?
– Will Extremes Differ With ‘Climate Change’?
• Communication
Uncertainty Discussion
• How uncertain do you think climate science is?
• What seems most uncertain to you?
• Is this uncertainty small enough to motivate
action, or is it so large that action is risky?
• Is better communication of uncertainty what
stands between us and doing something?
• Is reducing uncertainty critical?
Take this scenario
• You are asked to be the climate person of
a project to
– Forest management in a Great Lakes
National Park
– Flood management in a city in New England
• How would you start frame this problem?
• What would you say about uncertainty?
Brainstorm / Skills / Knowledge
• Motivation
• Convincing
• Data
– Past, future
• Impacts
• Uncertainty
Precipitation Extreme Events in U.S.
Basic physics
of temperature
ncrease is
very simple,
noncontroversial.
This represents the uncertainties in
the observations
Note: There
is
consistency
from many
models,
many
scenarios,
that there wil
be warming.
(1.5 – 5.5 C)
Also, it’s still
going up in
2100!
Science: Knowledge and Uncertainty
Knowledge from Predictions
Motivates
policy
Uncertainty of the Knowledge
that is Predicted
1) Uncertainty always exists
2) New uncertainties will be revealed
3) Uncertainty can always be used to
keep policy from converging
Policy
Science: Knowledge and Uncertainty
Knowledge from Predictions
Motivates
policy
Uncertainty of the Knowledge
that is Predicted
Policy
1) Uncertainty always exists
2) New uncertainties will be revealed
3) Uncertainty can always be used to keep
policy from converging
What we are doing now is, largely, viewed as successful. We are reluctant to
give up that which is successful. We are afraid that we will suffer loss.
The Uncertainty Fallacy
• That the systematic reduction of scientific
uncertainty will lead to development of
policy is a fallacy.
– Uncertainty can always be used to keep
policy from converging.
– That is – this is a political issue
• Practitioners more often want uncertainty
descriptions and context-based
descriptions rather than quantification.
Attribution
• How do we know climate change, the
warming planet, is due carbon dioxide?
Scientists and Uncertainty for Decision Makers
• Scenario Uncertainty: How much CO2 we
will emit.
• Model Uncertainty: Weaknesses of model
to represent physical, chemical and
biological processes.
• Internal Variability: Variability of the
climate, not related to human-made
changes.
NRC Modeling Report: Uncertainty
UNCERTAINTY
Uncertainty is fundamental to all scientific investigations, and many scientific
experiments are designed solely to quantify the uncertainty (e.g., in order to place
bounds on observational requirements). Many enterprises have embraced the fact that
uncertainty exists and have developed methods for operating and decision making
under uncertainty. Uncertainty, in its most general definition, refers to lack of
knowledge, or imperfect knowledge about specific quantities (e.g., speed of light), or
the behavior of a system (e.g., the climate system). Because there is often a random
component to uncertainty, it is usually broken down into two basic types:
aleatory(randomness) and epistemic (lack of knowledge about something that is in
principle knowable). With respect to climate modeling, both types of uncertainty are
highly relevant. Uncertainty in climate modeling has been discussed in many contexts
(e.g., Hawkins and Sutton, 2009; IPCC, 2007c; Palmer et al., 2005). The main
uncertainties discussed are value uncertainty (e.g., uncertainty in data such as
observations needed for model development and evaluation), structural uncertainty
(e.g., incomplete understanding of processes or how to model them), and
unpredictability (chaotic components of the complex system).
Academics and Scientists on Uncertainty
• Lack of knowledge or imperfect
knowledge
• Two categories?
– Aleatory: Dependent upon chance /
randomness
– Epistimic : Knowledge based / could be
knowable
Academics and Scientists on Uncertainty
• “Climate Scientists”
– Value uncertainty
– Structural uncertainty
– Predictability
Academics and Scientists on Uncertainty
• “Climate Scientists” through eyes of a
model practitioner
– Scientific goal to get answer for the right reason
rather than get the right number
• Sources of Uncertainty
–
–
–
–
–
–
Boundary conditions
Initial conditions
Structural formulation of physics
Parametric uncertainty
Numerical formulation
Downscaling and scaling noise
Academics and Scientists on Uncertainty
• Rood in a DoE Strategy Document
– Quantifying primary variable uncertainty (e.g.,
temperature) and integrated responses (e.g.,
sea-level rise) and presenting this information
in a way suitable for risk analysis.
– Addressing uncertainty related to biases and
misrepresentation of the variability of multiscale, coupled processes and phenomena in
climate models (e.g., mean state tropical
biases and sea ice).
Academics and Scientists on Uncertainty
• Rood in a DoE Strategy Document
– Addressing uncertainty related to
mechanisms and processes known to be
missing from climate models (e.g., ice sheet
models and groundwater flow).
– Exploring uncertainty related to specification
of emission scenarios and, more generally,
human enterprise.
Some Uncertainty References
• Climate Change Science Program, Synthesis
Assessment Report, Uncertainty Best Practices
Communicating, 2009
• Climate Change Science Program, Synthesis
Assessment Report, Transportation Gulf Coast, 2008
• Moss and Schneider, Uncertainty Reporting, 2000
• Pidgeon and Fischhoff, Communicating Uncertainty,
2011
• Lemos and Rood, Uncertainty Fallacy, 2010
• NRC Advancing Climate Modeling: Chapter 6
• Briley et al., Process Uncertainty, 2014 (in revision)
• Tang and Dessai, Usable Science, 2012
Today: Planning and Uncertainty
• Planning Scenario
• Uncertainty
• Extremes Again
– What Are Extreme Events?
– Are They Changing?
– Will Extremes Differ With ‘Climate Change’?
• Communication
Extreme Weather Events
What is an Extreme?
• Categorizing an event as
“extreme” is a somewhat
arbitrary procedure.
– What is extreme at
one space and time
may be typical at
e
another.
– Extremes are at the
tails of the distribution.
How is “tail” defined?
– Does extreme mean
“rare” or simply high
impact?
• Generalized Extreme
Value Theory
1/ k
- [1-k(x-x )/ a ]
US CCSP Report 3.3 - 2008
What is an Extreme?
• Extremes are a natural component of a stable climate.
• However, there are costs!
US CCSP Report 3.3 - 2008
Trends
Temperature
Precipitation
NCDC/NOAA – State of the Climate
Trends – Tornadoes?
NCDC/NOAA – State of the Climate
Trends – Snow?
NCDC/NOAA – State of the Climate
Trends – Tropical Cyclones?
NCDC/NOAA – State of the Climate
Trends – Tropical Cyclones?
NCDC/NOAA – State of the Climate
Trends - Issues
• Data reliability
– Technology, Coverage
• Natural Variability
• Regional Distributions
• Is there an anthropogenic signature?
Trends
• 2011 was a record-breaking year for Climate Extremes
2011 Extremes
• 14 Events of >$1 Billion in Damage
• Effective Communication?
NOAA News
2011 Extremes
NCDC/NOAA – State of the Climate
2011 Extremes - Ranks
NCDC/NOAA – State of the Climate
U.S. Climate Extreme Index
CEI
NCDC/NOAA – State of the Climate
Communication
• This is one agency’s (NOAA) at
communicating extreme events and trends to
the public?
• Is one of the figures particularly effective?
• As a whole?
• Other sources:
– NOAA – Extreme Weather 2011
– Natural Resources Defense Council
– Wunderground – Expert Blogs
How Might Extremes Change?
US CCSP Report 3.3 - 2008
How Might Extremes Change?
• Changes may be
more complex
IPCC SREX
Weather and Climate Extremes in a
Changing Climate
US CCSP Report 3.3 - 2008
Projected Precipitation Changes
US CCSP Report 3.3 - 2008
Possible Changes in Hurricanes
Can be basin specific!
Emanuel (2007)
Holland and Webster (2007)
Weather and Climate Extremes in a
Changing Climate
• In general, similar to
IPCC AR4 and IPCC
SREX results.
• Specific to North
America.
US CCSP Report 3.3 - 2008
Importance?
• For U.S.
• Cost are increasing
for many reasons:
– Population growth
– Where people live
– Changes in
extremes (as
shown)
– Vulnerability
(building codes)
US CCSP Report 3.3 - 2008
IPCC Special Report on Extremes
Are These Reports Effective?
• There are differences in the presentation
of information.
• Is one more effective than another?
• What are the strengths?
• Room for improvement?
• How is it different when compared to
IPCC AR4?
Example: Hurricanes
Fractional Change
• Strong storms, but less globally.
Zhao et al. (2009)
Example: Hurricanes
• This is important because:
Meyer et al. (1997)
Example: Hurricanes
• Also… adaptation…
US CCSP Report 3.3 - 2008
Example: Heat Waves
• Barriopedro et al., Russian Heat Wave,
Science, 2011
• Dole et al., Russian Heat Wave, GRL,
2011
• Rahmstorf, Increase of Extreme Events,
PNAS, 2011
• Shearer and Rood, Earthzine, 2011
Example: Heat Waves
• 2010 Russian Heat Wave
They see no signal of the
role anthropogenic
sources
Dole et al. 2011
Example: Heat Waves
• Potential for Future Russian Heat Waves
Scientific Debates
Dole et al. 2011
Example: Heat Waves
• European Heat Waves (1500-2100)
2 500-year events in last
decade!
Barriopedro et al. 2011
Example: Heat Waves
More Communication
• These case studies demonstrate that there is
an attempt to ‘simplify’, or communicate the
science to the public, in the reports that we
have read in class.
• NCAR – AtmosNews
– http://www2.ucar.edu/atmosnews/attributi
on/steroids-baseball-climate-change
– Deliberate attempt to increase communication
with public.
• “It’s not the right question to ask if this
storm or that storm is due to global
warming, or is it natural variability.
Nowadays, there’s always an element of
both.” Kevin Trenberth – NCAR
Shearer and Rood (2011)
• Scientist are part of the conversation…
should help frame better questions.
• Two different realities, natural and the
anthropogenically changed… this does
not exist.
• “The result is that scientific debates that
were historically carried out in the slow
deliberations of peer-reviewed journals
are now on public display and can be
misrepresented.”