Post on 19-Jan-2016
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Climate Change: The Move to Action(AOSS 480 // NRE 480)
Kevin Reed2133 Space Research Building (North Campus)
kareed@umich.eduhttp://www-personal.umich.edu/~kareed/
Winter 2012February 21, 2012
Class News
• Ctools site: AOSS_SNRE_480_001_W12• 2008 and 2010 Class On Line:
– http://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Action
Today
• 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 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
US CCSP Report 3.3 - 2008
e 1 k(x ) / 1/ k
• Extremes are a natural component of a stable climate.
• However, there are costs!
What is an Extreme?
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
NCDC/NOAA – State of the Climate
CEI
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
Emanuel (2007) Holland and Webster (2007)
Can be basin specific!
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
• Strong storms, but less globally.
Zhao et al. (2009)
Fra
ctio
nal C
hang
e
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
Dole et al. 2011
They see no signal of the role anthropogenic
sources
• 2010 Russian Heat Wave
Example: Heat Waves
• Potential for Future Russian Heat Waves
Dole et al. 2011
Scientific Debates
Example: Heat Waves
Barriopedro et al. 2011
• European Heat Waves (1500-2100)
2 500-year events in last decade!
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/attribution/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.”