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Lessons from the Warning Project
Eve Gruntfest [email protected] Kansas City January 22, 2009
The Big Thompson Flood in Colorado July 31, 1976
o 140 lives lost – 35 miles from Boulder
o Studied the behaviors that night o Who lived?o Who died?o Led to detection &
response systems
Focus on flash floods & warning systems
Our 2003-2008 National Science Foundation project aimed to
o Evaluate impacts of o Demographic
changeo New & different sources of
informationo Test
conventional wisdom abouto False alarms/
close calls
Evaluate previous trauma experience & warning perceptions
What we know about warnings – Public response components
o Hear/receiveo Understando Believeo Personalizeo Decide to acto Respond
Reinforcing what Havidan said this morning: The warning process is complex
Warning project methodology
o Survey Development o 1 yearo Input from officials & hazards researchers
o Survey formato Likert scale & true/falseo Demographic questionso Experience with flash floods & traumao Surveys in English & Spanish to selected
respondents
o Survey is available – for follow up studies
o Where do people get their weather information?
o Best way for officials to warn you about a flash flood?
All sources of weather information used
81%
44%
11% 9% 10%
1%
68%
42%
14%
4%
36%
75%
90%
5%
25%
75%
92%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Televi
sion
Enviro
nmen
tal c
ues
Local r
adio
sta
tions
The W
eath
er Chan
nel
Inte
rnet
NOAA wea
ther r
adio
Wea
ther
Bug
Other
Cell P
hone
Denver
Austin
n=935
Most important source of weather information
46%
21%18%
6%2%
5%
49%
15%12% 12%
7% 4%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Local T
V
Enviro
nmen
tal C
ues
Local R
adio
The W
eath
er C
hannel
NOAA Wea
ther
Rad
io
Inte
rnet
DenverAustin
N=945
A flash flood warning indicates a more serious threat than a flash flood watch
0%10%20%30%40%50%60%70%80%90%
100%
Agree Disagree
92%
8%
n=1031
I take flash flood warnings seriously
0%10%20%30%40%50%60%70%80%90%
100%
Agree Disagree
n=1017
92%
8%
The best way for officials to warn you about a flash flood?
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Sirens Phone TV Cometo door
Radio NOAAradio
Email Cellphone
2:30 am11:00 am5:00 pm
N=1020
Is overwarning a problem: False alarm issues --”cry wolf” may not be a major problem
• People prefer more warnings even if there are more false alarms
• No measurement of “close calls” & “near misses”
• Events occur but not exactly in the warning areas or with exactly the predicted intensity
• How about new categories? New
metrics?
Officials are too sensitive to the possibility of flash flooding
N = 1031
86%
14%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Agree Disagree
Realizing it’s difficult to predict flash floods, I prefer more warnings even if there are more false alarms or close calls
N= 1047
78%
22%
0%10%20%
30%40%50%60%70%
80%90%
100%
Agree Disagree
Austin by GenderRealizing it’s difficult to predict flash floods, I prefer more warnings even if there are more false alarms or close calls
X² =4.150, p <.05
82%
18%
74%
26%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Agree Disagree
Male
Female
Extreme speed of
watershed responses
Extremely short lead-
time for warnings
New ways of representing what we know – include hydrology - Isabelle Ruin new time/space analysis
Challenging our assumptions - For flash floods – shorter lead time may be better than longer lead time
o Smaller area under warning
o Is there a best leadtime?
o Concerns with “too much leadtime?”
o Are these warranted?
We need new metrics –Socially relevant verification Forecast verification is difficult in rural areas
Since not all meteorological hazards are created equally
---What are acceptable levels of risk?
Infrastructure is aging! (levees for category 2,3,4,5?)
--- How do we measure warning success? If 20 people die in Greensburg, KS – warnings can still have saved hundreds
I would drive through an intersection with six inches of water running across it
4%
38% 39%
24%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
Strongly agree Agree Disagree Stronglydisagree
63% say they would NOT DRIVE through it
Is this good or bad news?
Tailor message for local hazards --Maricopa County (Phoenix, AZ)
o Floodwaters can conceal a damaged roadway
o Flash Floods rarely last more than an hour
o Don’t trade an hour for a lifetime
Challenge of confronting ads from car companies
How to convince people they are better Wet than Dead?
Ad says: Warning: use the cup holders at your own risk
Behavioral survey project
Observe driver’s behavior at low water crossings in Texas
Quantitative survey• Use of video• car counting
Qualitative survey• Use Youtube video,
travels log & in-depth interviews
http://70.253.207.10/view/index.shtml
WHAT WERE THEY THINKING? USING TO OBSERVE
DRIVER BEHAVIOR CROSSING FLOODED ROADS
2009 Geography Master’s thesis by Cedar League
INTENTIONAL/SITUATIONAL
o Intentional drivers: purpose was to film the flood water, or to drive in the flood water (for fun). 59% (n=31)
o Situational drivers: purpose of trip was based upon their current situation, like driving to or returning from work. 41% (n=21)
Are warnings always possible? Do they always make THE difference?
Sirens – Technical capability for smaller than county warning – But whole county hears sirens?
West Nile Virus study epidemiology-
awareness example
Nobody identifies themselves as “elderly”
o Folks >50 years old most vulnerable to severe manifestations
o Campaign for elderly
How do we address nuisance events vs catastrophic events? Height of the 1997 Fort Collins flash flood
Warning project findings
•Weather information requirements of each user community are highly specialized
•The weather research community has not focused on the individual needs of specific user communities
•Existing social science studies barely scratch the surface – more comprehensive studies must be done to have more confidence in policy change based on findings
In 2018 – yet another decade from now…When we meet – we must seeEasy natural collaborations between physical scientists, planners, engineers, broadcasters, emergency managers, social scientists & others
Fewer deaths & reduced losses from weather events & a better understanding of how people use weather information
Warning project publications Environmental Hazards 2007 -- Vol 7
o C. Benight, E. Gruntfest, M. Hayden, L. Barnes Trauma and short-fuse weather warning perceptions
o S. Drobot C. Benight, E. Gruntfest Risk factors for driving into flooded roads
o M. Hayden, S. Drobot, S. Radil, C. Benight, E. Gruntfest, L. Barnes Information sources for flash flood warnings in Denver, CO and Austin, TX
o I.Ruin, J-C. Gaillard, C. Lutoff How to get there? Assessing motorists’ flash flood risk perception on daily itineraries