Presentation on theme: "Lessons from the Warning Project Eve Gruntfest Kansas City January 22, 2009."— Presentation transcript:
Lessons from the Warning Project Eve Gruntfest Kansas City January 22, 2009
The Big Thompson Flood in Colorado July 31, 1976 o140 lives lost – 35 miles from Boulder oStudied the behaviors that night oWho lived? oWho died? oLed to detection & response systems Focus on flash floods & warning systems
Our National Science Foundation project aimed to oEvaluate impacts of oDemographic change oNew & different sources of information oTest conventional wisdom about oFalse alarms/ close calls Evaluate previous trauma experience & warning perceptions
What we know about warnings – Public response components oHear/receive oUnderstand oBelieve oPersonalize oDecide to act oRespond Reinforcing what Havidan said this morning: The warning process is complex
Why Austin & Denver Similarities Large Growing cities Diverse populations Vulnerable to flash flooding
Warning project methodology oSurvey Development o1 year oInput from officials & hazards researchers oSurvey format oLikert scale & true/false oDemographic questions oExperience with flash floods & trauma oSurveys in English & Spanish to selected respondents oSurvey is available – for follow up studies
Mail survey o6000 surveys sent to residents in or near the floodplain o1017 surveys returned
oWhere do people get their weather information? oBest way for officials to warn you about a flash flood?
All sources of weather information used n=935
Most important source of weather information N=945
A flash flood warning indicates a more serious threat than a flash flood watch 92% 8% n=1031
I take flash flood warnings seriously n= % 8%
The best way for officials to warn you about a flash flood? 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
Realizing it’s difficult to predict flash floods, I prefer more warnings even if there are more false alarms or close calls N= 1047
Austin by Gender Realizing 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
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 oSmaller area under warning oIs there a best leadtime? oConcerns with “too much leadtime?” oAre these warranted?
We need new metrics –Socially relevant verification Forecast verification is difficult in rural areas
Prairie dogs don’t answer the phone
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 63% say they would NOT DRIVE through it Is this good or bad news?
Tailor message for local hazards - -Maricopa County (Phoenix, AZ) oFloodwaters can conceal a damaged roadway oFlash Floods rarely last more than an hour oDon’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 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 oIntentional drivers: purpose was to film the flood water, or to drive in the flood water (for fun). 59% (n=31) oSituational drivers: purpose of trip was based upon their current situation, like driving to or returning from work. 41% (n=21)
Purpose of Trip
SOURCES OF WEATHER INFORMATION
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” oFolks >50 years old most vulnerable to severe manifestations oCampaign 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 see Easy 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
Las Vegas Billboards
Warning project publications Environmental Hazards Vol 7 oC. Benight, E. Gruntfest, M. Hayden, L. Barnes Trauma and short-fuse weather warning perceptions oS. Drobot C. Benight, E. Gruntfest Risk factors for driving into flooded roads oM. Hayden, S. Drobot, S. Radil, C. Benight, E. Gruntfest, L. Barnes Information sources for flash flood warnings in Denver, CO and Austin, TX oI.Ruin, J-C. Gaillard, C. Lutoff How to get there? Assessing motorists’ flash flood risk perception on daily itineraries