social science team update social science team update public perception of current storm surge...

Social Science Team Update

Public Perception of Current Storm Surge InformationBetty MorrowSocResearch Miami

Jeff LazoSocietal Impacts Program, NCAR

Jennifer SpragueNWS Strategic Policy and Planning

NOAA Hurricane Conference

Miami, FL – 11/30/2010

Outline

• Objectives and Storm Surge Project Overview – Jenn Sprague

• Related Studies and Literature – Betty Morrow

• Public Survey – Jeff Lazo

• Summary & Future Work

• References & Thanks

Objectives

• To explore and assess public awareness and understanding of storm surge and storm surge information

• To assess whether the NWS should develop new storm surge informational approaches to improve the communication of storm surge risk

Project Overview

Two steps with multiple phases

STEP 1• Phase 1 (completion – 11/30/10): Leverage

existing tropical cyclone efforts (HFIP, etc.)

• Phase 2 (completion – 5/31/11): Inclusion of extratropical cyclone storm surge issues

• Step 1 phases both include1. Literature Review2. Emergency Manager Interview3. Public Focus Groups4. Public Survey

Project Overview cont’d

STEP 2• FY12 funding expected, but not yet secured

• Based on information gleaned from research in Step 1

• Focus on how the public comprehends and reacts to specific components of NWS storm surge products/watches/warnings.

• Focus on whether information should be enhanced or provided in new formats (text v. graphics) or by new delivery means.

Related studies and literature: conceptual frameworkHousehold response to surge threat has 3 components:

1.Understanding the surge hazard

2. Knowing vulnerability of their area / home and family to surge, i.e. their elevation and location in relation to coast

3.Comprehending surge danger from a specific hurricane threatening their area, i.e. probability, potential impacts, etc.

1. Understanding Surge

In one exploratory study, only 2 out of 33 coastal emergency managers believed the residents in their region understood surge (Morrow 2007) Some responses:

“I don’t think they understand how bad it can be” (EM21)

“For anyone to think that staying near the Gulf is a good idea even after Camille I can’t believe people understand the threat.” (EM 4)

“I don’t think they understand the actual surge that comes in off the ocean…I don’t think they realize how water could come inland.” (EM 25)

2. Knowing Vulnerability

Of those in Cat 1 zone, about one third are each of these:

• Very concerned

• Somewhat concerned

• Not very concerned

Hampton Road VA Evacuation Study. 2010. Morrow & Gladwin through Dewberry for FEMA and USACE

n = 1599

Evacuation Survey Results

Hampton Road VA Evacuation Study. Betty Morrow and Hugh Gladwin through Dewberry. 2009.

2. Knowing Vulnerability

Coastal Georgia Evacuation Study. 2010. Morrow & Gladwin through Dewberry. 2009 for FEMA and USACE.

Each dot = one interview

Not Very Likely

Somewhat Likely

Very Likely

Likelihood Would Be Flooded in Major Hurricane:

Other Recent Findings

• In spite of forecast information most residents in path of Hurricane Ike were taken by surprise by storm surge

– Morss & Hayden 2010

• When asked what the expected sea level would be if a 15-foot surge occurs at the time of a 2-foot tide, only 19% gave the correct answer

– Morrow & Gladwin 2007

Step 1 – Phase 1 Overview1. Literature Review (in progress) Based on earlier literature review(s) conducted by

Morrow on storm surge and Lazo on hurricane preparedness

Little literature on public use of storm surge information.

2. Emergency Manager Interviews (complete) Leverage HFIP: interviews conducted with EM and

related Florida stakeholders Current EM interviews NOT intended to be all

inclusive of all coastal EMs potentially affected by storm surge.

3. Public Focus Groups (complete) Primary purpose – survey development 8 focus groups in Tampa, FL and Miami, FL and 12

individual directed interviews (IDIs) in Miami.

4. Public Survey (data collection complete)

Literature ReviewFew studies dealing explicitly with storm surge communication and understanding

Some findings:• Lack of knowledge about flood risk in general• Lack of knowledge about surge and difference

between surge and other inundation• Impact of storm surge not well understood• False sense of ability to withstand surge risk• Wind mitigation can give false sense of safety

from surge• Role of storm surge risk in evacuation decisions

mixed

Public Focus Groups

Tampa, Florida – May, 2010 “For me, I'm not worried about the

storm surge so much as winds…”

“… the waters going to go out with the wind then … like a tsunami on the beach coastal area.”

“I find it hard to believe that the water could rise and could literally go, like, five miles across…”

Purpose Primarily valuation for HFIP Storm Surge

Survey development Pre-HFIP Focus Groups – Tampa and Miami IDIs - Miami Peer review

Pretesting – Knowledge Networks Timed – 33 minutes Estimation of valuation model

Implementation – Knowledge Networks 20 minutes median

Sampling KN panel – generalizability Response rate (as per KN report)

Respondents Comparison to population - weights

Public Survey – Method

Public Survey - Sample

Responses

TX

264 LA

107 MS

12 AL

22FL

719GA

16 SC

50 NC

49TOT

1,218

POPULATION 18 years+155 counties. Pop: ~30 M

Public Survey - Sample

Gender Female 51%

Ethnicity White* 63% Black* 16% Other* 6% Hispanic 15%

Age 18-29 21% 30-49 39% 50-65 20% 65 Up 19%

Income Less than $20K 11% $20K - $49K 34% $50K - $99K 38% $100K and up 17%

Home Tenancy Own 68%

Education Less than HS 6% High School Grad 20% Some College 33% Bachelors 26% Graduate 17%

* Non-Hispanic

Survey results

1. Value of improved forecasts

2. Perceptions and information sources

3. Understanding of storm surge

4. Information preferences

Value of Improved Forecasts

Hurricane Forecast Improvement Project – Socio-Economic Impact Assessment (HFIP-SEIA )

Non-market valuation study – stated preference method (conjoint analysis)

Included “surge information” attribute

Alternative approach for assessing respondents’ preferences for information


Bivariate Probit, λ unconstrained, with a constant(n = 1201)

Expected Sign Beta t-stat WTP,

unitSt.Er. WTP Unit

Constant 0.618 8.78 $-8.84$-

8.84

Landfall Time - -0.070 -10.05 $1.01 $1.01 hours

Landfall Location - -0.011 -13.83 $0.16 $0.10 miles

Wind Speed - -0.006 -2.52 $0.09 $0.01 mphChange in Wind Speed + 0.008 12.97 $0.11 $0.03

percent

Surge Depth - 0.003 0.45 $0.04 $0.01 feet

Surge Information + 0.038 1.58 $0.54 $0.09 yes/no

Extended Forecast + 0.044 3.53 $0.63 $0.34 days

Cost - -0.070 -51.52


Bivariate Probit, λ unconstrained, with a constant(n = 1201)

Expected Sign Beta t-stat WTP,

unitSt.Er. WTP Unit

Constant 0.618 8.78 -8.840 -8.840

Landfall Time - -0.070 -10.05 $1.01 $1.01 hours

Landfall Location - -0.011 -13.83 $0.16 $0.10 miles

Wind Speed - -0.006 -2.52 $0.09 $0.01 mph

Change in Wind Speed + 0.008 12.97 $0.11 $0.03 percent

Surge Depth - 0.003 0.45 $0.04 $0.01 feet

Surge Information: $0.54 WTP per household per year

(9,857,371 households)

Extended Forecast + 0.044 3.53 $0.63 $0.34 days

Cost - -0.070 -51.52

Survey results





Perceptions

Not at all likely

Not very likely

Somewhat likely

Very likely Extremely likely

0%

10%

20%

30%

40%

50%

Likelihood of storm surge damage - by surge expo-sure

Not surge exposed Surge exposed

Not at all likely

Not very likely

Somewhat likely

Very likely Extremely likely

0%

10%

20%

30%

40%

50%

Likelihood of wind damage - by surge exposure

Not surge exposed Surge exposed

Perceptions

1

2

3

4

5

Impacts from sustained high

winds

Tornadoes associated with the

hurricane

Flooding caused by storm surge

Flooding caused by rainfall

Injuries during clean up after the

hurricane

Injuries during preparation before

the hurricane

Likelihood of loss of life due to ...(1=Not at all likely 5=Extremely likely)

Information sources

1

2

3

4

5

Use for information on potential hurricanes for decision making ...(1=Never or rarely 5=All of the time)

Survey results





Understanding of storm surge


Forec

ast -

high

wat

er m

ark

Surg

e is w

ater

from

sea

Surg

e and

tsun

amis

are t

he sa

me

Surg

e cau

sed b

y rai

n

Surg

e onl

y with

in m

ile of

coas

t

Surg

e for

ecas

ts ac

coun

t for

tide

s .

Categ

ory i

nclu

des r

ain a

nd in

land

floo

d

Surg

e prim

ary r

easo

n to e

vacu

ate

Categ

ory r

efers

to w

ind a

nd su

rge

Close

ly re

lated

to w

ind s

treng

th

1

2

3

4

5


Survey results





Information preferences

Information preferences

Separate Info Watch Warning

58.2% 55.4%65.7%

22.6% 26.3%19.6%

19.2% 18.3% 14.7%

Storm Surge Information Preferences

Yes No Don't Know

Information preferences - format

1

2

3

4

5

Maps Above ground level

Graphics showing damage .

Worded explanations

Internet Feet above sea level

Probability statements

Separate surge watch and warning

info

Usefulness of information format(1=Not at all useful 5=Extremely useful)

• Begin to explore preferences for presentation of storm surge information

Summary of findings

1. Public awareness and understanding of storm surge and storm surge information

• A significant portion of the surge vulnerable population does not understand • what storm surge is• their vulnerability to surge• what the forecast information means• the potential impacts of surge

Summary of findings

2. New storm surge informational approaches to improve the communication of storm surge risk

• Inconclusive whether there is a single best approach to communicating surge risk

• People have significant preferences for additional surge information

• Currently undefined variety of preferences for the format and delivery of information

Ongoing and future work

• Complete lit review – extend to ET aspects

• Continue survey analysis

• Summarize EM and stakeholder interviewers

• Survey EMs (for HFIP)

• Conduct public survey on ET and TC surge

References

Gladwin, H., J.K. Lazo, B.H. Morrow, W.G. Peacock, H.E. Willoughby. 2009. “Inbox: Social Science Research Needs for the Hurricane Forecast and Warning System.” Bulletin of the American Meteorological Society. 90(1):25-29.

Gladwin, H., J.K. Lazo, B. Morrow, W.G. Peacock, H. Willoughby. 2007. “Social Science Research Needs for the Hurricane Forecast and Warning System” Natural Hazards Review. 8(3): 87-95.

Letson, D., D. Sutter, J.K. Lazo. 2007. “The Economic Value of Hurricane Forecasts: An Overview and Research Needs.” Natural Hazards Review. 8(3):78-86.

Lazo, J.K. and D.M. Waldman, forthcoming. “Valuing Improved Hurricane Forecasts.” Economics Letters

Lazo, J.K., D.M. Waldman, B.H. Morrow, and J.A. Thacher. 2010. “Assessment of Household Evacuation Decision Making and the Benefits of Improved Hurricane Forecasting.” Weather and Forecasting. 25(1):207-219.

Morrow, B.H. 2007.Final Report. Storm Surge Social Science Project. Submitted to NOAA Coastal Services Center.

Morrow, B.H. and H. Gladwin 2009. Coastal GA Evacuation Study. Submitted through Dewberry to FEMA and USACE.

Morrow, B.H. and H. Gladwin. 2010. Hampton Road VA Evacuation Study. Submitted through Dewberry to FEMA and USACE.

Morss, R. E. and M. H. Hayden. 2010. “Storm Surge and ‘Certain Death’: Interviews with Texas Coastal Residents Following Hurricane Ike”. Weather, Climate and Society. 2(3): 174-189.

Thanks!

NOS / CSC – Coastal Storms Program for funding

Storm surge social science participants:

– Jesse Feyen, Jamie Rhome, Audra Luscher, Timothy Schott, Jen Sprague, Walt Zaleski, Mary Erickson, Keelin Kuipers, John F Kuhn, Daniel Noah, Jennifer McNatt, Steve Letro, Gene Hafele, Harvey Thurm, Tom Bradshaw, Jeffrey Pereira, Al Sandrik, Andy Devanas, … and multiple others from all conference calls!

Literature review: Hugh Gladwin, Suzana Mic, Emily Laidlaw

Survey review: Rebecca Morss, Julie Demuth, Mark DeMaria, Ed Rappaport

Survey implementation: Stefan Subias, Wan Yan, Mike Lawrence

Modeling and analysis: Don Waldman, Jennifer Thacher, Jennifer Boehnert

And others …

social science team update social science team update public perception of current storm surge...

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