Weather information and surface Weather information and surface transportation in Canada: transportation in Canada: The long and winding roadThe long and winding road

Brian MillsBrian Mills1,21,2, Jean Andrey, Jean Andrey22, Susan Tighe, Susan Tighe33, and Sarah Baiz, and Sarah Baiz33

11Adaptation & Impacts Research Division, Environment Canada (Brian.Mills@ec.gc.ca)Adaptation & Impacts Research Division, Environment Canada (Brian.Mills@ec.gc.ca)

22Department of Geography & Environmental Management, University of WaterlooDepartment of Geography & Environmental Management, University of Waterloo

33Department of Civil & Environmental Engineering, University of WaterlooDepartment of Civil & Environmental Engineering, University of Waterloo

IntroductionIntroduction

Impressive

Gains in

Predictability

PDP complain about process

TIGGE thought

responsible

DAOS target of unruly

observers

Shortage of planes blamed

on Thorpex campaigners

• ““Pushing the Product”Pushing the Product”

• What happens after the What happens after the

flush?flush?

• The “Bottom-up” perspective The “Bottom-up” perspective

is a necessary complement if is a necessary complement if

not starting pointnot starting point

• A few examples from road A few examples from road

transport transport

IntroductionIntroduction

• Economic and social activities in Canada are highly dependent on Economic and social activities in Canada are highly dependent on

road surface transportation—by far the most important mode road surface transportation—by far the most important mode

Value of Canada-U.S. Trade by Mode (2007)Total Trade (CA$569,821 million)

Road60%

Rail17%

Marine4%

Air5%

Other14%

Source: Transport Canada 2008

IntroductionIntroduction

• Maintaining the mobility afforded by the highway system without Maintaining the mobility afforded by the highway system without

compromising safety or environmental quality requires substantive compromising safety or environmental quality requires substantive

investments—many of which are weather-related investments—many of which are weather-related

Design, construction and maintenance of infrastructureDesign, construction and maintenance of infrastructure

OperationsOperations

EnvironmentalEnvironmental

Safety interventionsSafety interventions

02000400060008000

1000012000140001600018000

Mill

ion

s C

A$

1998

-99

1999

-00

2000

-01

2001

-02

2002

-03

2003

-04

2004

-05

2005

-06

2006

-07

Fiscal Year

Road Transportation Expenditures by Level of Government

Local Provincial/Territorial Federal

IntroductionIntroduction

Andrey 2009

• Despite numerous interventions, significant risk remainsDespite numerous interventions, significant risk remains

• Why? Imperfect decision-making? Role of wx info?Why? Imperfect decision-making? Role of wx info?

Weather & Climate-related Decisions Weather & Climate-related Decisions at Many Scalesat Many Scales

• DriversDrivers

• Public & commercial transport service providersPublic & commercial transport service providers

• Public road authoritiesPublic road authorities

• Road associations Road associations

• Construction & maintenance industryConstruction & maintenance industry

• Vehicle manufacturersVehicle manufacturers

• Vehicle repair industryVehicle repair industry

• InsurersInsurers

• Police/enforcement agenciesPolice/enforcement agencies

• Emergency responders and healthcare industryEmergency responders and healthcare industry

• Weather, road weather, and hydromet service providersWeather, road weather, and hydromet service providers

Case 1: Weather-related collision riskCase 1: Weather-related collision risk

• Robust estimates of the relative risks and social costs associated Robust estimates of the relative risks and social costs associated

with driving in inclement weather are lacking at the city-region and with driving in inclement weather are lacking at the city-region and

national scales in Canada.national scales in Canada.

• This information is fundamental to design and evaluate the efficacy This information is fundamental to design and evaluate the efficacy

of response measures such as the provision of weather of response measures such as the provision of weather

information intended to influence driver behaviour just before and information intended to influence driver behaviour just before and

during a particular trip. during a particular trip.

D. Doiran, National Post

MethodMethod

• National Transportation Accident Incident Database (TRAID) National Transportation Accident Incident Database (TRAID)

collision data (1984-2000) combined with hourly and six-hourly collision data (1984-2000) combined with hourly and six-hourly

records of precipitation (R, S, ZR/ZL, mixed) for 28 Canadian cities records of precipitation (R, S, ZR/ZL, mixed) for 28 Canadian cities

• Matched pair event-control analysis conducted producing ~ 36,000 Matched pair event-control analysis conducted producing ~ 36,000

entriesentries

• Relative risk calculations performed by dividing the sum of injury Relative risk calculations performed by dividing the sum of injury

collisions/injuries during events by corresponding counts for collisions/injuries during events by corresponding counts for

controlscontrols

• Further analysis facilitated the development of risk estimates Further analysis facilitated the development of risk estimates

disaggregated by precipitation type, amount, injury severity, disaggregated by precipitation type, amount, injury severity,

region, etc. region, etc.

ResultsResults

• Risk of injury increases by approximately 70% during precipitation Risk of injury increases by approximately 70% during precipitation

relative to dry seasonal conditionsrelative to dry seasonal conditions

• Minimal and minor injuries tend to increase more than do major Minimal and minor injuries tend to increase more than do major

and fatal injuriesand fatal injuries

• About 200-400 fatalities and several thousand injuries are About 200-400 fatalities and several thousand injuries are

attributable to weather-related motor vehicle collisions each year attributable to weather-related motor vehicle collisions each year

with an estimated social cost >CA$1 billionwith an estimated social cost >CA$1 billion

Relative Risk of Different Severities:All 28 Cities

0.0

0.5

1.0

1.5

2.0

2.5

3.0

All Rain Snow Freezing Rain Rain mixedwith Snow

Re

lati

ve

Ris

k Minimal

Minor

Major

Fatal

Andrey et al. 2005, Andrey 2009

ResultsResults

• Comparative analysis using insurance claim data (1999-2002) for Comparative analysis using insurance claim data (1999-2002) for

Winnipeg, ManitobaWinnipeg, Manitoba

• Similar results for incidents (below) and claim costs Similar results for incidents (below) and claim costs exceptexcept

Accident Benefit Costs during snowfall eventsAccident Benefit Costs during snowfall events (RR=3.33) (RR=3.33)

Mills et al., in press

TRAID and MPI Insurance Comparison for Winnipeg (1999-2002)

0.50.70.91.11.31.51.71.92.12.32.52.72.93.1

Rain-TRAID Rain-Insurance Snow-TRAID Snow-Insurance Total-TRAID Total-Insurance

Re

lati

ve

Ris

k (

od

ds

ra

tio

an

d 9

5%

CI)

Future ResearchFuture Research

• Complete RR analyses using insured loss data and weather Complete RR analyses using insured loss data and weather

warning/advisory informationwarning/advisory information

• Develop a prototype collision prediction model that can Develop a prototype collision prediction model that can

incorporate probabilistic weather prediction information and incorporate probabilistic weather prediction information and

produce a normalized indexproduce a normalized index

• Evaluate the effect of this “impact-centric” information on Evaluate the effect of this “impact-centric” information on

stated/observed driver response relative to traditional types of stated/observed driver response relative to traditional types of

weather and road weather informationweather and road weather information

Case 2: Seasonal Load Restrictions Case 2: Seasonal Load Restrictions on Ontario Highways on Ontario Highways

• Secondary roads are often subjected to heavy loads from agricultural or Secondary roads are often subjected to heavy loads from agricultural or

resource extraction (forestry, mining) operationsresource extraction (forestry, mining) operations

• Where frost penetrates into the subgrade, such highways are extremely Where frost penetrates into the subgrade, such highways are extremely

vulnerable to damage caused by brief periods of thaw-induced weakeningvulnerable to damage caused by brief periods of thaw-induced weakening

• Seasonal load restrictions (SLR) are used by transportation agencies to Seasonal load restrictions (SLR) are used by transportation agencies to

reduce/increase the permissible loads carried by trucks reduce/increase the permissible loads carried by trucks

• Fixed dates/durations are often used in establishing SLRs which provides Fixed dates/durations are often used in establishing SLRs which provides

certainty for trucking operations but can lead to tremendous damage when certainty for trucking operations but can lead to tremendous damage when

thaws occur outside of the period thaws occur outside of the period

Case 2: Seasonal Load Restrictions Case 2: Seasonal Load Restrictions on Ontario Highways on Ontario Highways

Source: MTO, 2005

MethodMethod

• Empirical model was developed to predict frost and thaw depths as Empirical model was developed to predict frost and thaw depths as

a function of simple freezing and thawing indices derived from air a function of simple freezing and thawing indices derived from air

temperaturetemperature

• Model validated and calibrated against data obtained for 2 winter Model validated and calibrated against data obtained for 2 winter

seasons at 2 instrumented test sites periodically evaluated for seasons at 2 instrumented test sites periodically evaluated for

pavement strength using a portable Falling Weight Deflectometer pavement strength using a portable Falling Weight Deflectometer

Results Results (Northeast Ontario Site)(Northeast Ontario Site)

iii

iii

TIFITD

TIFIFDii

675.0038.0494.0

6.22.41.220 0

iii

iii

TIFITD

TIFIFDii

1324848

01.085.01450

Where: i Number of days after the day indexed as day i = 0i = 0 Day on which TAir first falls below 0ºC io Day of transition from Freezing to Thawing seasonFDi Depth of frost on day (cm)TDi Depth of thaw on day (cm)FIi Freezing Index value on day (in ºC -days)TIi Thawing Index value on day (in ºC -days)

Future ResearchFuture Research

• Repeat analysis and refine models using additional winter seasons Repeat analysis and refine models using additional winter seasons

and locationsand locations

• Develop a damage model and SLR/WWP decision experiment using Develop a damage model and SLR/WWP decision experiment using

weather forecast data. Evaluate social costs and benefits as a weather forecast data. Evaluate social costs and benefits as a

function of accuracy. function of accuracy.

Case 3: Impacts of climate change on Case 3: Impacts of climate change on pavement infrastructurepavement infrastructure

• Current and past pavement designs generally assume a static climate Current and past pavement designs generally assume a static climate

whose variability can be adequately determined from records of weather whose variability can be adequately determined from records of weather

conditions which normally span less than 30 years and often less than 10 conditions which normally span less than 30 years and often less than 10

yearsyears

• Anthropogenic climate change challenges this assumption and raises the Anthropogenic climate change challenges this assumption and raises the

possibility that the frequency, duration or severity of thermal cracking, possibility that the frequency, duration or severity of thermal cracking,

rutting, frost heave and thaw weakening may be altered leading to shifts in rutting, frost heave and thaw weakening may be altered leading to shifts in

pavement deterioration rates if corrective actions are not takenpavement deterioration rates if corrective actions are not taken

MethodMethod

• Mid-century surface temperature and precipitation scenarios were Mid-century surface temperature and precipitation scenarios were

developed by statistically downscaling output from the CGCM2A2x developed by statistically downscaling output from the CGCM2A2x

and HadCM3B21 climate experiments for 17 Canadian sitesand HadCM3B21 climate experiments for 17 Canadian sites

• Scenarios were applied to 2 deterioration-relevant indicators: 1) Scenarios were applied to 2 deterioration-relevant indicators: 1)

Performance Grade Asphalt Cement (PGAC) high and low Performance Grade Asphalt Cement (PGAC) high and low

temperature threshold criteria, and 2) Freeze-thaw indicestemperature threshold criteria, and 2) Freeze-thaw indices

• Scenarios were applied at 6 sites using the Mechanistic-Empirical Scenarios were applied at 6 sites using the Mechanistic-Empirical

Pavement Design Guide (MEPDG) model which simulates life cycle Pavement Design Guide (MEPDG) model which simulates life cycle

deterioration (developed by the U.S. NCHRP and AASHTO) deterioration (developed by the U.S. NCHRP and AASHTO)

ResultsResults

• Indicator analysis suggests that low temperature cracking will Indicator analysis suggests that low temperature cracking will

become less problematic; structures will freeze later and thaw become less problematic; structures will freeze later and thaw

earlier with correspondingly shorter freeze season lengths; and earlier with correspondingly shorter freeze season lengths; and

higher extreme in-service pavement temperatures will raise the higher extreme in-service pavement temperatures will raise the

potential for rutting. potential for rutting.

-50.0

-40.0

-30.0

-20.0

-10.0

0.010.0

20.0

30.0

40.0

50.0

60.0

Base CGCM2A2x HADCM3B21

Des

ign

(98

% r

elia

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ity)

Min

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ay M

ean

Pav

emen

t T

emp

erat

ure

(°

C)

SuperpaveTmax-98%annual SuperpaveTmin-98% annual

Ontario RWIS Tmax-98%annual Ontario RWIS Tmin-98% annual

ResultsResults

• MEPDG analysis suggests that rutting (AC and total) and cracking MEPDG analysis suggests that rutting (AC and total) and cracking

(longitudinal and alligator) issues will be exacerbated by climate change(longitudinal and alligator) issues will be exacerbated by climate change

• Maintenance, rehabilitation or reconstruction will be required earlier in the Maintenance, rehabilitation or reconstruction will be required earlier in the

design life design life

• Absolute impacts of climate change are closely associated with the Absolute impacts of climate change are closely associated with the

underlying structural, material, and traffic characteristics of a particular site underlying structural, material, and traffic characteristics of a particular site

thus generalizations must be considered with caution. thus generalizations must be considered with caution.

0

1

2

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8

9

10

1 13 25 37 49 61 73 85 97 109

121

133

145

157

169

181

193

205

217

229

Month

AC

Ru

ttin

g (

mm

)

Baseline CGCM2A2x scenario HadCM3B21 scenario

Future ResearchFuture Research

• Repeat MEPDG analysis using the latest AR4 climate change Repeat MEPDG analysis using the latest AR4 climate change

scenarios, more sophisticated downscaling, and a greater range of scenarios, more sophisticated downscaling, and a greater range of

pavement structures and vehicle loadspavement structures and vehicle loads

• Incorporate municipal distress data and a ravelling (pothole) Incorporate municipal distress data and a ravelling (pothole)

indicator into the analysisindicator into the analysis

• Examine utility of monthly-seasonal scale forecastsExamine utility of monthly-seasonal scale forecasts

Further ReadingFurther Reading

Andrey, J, B. Mills, D. Unrau, M. Christie and S. Michaels 2005. Toward a National Andrey, J, B. Mills, D. Unrau, M. Christie and S. Michaels 2005. Toward a National

Assessment of the Travel Risks Associated with Inclement Weather, ICLR Paper Assessment of the Travel Risks Associated with Inclement Weather, ICLR Paper

Series, Institute for Catastrophic Loss Reduction, London, Ontario. 35 pp. Series, Institute for Catastrophic Loss Reduction, London, Ontario. 35 pp.

Baiz, S., S. Tighe, C.T. Haas, B. Mills, and M. Perchanok, 2008. Development of frost and Baiz, S., S. Tighe, C.T. Haas, B. Mills, and M. Perchanok, 2008. Development of frost and

thaw depth predictors for decision making about variable load restrictions, thaw depth predictors for decision making about variable load restrictions,

Transportation Research Record, 2053:1-8. Transportation Research Record, 2053:1-8.

Mills, B., S.L. Tighe, J. Andrey, J.T. Smith, and K. Huen, 2009. Climate change implications Mills, B., S.L. Tighe, J. Andrey, J.T. Smith, and K. Huen, 2009. Climate change implications

for flexible pavement design and performance in southern Canada, Journal of for flexible pavement design and performance in southern Canada, Journal of

Transportation Engineering, 135(10). Transportation Engineering, 135(10).

Thank you!Thank you!