Senate 110-1199. June 24, 2008. Climate change impacts on the transportation sector. U.S. Senate Hearing.
Excerpts from this 135 page document follow.
DANIEL K. INOUYE, U.S. SENATOR FROM HAWAII
The transportation sector is a major indicator of the overall economic health of our Nation. Given that fact, it is important to recognize that climate affects the design, construction, safety and operations, and maintenance of transportation infrastructure and systems. For example, as we will hear today, predicted increases in precipitation and frequency of storms will impact our transportation systems; recent flooding in the Midwest resulted in submerged highways and railroad bridges, and significant diversion of freight traffic. In addition, severe storms have caused major airport delays around the country. While there is a need for the transportation sector to adapt to the environmental changes brought on by global climate change, it is also widely recognized that the transportation sector has contributed to the causes of climate change. (1) Transportation sources account for approximately one-third of U.S. greenhouse gas emissions.
Dr Thomas C. Peterson, Climate Services Division, National Climatic Data Center, National Environmental Satellite, Data & Information Service, National Oceanic & Atmospheric Administration, U.S. Department of Commerce
I am an author of a National Research Council (NRC) commissioned paper released this past March on Climate Variability and Change with Implications for Transportation, along with other colleagues from NOAA and the Department of Energy’s Lawrence Berkeley National Laboratory. My testimony will draw from the NRC paper as well as from 3 other timely reports of which I am an author of the report on climate extremes: The Potential Impacts of Climate Change on U.S. Transportation by the NRC Transportation Research Board (TRB) which was released March 11, 2008. Impacts of Climate Variability and Change on Transportation Systems and Infrastructure—Gulf Coast Study, U.S. Climate Change Science Program (CCSP) Synthesis and Assessment Report 4.7, released March 12, 2008. Weather and Climate Extremes in a Changing Climate, U.S. Climate Change Science Program Synthesis and Assessment Report 3.3, released June 2008. Climate Change and Its Impacts on Transportation Operation and Infrastructure.
According to the NRC report, 5 aspects of climate change impact transportation operations and infrastructure: (1) increases in very hot days and heat waves, (2) increases in Arctic temperatures, (3) rising sea levels, (4) increases in intense precipitation events, and (5) increases in hurricane intensity.
Increases in Very Hot Days and Heat Waves
Impacts on infrastructure include rail-track deformities, thermal expansion on bridge joints and paved surfaces, and concerns regarding the integrity of pavement. Very hot days can have an impact on operations by limiting periods of outdoor railroad track maintenance activity due to health and safety concerns.
It is highly likely (greater than 90% probability of occurrence) that heat extremes and heat waves will continue to become more intense, last longer, and be more frequent in most regions during the twenty-first century. In 2007, the probability of having 5 summer days at or above 43.3 °C (110 °F) in Dallas was about 2%. In 25 years the models indicate that this probability increases to 5%; in 50 years, to 25%; and by 2099, to 90%. High temperatures can have a big impact on aircraft by influencing the limits on payload and/or canceling flights. This is due to the fact that, because warmer air is thinner (less dense), for any given take-off speed the wings of airplanes create less lift when temperatures are high. This causes lower lift-off load limits at high-altitude or hot-weather airports with insufficient runway lengths.
Increases in Arctic Temperatures. Impacts on infrastructure include a short season for ice on roads and thawing of permafrost, which causes subsidence of roads, rail beds, bridge supports, pipelines, and runway foundations. A longer ocean transport season and more ice-free ports in northern regions, as well as the possible availability of a northern sea route, or a northwest passage.
The Gulf Coast Study estimates that a relative sea level rise of 0.5 to 4 feet is quite possible for parts of the Gulf Coast within 50 years, due primarily to land subsidence. With an increase of 4 feet in relative sea level, as much as 2,400 miles of major Gulf Coast roadways could be permanently flooded without adaptation measures. Other impacts of sea level rise include more frequent interruptions in coastal and low-lying roadway travel and rail service due to storm surge. Sea level rise will cause storm water levels to be higher and flow further inland, exposing more infrastructure to destructive wave forces. Higher storm water levels will in turn require reassessment of evacuation routes, changes in infrastructure design, siting, and development patterns, and the potential for closure or restrictions at several of the top 50 airports, as well as key maritime ports that lie in coastal zones. With 50% of the population living in the coastal zone, these airports and ports provide service to the highest-density populations in the United States. Impacts on infrastructure include reduced clearance under bridges; erosion of road base and bridge supports; inundation of roads, rail lines, subways, and airport runways in coastal areas; more frequent or severe flooding of underground tunnels and low-lying infrastructure; and changes in harbor and port facilities to accommodate higher tides and storm surges.
Increases in Intense Precipitation Events. It is very likely (greater than 90% probability of occurrence) that intense precipitation events will continue to become more frequent in widespread areas of the United States. Impacts include increased flooding of evacuation routes, increases in weather-related delays and traffic disruptions, and increases in airline delays due to convective weather. Impacts on infrastructure include increases in flooding of roadways, rail lines, subterranean tunnels, and runways; increases in scouring of pipeline roadbeds and damage to pipelines; and increases in road washout, damages to rail-bed support structures, and landslides and mudslides that damage roadways and tracks.
Increases in Hurricane Intensity. It is likely (greater than 66% probability of occurrence) that tropical storm intensities, with larger peak wind speeds and more intense precipitation, will increase. Impacts of increased storm intensity include more frequent and potentially more extensive emergency evacuations; and more debris on roads and rail lines, interrupting travel and shipping. Impacts on infrastructure include a greater probability of infrastructure failures, increased threat to stability of bridge decks, and harbor infrastructure damage due to waves and storm surges.
Transportation infrastructures have long lifetimes. For roadways it is typically 25 years, railroads 50 years, and bridges and underpasses 100 years.
There are methods of laying railroad track that raise the temperature at which it will buckle, some pavement options are more resistant to rutting during hot weather than others and larger culverts can be placed under railroads and highways to accommodate heavier precipitation.
Thomas J. Barrett, Vice Admiral, Deputy Secretary, Department of Transportation
We have focused our approach on improving vehicle efficiency, increasing use of alternative fuels, reducing congestion, advancing the efficiency of the transportation system, and improving our understanding of the impacts of climate change on transportation networks.
Texas Transportation Institute estimated highway congestion in the United States wastes 2.9 billion gallons of fuel annually, translating to 2.6 million metric tons of unnecessary CO2.
In April, Secretary Peters announced a proposal that would establish the first new fuel economy standards for passenger cars in more than two decades, and would update and expand fuel economy standards for light trucks.
Through the Federal Highway Administration’s Congestion Mitigation and Air Quality Improvement Program (CMAQ), the Department is working with State and local governments on a range of programs to improve urban air quality within the transportation sector. For example, DOT has cooperated with the Environmental Protection Agency’s SmartWay Program initiative to retrofit trucks and truck stops with on-board and off-board auxiliary power to run vehicle lights and air conditioning and reduce truck idling. This program has reduced fuel consumption, criteria pollutant emissions, and greenhouse gas emissions, and has expanded to include idling emissions from marine, agricultural, rail, and off-road heavy-duty engines. The Federal Transit Administration funds the development and deployment of alternative fuel buses, including hydrogen fuel cell buses, and diesel-electric hybrid buses, as well as alternative fuels infrastructure for transit systems across the United States.
Early this year, DOT released The Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study, Phase I. This study provides an assessment of the vulnerabilities using 21 simulation models and a range of future scenarios.
The study found that potential changes in climate, through both sea level rise and subsidence over the next 50–100 years, could disrupt transportation services in several key ways.
- 27% of major roads
- 9% of rail lines
- 72% of area ports
All of these are at, or below 4 feet in elevation above sea level, and could be vulnerable to future sea-level rise combined with non-climate related sinking of the area’s land mass that is occurring in the area. The study is designed to help State and local officials as they develop their transportation plans and make investment decisions. Subsequent phases of the study are intended to focus on risks and adaptation strategies involved in planning, investment, and design decisions for infrastructure in the Gulf Coast region and nationwide.
The study was performed in partnership with the U.S. Geological Survey and State and local researchers, and is one of 21 ‘‘synthesis and assessment’’ reports produced as part of the U.S. Climate Change Science Program. A similar study that will soon be released is The Potential Impacts of Global Sea Level Rise on Transportation Infrastructure. This study was designed to produce rough estimates of how future climate change, specifically sea level rise and storm surge, could affect transportation infrastructure on the East Coast of the United States. Like the Gulf Coast Study, this study’s major purpose is to aid policymakers by providing estimates of these effects as they relate to roads, rails, airports, and ports.
Admiral BARRETT. Demand has gone up dramatically over the past several years globally. We’re getting up to the limits of what the available supply is, and we need to think very seriously about expanding that supply, particularly domestically, as you mentioned, in areas such as offshore or areas such as ANWR. We need to think very seriously about that, and improve our supplies.
Certainly, freight rail is a hugely efficient way of moving freight. It’s near capacity across the country. [As far as high-speed rail] the technology is enormously expensive. Unlike some other places, we’re using existing infrastructure. It takes a lot of work, and would probably be feasible only in very heavily trafficked corridors.
Senator KERRY. Let me ask you what is the guiding operative management target under which Department of Transportation, Department of Energy, and others are proceeding with respect to global climate change? This hearing is obviously on global climate change. This is the 20-year anniversary of Jim Hansen coming up here and telling us that it’s happening now, 20 years ago. Now we know it’s happening, even to a greater degree and faster than was predicted. I’d like to know what the operative estimate is of your Department as to where a potential, sort of, catastrophic tipping point may be, and how fast you have to respond to these infrastructure challenges. And I do that particularly in light of the fact that there are predictions, for instance, that—just last week, The Washington Post ran a story headlined, ‘‘Extreme Weather to Increase with Climate Change,’’ and, ‘‘Our scientists now agree that the droughts are going to get drier, the storms are going to get stormier, the floods are going to get deeper with climate change.’’ That’s a quote. They warn of more flooding, like we’re seeing in Iowa today, more heavy downpours, more droughts. ‘‘In March, the Department of Transportation found that the Gulf Coast would put a substantial portion of the region’s transportation infrastructure at risk. Storm surges in the Gulf Coast will flood more than half the area’s major highways, almost half of the rail miles, 29 airports, and virtually all of the ports.’’ So, given these predictions, which keep coming at us, under what time-frame do you believe you’re operating, in terms of the infrastructure expenditures necessary to respond to these threats?
Admiral BARRETT. The Gulf Coast study is regionally focused, where obviously, you’ve got the potential for sea level rise, temperature changes, storm intensity, and so on. With respect to transportation infrastructure, the first step is understanding the potential implications in local areas, because they vary. The next study will be the East Coast, where the impacts will be different. So, I think the first thing we are trying to do is understand better, particularly regionally, what the actual implications might be so that people who repair and renew and expand transportation infrastructure, which, to a large extent, rests in the states, as well as the Federal Government, can adjust to that over time as they repair and renew and build out.
I think there is no timeline, but we clearly need to understand what needs to be done, and, as we plan new projects. I think you will see adjustments to how we design, build, and install bridges to withstand climate better, and the impacts of climate change, whether it’s increased storms or higher river levels.
Senator KERRY. I’ll just say there really is a specific time. Jim Hansen, who is hugely respected, first warned of this, 20 years ago, and we’ve been slow to respond to it. The science is only coming back stronger and more rapidly and greater. Jim Hansen has now revised—right now, today, in these days—is warning us that we have less cushion than the scientists thought when they revised the cushion from several years ago. So, it’s gone from 550 parts per million of greenhouse gases, to 450, and now, they believe, less than that. There is a time-frame here. They’ve said we’ve got 10 years to get this right. And if you’re saying to us there’s no time- frame, the attitude of where we are, I think this is going to be very difficult to get done. And I think it’s, frankly, inappropriate, that that is where a major department, the Department of Transportation, stands today. I think there ought to be vast commitments in incentives, tax incentives, grants, expenditures to put America on a course to deal with this.
Senator STEVENS. I was told that the application of cap-and-trade, the credits that would be required during the construction phase alone for a pipeline would be the largest project in the history of the United States financed by private capital—that, for all the trucks and everything else that are going to be used in this construction phase over a period of 5–6 years, that the costs would be increased by at least 20% if they had to go out and buy credits under that concept for the pollution that’s taking place, notwithstanding the fact that the completion of the line would bring about the delivery of an enormous amount of new additional natural gas, which is not as polluting as the coal that people are using in many of the areas that would be supplied. There doesn’t seem to be any leeway for those who want to move to try and get a more efficient type of energy available. I think that cap-and-trade legislation would kill that pipeline.
Admiral BARRETT. I agree, in general. Cap-and-trade in transportation is very treacherous and needs to be looked at very closely.
Senator Ted Stevens, Alaska. The University of Alaska recently released a report on potential impacts of climate change on transportation and public infrastructure in Alaska. The report found that the effects of climate change stand to increase maintenance and replacement costs of public infrastructure in Alaska by up to 20%, or an additional $6 billion over the next two decades.
Conservation measures and alternative energies need to be part of our long-term strategy, but the idea that we can transition from fossil fuels anytime in the next 20 years is not realistic. Worldwide oil demand is expected to increase to 116 million barrels a day by 2030. We do need to explore ways to ease our dependence on fossil fuels in the transportation sector, but the investments required to make this transition are enormous. This is why I continue to argue that revenues from new domestic sources of oil, including ANWR, should be devoted to climate change adaptation and alternative energy development to reduce our dependence on foreign oil.
Senator Thomas R. Carper, Delaware. When I was Governor of Delaware, if we wanted to build a road or a highway or a bridge, the Federal Government paid for 80% of it. If we wanted to do a transit investment, the Federal Government provided 50% of it. If we wanted to invest in intercity passenger rail, the Federal Government provided nothing. And I’m sure we made investment decisions, that were probably wrong decisions, because of the difference in those modes of—or measures of Federal support.
Senator Bill Nelson, Florida. So you all are saying, with climate change, roads will buckle, bridges will wash out, railroads will be destroyed. If the seas rose 2 feet, in my state of Florida what kind of investment in transportation would be thrown out the window as a result of that?
Admiral BARRETT. I would guess substantial. But I would take the approach of quantifying specifically what rail would need to be rerouted, what roads would need to be readjusted. I think you need very specific analysis at a local and/or regional level. Understanding the specific impacts is enormously important.
Senator Bill Nelson, Florida. In a state like Florida, where 80% of the population is on the coast, it’s very difficult to go in and redo all of that infrastructure. And the cost is just going to be enormous. So, we’d better start figuring out something to do so that the seas don’t rise.
Senator John Thune, South Dakota. On account of aging and outdated infrastructure, we have economic challenges that are real, tangible, and identifiable today. Many of these infrastructure challenges are going unmet. Based on projections of population growth and government funding streams such as the Federal Highway trust, fund we know that these challenges will only grow in the future and resources will increasingly fall short of meeting these real short- and mid-term challenges.
Senator Frank R. Lautenberg, New Jersey. One-third of America’s greenhouse gas emissions comes from cars, trucks, and buses. And Dr. James Hansen, NASA scientist, said, just last week, ‘‘If we don’t begin to reduce greenhouse gas emissions in the next several years, then we are in trouble.’’ And we’ve got to begin by getting cars off the road, more people onto passenger rail, buses, subways, and other types of mass transit. Already, more and more people are riding public transit, and it’s more efficient, more convenient.
We’ve also got to act to ensure more efficient movement of freight. Trains are at least 6 times more energy efficient than trucks, and barges are more than 8 times as efficient. I chaired a Subcommittee hearing a couple of weeks ago on freight transportation needs, and, based on what I learned, I plan to introduce tax relief legislation which will encourage greater use of ships and barges, or, as we call it, short sea shipping between U.S. ports. By investing in fuel efficiency, mass transit, and better freight strategies, we can both bring relief to the people at the pump and fight global warming for generations to come.
John Porcari, Secretary, Maryland Dept. of Transportation; Chair, Climate Change Technical Assistance program advisory board; Chair, Standing committee on Aviation, American Association of State Highway & Transportation officials
The effort to reduce greenhouse gas emissions will involve many separate initiatives. There is no silver bullet. We should not get so caught up in debates about competing approaches that we lose sight of this bigger picture. In the transportation sector, this means we need improvements in fuel economy; we need greater usage of low-carbon fuels; we need better management of our transportation system to reduce congestion and smooth traffic flows; and we need to take steps that reduce the growth in vehicle miles traveled (VMT).
We need major technological breakthroughs in order to have any chance of dramatically cutting global emissions of greenhouse gases. For transportation, this means not only improvement in fuel economy, but ultimately a transition to entirely new fuels and new propulsion systems—for example, plug-in hybrid vehicles, zero-emission fuel-cells.
Between now and 2030, the U.S. Government forecasts that fuel efficiency will continue to improve and renewable fuels will gain market share, but also vehicle miles traveled (VMT) will continue to grow at 1.6 to 1.9 percent annually, outpacing the gains in fuel efficiency.
While technological change is essential to reducing greenhouse gas emissions, there is also a role for strategies that help to limit the growth in travel demand. As discussed above, the total VMT has grown much faster than population growth for the past several decades, but appears to have slowed considerably in the past few years. The average annual increase in VMT between 1990 and 2005 was approximately 2.2 percent. By contrast, population increased only about 0.8 percent per year during this period. Between 2005 and 2007, VMT growth occurred at a much slower rate—approximately 0.5 percent annually. Recent reports indicate that over the 12 month period between March 2007 and March 2008, VMT declined by 4.3 percent
There are many factors that can affect the future growth rate of VMT. Among the most important factors are economic trends
Against the backdrop of these larger trends, government policies also can play a role—albeit a limited one—in influencing VMT growth. Strategies that can be used include: (1) increasing investments in transit and intercity passenger rail, (2) expanding other alternatives to single-occupant vehicle travel, and (3) encouraging land uses that minimize the number and length of auto trips. Expanding Transit Service and Intercity Passenger Rail Transit service provides an alternative to automobile travel. The challenge is how to make the most of transit’s potential, given that it serves a relatively small share of travel in the United States (1% of passenger miles traveled) and major transit system expansions require significant public sector funding.
Passenger travel also occurs by walking, biking, carpooling, vanpooling, and telecommuting [so we should try to shift single-occupant autos toward these methods]. Telecommuting is likely to be a highly cost-effective strategy.
Patterns Land use decisions play an important role in determining the demand for automobile travel. Existing land use patterns in many areas make automobile travel a necessity for most trips. Higher-density land use patterns, combined with increased availability of transit service, could help to reduce the demand for automobile travel without reducing mobility.
Traffic congestion contributes to greenhouse gas emissions because vehicle engines operate less efficiently—and therefore produce higher emissions per mile— when they are driven at low speeds in stop-and-go traffic. The optimal speed for motor vehicles with internal combustion engines is about 45 mph. [FOR CO2, as usual, fuel efficiency is left out]. At lower speeds, CO2 emissions per mile are several times higher than at 45 mph. At higher speeds, CO2 emissions per mile increase as well, but somewhat less sharply. If we can reduce the amount of fuel burned by vehicles stalled in traffic that is a gain. If we can improve the flow of traffic so fuel is burned at more optimal efficiency rates then that will also produce a gain.
The way motorists operate their vehicles affects greenhouse gas emissions. The March 2007 TRB report notes that: Recent EAP data suggests that a significant component of greenhouse gas emissions—as much as 22 percent—results from inefficient operation of motor vehicles. These inefficiencies could result from factors beyond the driver’s control, such as traffic congestion, and also could reflect a driver’s own behavior, such as high-speed driving, vehicle maintenance, and tire pressures. Driver education and other policies could help to promote more efficient vehicle operations
Operational and maintenance impacts of excessive heat. ‘‘Periods of excessive summer heat are likely to increase wildfires, threatening communities and infrastructure directly and bringing about road and rail closures in affected areas. Longer periods of extreme heat may compromise pavement integrity (e.g., softening asphalt and increasing rutting from traffic); cause deformation of rail lines and derailments or, at a minimum, speed restrictions; and cause thermal expansion of bridge joints, adversely affecting bridge operation and increasing maintenance costs.’’
Increased flooding of coastal roads and rail lines. ‘‘The most immediate impact of more intense precipitation will be increased flooding of coastal roads and rail lines. Expected sea level rise will aggravate the flooding because storm surges will build on a higher base, reaching farther inland. . . . [The IPCC] identifies coastal flooding from expected sea level rise and storm surge, especially along the Gulf and Atlantic coasts, as one of the most serious effects of climate change. Indeed, several studies of sea-level rise project that transportation infrastructure in some coastal areas along the Gulf of Mexico and the Atlantic will be permanently inundated sometime in the next century.’’
- Disruption of coastal waterway systems. ‘‘[A] combination of sea level rise and storm surge could eliminate waterway systems entirely. For example, the Gulf Coast portion of the intercoastal waterway will likely disappear with continued land subsidence and disappearance of barrier islands. This will bring an end to coastal barge traffic, which helps offset rail and highway congestion; all ships will have to navigate the open seas.’’
- Impacts on Alaskan infrastructure. ‘‘The effects of temperature warming are already being experienced in Alaska in the form of continued retreat of permafrost, creating land subsidence issues for some sections of the road and rail systems and for some of the elevated supports for above-ground sections of the Trans-Alaska pipeline. Warming winter temperatures have also shortened the season for ice roads that provide vital access to communities and industrial activities in remote areas.’’
Several other studies have also concluded that climate change is likely to have widespread and severe impacts on transportation infrastructure.
U.S. DOT Gulf Coast Study. The study recognized ‘‘4 key climate drivers’’ in the Gulf Coast region: rising temperatures, changing precipitation patterns, rising sea levels, and increasing storm intensity. It suggested a range of possible responses, including raising transportation facilities in low-lying areas; hardening them to withstand storm events; relocating them to areas that are less vulnerable; and expanding redundant systems where needed.
ICF Studies of Sea-Level Rise. This two-part study focused specifically on the potential impacts of sea-level rise (not climate change in general) on transportation infrastructure. Phase 1 assessed impacts of sea-level rise on the District of Columbia, Maryland, Virginia, and North Carolina. Phase 2, which is still under way, will evaluate impacts of sea-level rise on seven additional States on the East Coast: New York, New Jersey, Pennsylvania, Delaware, South Carolina, Georgia, and the Atlantic Coast of Florida.
Edward Dickey, Ph.D. Affiliate professor of economics, Loyola College in Maryland; member, committee on climate change & U.S. transportation, transportation research board, division on earth and life studies, National Research Council, The National Academies
The past several decades of historical regional climate patterns commonly used by transportation planners to guide their operations and investments may no longer be a reliable guide for future plans. Future climate will include new classes (in terms of magnitude and frequency) of weather and climate extremes, such as record rainfall and record heat waves, not experienced in modern times as human-induced changes are superimposed on the natural variability of the climate. Decisions transportation professionals take today, particularly those related to the redesign and retrofitting of existing transportation infrastructure or the location and design of new infrastructure, will affect how well the system adapts to climate change far into the future.
Potentially, the greatest impact of climate change on North America’s transportation system will be flooding of coastal roads, railways, transit systems, and runways because of a global rise in sea level coupled with storm surge and exacerbated in some locations by land subsidence. The vulnerability of transportation infrastructure to climate change, however, will extend well beyond coastal areas. Therefore, Federal, state, and local governments, in collaboration with owners and operators of infrastructure such as ports and airports, and private railroad and pipeline companies should inventory critical transportation infrastructure to identify whether, when, and where projected climate changes in particular regions might be consequential.
Public authorities and officials at various governmental levels and executives of private companies are making short- and long-term investment decisions every day and should incorporate climate change into their long-term capital improvement plans, facility designs, maintenance practices, operations, and emergency response plans.
The significant costs of redesigning and retrofitting transportation infrastructure to adapt to the potential impacts of climate change suggest the need for more strategic, risk-based approaches to investment decisions. Transportation planners and engineers should incorporate more probabilistic investment analyses and design approaches that apply techniques for trading off the costs of making the infrastructure more robust against the economic costs of failure and should communicate these trade-offs to policymakers who make investment decisions and authorize funding.
David Friedman, Research Director & Senior Engineer, the Union of Concerned Scientists
Most of the planes, trains, ships, and automobiles we rely on were designed during the days of cheap oil when fuel efficiency was not a priority. Manufacturers have been slow to respond to recent consumer demands for fuel economy and consumers have also been slow to change. Both personal travel and goods movement have evolved around our extensive and dispersed national highway system. Compact, walk-able or bike-able communities and easy access to transit are the exception rather than the rule. Consumers and corporations lack choices to substitute for reliance on our cars and trucks. The transportation sector is almost exclusively reliant on fossil fuels, …alternative fuels meet only about 0.2 percent of U.S. transportation fuel
To reduce America’s oil addiction, and save consumers tens of billions of dollars, we must give consumers and corporations new options to use fuel more efficiently when they travel or ship goods. This can be achieved either through vehicle global warming pollution standards or by setting fuel economy standards. Through the Ten in Ten Fuel Economy Act, this Committee led the Nation forward on fuel economy for cars and light trucks for the first time in more than three decades. And for the first time ever, the door was opened to fuel economy standards for medium and heavy duty trucks thanks to this Committee. [off limits even more than autos??]
The projected benefits of just the light-duty portion of the Ten in Ten Fuel Economy Act highlight the importance of keeping efficiency a top priority. Meeting the minimum fuel economy requirement of 35 miles per gallon would cut global warming pollution for new cars and trucks nearly 30% by 2020. The minimum will also reduce oil consumption by nearly 9 billion barrels through 2030, rising to about 30 billion barrels saved through 2050. And finally, boosting fuel economy from today’s 25 mpg average to 35 mpg will save consumers the equivalent of reducing the price of today’s $4 per gallon gasoline by more than one dollar.
Delivery trucks and 18-wheelers could increase fuel economy from today’s level of less than 7 mpg for new vehicles to 10–11.5 mpg by 2030. This represents a boost of 50–70% while maintaining or expanding today’s hauling capacity. However, because of language in Ten in Ten, it may be at least 8 years before this committee’s medium and heavy duty standards are put to work.
NHTSA appears unwilling or unable to move the country on this path and this Committee should exercise its oversight authority to ask NHTSA to fix a variety of flaws used in setting their proposed standards [see document for links to recommendations]. Changes along these lines would redirect NHTSA’s efforts to the intent, not just the letter, of the law passed as part of Ten in Ten. NHTSA’s own analysis confirms that simply switching to total benefits, even with their poor gas price assumptions, would have led them to propose a fleet-wide average of at least 35 mpg by 2015— 5 years earlier than the required minimum. More realistic gas prices, even only setting the standard based on the marginal benefits, would also have led NHTSA to propose a fleet-wide average over about 35 mpg by 2015. Making matters worse, not only will NHTSA’s poor analysis shortchange consumers and lead to lower global warming pollution reductions, we can expect a similar approach to shortchange trucking companies and the environment when NHTSA address fuel economy standards for medium and heavy duty vehicles. This Committee’s oversight role is essential to avoiding this outcome.
While great strides can be made to improve vehicle efficiency, it is unlikely that technology alone will be able to keep pace with growing demand for personal and freight travel if we continue on our current path. As a result, despite the potential for parts of the transportation sector to increase efficiency by 50 percent or 100 percent, global warming pollution from transportation will continue to increase beyond current levels.
As with efficiency, the first step is to ensure that consumers and corporations have alternatives other than business as usual. Both urban and suburban areas need greater access to public transportation. As of 2001, less than one-third of the U.S. population lived within about a block of a bus line, while only about 40 percent lived within a half mile. The situation is even worse for rail, where only about 10% of U.S. population lived within a mile of a rail stop, while only about a quarter lived within 5 miles. In addition to transit, consumers need improved access to high occupancy vehicle (HOV) lanes, bike lanes, and more affordable housing near where they work. Corporations need many of the same things. While 18-wheelers provide a lot of flexibility in the freight world, it takes 5–7 times more energy to ship a ton of goods on a truck than on rail. Trucks and buses might also benefit from their own dedicated lanes where they are not caught up in as much stop and go traffic, making highways safer as well.
For these various new options to work, two key resources are needed: the money to fund them and the willingness to use them. Thankfully, in many cases, a system that makes sure people and products carry the full cost of their travel can help with both. Whether it is insurance, wear and tear on highways and bridges, or the costs of the pollution produced from tailpipes, charging per mile rather than per year or per gallon can create both a revenue stream for the needed investments and a more direct incentive to try out the newly available approaches. Some examples of these approaches include:
- Pay as you drive insurance: If you drive less, you are less likely to get into an accident. Paying for insurance by the mile rather than just by the car would both provide a more equitable distribution of insurance payments and encourage people to drive less.
- Per mile road user fees: Current highway construction and maintenance costs, and some transit costs, are covered by per gallon fuel taxes. Because fuel efficiency must go up, projected tax receipts will go down compared to a business as usual scenario. Per mile road user fees, adjusted to vehicle weight, could maintain a steadily growing revenue stream to keep our roads and bridges from falling apart while encouraging consumers and corporations to seek less expensive alternatives.
- Per mile pollution or congestion fees: Accidents and wear and tear are not the only costs associated with every mile we drive. Per mile pollution and congestion fees can become steady funding sources to hold people responsible for the damage they create while creating a funding stream for alternatives, plus they would provide another incentive to drive less. Per mile pollution and congestion fees tied to air travel and freight could be great ways to finance high-speed rail or simply much needed reinvestment into the country’s conventional rail infrastructure.
- Location efficient mortgages: Current tax codes give consumers the same break on their mortgage interest no matter where they live. While these tax breaks have helped many live out the American dream of owning a house, they have also helped lower the cost of owning homes that are farther from where people work, increasing daily travel. Revamping that tax code to provide greater tax breaks for those who live closer to work or transit will still help people realize a part of the American dream while ensuring it does not become a nightmare of pollution and congestion. This is not intended to be an exhaustive list, but instead points the way to policies and practices that could help cut projected personal travel by 25 to 35% percent by 2050 (15 to 20% by 2030) and could contribute to reducing the amount of freight that is trucked by 20% or more by 2050.
- Even more innovative approaches, such as reserving downtown areas for walking, biking, and public transit, or directly integrating our personal and freight vehicles with a mass transit system, could be part of a smart growth revolution that allows us to rethink how we move people and goods.
If we combine all of the approaches above for our light-duty cars and trucks, then by 2050 we will still need to supply the equivalent of 80 to 110 billion gallons of gasoline with 70–80% less global warming pollution than today’s fuel. For medium and heavy duty trucks, we will need the equivalent of another 30 to 40 billion gallons of gasoline with 75–80% less global warming pollution. And for the remainder of the transportation sectors, we will need yet another 40 to 50 billion gallons of low carbon fuel. That means, by 2050, we will need the equivalent of 150 to 200 billion gallons of gasoline with as much as an 80% reduction in global warming pollution compared to today’s gasoline.
Biofuels will play an important part in a low carbon future, it is unlikely, at best, that we can sustainably produce sufficient low-carbon biofuel in the U.S. A more realistic estimate of sustainable biofuel potential, one that minimizes tradeoffs between food and fuel and does not encourage deforestation in other countries, would be closer to 40 to 50 billion gallons, unless breakthroughs are achieved in novel biomass resources. To supply the rest of transportation’s needed energy, we must to tap into renewable electricity and clean hydrogen. But these resources will not appear overnight, nor will the vehicles that must be sold to use these low-carbon fuels. We will need multiple policies to bring about the needed fuel revolution.
The U.S. needs to move away from a piecemeal approach to transportation energy and environmental policy and instead adopt a comprehensive set of policies that will tap into both the near term and long term solutions that are available or on the drawing boards. This will require a longer term perspective and a combination of consistent, significant, and sustained policies. Yes, we do need to rethink our transportation system, but in doing so, we will not only dramatically lower global warming pollution, we will save consumers billions, create new jobs in America and ultimately cut our addiction to oil.
Edward R. Hamberger, President & CEO, Association of American Railroads
Moving more freight by rail would also help reduce highway congestion, which costs $78 billion just in wasted travel time (4.2 billion hours) and wasted fuel (2.9 billion gallons) each year, according to the Texas Transportation Institute’s 2007 Urban Mobility Report. (The total costs of congestion are far higher if lost productivity, costs associated with cargo delays, and other items are included.) A typical train, though, takes the freight equivalent of several hundred trucks off our congested highways, thus enhancing mobility and reducing the amount of greenhouse gases emitted by motor vehicles stuck or slowed in traffic. Railroads also reduce the costs of maintaining existing roads and reduce the pressure to build costly new roads, freeing up limited funds for other purposes.
Train handling. In part, railroad fuel efficiency depends on how well an engineer handles a train. That’s why railroads use the skills of their engineers to save fuel. For example, many railroads offer training programs through which engineers and simulators provide fuel-saving tips. On some major railroads, the fuel consumption performance of participating engineers is compared, with awards given to the top ‘‘fuel masters.’’ In addition, railroads are using sophisticated on-board monitoring systems to gather and evaluate information on location, topography, track curvature, train length and weight, and more to provide engineers with real-time ‘‘coaching’’ on the best speed for that train from a fuel-savings standpoint.
Information technology. Many railroads use advanced computer software to improve their fuel efficiency. For example, sophisticated modeling tools identify the best way to sequence cars in a large classification yard. Railroads also use innovative ‘‘trip planning’’ systems that automatically analyze crew and locomotive availability, track congestion, the priority of different freight cars, track conditions, and other variables to optimize how and when freight cars are assembled to form trains and when those trains depart. The result is smoother traffic flow, better asset utilization, and reduced fuel use.
Idle reduction technology. Locomotives often have to idle when not in use to pre vent freezing, provide for crew comfort, or for other reasons. However, many railroads have installed idle-reduction technology that allows main engines to shut down under certain conditions. One advantage of genset locomotives is that their smaller engines use antifreeze, allowing them to shut down in cold weather. Railroads also use ‘‘auxiliary power units’’ to warm engines so that locomotives can be shut down in cold weather.
Components, maintenance, and design. Railroads use innovative freight car and locomotive components, maintenance programs, and designs to save fuel. For example, advanced lubrication techniques save fuel by reducing friction; the use of low torque bearings on freight cars and improving the aerodynamic profile of trains save fuel by reducing drag; and the use of ‘‘distributed power’’ (locomotives placed in the middle of trains) can, in certain applications, save fuel by improving operational efficiency.
Amtrak’s locomotive fleet is antiquated: its diesel switcher locomotive fleet is 40 years old; the average age of the AEM–7 electric fleet is 25 years, and its overhead electric catenary system in the Northeast Corridor is 1930s technology that does not allow Amtrak to take advantage of the improved efficiency of modern converter, transformer, and transmission designs. Passenger cars could be made lighter and more aerodynamic. These are all areas worthy of government investment that will pay huge dividends over the long term. Moreover, the implementation of high-speed rail corridors, if done in ways that minimize the substantial operational, engineering, legal, and other impediments that often hinder the ability of freight railroads to accommodate passenger trains, would go a long way in providing a realistic alternative to short-distance air travel and driving for millions of trips per year while significantly reducing the carbon footprint associated with that travel.
Senator LAUTENBERG. Even with fuel efficiency improvements, airplanes will not be as efficient as trains, particularly for journeys of 400 miles or less, and particularly in highly populated areas. Doesn’t it make sense, environmentally as well as economically, to invest more in rail? Shouldn’t we be encouraging the most efficient travel possible? And as it appears now, it’s rail.
Senator Barbara Boxer, California. Six of the Nation’s top ten freight gateways, which are centers for economic activity, will be at risk if sea levels rise. 60,000 miles of coastal highways already experience coastal storm flooding and wave action. This number is certain to increase with rising the sea levels, leaving communities vulnerable to ocean waves and cutting off evacuation routes.
ASSOCIATION OF AMERICAN RAILROADS
AAR subscribes to the following 11 Federal funding principles, which fall into three categories. The first 9 principles assure that Federal funding will create sustainable partnerships with public entities while maximizing the public benefits found in rail projects. The tenth promotes freight rail as a solution to looming transportation challenges. The eleventh clarifies that grade separations do little to benefit rail capacity or rail productivity.
- Federal funding and policies must not reduce and should encourage private investment in the Nation’s rail system.
- In all public-private partnerships, public benefits should be funded by public funds, and railroad benefits should be funded by railroad funds.
- The same funding principles should apply to projects involving other modes of freight transportation.
- If the Federal Government establishes a freight fund to fund public benefits of freight rail projects, funding should not be extracted from freight transportation providers or their customers or disadvantage the economics of rail transportation. Further, freight railroads should not be required to assess or collect any fees. The rail logistics system should not be saddled with increased costs to fund public benefits, either directly or through a freight fund.
- Federal fees associated with a freight fund should preempt state and local fees, unless there is mutual agreement among the parties.
- Any involvement by a rail carrier in public-private projects must be strictly voluntary.
- Federal funding of public benefits must not be in lieu of the enactment of Federal investment tax incentives for increased private investment.
- Federal funding must not be conditioned upon a change in the present economic regulation of the rail industry or other industry concessions.
- Federal funding must be executed in a manner that preserves the rail industry’s current ownership rights.
- Federal freight investment should focus on key transportation projects with significant public benefits, such as eliminating rail chokepoints, improving service to shippers, facilitating international trade, reducing greenhouse gas emissions, cutting vehicle miles traveled, and improving safety. Such projects should be selected based upon standardized, agreed-upon methodology.
- Grade separations must continue to be regarded as primarily beneficial to the highway/road user. They do little to increase freight rail capacity or improve rail productivity.
Comprehensive, reliable, and cost-effective rail service is critical to our nation, and that, in turn requires having adequate rail capacity. Railroads must be able to both maintain their extensive existing infrastructure and equipment and build the substantial new capacity that will be needed to meet much higher future freight and passenger transport demand. Our privately-owned freight railroads are working hard every day to help make sure America has the rail capacity it needs. They’re re-investing record amounts in their systems ($420 billion from 1980 to 2007, or more than 40 cents out of every revenue dollar), adopting innovative new technologies and operating plans, and forging partnerships with each other, other transportation providers, and customers. Policymakers can help ensure that more freight and passengers move by rail by addressing a number of serious impediments to meeting the rail capacity challenge.
Local Opposition to Rail Projects. Under existing law, state and local regulations (other than local health and safety regulations) that unreasonably interfere with rail operations are preempted by Federal regulations. These Federal regulations protect the public interest while recognizing that our railroads form an integrated, national network that requires a uniform basic set of rules to operate effectively. Nevertheless, rail expansion projects often face vocal, sophisticated opposition by members of affected local communities. In many cases, railroads thus face a classic ‘‘not-in-my-backyard’’ problem—even for projects for which the benefits to a locality or region far outweigh the drawbacks. In the face of local opposition, railroads try to work with the local community to find a mutually-satisfactory arrangement, and these efforts are usually successful. When agreement is not reached, however, projects can face seemingly interminable delays and sharply higher costs. Often, local communities allege violations of environmental requirements to challenge a proposed project, even though detailed environmental reviews, when required, already identify the impacts of rail projects and determine necessary mitigation measures. Railroads understand the goals of environmental laws and appreciate the need to be responsive to community concerns, but community opposition to rail operations can be a significant obstacle to railroad infrastructure investments, even when the opposition has no legal basis. Policymakers can help by taking steps to shorten the time it takes for reviews of rail expansion projects in ways that do not adversely affect the quality of those reviews.
If rail capacity needs are not properly addressed, by 2035 some 16,000 miles of primary rail mileage—nearly one-third of the 52,000 miles covered in the study—will be so congested that a widespread service breakdown environment would exist. (Today, less than 1% of rail miles are that congested.) Because our rail system is interconnected, this outcome would mean that America’s entire rail system would, in effect, be disabled.
One way to help bridge the funding gap is through tax incentives for rail infrastructure investments.
The 2007 1125/H.R. 2116 (the ‘‘Freight Rail Infrastructure Capacity Expansion Act of 2007) calls for a 25% tax credit for investments in new track, intermodal facilities, yards, and other freight rail infrastructure projects that expand rail capacity. All businesses that make capacity-enhancing rail investments, not just railroads, would be eligible for the credit. A rail ITC would addresses the central challenge of how to move more freight without causing more highway gridlock or environmental degradation. For a railroad considering whether to fund an expansion project, an ITC would reduce the cost of the project, raising the likelihood that the project will be economically viable. It would help worthwhile projects get built sooner, but would not be enough to cause economically-unjustified projects to go forward. An ITC would also stimulate the economy. U.S. Department of Commerce data indicate that every dollar of freight rail infrastructure investment that would be stimulated by a rail infrastructure ITC would generate more than three dollars in total economic output. Each $1 billion of new rail investment induced by the ITC would create an estimated 20,000 jobs nationwide. The benefits to our economy would be broad and long lasting. Policymakers should also support a short line tax credit. Since 1980, more than 380 new short lines have been created, preserving thousands of miles of track (much of it in rural areas) that may otherwise have been abandoned. In 2004, Congress enacted a 50% tax credit (‘‘Section 45G’’) for investments in short line track rehabilitation. The focus was on assisting short lines in handling the larger and heavier freight cars that are needed to provide their customers with the best possible rates and service. Since Section 45G was enacted, hundreds of short lines have rapidly increased the volume and rate of their track rehabilitation and improvement programs. Unfortunately, Section 45G expired in 2007. Pending legislation in Congress (S. 881/H.R. 1584, the ‘‘Short Line Railroad Investment Act of 2007’’) would extend this tax credit and thus preserve the huge benefits it delivers. Finally, a more pronounced use of public-private partnerships would help get more freight on our rails. Public-private partnerships reflect the fact that cooperation is more likely to result in timely, meaningful solutions to transportation problems than a go-it-alone approach. Without a partnership, projects that promise substantial public benefits (including reduced highway gridlock and highway construction and maintenance costs, reduced pollution and greenhouse gas emissions, and enhanced mobility) in addition to private benefits are likely to be delayed or never started at all because it would be too difficult for either side to justify the full investment needed to complete them. In contrast, if a public entity shows it is willing to devote public dollars to a project based upon the public benefits that will accrue, the private entity is much more likely to provide the private dollars (commensurate with private gains) necessary for the project to proceed. Partnerships are not ‘‘subsidies’’ to railroads. Rather, they acknowledge that private entities should pay for private benefits and public entities should pay for public benefits. In many cases, these partnerships only involve the public contributing a portion of the initial investment required to make an expansion project feasible, with the railroad responsible for keeping the infrastructure productive and in good repair.
JAMES M. TURNER, DEPUTY DIRECTOR, NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY, U.S. DEPARTMENT OF COMMERCE
Supporting Innovation in Advanced Materials—Lightweight Materials and Nanocomposites
Automobiles and light trucks consume 79% of all U.S. distilled fuel. Lightweight materials are a big part of the solution to reduce our consumption. The Department of Energy, Office of Vehicle Technologies states that lightweight materials are needed to ‘‘offset the increased weight and cost per unit of power of alternative powertrains (hybrids, fuel cells) with respect to conventional powertrains.’’
The cement and concrete industry is a large generator of greenhouse gas, mainly carbon dioxide (CO2), during the manufacturing production process. One U.S. ton of cement produces about one ton of CO2 and the annual world production of cement—2.5 billion tons—is equal to a 3–9% estimated share of world man-made CO2. In 2006, the U.S. produced 96 million tons of cement and 37 million tons were imported for use in the U.S. It is estimated that 1.5% of U.S. man-made CO2 generation comes from concrete production. And while this is a large number, cement production is forecast to greatly increase over the next 20–40 years because of burgeoning demand for new and replacement infrastructure.
In the U.S., the energy efficiency of cement production is already high, and is probably only capable of fairly small improvements. One is limited to reducing the CO2 that is given off from the raw materials by partially substituting another material for the cement in concrete, such as the substitution of non-CO2 containing materials for a portion of the limestone in the raw materials. Around the world, the two most common minerals used to substitute for cement are fly ash and granulated ground blast furnace slag. The use of fly ash and slag in concrete can actually improve the properties of concrete, especially the durability. Let me highlight some of NIST’s work to address the needs of the concrete industry itself. All of our work will improve our understanding of how cement and concrete actually work, and ultimately should make possible improvements in the formulation and use of cement that could save hundreds of millions of dollars in annual maintenance and repair costs for concrete structures and the country’s infrastructure. This work should also lead to improving the properties and performance of concrete while decreasing energy costs and reducing the CO2 emissions from its production.
Cement may be the world’s most widely used manufactured material—more than two billion metric tons are consumed each year—but it also is one of the more complex. And while it was known to the Romans, who used it to good effect in the Coliseum and Pantheon, questions still remain as to just how it works, in particular how it is structured at the nano- and microscale, and how this structure affects its performance.
NIST researchers are investigating adaptive concrete technologies including internal curing and the incorporation of phase change materials into concrete to increase its service life. Field concrete is exposed to a wide variety of environmental conditions and distress. These environmental factors often result in premature degradation and/or failure. Examples include early-age cracking due to shrinkage and degradation as a result of repeated cycles of freezing and thawing, and deterioration due to damaging reactions of chemicals (chloride, sulfate, and alkali ions, etc.).
NIST is working to have a dramatic effect on the concrete industry through doubling the service life of new concrete by altering the composition of concrete. One of the main goals of high performance concrete is to increase service life. Under most chemical erosion scenarios, the service life of concrete depends on its reaction to external chemicals entering it. There are a number of ways to significantly increase the service life of concrete including reducing the porosity and adding mixtures to provide increased resistance to the infiltration of chemicals. Unfortunately, one of the side effects of these modifications is a large increase in the propensity for early-age cracking, and the desired barrier performance of a dense concrete is easily compromised by the formation of just a few cracks.
The time until the steel reinforcement in the concrete rusts is related to the depth of concrete cover, so that if you increase the thickness of concrete over the steel by 50%, you get approximately double the expected service life. More concrete covering the rebar may not be feasible because of design constraints, and both additional concrete and changing the composition to resist chemicals can add considerable cost to construction.
James M. Turner, deputy director, National Institute of Standards & Technology, U.S. Department of Commerce on Hydrogen
Getting an Accurate Fill-Up. Working very closely with State weights and measures organizations, NIST has long maintained the standard for ensuring that consumers actually receive a gallon of gas every time they pay for one. Now NIST researchers are incorporating the properties of hydrogen in standards that will support the development of hydrogen as a fuel in vehicles. One of the challenges in the use of hydrogen as a vehicle fuel is the seemingly trivial matter of measuring fuel consumption. Consumers and industry are accustomed to high accuracy when purchasing gasoline. Refueling with hydrogen is a problem because there are currently no mechanisms to ensure accuracy at the pump. Hydrogen is dispensed at a very high pressure, at varying degrees of temperature and with mixtures of other gases. NIST’s research and new technological innovations will enable accuracy in hydrogen fill-ups.
Technical challenges need to be overcome to make hydrogen-powered vehicles more practical and economical. Fuel cells need to operate as reliably as today’s gasoline engine. We need systems that can store enough hydrogen fuel to give consumers a comfortable driving range. We need science-based standards that will guide local officials in establishing codes for building and fire safety as they relate to something like a hydrogen fueling station. And we need a technical infrastructure to ensure the equitable sale of hydrogen in the marketplace, as exists today for gasoline.
Transporting and Distributing Hydrogen. One barrier to hydrogen is pipelines. There are currently 700 miles of hydrogen pipelines in operation—that is in comparison to 1 million miles of natural gas pipelines. To move to a nationwide use of hydrogen, safe and effective pipelines have to be developed.
Tests have to be developed to test for the degradation that is likely to occur to the metals that can be caused by hydrogen weakening the pipeline. By establishing the unique test facilities and standard test
Hydrogen Storage. Hydrogen is promoted as a petroleum replacement that presents an attractive alternative for fueling automobiles and trucks. A major roadblock associated with the use of hydrogen is the inability to store it efficiently. Hydrogen’s properties have been shown to embrittle metals and current storage technologies limit the potential range of hydrogen powered vehicles.
To develop fuel cells for practical use, NIST researchers are developing measurement methods to characterize the nanoscale structure and dynamics of polymer membranes inside the fuel cell to enable stronger fuel cells.
THOMAS J. BARRETT, VICE ADMIRAL, DEPUTY SECRETARY, DEPARTMENT OF TRANSPORTATION
DOT has, and is, undertaking research required for development of safety standards for future hydrogen vehicles and infrastructure. Over the last 5 years, the Administration has invested about $1.2 billion in hydrogen research and development to help bring hydrogen fuel cell vehicles to market.
Aviation is a somewhat unheralded but real success story in these areas. Compared to the year 2000, U.S. commercial aviation in 2006 moved 12% more passengers and 22% more freight, while actually burning less fuel and reducing our carbon input by a million tons. This is a result of airframe, power, and air traffic system improvements. U.S. airlines, in a very competitive market, have committed to another 30% improvement by 2025, a goal the industry adopted before the recent spike in fuel prices. I would urge caution in not hamstringing this flagship U.S. industry that has such global reach by imposed new emission regimes.
Clearly, anyone who has flown lately, though, can attest to the fact that we are always mindful of the indispensable role that transportation plays in sustaining and improving our economy, and supporting our trade, and the importance of transportation infrastructure to the millions of Americans who depend on it for their mobility and the competitiveness of their businesses.
CCSP. 2008. Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study, Phase I. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research [Savonis, M.J., V.R. Burkett, and J.R. Potter (eds.)]. Department of Transportation, Washington, D.C., USA, 445 pp.
CCSP. 2008. Weather and Climate Extremes in a Changing Climate. Regions of Focus: North America, Hawaii, Caribbean, and U.S. Pacific Islands. A Report by the U.S. Climate Change Science Program and the Subcommittee on Global Change Research. Department of Commerce, NOAA’s National Climatic Data Center, Washington, D.C., USA, 164 pp.
Peterson, Thomas C., et al. 2008. Climate Variability and Change with Implications for Transportation, National Research Council, Washington, D.C., http://onlinepubs.trb.org/onlinepubs/sr/sr290Many.pdf, 90 pp.
NRC. 2008. The Potential Impacts of Climate Change on U.S. Transportation. National Research Council of the National Academy of Sciences, Transportation Research Board Special Report #290, National Research Council, Washington, DC, 218 pages.