Freight Digital Solutions and
Emerging Technologies
U.S. Department of Transportation, Climate Change Center
Climate Strategies that Work
Digital solutions and
innovative technologies
provide a seamless
experience for freight carriers
and consumers alike while
reducing traffic and emissions
associated with deliveries.
Overview
Did you know?
The National Renewable Energy Lab (NREL) has partnered with Google to
reduce emissions through more eco-friendly mapping in Google maps. Eco-
routing solutions have been shown to reduce fuel consumption and emissions
by 10-20% or more (NREL, 2021).
Best Suited for:
Long Term & Short Term
Urban, Suburban, Rural & Tribal
Freight digitalization can provide environmental, health, and
economic benefits, including reduced congestion on roadways
and in and around ports, lower emissions, and operational and
efficiency improvements for freight carriers (see the Freight
Operational Strategies strategy page for more detail). Digital
solutions include advanced scheduling and routing systems, location
tracking using geographic information systems (GIS), and other
intelligent transportation systems (ITS) (see the Intelligent
Transportation Systems strategy page for more detail). The
International Transport Forum analyzed the overall impacts of a
‘Digital Transformation’ scenario on freight-related CO₂ emissions
and found that implementing a range of digital solutions to the
freight sector will result in over 20% lower CO₂ emissions in 2050
compared to the no-action baseline.
Curb Management:
Managing the curb is an increasingly important task that can contribute to
VMT reductions from freight in both urban and downtown rural core
contexts. Curb management options, such as parking spot reservation
systems and off-peak deliveries, can be implemented using phone apps and
GIS location tracking. Delivery lockers can also reduce curb congestion and
respond to an increase in demand for deliveries. Firms can use delivery
lockers to consolidate shipments for multiple households, reducing delivery
costs and trips. At the same time, customers can pick up their package at
their convenience at a secure location close to their home. Both companies
and consumers can manage delivery lockers using apps and automated
systems.
Examples of freight digitalization
technologies include:
- Apps that freight carriers, businesses, and consumers can
use to manage goods movement and deliveries. - Advanced truck routing systems (dynamic re-routing or
eco-routing). - Electronic delivery lockers.
- Micromobility deliveries, including e-cargo bikes and
robots. - Drone deliveries.
- Ports technologies.
- Multi-modal scheduling systems.
- Truck appointment systems.
- Just-in-time queuing.
- Automatic gates.
- Vehicle-to-everything (V2X) deployments for freight.
- Connected vehicle technologies.
- V2X-enabled vehicles using dedicated 5.9 GHz
spectrum.
- V2X-enabled vehicles using dedicated 5.9 GHz
- Signalized intersections.
- Connected vehicle technologies.
The impact of digital transformation on freight-related CO₂ emissions.
The total rise in emissions between 2019 and 2050 is limited to only
18%, despite the expected 165% increase in freight transport demand.
(Source: ITF, 2022)
Freight industry leaders have strong incentives to reduce unnecessary
travel, delays, and other factors that contribute to higher operating costs.
Innovative technologies, such as truck platooning technology or other
connected vehicle technologies, can improve the efficiency of
transportation assets and services, including freight logistics.
Real-time data can allow transportation systems to operate more efficiently
and respond to changes and unexpected delays more effectively. For
example, optimizing truck deliveries to ports through improved scheduling,
automated gate systems, and other strategies can reduce emissions from
trucks idling while waiting to unload their cargo. Micromobility devices such
as electric cargo bikes have increasingly become integrated into goods
movement and are typically managed using apps and location-based
services. Truck signal priority can be used at intersections with high levels of
truck traffic to extend the green time and allow more trucks to make it
through a signal cycle. Giving trucks extra green time can improve safety by
reducing the likelihood that a truck will run a red light and cause a crash. It
can also reduce delays and congestion caused by the longer acceleration
times that trucks need to reach posted speed limits.
Greenhouse GAs Reduction Potential
Frequent acceleration/deceleration, excessive speeds, slow movements on congested roads, and unnecessary idling contribute to increased fuel
consumption and emissions.
Eco-driving strategies, early warning systems, and other vehicle-to-vehicle and vehicle-to-infrastructure technologies (V2V/V2I) systems can
reduce CO₂ emissions. For example, hazard alert systems installed in trucks and passenger cars can reduce CO₂ emissions by around 5% for
vehicular densities up to 3000 vehicles/hour (Outay et al., 2019).
Advanced truck routing systems can reduce VMT and emissions. In one study with a medium-sized logistics company, application of an advanced
scheduling and routing system to urban deliveries resulted in a 27% reduction in CO₂ emissions and the same number of orders being delivered
with 8.6% less routes, 18% less service time, and 21% less kilometers per route (Kechagias et al., 2020).
The Pittsburgh Smart Loading Zones program uses a combination of technology to monitor loading zone utilization and notify the parking
authority of violations. Pilot program outcomes include substantial reductions in idling time and curb disruptions: decrease in average park duration
of 25%, decrease in average double park duration of 40%, and increase in turnover of nearly 25% (Engage Pittsburgh, 2024).
The North Central Texas Council of Governments is working with Freightpriority to deploy signal prioritization technology in the Dallas-Fort Worth
area. The truck signal priority system uses existing GPS data to provide extra green time as needed at specific intersections. The deployment is
expected to improve route efficiency and reduce fuel use and freight truck-related emissions across the region (Freightpriority, 2024).
vehicle-to-everything (V2X) Technologies and Freight-Related Emissions
Typical trucks that are not driving empty carry only about 57% of their capacity. “Digital freight brokers” can help consolidate loads from multiple
shippers onto a single trailer to improve the loader factor. Pooling shipments can reduce GHG emissions by 15-40% (Nakajima, 2024).
Flock Freight has developed an alternative to LTL called “shared truckloads” (STL). Their technology estimates shipment pricing based on the
probability that the shipments can be pooled and creates a shipment plan for a single truck that enables pooling when possible. Flock estimates
that their STL solution reduces GHG emissions by 15-40% due to more direct routing and improved load factors (Nakajima, 2024).
Empty truck trips are responsible for a significant share of VMT and emissions. Collaboration among carriers and truck appointment systems
(TASs) can help reduce the number of trips between terminals and client locations (Schulte et al., 2017).
Reducing Empty Truck Trips and Improving Load Factor
"Full Truckload" (FTL) and "Less-than-Truckload" (LTL) are types of trucking services. FTL is popular with business that move large
volumes of stock on a regular basis. One shipping trailer contracts to a single shipper, consignee or customer. The freight shipment (which
may or may not utilize the entire trailer) is carried from point A to point B. In LTL shipping, the carrier makes multiple stops to pick up and
drop off goods, and the shipment may be loaded and unloaded multiple times. LTL is better suited for occasional, smaller shipments where
delivery times can be flexible.
This section provides an overview of greenhouse gas (GHG) emission reductions associated with the strategy. It highlights key findings and relevant metrics
from GHG modeling resources, peer-reviewed studies, and real-world applications.
Co-benefits
Safety
Digital solutions have transformed the freight logistics industry. In a
2016 white paper, the World Economic Forum estimated that digital
technology will lead to the creation of 2 million jobs and reduce
carbon emissions by 10 million tons. Overall, the total value impact
to the logistics industry was estimated to be $1.5 trillion (WEF, 2016).
Economic Growth
Accessibility and Equity
Communities of color and low-income neighborhoods are
particularly disadvantaged with respect to freight-related
congestion, noise, and emissions (EPA, 2014). Digital solutions can
direct truck shipments along more equitable routes, shift freight
traffic from trucks to other modes, and reduce fuel burn and
emissions through use of ITS and V2V/V2I technologies. For example,
a StreetLight analysis found that truck activity has a
disproportionate impact on disadvantaged communities in New York
State in terms of travel time delays, with the average truck delays
about twice as long per roadway mile in disadvantaged vs. non-
disadvantaged census tracts (StreetLight, 2024).
Digital solutions can direct truck shipments along more equitable
routes, shift freight traffic from trucks to other modes, and reduce
fuel burn and emissions through use of ITS and V2V/V2I
technologies.
See the Intelligent Transportation Systems strategy page for more
detail.
Rural Communities
Cost Savings
Air Quality and Health
Digitalization of freight movements can improve safety
outcomes, including decreasing interactions between freight
vehicles and vulnerable road users. See the safety benefits of
recent ITS deployments here.
- Trucks can be retrofitted with bicyclist/pedestrian detection
systems and collision early-warning systems. - Signal priority for freight vehicles at intersections can reduce
frequent accelerations and decelerations and reduce the
likelihood of accidents. - Smart loading zones and curb management systems reduce
congestion from delivery vehicles and the need for double
parking and parking across bike lanes.
See the Intelligent Transportation Systems strategy page for
more detail.
The use of computer systems for vehicle routing and scheduling,
especially in cases where more than 10 vehicles are needed,
usually leads to cost reductions of between 10% and 20% for
carriers (Drexl, 2012).
Tire manufacturer Michelin designed EFFIFUEL, a freight logistics
ecosystem that includes telematics, training in eco-driving
techniques, and an optimized tire-management system. The
system can lead to an average annual savings of €3,200 ($3,542
USD, 2016) for long-haul trucks, or at least a 2.1% reduction in
total cost of ownership for truck fleet operators (WEF, 2016).
The United Parcel Service’s (UPS) Package Flow Technology
reduces fuel consumption and emissions by optimizing pickup
and delivery allocations and by designing delivery routes that
minimize total distance covered, driving time, and idling time.
The system also uses historical data to forecast conditions and
create routes that eliminate left turns to minimize waiting at
lights. In 2009, UPS reported savings of almost $200 per vehicle
per day in fuel costs due to a combination of these strategies
(UPS, 2009).
Large volumes of freight either originate in rural areas or are
transported through rural areas by road, rail, and waterways. Two-
thirds of rail freight originates in rural areas, and nearly half of all
truck VMT occur on rural roads (USDOT, 2023). Freight digitalization
can improve network efficiency and support the selection of less
carbon intensive modes to reduce the impacts of freight transport
on rural communities.
Diesel freight is responsible for significant amounts of particulate
matter pollution and adverse health effects, particularly in
communities living near highways and ports (EPA, 2014). Digital
solutions can support eco-routing and optimize freight movements
to minimize impacts to local air quality, e.g., by choosing freight
transport with less carbon-intensive modes. A study of geofencing-
enabled truck routing in Southern California showed a drop in NOx
emissions of 74% in disadvantaged communities when trucks used a
“least-emissions path” eco-routing option (Jaller et al., 2021).
This section outlines the multiple co-benefits associated with the strategy, including safety benefits, local air quality improvements, and improved
accessibility. Each co-benefit presents examples that demonstrate how the strategy enhances regional or community well-being while addressing
emissions.
For example, a curb management system in Washington, DC
reduced double parking by 64% and immediately improved
safety in crosswalks and bike lanes (Pyzyk, 2019).
Cost Considerations
The cost to implement freight digitalization systems varies widely depending on the scale, scope, and location of the project.
The ITS Joint Program Office maintains a list of System Cost Updates for V2X Deployments. Freight-related examples include:
- The Colorado Truck Parking Information Management System (TPIMS) has a total estimated capital cost of $9 million.
- An intelligent truck parking management system using cameras to detect parking availability and automatically notify drivers via a website, in-cab
messaging, and roadside dynamic message sign costs $70,000 to $120,000. - The cost to deploy a real-time truck parking information system was estimated at $391,000 per rest area.
See the Intelligent Transportation Systems strategy page for more detail.
Funding Opportunities
FHWA’s Saving Lives with Connectivity: Accelerating V2X
Deployment grant program will fund projects that advance connected
and interoperable vehicle technologies. Connected and interoperable
vehicle technologies have the potential to greatly reduce motor vehicle
crashes and resultant fatalities, injuries, and property damage.
USDOT’s Complete Streets AI Initiative is a $15 million multi-phase
effort that will fund small business to develop new decision-support
tool(s) for state, local, and tribal transportation agencies that focus on
Complete Streets.
FHWA’s Advanced Transportation and Innovative Mobility
Development (ATTIMD)/Advanced Transportation Technology and
Innovation (ATTAIN) support the deployment, installation, and
operation of advanced transportation technologies. Eligible activities
under this program that advance transportation system efficiency
include implementing technology to integration of transportation
service payment systems and implanting advanced mobility access and
on-demand transportation service technologies.
DOE’s Advanced Research Project Agency (ARPA-E) is funding
projects that develop technology to model the low-carbon intermodal
freight transportation system of the future. The projects are expected
to reduce emissions by enabling prioritization of low-carbon energy
infrastructure deployment, along with data required for the effective
deployment of this optimized distribution system.
USDOT’s Strengthening Mobility and Revolutionizing
Transportation (SMART) Grants Program provides grants to eligible
public sector agencies to conduct demonstration projects focused on
advanced smart community technologies and systems in order to
improve transportation efficiency and safety. Delivery/logistics is
included as a technology area for eligible projects.
FHWA’s Exploratory Advanced Research (EAR) Program is exploring
the development of artificial intelligence (AI) and machine learning
technology within the surface transportation sector. The EAR program
has also funded several computer vision research projects to enhance
the safety and efficiency of surface transportation.
USDOT’s Reduction of Truck Emissions at Port Facilities Grant
Program provides funding to reduce truck idling and emissions at
ports, including through the advancement of port electrification. The
program also includes a study to address how ports and intermodal
port transfer facilities would benefit from increased opportunities to
reduce emissions at ports, and how emerging technologies and
strategies can contribute to reduced emissions from idling trucks.
FHWA’s National Highway Freight Program (NHFP) is aimed at
improving the efficient movement of freight on the National Highway
Freight Network (NHFN). The program supports investment in
infrastructure and operational improvements that strengthen
economic competitiveness, reduce congestion, reduce the cost of
freight transportation, improve reliability, and increase productivity.
FHWA’s Accelerated Innovation Deployment Demonstration
Program provides funding to State departments of transportation
(DOTs), Federal land management agencies, and Tribal Governments
to accelerate the implementation and adoption of proven innovative
technologies. Project activities may involve any phase of a highway
transportation project from project planning through project delivery.
Complementary Strategies
Digital strategies, including smart phone apps and advanced scheduling and routing systems, support micromobility
delivery services. Freight digitalization strategies, such as GPS tracking and eco-routing, streamline dispatch and route
optimization, enabling micromobility deliveries to efficiently navigate congested urban areas.
Parking reform strategies, such as smart parking, curb management strategies, and other on- and off-street parking
solutions for freight deliveries, rely on freight digitalization technology to reduce congestion and time lost to circling and
idling.
Freight digitalization strategies, such as real-time tracking systems and predictive analytics, allow logistics operators to
optimize delivery routes and schedules, identifying opportunities for off-peak delivery based on factors like traffic patterns,
delivery windows, and customer preferences. In addition, curb reservation systems, common carrier lockers, and other
technological solutions can facilitate deliveries during off-peak hours.
Digital solutions can support intermodal freight logistics through advanced tracking and scheduling systems and
optimizing freight movements based on commodity, tonnage, and other factors.
Case studies
The City of Pittsburgh and Pittsburgh Parking Authority have implemented Smart Loading Zones, using Automotus curb management technology, as
a way to manage curb space to increase delivery efficiency and decrease congestion and emissions at curbs. License plate sensors are used to
analyze curbside activity and automate payment for the duration a vehicle is parked at a curb. The smart zones are expected to decrease emissions
from unnecessary idling and circling, reduce parking-related congestion, improve pedestrian and cyclist safety, and increase parking turnover in
business districts.
Flytrex, a drone delivery service, is currently operating in Texas and North Carolina. Flytrex flies commercial drones and make deliveries to
residential backyards and parks for restaurants and retailers. In 2020, the company partnered with the North Carolina Department of
Transportation as part of the FAA's BEYOND program which is working towards drone operation without visual ground monitoring. In North
Carolina, Flytrex makes deliveries to neighborhoods in Holly Springs, Durham, and Raeford, with plans to expand to additional areas over the next
few years. Users can order food and other items from a list of restaurants and grocery stores on an app. The program has been shown to be safe,
energy efficient, and can help reduce traffic from delivery vehicles in neighborhoods.
Perishables have traditionally been transported almost exclusively by truck (e.g., in 2014, only 2% of fresh produce shipped with the U.S. used
intermodal transport). Railex provides transportation and logistics services for perishable cargo. Railex began using refrigerated boxcars and
warehouses with climate controls specific to each produce type, automated temperature and humidity controls in railcars, accelerometers to
evaluate in-transit events that could damage cargo, and digital inventory management. With the aid of advanced technology, they report cost
savings of 10-20% coast-to-coast relative to long-haul trucking.
In 2021, the City of Nashville, in partnership with Coord (now Pebble),
a curb management company, launched a Smart Zone Pilot to better
manage curb space in the downtown area. Smart Zones enable
commercial drivers to use mobile devices to locate, reserve, and pay
for time in available loading zones. The Nashville pilot included 14
Smart Zones and over 21 delivery fleets. Nashville was one of four
cities selected for Smart Zone pilot in addition to Aspen, CO, Omaha,
NE, and West Palm Beach, FL.
Smart Zones allow drivers to find and book available loading zones using a
smartphone app (Source: Hammon, 2021).
Implementing Freight Digital Solutions and
Emerging Technologies:
What to Read Next
The Urban Freight Lab, a public-private partnership at the University
of Washington, provides several resources on the benefits of freight
technologies, including:
- Final 50 Feet Research Program: the final 50 feet journey involves a
“delivery driver searching for adequate parking, then transferring
items from the delivery truck, navigating a route across traffic and
through urban obstacle…, concluding when the intended recipient
takes receipt of their parcel.” Common Carrier Lockers are one
digital solution to the final 50 feet problem. - Curb Occupancy Toolkit: allows for study of the parking behavior
of commercial vehicles along the block face and within commercial
vehicle loading zones.
The American Council for an Energy-Efficient Economy’s (ACEEE) brief,
Leveraging Digital Freight Networks to Reduce Emissions, provides
policymakers with information on the potential impact of digital
freight networks (DFNs) on freight efficiency and emissions in the U.S.
Optimizing the movement of goods through information and
communications technology (ICT) will be key in achieving substantial
reductions in freight-related GHGs.
- DFNs pool data to match shipments to trucks, which can add
capacity, improve efficiency, and lower costs to shippers and
carriers. Policy makers and industry can coordinate to maximize
the benefits of DFNs. - Uber Freight estimates that with perfect optimization of the U.S.
freight network, achieved in part through the use of DFNs, empty
miles could be reduced by up to 64% ((Uber Freight, 2023).
In 2022, the International Transport Forum published How Digitally-
driven Operational Improvements Can Reduce Global Freight Emissions.
The report presents results from a scenario analysis comparing the
impact of different freight digitalization strategies on global CO₂
emissions in 2025, 2030, and 2050. Key strategies include: improving
truck utilization, strengthening port capacity, adopting ITS, and
reducing intermodal dwell time.
The Truck Parking Information Management System (TPIMS),
established with FHWA grant funding by eight member states of the
Mid America Association of State Transportation System, provides real
time parking availability to drivers along major freight corridors, so
that they may proactively plan their routes and make safer, smarter
parking decisions.
Resources
FMSCA SAFESPECT Screening Platform: FMSCA recently announced this next generation digital inspection platform for commercial vehicle roadside
safety inspections. SAFESPECT will improve the efficiency of inspections and decrease wait and vehicle idling time at inspection stations.
FHWA CARMA Program: This program is leading research on cooperative driving automation (CDA) which would enable communication and
cooperation between properly equipped vehicles and infrastructure.
DOE CDA Funding Programs: DOE supports CDA research through funding for New Mobility Systems and through the ARPA-E NEXTCAR Program.
CDA technologies have the potential to reduce congestion and increase the safety and efficiency of travel on roadways.
FHWA and BTS Freight Analysis Framework (FAF): The FHWA and BTS database contains freight flow data sourced from a variety of sectors, to
support freight analysis and inform decision-making. The database provides a comprehensive summary of current freight trends and can be used to
predict future trends.
US DOT Freight Logistics Optimization Works (FLOW): Developed by U.S. DOT, FLOW provides an industry forum combined with an information
exchange platform to help address supply chain challenges and enable a resilient and globally competitive 21st century freight network.
General Resources
Toolkits and Modelling Approaches
See the References section for modeling studies on digital freight and associated climate benefits.
References
Cleantech Group. (2021). Smart Cities and Curb Management: Innovating for Success. https://www.cleantech.com/smart-cities-and-curb-
management-innovating-for-success/
Drexl, M. (2012). Rich vehicle routing in theory and practice. Logistics Research, 5, 47-63. https://doi.org/10.1007/s12159-012-0080-2
Engage Pittsburgh. (2024). Smart Loading Zones. https://engage.pittsburghpa.gov/smart-loading-zones
Freightpriority EcoDrive. (2024). https://freightpriority.com/
Goodchild, A., & Toy, J. (2018). Delivery by drone: An evaluation of unmanned aerial vehicle technology in reducing CO2 emissions in the delivery
service industry. Transportation Research Part D: Transport and Environment, 61, 58-67. https://doi.org/10.1016/j.trd.2017.02.017
Hammon, Mary. (2021). Manage the curb with smart loading zones. American Planning Association.
https://www.planning.org/planning/2021/winter/manage-the-curb-with-smart-loading-zones/
International Transport Forum (ITF). (2022). Organization for Economic Co-operation and Development. How Digitally-driven Operational
Improvements Can Reduce Global Freight Emissions. https://www.itf-oecd.org/digitally-driven-operational-improvements-freight-emissions-
reduction
Jaller, M., Pahwa, A., & Region, P. S. (2021). Cargo Routing and Disadvantaged Communities [supporting datasets] (No. PSR-UCD-19-43). United
States. Dept. of Transportation. Office of the Assistant Secretary for Research and Technology. https://rosap.ntl.bts.gov/view/dot/58491
Kechagias, E. P., Gayialis, S. P., Konstantakopoulos, G. D., & Papadopoulos, G. A. (2020). An application of an urban freight transportation system for
reduced environmental emissions. Systems, 8(4), 49. https://doi.org/10.3390/systems8040049
Kirschstein, T. (2020). Comparison of energy demands of drone-based and ground-based parcel delivery services. Transportation Research Part D:
Transport and Environment, 78, 102209. https://www.sciencedirect.com/journal/transportation-research-part-d-transport-and-environment
Nakajima, C. (2024). Leveraging digital freight networks to reduce emissions. ACEEE. https://www.aceee.org/topic-brief/2024/01/leveraging-digital-
freight-networks-reduce-emissions
NREL. (2021). Google Taps NREL Expertise To Incorporate Energy Optimization into Google Maps Route Guidance.
https://www.nrel.gov/news/program/2021/google-taps-nrel-expertise-to-incorporate-energy-optimization-into-google-maps-route-guidance.html
Office of Transportation and Air Quality. (2014). Near Roadway Air Pollution and Health: Frequently Asked Questions. FAQ, EPA-420-F-14-044, U.S.
Environmental Protection Agency, https://www.epa.gov/sites/default/files/2015-11/documents/420f14044_0.pdf.
Outay, F., Kamoun, F., Kaisser, F., Alterri, D., & Yasar, A. (2019). V2V and V2I communications for traffic safety and CO emission reduction: a
performance evaluation. Procedia Computer Science, 151, 353-360. DOI:10.1016/j.procs.2019.04.049
Pyzyk, K. (2019). CurbFlow pilot reduced double parking in DC by 64%. Smart Cities Dive. https://www.smartcitiesdive.com/news/curbflow-pilot-
reduced-double-parking-in-dc-by-64/567268/
Schulte, F., Lalla-Ruiz, E., González-Ramírez, R. G., & Voß, S. (2017). Reducing port-related empty truck emissions: a mathematical approach for truck
appointments with collaboration. Transportation Research Part E: Logistics and Transportation Review, 105, 195-212.
https://doi.org/10.1016/j.tre.2017.03.008
StreetLight. (2024). Investigating how trucks impact social equity with new freight data. https://www.streetlightdata.com/investigating-equity-with-
new-truck-data/
Uber Freight. (2023). Uber Freight research shows ⅔ of empty miles can be eliminated—here’s how. https://www.uberfreight.com/blog/uber-freight-
research-shows-%E2%85%94-of-empty-miles-can-be-eliminated-heres-how/
U.S. Department of Transportation (USDOT). (2023). The Critical Role of Rural Communities in the U.S. Transportation System.
https://www.transportation.gov/rural/grant-toolkit/critical-role-rural-communities
United Parcel Service (UPS). (2009). UPS Sustainability Report, 2009. https://about.ups.com/content/dam/upsstories/assets/reporting/2009-UPS-
Corporate-Sustainability-Report.pdf
World Economic Forum (WEF). (2016). Digital Transformation of Industries: Logistics Industry, World Economic Forum White Paper.
https://www.weforum.org/publications/digital-transformation-of-industries/.
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For more information visit the DOT Climate Change Center,
https://www.transportation.gov/priorities/climate-and-
sustainability/dot-climate-change-center