This study presents an integrated assessment of deep decarbonization scenarios for the global transportation sector, aiming to keep end-of-century warming below 1.5°C. Using the Global Change Analysis Model (GCAM) version 6.0, the research evaluates high, medium, and low ambition scenarios for decarbonizing all transportation modes, including aviation and shipping. The high ambition scenario eliminates transportation emissions by mid-century, significantly contributing to climate targets but requiring rapid technological shifts. Electrification is the primary driver of decarbonization across the sector, with biofuels and hydrogen playing key roles in aviation and shipping. The study highlights the importance of low carbon technologies for each mode, showing that electrification contributes most to decarbonization, while hydrogen and biofuels are crucial for long-distance travel. The transportation sector is one of the most challenging to decarbonize due to its reliance on oil and the distributed nature of emissions. The study finds that electrification, hydrogen, and biofuels are the leading low carbon technologies for different modes. However, aviation and shipping face unique challenges due to the need for reliable, energy-dense fuels and long vehicle lifespans. The study also considers the interactions between the transportation sector and other sectors, showing that the development of low carbon technologies for aviation and shipping is essential for achieving deep decarbonization. The study finds that the high ambition scenario reduces global transportation emissions by 675 Gt CO2 compared to the reference scenario, with significant reductions in emissions from aviation and shipping. The study also highlights the importance of hydrogen and alternative liquid fuels for long-haul aviation and shipping, with e-fuels being less cost-competitive than biofuels. The study also considers the impacts of different scenarios on other sectors, showing that the high ambition scenario requires less emissions mitigation in other sectors due to the reduced emissions from transportation. The study also explores the implications of different scenarios on fuel and resource demands, showing that the high ambition scenario requires significant increases in hydrogen and alternative liquid fuel consumption. The study also considers the impacts of different scenarios on the upstream production of fuels, showing that the high ambition scenario requires significant decarbonization of upstream production to ensure zero emissions. The study also highlights the importance of financial and policy incentives in ensuring the competitiveness of low carbon technologies in transport. The study concludes that achieving deep decarbonization in the transportation sector will require significant technological transitions, with electrification, hydrogen, and biofuels playing key roles. The study also highlights the importance of considering the broader implications of these transitions, including the impacts on resource availability, infrastructure development, and supply chain management.This study presents an integrated assessment of deep decarbonization scenarios for the global transportation sector, aiming to keep end-of-century warming below 1.5°C. Using the Global Change Analysis Model (GCAM) version 6.0, the research evaluates high, medium, and low ambition scenarios for decarbonizing all transportation modes, including aviation and shipping. The high ambition scenario eliminates transportation emissions by mid-century, significantly contributing to climate targets but requiring rapid technological shifts. Electrification is the primary driver of decarbonization across the sector, with biofuels and hydrogen playing key roles in aviation and shipping. The study highlights the importance of low carbon technologies for each mode, showing that electrification contributes most to decarbonization, while hydrogen and biofuels are crucial for long-distance travel. The transportation sector is one of the most challenging to decarbonize due to its reliance on oil and the distributed nature of emissions. The study finds that electrification, hydrogen, and biofuels are the leading low carbon technologies for different modes. However, aviation and shipping face unique challenges due to the need for reliable, energy-dense fuels and long vehicle lifespans. The study also considers the interactions between the transportation sector and other sectors, showing that the development of low carbon technologies for aviation and shipping is essential for achieving deep decarbonization. The study finds that the high ambition scenario reduces global transportation emissions by 675 Gt CO2 compared to the reference scenario, with significant reductions in emissions from aviation and shipping. The study also highlights the importance of hydrogen and alternative liquid fuels for long-haul aviation and shipping, with e-fuels being less cost-competitive than biofuels. The study also considers the impacts of different scenarios on other sectors, showing that the high ambition scenario requires less emissions mitigation in other sectors due to the reduced emissions from transportation. The study also explores the implications of different scenarios on fuel and resource demands, showing that the high ambition scenario requires significant increases in hydrogen and alternative liquid fuel consumption. The study also considers the impacts of different scenarios on the upstream production of fuels, showing that the high ambition scenario requires significant decarbonization of upstream production to ensure zero emissions. The study also highlights the importance of financial and policy incentives in ensuring the competitiveness of low carbon technologies in transport. The study concludes that achieving deep decarbonization in the transportation sector will require significant technological transitions, with electrification, hydrogen, and biofuels playing key roles. The study also highlights the importance of considering the broader implications of these transitions, including the impacts on resource availability, infrastructure development, and supply chain management.