Without aggressive and sustained policy intervention, direct transport carbon emissions could double by 2050. This contribution is rising faster than for any other energy end-use sector. Transport Demand on the RiseTransport accounts for about a quarter of global energy-related carbon emissions. For international shipping, combined technical and operational changes can massively reduce energy use. Truck modernisation including increased freight load, along with engine, tyre and vehicle maintenance, can significantly improve fuel economy. Frequent freeze-thaw cycles in cold regions will damage both the base and paved surface. Unpaved roads and bridges are especially vulnerable to intense rainfall. RoadExtreme heat will soften paved roads. Higher temperatures at high-altitude and low-latitude airports may reduce the maximum take-o weight or require longer runways due to less dense air. AviationMore storms in some regions may increase the number of weather-related delays and cancellations. RailIncreased rainfall, flooding and subsidence, sea-level rise and increased incidence of freeze- thaw cycles undermine the stability of railways. Eciency of new-built vessels can be improved by 5–30%. Port infrastructure may need to be rebuilt to avoid the worst impacts of sea-level rise. Fuel eciency gains of 40ⅅ0% from 2030⅂050 can be achieved through improved design. The high-speed ‘Shinkansen’ commuter train in Japan reduced energy consumption by 40%. In China, electrification and other measures on train infrastructure from 1975 to 2007 helped reduce CO2 emission intensity by 87%. Electric hybrid drive trains, buses and cars can reduce consumption by 35% compared with conventional engines. Infographic: Climate Change and Transportīetter air trac management can reduce CO2 emissions through more direct routings and flying at optimum altitudes and speed.