The Trillion Dollar Question II: Tracking Investment Needs in Transport

This research paper estimates that annual global transport infrastructure investment needs are $2 trillion for a 2°C scenario and $2.3 trillion for a 4°C scenario. It concludes that a low-carbon pathway is more affordable and financially feasible within current annual investment flows of $1.4 to $2.1 trillion, provided that national policymakers and development banks shift investment portfolios toward sustainable options.

• Annual investment needs for global transport infrastructure are estimated at $2 trillion to achieve a 2 degree scenario and $2.3 trillion for a 4 degree scenario. The 4 degree scenario is projected to be more expensive when accounting for external costs such as urban sprawl, air quality, and congestion.
• A low-carbon 2 degree scenario is considered financially feasible because it falls within the current global capital investment flows for public and private transport, which are estimated to be between $1.4 trillion and $2.1 trillion annually.
• Achieving a low-carbon transport scenario requires shifting investment portfolios and policies toward sustainable options. This process depends on the actions of multilateral development banks and domestic policy leaders, including directors of national development banks and ministers of transport and finance.

APA

World Resources Institute (n.d.). The Trillion Dollar Question II: Tracking Investment Needs in Transport. https://www.wri.org/research/trillion-dollar-question-ii-tracking-investment-needs-transport

Chicago

World Resources Institute. The Trillion Dollar Question II: Tracking Investment Needs in Transport. n.d. https://www.wri.org/research/trillion-dollar-question-ii-tracking-investment-needs-transport.

Wikipedia

{{cite report |author=World Resources Institute |title=The Trillion Dollar Question II: Tracking Investment Needs in Transport |url=https://www.wri.org/research/trillion-dollar-question-ii-tracking-investment-needs-transport |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{worldresourcesinstitutendtrillion, author = {{World Resources Institute}}, title = {{The Trillion Dollar Question II: Tracking Investment Needs in Transport}}, institution = {World Resources Institute}, url = {https://www.wri.org/research/trillion-dollar-question-ii-tracking-investment-needs-transport}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }