title: Quantifying carbon mitigation wedges in U.S. cities: near-term strategy analysis and critical review.
abstract: A case study of Denver, Colorado explores the roles of three social actors-individual users, infrastructure designer-operators, and policy actors-in near-term greenhouse gas (GHG) mitigation in U.S. cities. Energy efficiency, renewable energy, urban design, price- and behavioral-feedback strategies are evaluated across buildings-facilities, transportation, and materials/waste sectors in cities, comparing voluntary versus regulatory action configurations. GHG mitigation impact depends upon strategy effectiveness per unit, as well as societal participation rates in various action-configurations. Greatest impact occurs with regulations addressing the vast existing buildings stock in cities, followed by voluntary behavior change in electricity use/purchases, technology shifts (e.g., to teleconferencing), and green-energy purchases among individual users. A portfolio mix of voluntary and regulatory actions can yield a best-case maximum of ~1% GHG mitigation annually in buildings and transportation sectors, combined. Relying solely on voluntary actions reduces mitigation rates more than five-fold. A portfolio analysis of climate action plans in 55 U.S. cities reveals predominance of voluntary outreach programs that have low societal participation rates and hence low GHG impact, while innovative higher-impact behavioral, technological, and policy/regulatory strategies are under-utilized. Less than half the cities capitalize on cross-scale linkages with higher-impact state-scale policies. Interdisciplinary field research can help address the mis-match in plans, actions, and outcomes.
authors.affiliation: Center for Sustainable Infrastructure Systems, University of Colorado Denver, Denver, Colorado, United States. anu.ramaswami@ucdenver.edu
authors.forename: Anu
authors.initials: A
authors.lastname: Ramaswami
authors.forename: Meghan
authors.initials: M
authors.lastname: Bernard
authors.forename: Abel
authors.initials: A
authors.lastname: Chavez
authors.forename: Tim
authors.initials: T
authors.lastname: Hillman
authors.forename: Michael
authors.initials: M
authors.lastname: Whitaker
authors.forename: Gregg
authors.initials: G
authors.lastname: Thomas
authors.forename: Matthew
authors.initials: M
authors.lastname: Marshall
mesh_terms: D002244:Carbon / Q000032:analysis*; D002947:Cities; D005160:Facility Design and Construction; D017752:Greenhouse Effect / Q000517:prevention & control*; D006801:Humans; D014186:Transportation; D014481:United States
chemical_list: D002244:Carbon