title: Climate change damages to Alaska public infrastructure and the economics of proactive adaptation.
abstract: Climate change in the circumpolar region is causing dramatic environmental change that is increasing the vulnerability of infrastructure. We quantified the economic impacts of climate change on Alaska public infrastructure under relatively high and low climate forcing scenarios [representative concentration pathway 8.5 (RCP8.5) and RCP4.5] using an infrastructure model modified to account for unique climate impacts at northern latitudes, including near-surface permafrost thaw. Additionally, we evaluated how proactive adaptation influenced economic impacts on select infrastructure types and developed first-order estimates of potential land losses associated with coastal erosion and lengthening of the coastal ice-free season for 12 communities. Cumulative estimated expenses from climate-related damage to infrastructure without adaptation measures (hereafter damages) from 2015 to 2099 totaled $5.5 billion (2015 dollars, 3% discount) for RCP8.5 and $4.2 billion for RCP4.5, suggesting that reducing greenhouse gas emissions could lessen damages by $1.3 billion this century. The distribution of damages varied across the state, with the largest damages projected for the interior and southcentral Alaska. The largest source of damages was road flooding caused by increased precipitation followed by damages to buildings associated with near-surface permafrost thaw. Smaller damages were observed for airports, railroads, and pipelines. Proactive adaptation reduced total projected cumulative expenditures to $2.9 billion for RCP8.5 and $2.3 billion for RCP4.5. For road flooding, adaptation provided an annual savings of 80-100% across four study eras. For nearly all infrastructure types and time periods evaluated, damages and adaptation costs were larger for RCP8.5 than RCP4.5. Estimated coastal erosion losses were also larger for RCP8.5.
authors.affiliation: American Association for the Advancement of Science (AAAS) Science & Technology Policy Fellow, Climate Change Division, US Environmental Protection Agency, Washington, DC 20460.
authors.forename: April M
authors.initials: AM
authors.lastname: Melvin
authors.affiliation: Independent Consultant, Helena, MT 59601.
authors.forename: Peter
authors.initials: P
authors.lastname: Larsen
authors.affiliation: Industrial Economics, Inc., Cambridge, MA 02140.|Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA 02139.
authors.forename: Brent
authors.initials: B
authors.lastname: Boehlert
authors.affiliation: Industrial Economics, Inc., Cambridge, MA 02140.
authors.forename: James E
authors.initials: JE
authors.lastname: Neumann
authors.affiliation: Resilient Analytics, Boulder, CO 80309.
authors.forename: Paul
authors.initials: P
authors.lastname: Chinowsky
authors.affiliation: Resilient Analytics, Boulder, CO 80309.
authors.forename: Xavier
authors.initials: X
authors.lastname: Espinet
authors.affiliation: Climate Change Division, US Environmental Protection Agency, Washington, DC 20460; martinich.jeremy@epa.gov.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Martinich
authors.affiliation: Industrial Economics, Inc., Cambridge, MA 02140.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Baumann
authors.affiliation: Industrial Economics, Inc., Cambridge, MA 02140.
authors.forename: Lisa
authors.initials: L
authors.lastname: Rennels
authors.affiliation: Industrial Economics, Inc., Cambridge, MA 02140.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Bothner
authors.affiliation: Geophysical Institute, University of Alaska, Fairbanks, AK 99775.
authors.forename: Dmitry J
authors.initials: DJ
authors.lastname: Nicolsky
authors.affiliation: Geophysical Institute, University of Alaska, Fairbanks, AK 99775.
authors.forename: Sergey S
authors.initials: SS
authors.lastname: Marchenko
keywords: Alaska; adaptation; climate change; damages; infrastructure