The U.S. Department of Transportation (DOT) released a study on the potential impacts of climate changes and land subsidence on transportation infrastructure in the U.S. Gulf Coast region. The Impacts of Climate Change and Variability on Transportation Systems and Infrastructure: Gulf Coast Study, Phase I (phase one of a three-part study), assesses the vulnerabilities of transportation systems in the region to potential changes in weather patterns and related impacts, as well as the effect of natural land subsidence and other environmental factors in the region. The area examined by the study includes 48 contiguous counties in four states, running from Galveston, Texas, to Mobile, Ala.

Based on 21 simulation models and a range of emissions scenarios, the study found that potential changes in climate during the next 50 to 100 years could disrupt transportation services in the region. Twenty-seven percent of major roads, 9 percent of rail lines, and 72 percent of area ports are at or below 4 feet in elevation, and could be vulnerable to flooding caused by future sea level rise and natural sinking of the area’s land mass. According to the DOT, the study is designed to help state and local officials as they develop their transportation plans and make investment decisions.

Subsequent phases of the study will focus on risks and adaptation strategies involved in planning, investment, design, and operational decisions for infrastructure in the Gulf Coast region and nationwide. The study was
performed in partnership with the U.S. Geological Survey and state and local researchers, and is one of 21 "synthesis and assessment" reports produced as part of the U.S. Climate Change Science Program.

The study is available online here (10.0 MB PDF).