Climate Assessment for Southwest States Examines Coastal Issues

New Report Assesses Climate Change Risks and Options for California’s Coast

Climate change puts thousands of coastal residents and billions of dollars in infrastructure and resources at risk

Coastal Erosion in California

The ever-changing California coast is about to experience an even greater degree of transformation due to climate change, and it’s up to coastal managers to figure out how to respond to changes that could potentially impact thousands of residents, billions of dollars of resources and invaluable marine ecosystems. To help coastal managers perform this herculean task, the Center for Ocean Solutions teamed with other researchers to craft an in-depth chapter dedicated to coastal issues as part of the “Assessment of Climate Change in the Southwest United States.”

“Since the California coast is an area of high economic and environmental value, our analysis of coastal issues delves into the major climate change impacts coastal managers should consider,” explained Meg Caldwell, executive director of the Center for Ocean Solutions and a coordinating lead author of the Coastal Issues chapter. “The chief challenges are sea level rise that could inundate power plants, airports and homes, ocean warming that can result in harmful algal blooms and ocean acidification that may cause the decline of economically valuable shellfish and coral. We detail the risks, but we also explain viable coastal adaptation options.”

Landmark study

The “Assessment of Climate Change in the Southwest United States” is a major study that blends the work of 120 experts in climate change, resource management, environmental law and policy, economics, engineering and other disciplines. The book—one of 10 regional technical inputs to the 2013 “National Climate Assessment,”—stresses the choices and opportunities communities have to reduce the causes and impacts of climate change on the natural environment and human assets.

SW Climate Assessment cover

“Among the major impacts in California is rising sea levels,” commented Eric Hartge, research analyst at the Center for Ocean Solutions and a coordinating lead author of the Coastal Issues chapter. “The sea level along the California coast has already risen about eight inches in the past century, and scientists expect it to rise another one to three feet by 2100. Runways at both the San Francisco and Oakland airports will begin to flood if seas rise 16 inches above a year 2000 baseline and no protective actions are taken. Since 70 percent of the state’s residents live in coastal counties, how to respond to this issue is clearly on the minds of coastal managers, according to research.” 

Impacts to California coasts

Sea level rise causes coastal erosion, and California could be faced with the loss of as many as 9,000 acres of dunes and 17,000 acres of coastal bluffs by 2100. Coastal communities have various options for addressing these impacts, including coastal protection through an increased use of sea walls or natural infrastructure, adapting coastal development methods to decrease risk, and planned retreat whereby human infrastructure is moved inland. Each of these approaches has costs and consequences that are discussed in the report.

Among the major recommendations to cope with climate change impacts along the California Coast is the reform of many federal and state-funded programs and activities that protect and even subsidize high-risk coastal development. For example, federal flood insurance programs need to be reformed to fully reflect the risk policy holders face and government infrastructure projects such as sea walls and dikes should not facilitate development in at-risk areas.

Sand dredging Del Mar, Calif.

This 531-page study was released on May 2 with a press conference at the University of Arizona and distribution of the book through Island Press, Amazon and other outlets. Ocean and coastal managers in federal, state, regional and county agencies will find a wealth of information in this publication, as will local communities, businesses, organizations and individuals concerned with the health of the ocean and California’s coasts.

Interdisciplinary collaboration of scientists and policy experts

Authored by scientists and policy experts, the “Coastal Issues” chapter reflects contributions by a number of the Center for Ocean Solutions team. In addition to Caldwell, who holds a J.D. and serves on the California Coastal Commission, and Hartge, who holds an M.S. in environmental sciences and policy, lead authors include Ryan P. Kelly, a visiting fellow with a Ph.D. in biology and a J.D.; Susanne C. Moser, a COS affiliated researcher who holds a Ph.D. in geography; and C. Brock Woodson, also an affiliated researcher with a Ph.D. in civil engineering.

Coastal development in Southern California

Other lead authors on the work are Lesley C. Ewing, a senior coastal engineer with the California Coastal Commissions; Gary Griggs, a distinguished professor of earth sciences of University of California, Santa Cruz; Sarah G. Newkirk, a coastal team lead at The Nature Conservancy, and Rebecca A. Smyth, West Coast Director/Regional Division Chief at NOAA Coastal Services Center.

Photos: Gary Griggs, University of California, Santa Cruz; Jennifer Wolf/WolfHartt Image/Marine Photobank; (c) Wolcott Henry 2005/Marine Photobank