Rising Sea Levels Will Hit California Hard in the Next Years
California’s beaches – with their white sand and high palm trees – are a popular attraction point for travelers around the world. However, due to the melting of massive ice sheets in Antarctica, the sunny state will experience greater rising sea levels than other places around the globe. The threat to California’s important infrastructure was highlighted in a report published Wednesday.
According to the California government council conducting the report, the worst-case scenario sees the sea-level increase by almost 10 feet by the end of the century. Should they come true, the changes would flood roadways and wipe out airports in San Francisco and Oakland. It would also mean a never-seen-before swamping of railroad tracks, low bridges, beaches, and even some towns.
An advisory team with the California Ocean Protection Council warned that as many as 42,000 homes could end up submerged. The first draft of the report was released earlier this month, but this week the council adopted an updated report, which includes the rising sea-level estimates.
Increasing Rate of Ice Loss Causes Rising Sea Levels
According to the latest science, Greenland and Antarctica are both losing ice coverage at an increasing pace. This will soon become the main driver behind global sea-level rise, overtaking warming ocean waters and the melting of ice caps and mountain glaciers. The study showed the ice loss is causing particularly rising sea levels in California because of the Earth’s rotation and the gravitational pull on the ocean. If ice in West Antarctica starts melting, the effects will extend even further.
As far as California is concerned, the melting of the West Antarctic Ice Sheet is the worst thing that can happen. If the ice on West Antarctica causes just one foot of global rise of the sea level, the California coast experiences a rise of around 1.25 feet. The effects are staggering, which is why the advisory team is trying to warn concerned authorities about the imminent problem.
Dan Cayan, head of the Climate Research Division at the San Diego Scripps Institution of Oceanography, explained that increased land ice melting in Antarctica essentially puts the highest pressure on the Californian coast. Cayan is part of a seven-scientist author team. They based their study on a related report conducted in 2010 and updated in 2013.
The latest update was essential because scientists worldwide have come up with new data and more accurate forecast on sea-level rise. During the spring and summer of 2017, the council will conduct seminars on the research and take comments. By fall, they hope to announce a draft proposal that will turn into policy. If all goes well, the changes should receive approval by January 2018.
Effects Already Visible
The study pointed out that sea-level rise is already disturbing coastal California. Among the repercussions are regular tidal flooding, major coastal deluges during storms, and heightened coastal erosion. The state also faces rising sea levels over the short term, caused by El Niño. During this natural phenomenon, the central waters of the Pacific Ocean experience warming. El Niño can also kick off forceful storms. When coupled with higher sea levels, these storms can trigger floods, mudslides, and avalanches in the mountains.
There’s no doubt the global sea levels will continue to increase. However, the exact amounts are still unclear, since there are several contributing factors. Among the most important is the way countries respond to the rising sea levels. The key to combating this is successfully curbing greenhouse gas emissions and reducing temperature rise.
When it comes to various sea-level rise projections until 2050, only minor differences exist between studies. However, the study’s estimations, which focus on GHG pollution scenarios, diverge greatly after the middle of the century. The advisory panel looked at three California locations in their study. The possible sea-level rise predictions focused on three areas with tide gauges: the Golden Gate Bridge in San Francisco, Crescent City in northern California, and La Jolla in San Diego.
By the century’s end and according to the base estimates, the sea would rise in San Francisco by 1 foot. The worst-case scenario, however, shows an increase of as much as 6.9 feet. In La Jolla, the estimates range between 1.1 feet and 7.2 feet sea rise.
Report Praises and Critics
But are the report’s estimates accurate? The authors themselves said their projections could plunge way below the actual changes. They worry concerned authorities might use them to underestimate the possibility of severe sea-level rise. In high GHG emissions scenarios, for instance, California could experience a 10-foot increase by the turn of the century.
The California Ocean Protection Council presented the report at an open meeting on Wednesday. Some of the participating speakers – including a California Coastal Commission official – expressed concern that the report’s low estimates could mislead the public.
The study’s projections “could have the unintended consequence of reducing or reversing the progress that is being made in planning for sea-level rise,” said Madeline Cavalieri, a coastal planner at the California Coastal Commission.
According to other people present at the meeting, the low scenarios fail to account for the latest figures published on ice sheet loss. However, Cavalieri also praised the advisory team for including the maximum scenario with the potential 10-feet increase. She hopes the warning will prompt organized planning to defend critical infrastructure in the state.
But David Behar, the director of the climate program at the San Francisco Public Utilities Commission, disagrees. He cautioned the report should be more clear about the source of its ‘10-feet’ scenario. Not even NOAA’s report on rising sea levels proposed such a high number, nor other reports on the matter. Understanding where that figure comes from will help the public understand how to react to it.
Plans for the Future
The report urges statewide infrastructure planning, not just coastal. For instance, authorities should address the issues in the Sacramento-San Joaquin River Delta, the structure that supplies the majority of the state with drinking water. If the delta’s islands are overtopped, the salinity gradient and the circulation would suffer.
California has to assume its role as a leader in this respect, given the importance of the problem. Due to its geopolitical location, a lot of people are in harm’s way. The issue of social justice also comes into play, seeing that some cities may be more vulnerable than others. Not all the local authorities can afford to erect a sea wall or protect their infrastructure.