Road sign warns of flooding in Wachapreague, Virginia on Tuesday, July 10, 2018. (Photo by Aileen Devlin / Virginia Sea Grant) Creative Commons license via Flickr
By Sunny Lewis
ISPRA, Italy, August 14, 2018 (Maximpact.com News) – Famous Hawaiian swimmer and surfer Duke Kahanamoku always warned, “Never turn your back on the ocean.” He wanted people to watch out for the physical dangers of being hit by a wave from behind, and he wanted humankind to show respect for the ocean – a warning that today is more urgent than ever.
The findings of two Joint Research Centre (JRC) studies released on Monday show that without increased investment in coastal adaptation, the annual damage caused by coastal floods in Europe could increase from €1.25 billion today to between €93 billion and €961 billion by the end of the century.
One in three citizens of the European Union lives within 50 kilometers (30 miles) of the coast. Due to an increase in extreme sea levels driven by global warming, coastal floods could impact up to 3.65 million people every year in Europe by 2100, compared to around 102,000 people affected today.
In the JRC studies scientists project both how global extreme sea levels will change during the present century, and also how rising seas combined with socioeconomic change will affect future losses from coastal flooding.
Sea levels are rising, and the trajectory is expected to continue beyond the year 2100, even if greenhouse gas emissions are stabilized right now. Most scientists expect the sea to rise by at least one meter (39 inches) during this century, and many believe sea levels may even rise three meters by 2100, in view of new evidence on ice-cliff instability of the Antarctic.
Antarctica alone has the potential to contribute more than a meter of sea-level rise by 2100 and more than 15 meters by 2500, if emissions continue unabated, finds a 2016 study by Robert DeConto of the University of Massachusetts’ Department of Geosciences, and David Pollard of Penn State University’s Earth and Environmental Systems Institute.
DeConto and Pollard warn that atmospheric warming will become the dominant driver of ice loss, and prolonged ocean warming will delay ocean recovery for “thousands of years.”
With continued ocean and atmospheric warming, sea levels are likely to rise for many centuries at rates higher than that of the current century, according to the U.S. National Oceanic and Atmospheric Administration (NOAA).
Flood damage to the city of Ōfunato, Iwate Prefecture, Japan caused by the 2011 tsunami that caused a meltdown at the coastal nuclear power plant in Fukushima, Japan. July 2011, (Photo by George Olcott) Creative Commons license via Flickr
Global warming is expected to drive increasing extreme sea levels and flood risk along all the world’s coastlines. This year sea levels continue their upward movement, rising about three inches higher than levels measured in 1993.
Higher sea levels mean that deadly and destructive storm surges push farther inland than they once did, causing more frequent flooding.
In cities, rising seas threaten infrastructure underpinning local jobs and regional industries. Roads, bridges, subways, water supplies, oil and gas wells, power plants, sewage treatment plants, landfills – virtually all human infrastructure – is at risk from sea level rise, NOAA warns.
European scientists are issuing equally urgent warnings of “unprecedented flood risk unless timely adaptation measures are taken.”
The JRC researchers considered two scenarios – one where moderate policy efforts are made to mitigate climate change and a business as usual situation.
They concluded that in order for Europe to keep future coastal flood losses constant relative to the size of the economy, defense structures need to be installed or reinforced to withstand increases in extreme sea levels ranging from 0.5 to 2.5 meters (1.64 to 8.2 feet).
The researchers identified climate change as the main driver of the projected rise in costs from coastal flooding. This is a change from the current situation globally, where increasing risk has been driven by socioeconomic development.
In the United States, almost 40 percent of the population lives in high-population-density coastal areas, where sea level plays a role in flooding, shoreline erosion, and hazards from storms.
Globally, eight of the world’s 10 largest cities are near a coast, according to the United Nations Atlas of the Oceans . These are the cities most at risk of sea level rise. They are: Tokyo, Japan; Mumbai, India; New York City, USA; Shanghai, China; Lagos, Nigeria; Los Angeles, USA; Calcutta, India; and Buenos Aires, Argentina.
A flood inundates St. Marks Square in Venice, Italy, October 10, 2017 (Photo by Konstantinos Tamvakis)
The frequency and severity of coastal flooding throughout the world will increase rapidly and eventually double in frequency over the coming decades even with only moderate amounts of sea level rise, according to a 2017 study in “Scientific Reports” from scientists at the U.S. Geological Survey, the University of Illinois at Chicago and the University of Hawaii.
The study, led by Sean Vitousek, a engineering professor at the University of Illinois at Chicago, projects increases in flooding for Pacific islands, parts of Southeast Asia and coastlines along India, Africa and South America in the years and decades ahead, before spreading to engulf nearly the entire tropical region.
Alarming projections by Climate Central, a U.S.-based climate change science and advocacy group, show that approximately one million South Africans live in areas that will be inundated by rising seas as the climate warms, unless carbon emissions are cut steeply by the year 2100.
A World Bank study published in March identified coastal areas with low elevation, and assessed the consequences of continued sea-level rise for 84 developing countries, using satellite maps of the world overlaid with data on population growth.
Including 12 Southeast Asian nations: Brunei, Cambodia, China, Indonesia, D.P.R Korea, Republic of Korea, Malaysia, Myanmar, Papua New Guinea, Philippines, Thailand and Vietnam – the World Bank study found that the impact of sea-level rise will be particularly severe for this region.
A one-meter rise may displace some 37 million people, the World Bank concluded. The number of vulnerable people would increase to 60 million with a two-meter rise. A three-meter rise can impact 90 million people, nearly equivalent to the population of Vietnam, the fourth most populated country in East Asia.
China and Indonesia are the two countries most vulnerable to permanent inundation.
In March, China’s oceanic authority called for measures to cope with rising sea levels.
A report released by the State Oceanic Administration (SOA) said that the average sea level along China’s coast in 2017 was 58 mm (2.28 inches) higher than the average level between 1993 and 2011.
Over the past six years, the sea level along China’s coast has remained high compared with the previous 24 years.
The situation is the result of climate change and global warming, which have increased the temperature of China’s coastal regions and the ocean, according to the SOA report.
Rising sea levels will increase the area inundated by sea water, aggravate marine disasters, and harm the ecosystem, Chen Zhi, an SOA official, told the state-run Xinhua news agency in March.
The report said China’s ability to prevent and respond to disasters should be improved. The layout of coastal cities and infrastructure planning should take the rising sea levels into account, and emergency shelters and warehouses for disaster relief supplies should be located a safe distance from high-risk areas.
The SOA report advises that China’s coastal cities should verify the flood protection ability and upgrade design standards for important infrastructure projects in the Yangtze River Delta, the Pearl River Delta, and the northern coastal area of Bohai, near Beijing.
The report calls for protecting ecological resources, including coastal mangroves and wetlands.
The management of coastal water resources must be strengthened, the SOA advised, saying that the overexploitation of groundwater and land subsidence in coastal regions should be controlled in order to reduce harm from salt tides, sea water encroachment, and soil salinization.
China’s State Oceanic Administration report proposes pushing forward international cooperation in global marine governance, such as observation and prediction, risk assessment, and the response to rising sea levels.
One response that promotes safety, as Duke Kahanamoku said, “Never turn your back on the ocean.”
Featured Image: Wave breaks on the coast of Ireland, September 29, 2013 (Photo by John Twohig) Creative Commons license via Flickr