Abu Dhabi coastline could retreat by year 2100 due to rising sea levels

Rising sea levels could cause Abu Dhabi’s coastline to retreat by several kilometres by the year 2100, a study has predicted.

Researchers have forecast that the climate change-induced sea level changes, and the knock-on effects on the ecology of the coastline, will cause the shoreline to retreat by between 2.26km and 3.81km this century.

While many of the emirate’s built-up areas may not be flooded because they sit on land that was elevated during the building process, other coastal regions could be significantly affected.

The first author of the study, Dr Stephen Lokier, an associate professor at the Petroleum Institute Abu Dhabi, which is part of Khalifa University of Science and Technology, said measurements found that the shoreline retreat taking place was greater than expected given how fast the sea level is rising.

“When we started looking at what was happening we were genuinely surprised,” he said.

Sea levels around the world are rising by about 3.2 millimetres per year, which would be expected to cause the shoreline to retreat by about 2.5 metres annually; however, the actual retreat observed is between 10 and 29 m per year.

Shoreline retreat has been increased by a process called “dynamic flooding”, in which the effect of the rise in sea level is multiplied because it increases erosion by, for example, changing the mangroves and the “mats” of microorganisms that line much of the coast.

Published in the journal Geomorphology, the study warns that the retreat of the shoreline "will threaten existing coastal infrastructure".

“You can elevate the coastline where you have infrastructure. If you don’t do it for the whole coastline, this process, this flooding, could isolate these areas,” said Dr Lokier.

“The other concern is that as sea level rises, you have coastal defences that may be one or two metres above the current sea level, but the increase in the energy because of the rising sea level hasn’t always been considered.”

The other authors of the study, entitled Implications of sea-level rise in a modern carbonate ramp setting, are Wesley Court and Dr Andreas Paul, who were both at the Petroleum Institute when the work was carried out, and Dr Takumi Onuma of JGI, a Japanese surveying company.

In a statement, the Environment Agency – Abu Dhabi said that it had carried out a number of studies on climate change, including one focused on sea level rise and another on its impact.

The agency said there were “limitations” on predicting sea level rise because of “large uncertainties over the extent of melting in the Greenland and Antarctic ice sheets”, adding that UN Intergovernmental Panel on Climate Change (IPCC) reports had produced “a wide range of projections.

“It is difficult to state with certainty what the actual level of sea level rise in 2100 is likely to be, but it is certain that some will occur,” the agency said.

Tidal gauges have been installed at different locations in Abu Dhabi to measure sea level changes, but the agency said the absence of long-term recording of sea level change and other measurements “make it challenging to model SLR impacts” as multiple factors affect the amount of flooding and erosion damage.

The agency said that Plan Abu Dhabi 2030 states that because of potential sea level rises, “all new waterfront development should be planning for higher water levels at their edge”.

Abu Dhabi’s development code notes that seawalls may be required to protect the land from the sea or prevent faster shoreline erosion.

The agency said that Plan Maritime 2030 notes that Abu Dhabi has 760km of coastline and that 68 per cent of the emirate’s economy, or Dh640 billion, comes from “the coastal zone”. Also, 900,000 people, or 42 per cent of the population, live in the emirate’s coastal zone.

According to Plan Maritime 2030, Abu Dhabi has 760 km of coastline, including 216 islands. “These factors could potentially be negatively impacted in case of sea level rise caused by climate change,” the agency said.

____________

Read more:

Tens of thousands of mangroves to be planted across the UAE

Marine conservation group launches in Middle East

UAE mangroves the largest in the Gulf, study finds

____________

Environmental campaigners meanwhile said the research highlighted the need for action to combat climate change as well as measures to mitigate its effects.

Julien Jreissati, Arab world campaigner at Greenpeace Mediterranean, said the study was “yet another warning signal that global action to combat climate change should be significantly ramped up”, with countries needing to cut greenhouse gas emissions and focus on renewable energy technology.

“Sea level rise along with desertification and extreme heat are direct consequences of climate change and will render daily life in the UAE very challenging in the near future if the fight against climate change is not seriously ramped up at a local, regional and national level,” he said.

He said the UAE “should lead by example” and transition to 100 per cent renewable energy and “decarbonise their transport sector, which currently almost exclusively relies on petrol”.

“The UAE needs as well to take the appropriate adaptation measures such as safeguarding and boosting their mangroves population, which would provide a good barrier against sea level rise and erosion as well as developing their infrastructure to adapt to the new conditions associated with climate change,” he said.