Fact check: Photos show no change in sea level over 99 years but don’t disprove climate change

The claim: Photos prove no sea level rise, climate change is a hoax

Just a few days before Earth Day 2021, a Facebook post claimed to show climate change is a hoax based on two photos taken a century apart.

The post reads, “99 years of sea level rise — Palm Beach Sydney,” and  includes images labeled as being from 1917 and  2016. They show the water level at a similar point both years.

“For years they called it Global Warming. But they were proven over and over that no such thing is happening,” says the April 19 post, which was shared thousands of times in various forms. “Then they started calling it Climate Change. Again it is a hoax.”

But the post ignores a basic element of how oceans work: tides.

USA TODAY reached out to the poster for further comment.

The origin of the photos

The images depict a strip of land with water on both sides. 

A similar black-and-white image was published in a The Daily Telegraph article with the caption: “Palm Beach from Barrenjoey in the early 1900s.”

A Google search of the color image indicates it is Palm Beach, one of the northern beaches in Sydney. USA TODAY did not find an exact date when it was taken.

However, the images do not reveal if a sea level change occurred because tides rise and fall. How similar the level is between pictures taken years or decades apart depends on what time of day each picture was taken. 

According to National Geographic:

  • Along a smooth, wide beach, the water can spread over a large area and the tidal range may be around a few centimeters.
  • In a confined area, such as a narrow, rocky inlet or bay, the tidal range could be several yards.
  • The lowest tides are found in enclosed seas like the Mediterranean or the Baltic. They rise about a foot.

The post “does not indicate if they were taken at the same time of the tidal cycle,” said Jayantha T. Obeysekera, director of the Sea Level Solutions Center at Florida International University.

Sea levels in photos don’t represent the rest of the world

The two images from Sydney represent only the situation in that area and not in the rest of the world, said Shimon Wdowinski, an Earth and environment professor at Florida International University, who researches climate change and sea levels. 

Sydney experiences a very slow rate of sea level rise: less than 1 millimeter/year, according to a National Oceanic and Atmospheric Administration analysis. Based on an article from The Australian, sea level rose in Sydney roughly about 2 1/2 inches in the past 100 years. 

This increase in sea level doesn’t have a visible impact on hill/rocky topography in the pictures. But it also doesn’t prove any broader point about climate change.

“They provide no evidence on climate change. Thus, the claim that ‘climate change is hoax’ has no logical connection to the pictures,” said Wdowinski.

And globally, sea levels are rising.

In the last century, the sea level rose about 8-9 inches, according to NOAA. The rate of sea level rise is accelerating yearly and has more than doubled from 0.06 inches per year throughout most of the 20th century to 0.14 inches per year from 2006 to 2015.

The rise is mostly due to a combination of melting water from glaciers and ice sheets, as well as the expansion of seawater as it gets warmer, according to NOAA.

“Sea level rise is not uniform around the globe. There are regional and local processes that affect the rate of sea level rise in each location,” Wdowinski said.

Our rating: False

The claim that two images show no sea level rise and therefore climate change is a hoax is FALSE, based on our research. Sea levels have risen minimally in Sydney, but they are rising globally, and climate change is one of the reasons, experts say.

Our fact-checking sources:

  • Earth Day website, accessed April 22
  • Facebook post, April 19
  • iStock by Getty Images, Palm Beach photo
  • National Geographic, June 23, 2011, “Cause and Effect: Tides”
  • The Daily Telegraph, Dec.19 2014, “The thin strip of sand the binds Barrenjoey Head to the mainland”
  • NASA, Global Climate Change, accessed on April 22
  • NOAA Climate.gov, Jan. 25, 2021, Climate Change: Global Sea Level
  • The Australian, “Tide turns on sea-level alarmists”
  • USA TODAY interview with Shimon Wdowinski, April 22
  • USA TODAY interview with Jayantha T. Obeysekera, April 22

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