Findings of a new study have revealed that the Earth's oceans are warming far faster than scientists previously believed.
Rate Of Ocean Warming Nearly Doubled
The research, which was published in the journal Science Advances on Friday, March 10, and used data from thousands of robotic floats that measured water salinity and temperature, showed that the rate of ocean warming has nearly doubled since 1994 when compared with that which occurred in earlier decades.
Study researcher Tim Boyer, from NOAA's Ocean Climate Laboratory, and colleagues found that between 1960 and 2015, ocean warming worldwide was 13 percent greater than estimates made by the Intergovernmental Panel on Climate Change or IPCC. The study likewise revealed that the warming started to spread deeper into the ocean.
"OHC [ocean heat content] has increased fairly steadily and, since 1990, has increasingly involved deeper layers of the ocean," the researchers wrote. "All ocean basins examined have experienced significant warming since 1998, with the greatest warming in the southern oceans, the tropical/subtropical Pacific Ocean, and the tropical/subtropical Atlantic Ocean."
Rising Sea Level
The findings of the new study provide a grimmer outlook for consequences associated with warmer ocean water. The IPCC previously estimated that ocean warming can be blamed for 30 percent to 40 percent of sea level rise but based on the results of the new research, the figure would be more like 50 percent.
Increased water temperatures can cause frozen bodies such as glaciers to melt resulting in increased volumes of water in the oceans. The rise in sea levels, however, brings with it unwanted risks such as flooding and potentials for storm surges. People who live in coastal areas are particularly at risk.
A 2016 study has revealed that a sea level rise of 3 feet to 6 feet by the year 2100 may expose 13 million people in the United States to flooding. Even with a minimum rise of just 3 feet, researchers estimated that over 4.2 million people who live in coastal areas in the United States could still be affected.
Warming ocean waters poses risk to marine life as well. Coral bleaching, for instance, which is caused by warming water temperatures, has already resulted in up to 70 percent of corals dying off in some areas.
Due to rising temperatures, a new climate model suggested that 99 percent of the coral reefs worldwide could be on track to severe annual bleaching.
Coral bleaching has crucial environmental and economic impact. Coral reefs provide food and income to hundreds of millions of people generating about $375 billion per year from tourism, fisheries, and coastal protection. Coral reefs are also home to at least a quarter of all marine life, which means their loss could have devastating impact on creatures that thrive in the sea.
"Bleaching that takes place every year will invariably cause major changes in the ecological function of coral reef ecosystems," said Ruben van Hooidonk, from the University of Miami. "Further, annual bleaching will greatly reduce the capacity of coral reefs to provide goods and services, such as fisheries and coastal protection, to human communities."