Quantcast

Record-Warm Oceans: How Worried Should We Be?

Insights + Opinion
A sea turtle swims above a fragile coral reef in Wailea, Maui, Hawaii. M Swiet Productions / Moment / Getty Images

By Ilissa Ocko

The world's oceans are heating up. Scientists have found that 2018 was the hottest year ever recorded for our oceans, and that they are warming even faster than previously thought.

When documenting global warming trends, we often focus on air temperature. But the oceans actually absorb more than 90 percent of the excess heat trapped by human emissions of greenhouse gases. So if we really want to know how much our planet is warming up, we look to the oceans.


And what the oceans are telling us is alarming.

Using multiple measurement devices, scientists from across the globe found that the amount of heat in the upper part of the world's oceans in 2018 was the highest ever recorded since observations began in the 1950s. In fact, the past five years are the warmest years on record and the increase in ocean heat has been accelerating since the 1990s.

Scientists also found that the oceans are warming faster than data previously published in a 2013 landmark report by the United Nations' Intergovernmental Panel on Climate Change.

Studies now show that in recent decades, the rate of warming in the upper ocean—the top 2,000 meter or 6,500 feet layer of the ocean—was about 40 percent higher than the earlier IPCC estimates showed. The new data, made possible by vast improvements to ocean heat records in recent years, is also consistent with model projections of ocean warming.

So how worried should we be?

Why Warmer Oceans Matter

Rising ocean temperatures are a major concern for societies and ecosystems across the globe. Hotter oceans lead to:

  • rising sea levels when water molecules expand from increasing temperatures, and then erode coasts, threaten infrastructure and contaminate freshwater with intruding saltwater.
  • heavier downpours and widespread flooding because more ocean water evaporates as temperatures increase, supplying the atmosphere with more moisture.
  • more destructive hurricanes because of the increased moisture in the air and higher sea levels that worsen storm surges.
  • dying coral reefs as the corals' colorful algae, their main food source, leave the corals due to heat stress. This bleaches corals of their vivid colors, causing them to starve, while affecting the survival of thousands of species that live in the reefs.
  • fish moving poleward because their current habitats are becoming too warm, disrupting fisheries.

There Is Still Time

Recent scientific reports have concluded that our greenhouse gas emissions so far have not yet committed us to future warming levels that can cause catastrophic climate impacts. That is great news.

There are, in fact, countless reasons to feel hopeful. Numerous countries are reducing greenhouse gas emissions while growing their economies. Renewable energy sources are increasingly more affordable. And new technologies, such as carbon dioxide removal, are emerging.

Oceans are warning us, and we need to act now. As disconcerting as this oceans news has been, there's still time.

Ilissa Ocko is a climate scientist at Environmental Defense Fund.

Show Comments ()

EcoWatch Daily Newsletter

Aerial view of the explosion site of a chemical factory on March 22 in Yancheng, Jiangsu Province of China. Caixin Media / VCG / Getty Images)

At least 47 people have died in an explosion at a plant in Yancheng, China Thursday run by a chemical company with a history of environmental violations, Sky News reported.

Read More Show Less
A fishmonger in Elmina, a fishing port in the Central Region of Ghana. Environmental Justice Foundation

By Daisy Brickhill

Each morning, men living in fishing communities along Ghana's coastline push off in search of the day's catch. But when the boats come back to shore, it's the women who take over.

Read More Show Less
Sponsored
Pexels

By Sam Nickerson

Links between excess sugar in your diet and disease have been well-documented, but new research by Harvard's School of Public Health might make you even more wary of that next soda: it could increase your risk of an early death.

The study, published this week in the American Heart Association's journal Circulation, found that drinking one or two sugar-sweetened beverages (SSBs) each day — like sodas or sports drinks — increases risk of an early death by 14 percent.

Read More Show Less
Krystal B / Flickr

Tyson Foods is recalling approximately 69,093 pounds of frozen chicken strips because they may have been contaminated with pieces of metal, the U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS) announced Thursday.

The affected products were fully-cooked "Buffalo Style" and "Crispy" chicken strips with a "use by" date of Nov. 30, 2019 and an establishment number of "P-7221" on the back of the package.

"FSIS is concerned that some product may be in consumers' freezers," the recall notice said. "Consumers who have purchased these products are urged not to consume them. These products should be thrown away or returned to the place of purchase."

Read More Show Less
Pixabay

By Hrefna Palsdottir, MS

Cold cereals are an easy, convenient food.

Read More Show Less
Sponsored
A tractor spraying a field with pesticides in Orem, Utah. Aqua Mechanical / CC BY 2.0

Environmental exposure to pesticides, both before birth and during the first year of life, has been linked to an increased risk of developing autism spectrum disorder, according to the largest epidemiological study to date on the connection.

The study, published Wednesday in BMJ, found that pregnant women who lived within 2,000 meters (approximately 1.2 miles) of a highly-sprayed agricultural area in California had children who were 10 to 16 percent more likely to develop autism and 30 percent more likely to develop severe autism that impacted their intellectual ability. If the children were exposed to pesticides during their first year of life, the risk they would develop autism went up to 50 percent.

Read More Show Less
The ExxonMobil Torrance Refinery in Torrance, California. waltarrrr / Flickr

ExxonMobil could be the second company after Monsanto to lose lobbying access to members of European Parliament after it failed to turn up to a hearing Thursday into whether or not the oil giant knowingly spread false information about climate change.

The call to ban the company was submitted by Green Member of European Parliament (MEP) Molly Scott Cato and should be decided in a vote in late April, The Guardian reported.

Read More Show Less
Bernie Sanders holds his first presidential campaign rally at Brooklyn College on March 02 in Brooklyn, New York. Kena Betancur / VIEWpress / Corbis. Getty Images

Bernie Sanders has become the first contender in the crowded 2020 Democratic presidential primary field to pledge to offset all of the greenhouse gas emissions released by campaign travel, The Huffington Post reported Thursday.

Read More Show Less