A renowned oceanographer will visit the Maritime Aquarium at Norwalk on Thursday, Jan. 24, and she's not bringing good news.
Sylvia Earle, former chief scientist at the National Oceanic and Atmospheric Administration and National Geographic's first explorer-in-residence, said in an interview last week that the ocean's health is declining and that the decline will affect everyone.
"The ocean is in trouble; therefore, we're in trouble," she said.
The ocean, which covers 71 percent of the earth's surface, impacts weather, oxygen in the atmosphere and food grown on land because rain is the result of water evaporating from the ocean, Earle said.
"The ocean touches you with every breath you take and every drop of water you drink," she said. "Take away the ocean, and you've got a planet like Mars."
Problems with the ocean, Earle said, include increasing acidity and temperature, the loss of 50 percent of its coral reefs, which are the habitat for more than 1 million species, and loss of 90 percent of its big fish.
She said 20 percent of the oxygen in the atmosphere comes from one species of plankton in the ocean, so small that it wasn't discovered until 1986, and that it's vulnerable to increases in the ocean's acidity.
Marine life that have shells also are affected by increased acidity, she said.
According to NOAA's website, studies have shown that increased acidity in the ocean has "a dramatic effect on some calcifying species, including oysters, clams, sea urchins, shallow water corals, deep sea corals and calcareous plankton. When shelled organisms are at risk, the entire food web may also be at risk."
Earle attributed the ocean's increased acidity to excessive carbon dioxide in the atmosphere.
"Excess CO2 in the atmosphere enters the ocean," she said. "Plants in the ocean take up CO2 in the process of photosynthesis. When you get too much in the ocean, it becomes carbonic acid."
The ocean absorbs about a quarter of the carbon dioxide released into the atmosphere every year and the ocean's acidity has increased 30 percent since the Industrial Revolution, according to NOAA. Under business-as-usual emissions of CO2, the ocean's surface waters could be more acidic in 2100 than they've been in the past 20 million years.
Earle said the ocean has its own way of reducing acidity, but that takes place over long periods of time. As acidity increases, limestone deposits at the bottom of the ocean will break down, and the resulting calcium carbonate will reverse the trend, she said.
But, she added, "These are longterm geologic cycles. What's happening now is we can see the cause and it's not happening over thousands of years, it's happening over decades. We need to take measures that will slow the process."
The ocean's temperature also is rising and that can lead to an increased intensification of storms, Earle said.
The Ocean Health Index, which is based on scientists' assessments, puts the state of the ocean at 60 out of a possible 100, Earle said.
"I tell people sometimes I come from a different planet because the planet now is so different from the one I came from," Earle, 77, said.
Earle said one way to mitigate the trend toward acidity is to reduce the burning of fossil fuels, which puts CO2 into the atmosphere. She said burning oil, gas and coal over the last century produced prosperity for humans, but its greatest gift was knowledge gained through advances in technology, such as satellites and the ability to quickly share information.
"Now we can see what we couldn't see before," she said. "Now we know, and we also have the skill and intellect to move in another direction, but we just have to hurry or the consequences are not in our favor."
Advances in technology have also made it easier to find larger species in the ocean, and Earle said 90 percent of the big fish, such as sharks and tuna, have been taken.
"We just thought they'd come back no matter how many we took," she said.
Earle said humans should move toward alternative energy sources, though she said that would be difficult because civilization has become dependent on the burning of coal, oil and gas.
She said humans have begun to protect natural resources on land, such as watersheds and forests, and that it was time to extend that protection to the ocean.
"The ocean drives the way the world works," she said. "It's our life-support system. The ocean generates most of the oxygen, stabilizes temperature and is home to most life on earth. If we really want a planet that is favorable to us, we have to give back to the natural system that keeps us alive."
The biggest problem related to the ocean, Earle said, was apathy and ignorance of the role it plays on earth.
"If people don't know, they can't care," she said.
She said her talk Thursday will include reasons why people should care and how the ocean's health can be improved.
Jennifer Herring, president of the Maritime Aquarium at Norwalk, said in a statement that the Aquarium was "honored to welcome Dr. Earle back ... and to share her message with our community. It will be inspiring to hear from someone with such a vast knowledge about the marine environment, yet still such a deep enthusiasm and driving curiosity, and from someone who has such an impassioned concern for the marine environmen."
Earle said she became an oceanographer because her parents and teachers encouraged her curiosity as a child and she grew up near the ocean. She said her family went to the New Jersey shore on vacation when she was a child and then moved when she was 12 to Florida, where she "had the freedom to splash around in the Gulf of Mexico."
"Maybe it was just inevitable I fell in love with the ocean. I didn't have a choice," she said.
Earle said very little is known about the ocean and that James Cameron, the film director, recently became only the second person in history to descend to the deepest part of the ocean, which is seven miles below the surface. Earle, who holds the women's world record for deepest solo submersible dive and who has spent 7,000 hours underwater, said she sees something new every time she dives in the ocean.
Earle said a friend of hers explores what he calls "the twilight zone" -- from 300 to 500 feet deep in the ocean -- and discovers a dozen new species of marine life an hour.
"It's so easy to go to a place in the ocean no one has seen before," Earle said. "We've only seen 5 percent of the ocean, let alone explored it. It's out there for kids today to aspire to become explorers of this planet, the blue one.
"We're at the edge of the greatest era of exploration ever."
Earle is founder of Deep Ocean Exploration and Research, a marine consulting company involved in creating solutions to underwater exploration problems. She also heads the Sylvia Earle Alliance, which aims to increase public awareness and support for protected marine areas, and Mission Blue, a worldwide alliance whose goal is to restore and protect the ocean's health.
Earle believes humans can learn a lot about the universe not only by exploring outer space, but by exploring the ocean, though she added that going seven miles down is harder than going seven miles up.
"Unless you look at the stars and dive in the ocean, you forget that everything is kind of a miracle and we are all witnesses to this amazing opportunity to be a part of it," she said.
Tickets to Earle's talk at the Maritime Aquarium at Norwalk, which takes place at 7:30 p.m., Thursday, Jan. 24, are $35 ($30 for Aquarium members) and can be reserved online at www.maritimeaquarium.org, or by calling 203-852-0700, ext. 2206.