News / Science & Technology

Scientists Say Global Warming Affects Marine Life

Global warming and changing ocean chemistry affect marine nutrients and marine life
Global warming and changing ocean chemistry affect marine nutrients and marine life

In Narragansett Bay, Rhode Island, winter flounder no longer reproduce at the rate they used to.  Nutrients that once supported a rich marine life are less abundant.  And the water is warmer. It suffers from overfishing and shows signs of toxic chemicals banned 50 years ago. In short, say scientists at the University of Rhode Island, Narragansett Bay is typical of other coastal areas around the world. 

Reinner Lohmann teaches a course in marine pollution at the University of Rhode Island. He studies organic pollutants in Narragansett Bay; specifically, the chemical contents in sediment where small organisms feed and are the start of the marine food chain. He has found hundreds of pollutants including the pesticide DDT that was banned in the United States 40 years ago. "They may be stored in the sediments, but on a nice stormy day the sediments swell up and the compounds get released back into the water and can be taken back by fish," he explained.

Lohmann says every few years the U.S. Environmental Protection Agency checks on the contaminants in fish tissue.  Based on that data, government scientists establish safe eating guidelines for different fish.

The government fish advisories are based on the risk of cancer if you eat fish every day.  Lohmann says humans can take 20 to 30 years to eliminate the toxics they consume when they eat contaminated fish.  And long-term exposure to contaminants and the transfer of toxics from mother to child are major scientific concerns.

"We can detect these contaminants virtually everywhere," Lohmann said. "We have done studies in the Atlantic, the Arctic, in the Pacific -- they are everywhere."

Other researchers at the University of Rhode Island are studying the effects of warming water temperatures.

"One degree, it seems like nothing. But if you think back to the last glacial maximum (when the glaciers were at their thickest and the sea levels at their lowest), the change in temperature from that time until now is only five degrees celsius, or 10 degrees fahrenheit," Candace Oviatt said. Oviatt has studied the bay for more than 40 years. "So one degree is huge and we have seen huge changes on the bay as consequences of that."

Oviatt points to an 80 percent increase in rain storms.  This April, large areas of Rhode Island were flooded, overwhelming several water treatment plants.  Raw sewage, fertilizers and urban pollution ran freely into the bay.

"There is a lot of climate effects. One of the ones we experienced this week was this huge rain storm when we got eight inches [20.3 cm] of rain in three days," Oviatt said.

She adds that warmer temperatures in the bay and more rain water trigger a chain reaction of low oxygen and high levels of nutrients in the water, killing many organisms. "The winter flounder used to lay their eggs during the winter time because there are no predators, but if we heat up the bay waters, then those predators become active and they eat the eggs and the young juvenile winter flounder," she said.

Oviatt says overfishing and warmer waters have reduced the number of winter flounder by 75 percent.  That's led to an end to commercial flounder fishing, and a two-fish limit on recreational anglers.

Yet despite the strains on Narragansett Bay, another University of Rhode Island researcher, Scott Nixon, says the bay is in better shape now than 50 years ago when metals, oils and waste often were thrown directly into the ocean. Now there are other concerns. "I think most coastal ecologists would probably say the most pervasive, chronic, widespread problem is nutrient pollution: nitrogen and phosphorus pollution that comes from agricultures," he said.

Nixon said he hopes developing countries learn from our mistakes and stop polluting their coastal areas before more damage occurs.

You May Like

Disappointing Report on China's Economy Shakes Markets

In London and New York shares lost 3 percent, while Paris and Germany dropped around 2.4 percent More

DRC Tries Mega-Farms to Feed Population

Park at Boukanga Lonzo currently has 5,000 hectares under cultivation, crops stretching as far as eye can see, and is start of ambitious large-scale agriculture plan More

Video War, Drought Threaten Iraq's Marshlands

Areas are spawning ground for Gulf fisheries, a resting place for migrating wildfowl, source of livelihood for fishermen and herders who have called the marshes home for generations More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Nobel Prize Winner Malala Talks to VOAi
X
August 31, 2015 2:17 AM
Nobel Peace Prize winner Malala Yousafzai met with VOA's Deewa service in Washington Sunday to talk about women’s rights and unveil a trailer for her new documentary. VOA's Katherine Gypson has more.
Video

Video Nobel Prize Winner Malala Talks to VOA

Nobel Peace Prize winner Malala Yousafzai met with VOA's Deewa service in Washington Sunday to talk about women’s rights and unveil a trailer for her new documentary. VOA's Katherine Gypson has more.
Video

Video War, Drought Threaten Iraq's Marshlands

Iraq's southern wetlands are in crisis. These areas are the spawning ground for Gulf fisheries, a resting place for migrating wildfowl, and source of livelihood for fishermen and herders. Faith Lapidus has more.
Video

Video Colombians Flee Venezuela as Border Crisis Escalates

Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Rebuilding New Orleans' Music Scene

Ten years after Hurricane Katrina inundated New Orleans, threatening to wash away its vibrant musical heritage along with its neighborhoods, the beat goes on. As Bronwyn Benito and Faith Lapidus report, a Musicians' Village is preserving the city's unique sound.
Video

Video In Russia, Auto Industry in Tailspin

Industry insiders say country relies too heavily on imports as inflation cuts too many consumers out of the market. Daniel Schearf has more from Moscow.
Video

Video Scientist Calls Use of Fetal Tissue in Medical Research Essential

An anti-abortion group responsible for secret recordings of workers at a women's health care organization claims the workers shown are offering baby parts for sale, a charge the organization strongly denies. While the selling of fetal tissue is against the law in the United States, abortion and the use of donated fetal tissue for medical research are both legal. VOA’s Julie Taboh reports.
Video

Video Next to Iran, Climate at Forefront of Obama Agenda

President Barack Obama this week announced new initiatives aimed at making it easier for Americans to access renewable energy sources such as solar and wind. Obama is not slowing down when it comes to pushing through climate change measures, an issue he says is the greatest threat to the country’s national security. VOA correspondent Aru Pande has more from the White House.
Video

Video Arctic Draws International Competition for Oil

A new geopolitical “Great Game” is underway in earth’s northernmost region, the Arctic, where Russia has claimed a large area for resource development and President Barack Obama recently approved Shell Oil Company’s test-drilling project in an area under U.S. control. Greg Flakus reports.
Video

Video Philippine Maritime Police: Chinese Fishermen a Threat to Country’s Security

China and the Philippines both claim maritime rights in the South China Sea.  That includes the right to fish in those waters. Jason Strother reports on how the Philippines is catching Chinese nationals it says are illegal poachers. He has the story from Palawan province.
Video

Video China's Spratly Island Building Said to Light Up the Night 'Like A City'

Southeast Asian countries claim China has illegally seized territory in the Spratly islands. It is especially a concern for a Philippine mayor who says Beijing is occupying parts of his municipality. Jason Strother reports from the capital of Palawan province, Puerto Princesa.
Video

Video Ages-old Ice Reveals Secrets of Climate Change

Ice caps don't just exist at the world's poles. There are also tropical ice caps, and the largest sits atop the Peruvian Andes - but it is melting, quickly, and may be gone within the next 20 years. George Putic reports scientists are now rushing to take samples to get at the valuable information about climate change locked in the ice.

VOA Blogs