Highest-ever winter water temperatures recordedAugust 07, 2009Tasmania's east coast is recording its highest-ever winter water temperatures of more than 13°C - up to 1.5°C above normal - due to a strengthening of an ocean current originating north of Australia. Satellites have given oceanographers an insight into a remarkable phenomenon - a significant extension of the Leeuwin Current curling around the southern tip of Tasmania and reaching as far north as St Helens. Remote sensing specialists at CSIRO's Wealth from Oceans Flagship have been observing the current in recent days using satellite data, and ocean measurements made near Maria Island on Tasmania's east coast. CSIRO oceanographers Katy Hill, David Griffin and George Cresswell study ocean behaviour in the Australian region. Dr Cresswell says that scientists use ocean observations from satellite, ocean instruments and research vessels - such as the Marine National Facility, RV Southern Surveyor - to track the currents but there are also other indicators such as tropical species reaching Tasmania. "It's important for us to monitor these changes in the ocean, as they can have consequences for marine ecosystems, fisheries, aquaculture, coastal communities and more," Dr Cresswell says. The Leeuwin Current forms north of Australia and flows right around the western half of the country, meeting its better known cousin, the East Australian Current (EAC), at Tasmania. The exact location of this meeting point varies both seasonally and from year-to-year, depending on how strongly each current is flowing. Oceanographers believe the EAC has gradually been getting stronger, and the Leeuwin Current weaker. Changes in the EAC are among the most significant in the global ocean, with a continuous record of monthly measurements one of Australian oceanography's most valuable indicators for climate and environmental monitoring. Observations of temperature, salinity and nutrients have been collected monthly just east of Maria Island since 1944, showing how the influence of both the EAC and Leeuwin Current systems varies in Tasmanian waters. As part of the Integrated Marine Observing System (IMOS), a National Reference Station mooring has been deployed at the same site, and data is now available online every 10 minutes. Monthly samples are taken by boat to measure nutrients, phytoplankton, and zooplankton (biomass and species composition). Satellite images indicate the surface water temperature over the continental shelf current is around 13 degrees, a degree or two warmer than at this time in recent years. The EAC has been a research focus for Katy Hill since 2005 as part of her PhD in the Quantitiative Marine Science program - a joint initiative of CSIRO and the University of Tasmania. The St Helens-based Chief Executive of the Tasmanian Rock Lobster Association, Rodney Treloggen, said he was not aware of any reports of Indian Ocean species but he said fishers were concerned at what he described as a "bad year" for the industry in the south-east and east coast. "We know the warmer waters have an impact but we're not sure how much," Mr Treloggen said. CSIRO |
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| Related Water Temperature Current Events and Water Temperature News Articles Cyclone Rene Slams Tonga, Moves Into Open Waters Tropical Cyclone Rene slammed Tonga early yesterday, February 15, with maximum sustained winds near 100 mph (160 kilometers). Earth's early ocean cooled more than a billion years earlier than thought: Stanford study The scalding-hot sea that supposedly covered the early Earth may in fact never have existed, according to a new study by Stanford University researchers who analyzed isotope ratios in 3.4 billion-year-old ocean floor rocks. Early life on Earth may have developed more quickly than thought The Earth's climate was far cooler - perhaps more than 50 degrees - billions of years ago, which could mean conditions for life all over the planet were more conducive than previously believed, according to a research team that includes a Texas A&M University expert who specializes in geobiology. New insight into predicting cholera epidemics in the Bengal Delta Cholera, an acute diarrheal disease caused by the bacterium Vibrio cholerae, has reemerged as a global killer. Outbreaks typically occur once a year in Africa and Latin America. But in Bangladesh the epidemics occur twice a year - in the spring and again in the fall. Robot fish could monitor water quality Nature inspires technology for an engineer and an ecologist teamed up at Michigan State University. They're developing robots that use advanced materials to swim like fish to probe underwater environments. Remotely Operated Vehicles and Satellite Tags Aid Turtle Studies Researchers are using a remotely operated vehicle (ROV) and satellite-linked data loggers to learn more about turtle behavior in commercial fishing areas and to develop new ways to avoid catching turtles in fishing gear. Salmon migration mystery explored on Idaho's Clearwater River Temperature differences and slow-moving water at the confluence of the Clearwater and Snake rivers in Idaho might delay the migration of threatened juvenile salmon and allow them to grow larger before reaching the Pacific Ocean. Small fluctuations in solar activity, large influence on the climate Our sun does not radiate evenly. The best known example of radiation fluctuations is the famous 11-year cycle of sun spots. Nobody denies its influence on the natural climate variability, but climate models have, to-date, not been able to satisfactorily reconstruct its impact on climate activity. Scientists Conduct Shark Survey off U.S. East Coast Sandbar, dusky and tiger sharks are among dozens of shark species living in the coastal waters off the U.S. East Coast. Little is known about many of the species, but a survey begun nearly 25 years ago is helping scientists and fishery resource managers to monitor shark populations and their role in marine ecosystems. Small fossils provide key clues for interpreting environmental changes The Micropalaeontology team at the Department of Stratigraphy and Palaeontology at the University of the Basque Country (UPV/EHU) is working on the study of microfossils under the direction of Mr Julio Rodríguez Lázaro. More Water Temperature Current Events and Water Temperature News Articles |
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