The NASA-managed Sea-viewing Wide Field-of-view Sensor (SeaWiFS) instrument settled into orbit around Earth in 1997 and took its first measurements of ocean color. A decade later, the satellite's data has proved instrumental in countless applications and helped researchers paint a picture of a changing climate. NASA recognized the satellite's tenth anniversary September 19 with briefings at the Goddard Space Flight Center in Greenbelt, Md.
NASA and GeoEye's SeaWiFS instrument has given researchers the first global look at ocean biological productivity. Its data have applications for understanding and monitoring the impacts of climate change, setting pollution standards, and sustaining coastal economies that depend on tourism and fisheries.
"SeaWiFS allows us to observe ocean changes and the mechanisms linking ocean physics and biology, and that's important for our ability to predict the future health of the oceans in a changing climate," said Gene Carl Feldman, SeaWiFS project manager at Goddard.
Researchers used SeaWiFS data to identify factors controlling the unusual timing of the 2005 phytoplankton bloom in the California Current System that led to the die-off of Oregon coast seabirds. The blooming tiny microscopic plants are key indicators of ocean health, form the base of marine food webs, and absorb carbon dioxide -- a major greenhouse gas -- from Earth's atmosphere.
"Long-term observations of the California coast and other sensitive regions is essential to understanding how changing global climate impacted ecosystems in the past, and how it may do so in the future," said Stephanie Henson of the University of Maine, lead author of a study published last month in the American Geophysical Union's "Journal of Geophysical Research -- Oceans." "This type of large-scale, long-term monitoring can only be achieved using satellite instrumentation," she added.
The SeaWiFS instrument orbits Earth fourteen times a day, measuring visible light over every area of cloud-free land and ocean once every 48 hours. The result is a map of Earth with colors spanning the spectrum of visible light. Variations in the color of the ocean, particularly in shades of blue and green, allow researchers to determine how the numbers of the single-celled plants called phytoplankton are distributed in the oceans over space and time.
In other research, Mike Behrenfeld of Oregon State University, Corvallis, Ore., and colleagues were the first to use SeaWiFS to quantify biological changes in the oceans as a response to El Niño, which they described in a landmark 2001 study in Science.
"The 2001 study is significant because it marked the first time that global productivity was measured from a single sensor," said Paula Bontempi, program manager for the Biology and Biogeochemistry Research Program at NASA Headquarters in Washington. "The simplicity of SeaWiFS -- a single sensor designed only to measure ocean color -- has made it the gold standard for all ocean color monitoring instruments."
More recently, Zhiqiang Chen and colleagues at the University of South Florida, St. Petersburg, showed that SeaWiFS data have direct application for state and federal regulators looking to better define water quality standards. The team reported in "Remote Sensing of Environment" that instead of relying on the infrequent measurements collected from ships or buoys, SeaWiFS data can be used to monitor coastal water quality almost daily, providing managers with a more frequent and complete picture of changes over time.
SeaWiFS has revolutionized our understanding of the ocean's response to environmental change. Here's one example: over the last ten years, the instrument has gathered daily global bio-productivity readings. When coupled with daily sea surface temperature readings over the same time span, we immediately see a relationship between temperature and productivity.
Beyond the realm of ocean observations, however, SeaWiFS has "revolutionized the way people do research," Feldman said. SeaWiFS was one of the first missions to open up data access online to researchers, students and educators around the world. The mission was able to capitalize on advances in data processing and storage technologies and ride the crest of the World Wide Web's growth from its beginning.
When the SeaWiFS program launched in 1997, the goal was to place a sensor in space capable of routinely monitoring ocean color to better understand the interplay between the ocean and atmosphere and most importantly, the ocean's role in the global carbon cycle. A decade later, Feldman said, "SeaWiFS has exceeded everyone's expectations."
Adapted from materials provided by NASA/Goddard Space Flight Center.
2007年10月19日星期五
Deep-sea Scientific Drilling Program To Study Volatile Earthquake Zone Launched
The Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) gets underway September 21, with the Japanese drilling vessel Chikyu departing from Shingu Port with scientists aboard, all ready to log, drill, sample, and install monitoring instrumentation in one of the most active earthquake zones on Earth.
The vessel's launch starts the first of a series of scientific drilling expeditions that will retrieve geological samples and provide scientific data from the Nankai Trough fault zone for the first time. Situated off Japan's southwest coast, the Nankai Trough has reliably generated large-scale earthquakes and tsunamis for millions of years, including historic earthquakes in 1944 and 1946, which measured 8.1 and 8.3, respectively, on the Richter scale.
The NanTroSEIZE expeditions are supported by the Integrated Ocean Drilling Program, a marine research initiative jointly funded by Japan, the United States, a consortium of European countries, the People's Republic of China, and South Korea.
NanTroSEIZE scientists are prepared to drill deeply into the Earth to observe earthquake mechanisms in a well-known subduction zone. The process of subduction occurs when tectonic plates collide and one plate slides beneath another. Geological samples will be collected from the subduction zone, so that IODP scientists can analyze them and study the frictional properties of the rock.
Later, sensors are to be installed deep beneath the sea floor- in the seismogenic fault zone-to monitor development of earthquakes at close range. These sensors and data collected from cored samples are expected to yield new insights into naturally occurring processes responsible for earthquakes. IODP scientists anticipate that the new data also will help them understand water motion and how water affects subduction zones.
Ocean Drilling Program Director James F. Allan of the U.S. National Science Foundation (NSF) characterized the first NanTroSEIZE expedition as an important milestone. "NSF welcomes the beginning of a new tomorrow, where the Chikyu enables us to explore the origins of devastating earthquakes at their source, study Earth history through coring of unstable, thick sediment sections, and investigate the fundamentals of ocean crust formation. These new capabilities," Allan notes, "complement those provided by the U.S. scientific ocean drilling vessel and European mission-specific platforms, which also support IODP scientific investigations, and that have investigated the subseafloor biosphere and Earth's dynamic climate with great success."
The full range of NanTroSEIZE investigations will occur in four stages:
Stage 1, now underway, calls for drilling and sampling at six drill sites to characterize the region's geology and provide geotechnical information for subsequent deep riser drilling (see Figure 1).
Stage 2 involves drilling the first of two deep holes, using Chikyu's unique riser drilling technology to target the mega-splay fault zone (where an array of faults occur) at ~3,500 meters below the seafloor.
Stage 3 focuses on 6,000-meter deep drilling into the seismogenic zone and across the plate interface into subducting crust.
Stage 4 includes installing long-term observatory systems in two ultra-deep boreholes.
During Stage 1, drill targets are
1) the incoming sediment of Shikoku Basin and the underlying oceanic crust,
2) the frontal thrust system at the toe of the accretionary wedge (where sediment is added to tectonic plates through frictional contact),
3) the mid-wedge multiple-fault system (mega-splays), and
4) two, approximately 1,000-meter deep holes at sites identified for later deep penetration into seismogenic zone faults.
The current Stage 1 expedition will continue until November 16. The following Stage 1 expedition will sail from Nov. 17-Dec. 19, 2007, with new scientist participation.
Logging While Drilling (LWD) investigations will occur at all Stage 1 drill sites. LWD operations consist of continuously drilling one or more holes at each site by drilling down at a controlled rate, with logging tools incorporated into the bottom-hole assembly, a relatively short distance (tens of meters) behind the drill bit. Log data are acquired very soon after the hole is cut, providing the best possible data quality. LWD operational and science data are crucial for optimizing subsequent Stage 1 expeditions and future drilling stages.
The current NanTroSEIZE expedition is led by Co-Chief Scientist Harold Tobin, a marine geologist on the faculty of University of Wisconsin-Madison, and Co-Chief Scientist Masa Kinoshita, a marine geophysicist at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), a leading research institution in Japan.
"A fundamental goal of the NanTroSEIZE expedition," says Dr. Tobin, "is to put long-term monitoring instruments down inside the earthquake fault, so we can look at the physics of the fault process. We will be able to determine whether earthquakes actually have precursory signalsþuthings that happen before the earthquakesþuwe can measure that will provide early warning systems for people on land."
Co-chief scientist Dr. Kinoshita explains that to people in Japan, earthquakes and tsunamis are serious matters. "Consequently, it is logical and relatively easy to excavate into the earthquake source to learn about its mechanism," he says. The NanTroSEIZE science party will excavate 6,000 meters below the 2,000-meter deep oceanic bottom to meet the expedition's scientific objectives.
Prior to its role in NanTroSEIZE, the Chikyu underwent a full schedule of systems integration testing near Shimokita Peninsula and in-situ testing of its drilling, coring, and navigation systems. Sea trials for the custom-built drilling vessel began in 2005 and concluded more than two years later. The Chikyu is the first riser-equipped scientific research vessel in the world.
Its high-tech laboratories are specifically designed for core retrieval, description, and analysis. Complex data sets are assembled onboard and entered into a vast IODP database. Daily and weekly logs are posted online from the ship for access by a global community of research scientists eager to glean news of these ground-breaking investigations.
Stage 1 NanTroSEIZE expeditions are managed by JAMSTEC's Center for Deep Earth Exploration (CDEX) on behalf of the Integrated Ocean Drilling Program (IODP), an international marine research program dedicated to advancing scientific understanding of Earth by monitoring and sampling subseafloor environments.
IODP has operated since 2003, extending the research legacies of the previous Ocean Drilling Program and the Deep Sea Drilling Project. IODP, led by the United States National Science Foundation (NSF) and Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT), currently has 21 member countries. Its Associate Members include ECORD (European Consortium for Ocean Research Drilling); China's Ministry of Science Technology; and the Republic of Korea.
Adapted from materials provided by Integrated Ocean Drilling Program Management International.
The vessel's launch starts the first of a series of scientific drilling expeditions that will retrieve geological samples and provide scientific data from the Nankai Trough fault zone for the first time. Situated off Japan's southwest coast, the Nankai Trough has reliably generated large-scale earthquakes and tsunamis for millions of years, including historic earthquakes in 1944 and 1946, which measured 8.1 and 8.3, respectively, on the Richter scale.
The NanTroSEIZE expeditions are supported by the Integrated Ocean Drilling Program, a marine research initiative jointly funded by Japan, the United States, a consortium of European countries, the People's Republic of China, and South Korea.
NanTroSEIZE scientists are prepared to drill deeply into the Earth to observe earthquake mechanisms in a well-known subduction zone. The process of subduction occurs when tectonic plates collide and one plate slides beneath another. Geological samples will be collected from the subduction zone, so that IODP scientists can analyze them and study the frictional properties of the rock.
Later, sensors are to be installed deep beneath the sea floor- in the seismogenic fault zone-to monitor development of earthquakes at close range. These sensors and data collected from cored samples are expected to yield new insights into naturally occurring processes responsible for earthquakes. IODP scientists anticipate that the new data also will help them understand water motion and how water affects subduction zones.
Ocean Drilling Program Director James F. Allan of the U.S. National Science Foundation (NSF) characterized the first NanTroSEIZE expedition as an important milestone. "NSF welcomes the beginning of a new tomorrow, where the Chikyu enables us to explore the origins of devastating earthquakes at their source, study Earth history through coring of unstable, thick sediment sections, and investigate the fundamentals of ocean crust formation. These new capabilities," Allan notes, "complement those provided by the U.S. scientific ocean drilling vessel and European mission-specific platforms, which also support IODP scientific investigations, and that have investigated the subseafloor biosphere and Earth's dynamic climate with great success."
The full range of NanTroSEIZE investigations will occur in four stages:
Stage 1, now underway, calls for drilling and sampling at six drill sites to characterize the region's geology and provide geotechnical information for subsequent deep riser drilling (see Figure 1).
Stage 2 involves drilling the first of two deep holes, using Chikyu's unique riser drilling technology to target the mega-splay fault zone (where an array of faults occur) at ~3,500 meters below the seafloor.
Stage 3 focuses on 6,000-meter deep drilling into the seismogenic zone and across the plate interface into subducting crust.
Stage 4 includes installing long-term observatory systems in two ultra-deep boreholes.
During Stage 1, drill targets are
1) the incoming sediment of Shikoku Basin and the underlying oceanic crust,
2) the frontal thrust system at the toe of the accretionary wedge (where sediment is added to tectonic plates through frictional contact),
3) the mid-wedge multiple-fault system (mega-splays), and
4) two, approximately 1,000-meter deep holes at sites identified for later deep penetration into seismogenic zone faults.
The current Stage 1 expedition will continue until November 16. The following Stage 1 expedition will sail from Nov. 17-Dec. 19, 2007, with new scientist participation.
Logging While Drilling (LWD) investigations will occur at all Stage 1 drill sites. LWD operations consist of continuously drilling one or more holes at each site by drilling down at a controlled rate, with logging tools incorporated into the bottom-hole assembly, a relatively short distance (tens of meters) behind the drill bit. Log data are acquired very soon after the hole is cut, providing the best possible data quality. LWD operational and science data are crucial for optimizing subsequent Stage 1 expeditions and future drilling stages.
The current NanTroSEIZE expedition is led by Co-Chief Scientist Harold Tobin, a marine geologist on the faculty of University of Wisconsin-Madison, and Co-Chief Scientist Masa Kinoshita, a marine geophysicist at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), a leading research institution in Japan.
"A fundamental goal of the NanTroSEIZE expedition," says Dr. Tobin, "is to put long-term monitoring instruments down inside the earthquake fault, so we can look at the physics of the fault process. We will be able to determine whether earthquakes actually have precursory signalsþuthings that happen before the earthquakesþuwe can measure that will provide early warning systems for people on land."
Co-chief scientist Dr. Kinoshita explains that to people in Japan, earthquakes and tsunamis are serious matters. "Consequently, it is logical and relatively easy to excavate into the earthquake source to learn about its mechanism," he says. The NanTroSEIZE science party will excavate 6,000 meters below the 2,000-meter deep oceanic bottom to meet the expedition's scientific objectives.
Prior to its role in NanTroSEIZE, the Chikyu underwent a full schedule of systems integration testing near Shimokita Peninsula and in-situ testing of its drilling, coring, and navigation systems. Sea trials for the custom-built drilling vessel began in 2005 and concluded more than two years later. The Chikyu is the first riser-equipped scientific research vessel in the world.
Its high-tech laboratories are specifically designed for core retrieval, description, and analysis. Complex data sets are assembled onboard and entered into a vast IODP database. Daily and weekly logs are posted online from the ship for access by a global community of research scientists eager to glean news of these ground-breaking investigations.
Stage 1 NanTroSEIZE expeditions are managed by JAMSTEC's Center for Deep Earth Exploration (CDEX) on behalf of the Integrated Ocean Drilling Program (IODP), an international marine research program dedicated to advancing scientific understanding of Earth by monitoring and sampling subseafloor environments.
IODP has operated since 2003, extending the research legacies of the previous Ocean Drilling Program and the Deep Sea Drilling Project. IODP, led by the United States National Science Foundation (NSF) and Japan's Ministry of Education, Culture, Sports, Science and Technology (MEXT), currently has 21 member countries. Its Associate Members include ECORD (European Consortium for Ocean Research Drilling); China's Ministry of Science Technology; and the Republic of Korea.
Adapted from materials provided by Integrated Ocean Drilling Program Management International.
Could Iron Fertilization Of Oceans Combat Global Warming?
Several times over the past century, scientists and environmental engineers have proposed spreading slurries of dissolved iron into the oceans in order to “fertilize” the waters and promote vast blooms of marine plants (phytoplankton). Phytoplankton consume carbon dioxide as they grow, and this growth can be stimulated in certain ocean basins by the addition of iron, a necessary micronutrient.
Though common on land, dissolved iron is often rare in the ocean. Some researchers and commercial interests have recently proposed to provide that missing nutrient on a large scale in order to create artificial blooms. Theory holds that if you make such blooms large enough, you could remove excess carbon dioxide from Earth’s atmosphere and carry it down into the deep ocean as organic matter (such as fecal pellets and dead plankton) sinks, thereby reducing the impact of greenhouse gases and global warming.
On September 26-27, scientists at the Woods Hole Oceanographic Institution (WHOI) will host an international, interdisciplinary conference on the proposed “iron fertilization” of the ocean as a means to combat rising concentrations of greenhouse gases in the atmosphere.
“There are many critical questions that require both better scientific understanding and an improved legal, economic, and political framework before iron fertilization can be considered either effective or appropriate,” said Ken Buesseler, a senior scientist in WHOI’s Marine Chemistry and Geochemistry Department and a participant in two iron fertilization experiments at sea. “The time is right to bring scientists, policymakers, and commercial interests together to inform each other and the public.”
Scientists took a serious interest in the idea in the late 1980s after oceanographer John Martin famously told colleagues: “Give me half a tanker of iron and I’ll give you the next ice age.” Iron fertilization has since been tested in at least a dozen experiments around the world.
The results have varied, but in general, iron fertilizers have been shown to promote plant growth in surface waters. However, many researchers remain skeptical about whether the process removes carbon dioxide from the atmosphere for the long term or just for a fleeting time. Ecological impacts from long-term, large-scale fertilization are also a concern.
The purpose of the Woods Hole conference is to bring researchers, policymakers, industrial interests, regulators, and environmentalists together to share their scientific observations and discuss the range of issues involved in altering the chemistry of the ocean. It is not intended as forum or referendum for specific projects and ventures.
In 20 hours of formal presentations and panel discussions over two days, participants will discuss:
Efficacy: Can iron fertilization work?
Research: What do we already know, and what could future studies, models, and experiments tell us?
Consequence: What will be the intended and unintended impacts?
Policy: What are the economic, social, and regulatory considerations?
The symposium—“Exploring Ocean Iron Fertilization: The Scientific, Economic, Legal, and Political Basis”-- is being hosted by Buesseler, Scott Doney, a senior scientist in the WHOI Marine Chemistry and Geochemistry Department, and Hauke Kite-Powell, a research specialist in the WHOI Marine Policy Center.
Support for the iron fertilization conference was provided by the Elisabeth and Henry Morss Jr. Colloquia Fund, the Cooperative Institute for Climate Research, the WHOI Marine Policy Center, the Ocean and Climate Change Institute, the Ocean Life Institute, and Woods Hole Sea Grant.
Adapted from materials provided by Woods Hole Oceanographic Institution.
Though common on land, dissolved iron is often rare in the ocean. Some researchers and commercial interests have recently proposed to provide that missing nutrient on a large scale in order to create artificial blooms. Theory holds that if you make such blooms large enough, you could remove excess carbon dioxide from Earth’s atmosphere and carry it down into the deep ocean as organic matter (such as fecal pellets and dead plankton) sinks, thereby reducing the impact of greenhouse gases and global warming.
On September 26-27, scientists at the Woods Hole Oceanographic Institution (WHOI) will host an international, interdisciplinary conference on the proposed “iron fertilization” of the ocean as a means to combat rising concentrations of greenhouse gases in the atmosphere.
“There are many critical questions that require both better scientific understanding and an improved legal, economic, and political framework before iron fertilization can be considered either effective or appropriate,” said Ken Buesseler, a senior scientist in WHOI’s Marine Chemistry and Geochemistry Department and a participant in two iron fertilization experiments at sea. “The time is right to bring scientists, policymakers, and commercial interests together to inform each other and the public.”
Scientists took a serious interest in the idea in the late 1980s after oceanographer John Martin famously told colleagues: “Give me half a tanker of iron and I’ll give you the next ice age.” Iron fertilization has since been tested in at least a dozen experiments around the world.
The results have varied, but in general, iron fertilizers have been shown to promote plant growth in surface waters. However, many researchers remain skeptical about whether the process removes carbon dioxide from the atmosphere for the long term or just for a fleeting time. Ecological impacts from long-term, large-scale fertilization are also a concern.
The purpose of the Woods Hole conference is to bring researchers, policymakers, industrial interests, regulators, and environmentalists together to share their scientific observations and discuss the range of issues involved in altering the chemistry of the ocean. It is not intended as forum or referendum for specific projects and ventures.
In 20 hours of formal presentations and panel discussions over two days, participants will discuss:
Efficacy: Can iron fertilization work?
Research: What do we already know, and what could future studies, models, and experiments tell us?
Consequence: What will be the intended and unintended impacts?
Policy: What are the economic, social, and regulatory considerations?
The symposium—“Exploring Ocean Iron Fertilization: The Scientific, Economic, Legal, and Political Basis”-- is being hosted by Buesseler, Scott Doney, a senior scientist in the WHOI Marine Chemistry and Geochemistry Department, and Hauke Kite-Powell, a research specialist in the WHOI Marine Policy Center.
Support for the iron fertilization conference was provided by the Elisabeth and Henry Morss Jr. Colloquia Fund, the Cooperative Institute for Climate Research, the WHOI Marine Policy Center, the Ocean and Climate Change Institute, the Ocean Life Institute, and Woods Hole Sea Grant.
Adapted from materials provided by Woods Hole Oceanographic Institution.
Forests Of Endangered Tropical Kelp Discovered
A research team led by San Jose State University and the University of California, Santa Barbara has discovered forests of a species of kelp previously thought endangered or extinct in deep waters near the Galapagos Islands.
The discovery has important implications for biodiversity and the resilience of tropical marine systems to climate change.
"The ecosystems that form in these cold, deep pockets beneath warm tropical waters look more like their cousins in California than the tropical reefs just 200 feet above," said co-author Brian Kinlan, a researcher with UC Santa Barbara's Marine Science Institute. "It is very similar to what we see when we climb a high mountain. For example, high alpine country in California looks more like Alaska."
Kinlan and Michael Graham, associate professor at SJSU, began by developing a mathematical model designed to predict likely habitat for the kelp, Eisenia galapagensis, based on information from satellites and oceanographic instruments on conditions including light, depth and nutrient availability. The premise of the model was developed by collaborator Louis Druehl, of the Bamfield Marine Science Centre, who surmised it was possible to create a predictive model for locating kelp forests rather than focusing on the limited details available from rare field observations.
The research team tested the model by traveling to the predicted habitat, where they searched for the kelp. Scuba divers -- including students from CSU Monterey Bay, CSU East Bay and UC Davis -- found the kelp forests from 40 to 200 feet below the surface, making the mission a success. The students conducted their surveys alongside the famed Amblyrhynchus christatus, the world's only seagoing iguanas.
The mission's success has three major implications. First, the World Conservation Union, which recently added Eisenia galapagensis to its global database of threatened species, may reconsider that action. Second, the model may find other marine life presumed endangered or rare but actually hidden beneath the ocean's surface.
The model does this by pinpointing unexpected places to search. In this case, the model correctly predicted that deep waters in the tropics could harbor kelp forests more commonly associated with temperate regions such as central California. The model identified nearly 10,000 square miles of similar unexpected cold spots in deep tropical waters worldwide.
The third implication of the research is that marine biodiversity may be more tolerant of climate change than presumed. Graham compares his team's kelp forests to the underwater hydrothermal vents discovered off South Africa in 1977. Scientists were surprised to find thriving ecosystems near those vents in water previously considered too deep and dark to harbor complex communities.
Graham theorizes the kelp forests his team discovered may reveal a similar wealth of plant and animal life. So while global warming may heat coral reefs and alter life there, marine communities may continue to thrive in kelp forests deep beneath the surface, where cooler nutrient-rich waters are less affected by surface warming.
The research paper describing the discovery is published in the Proceedings of the National Academy of Sciences.
Adapted from materials provided by University of California, Santa Barbara.
The discovery has important implications for biodiversity and the resilience of tropical marine systems to climate change.
"The ecosystems that form in these cold, deep pockets beneath warm tropical waters look more like their cousins in California than the tropical reefs just 200 feet above," said co-author Brian Kinlan, a researcher with UC Santa Barbara's Marine Science Institute. "It is very similar to what we see when we climb a high mountain. For example, high alpine country in California looks more like Alaska."
Kinlan and Michael Graham, associate professor at SJSU, began by developing a mathematical model designed to predict likely habitat for the kelp, Eisenia galapagensis, based on information from satellites and oceanographic instruments on conditions including light, depth and nutrient availability. The premise of the model was developed by collaborator Louis Druehl, of the Bamfield Marine Science Centre, who surmised it was possible to create a predictive model for locating kelp forests rather than focusing on the limited details available from rare field observations.
The research team tested the model by traveling to the predicted habitat, where they searched for the kelp. Scuba divers -- including students from CSU Monterey Bay, CSU East Bay and UC Davis -- found the kelp forests from 40 to 200 feet below the surface, making the mission a success. The students conducted their surveys alongside the famed Amblyrhynchus christatus, the world's only seagoing iguanas.
The mission's success has three major implications. First, the World Conservation Union, which recently added Eisenia galapagensis to its global database of threatened species, may reconsider that action. Second, the model may find other marine life presumed endangered or rare but actually hidden beneath the ocean's surface.
The model does this by pinpointing unexpected places to search. In this case, the model correctly predicted that deep waters in the tropics could harbor kelp forests more commonly associated with temperate regions such as central California. The model identified nearly 10,000 square miles of similar unexpected cold spots in deep tropical waters worldwide.
The third implication of the research is that marine biodiversity may be more tolerant of climate change than presumed. Graham compares his team's kelp forests to the underwater hydrothermal vents discovered off South Africa in 1977. Scientists were surprised to find thriving ecosystems near those vents in water previously considered too deep and dark to harbor complex communities.
Graham theorizes the kelp forests his team discovered may reveal a similar wealth of plant and animal life. So while global warming may heat coral reefs and alter life there, marine communities may continue to thrive in kelp forests deep beneath the surface, where cooler nutrient-rich waters are less affected by surface warming.
The research paper describing the discovery is published in the Proceedings of the National Academy of Sciences.
Adapted from materials provided by University of California, Santa Barbara.
hy Is The Ocean Salty?
The saltiness of the sea comes from dissolved minerals, especially sodium, chlorine, sulfur, calcium, magnesium, and potassium, says Galen McKinley, a UW-Madison professor of atmospheric and oceanic sciences.
Today’s ocean salt has ancient origins. As the earth formed, gases spewing from its interior released salt ions that reached the ocean via rainfall or land runoff.
Now, the ocean’s salinity is basically constant. “Ions aren’t being removed or supplied in an appreciable amount,” McKinley says. “The removal and sources that do exist are so small and the reservoir is so large that those ions just stay in the water.” For example, she says, “Each year, runoff from the land adds only 0.00005 percent of total ocean salts.”
In lakes, relatively rapid turnover of water and its dissolved salts keeps the water fresh – a water droplet and its ions will stay in Lake Superior for about 200 years, compared to roughly 100 to 200 million years in the ocean. “Even if you did have any accumulation of an ion in a lake, it would be washed out quickly,” McKinley explains.
Ocean salts, however, have no place to go. “The ions that were put there long ago have managed to stick around,” McKinley says. “There is geologic evidence that the saltiness of the water has been the way that it is for at least a billion years.”
Today’s ocean salt has ancient origins. As the earth formed, gases spewing from its interior released salt ions that reached the ocean via rainfall or land runoff.
Now, the ocean’s salinity is basically constant. “Ions aren’t being removed or supplied in an appreciable amount,” McKinley says. “The removal and sources that do exist are so small and the reservoir is so large that those ions just stay in the water.” For example, she says, “Each year, runoff from the land adds only 0.00005 percent of total ocean salts.”
In lakes, relatively rapid turnover of water and its dissolved salts keeps the water fresh – a water droplet and its ions will stay in Lake Superior for about 200 years, compared to roughly 100 to 200 million years in the ocean. “Even if you did have any accumulation of an ion in a lake, it would be washed out quickly,” McKinley explains.
Ocean salts, however, have no place to go. “The ions that were put there long ago have managed to stick around,” McKinley says. “There is geologic evidence that the saltiness of the water has been the way that it is for at least a billion years.”
Deep Sea Discoveries Off Canada's East Coast
Researchers from Fisheries and Oceans Canada and Memorial University of Newfoundland took part in an exciting survey of unexplored depths of the Atlantic Ocean during a three-week mission in July 2007. Deep water corals were a primary focus of the research. Researchers onboard the Canadian Coast Guard Ship Hudson surveyed deep water animal life off the coasts of Nova Scotia and Newfoundland using an underwater robot known as ROPOS (Remotely Operated Platform for Ocean Science). With ROPOS, they collected samples and images at depths of 2,500 metres; and transmitted live underwater video footage to researchers at various land locations.
The mission revealed that life in these waters is much more diverse than previously realized. Researchers captured over 3,000 high quality photographs that displayed this diversity, including an octopus with large fins near its eyes, known as "Dumbo," a potentially new species of scallop, and a single-celled organism previously unknown in this region.
Research based on the mission’s findings will continue for the next year at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia and its partner universities. The role of the newly discovered species in the marine food chain will be one of the prime areas of study; findings could also have implications for conservation efforts and medicine.
The mission revealed that life in these waters is much more diverse than previously realized. Researchers captured over 3,000 high quality photographs that displayed this diversity, including an octopus with large fins near its eyes, known as "Dumbo," a potentially new species of scallop, and a single-celled organism previously unknown in this region.
Research based on the mission’s findings will continue for the next year at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia and its partner universities. The role of the newly discovered species in the marine food chain will be one of the prime areas of study; findings could also have implications for conservation efforts and medicine.
Fishing Ban Protects Largest Coral Reef In The Philippines
Reef fish and other marine species can breathe easier with the introduction of a fishing ban around Apo Reef, the largest coral reef in the Philippines and the second largest contiguous reef in the world after the Great Barrier Reef.
Under the ban, all extractive activities, such as fishing, and coral collection and harvesting, will be completely forbidden.
“This ‘no-take’ zone will allow the reef and its residents ample time to recover from years of fishing,” stressed John Manul of WWF-Philippines.
The 27,469-hectare Apo Reef off the coast of Mindoro Island is surrounded by mangrove forest, which serves as a source of food, nursery and spawning ground of several coastal fish and marine species, including sharks, manta rays, sperm whales and several sea turtles.
In 1996, the reef was declared a national park, but enforcement proved lax and illegal fishing methods persisted.
The park was once one of the world’s premier diving destinations, but years of fishing — including by unsustainable fishing practices such as using dynamite and cyanide — took its toll.
“You would hear 25 to 30 dynamite blasts daily,” said Robert Duquil, a former protected area assistant superintendent. “The international diving community lost interest in the area and destructive activities prevailed.”
Adding to the reef’s troubles, the El Niño phenomenon in 1998 raised ocean temperatures, prompting a massive bleaching episode and the death of countless corals, and an explosion of coral-eating crown-of-thorns starfish.
“Unfortunately, Apo is plagued by millions of these starfish, probably due to a lack of natural predators like the giant triton, napoleon wrasse and harlequin shrimp,” said Gregg Yan of WWF-Philippines. “We hope that the ban will ensure protection of these predators and the many other reef species.”
WWF has been working towards sustainable coastal practices for the Apo Reef Natural Park since 2003. The marine park will be opened for tourists to help generate funds for its protection, as well as provide an alternative livelihood for hundreds of fishermen in the area.
Adapted from materials provided by World Wildlife Fund.
Under the ban, all extractive activities, such as fishing, and coral collection and harvesting, will be completely forbidden.
“This ‘no-take’ zone will allow the reef and its residents ample time to recover from years of fishing,” stressed John Manul of WWF-Philippines.
The 27,469-hectare Apo Reef off the coast of Mindoro Island is surrounded by mangrove forest, which serves as a source of food, nursery and spawning ground of several coastal fish and marine species, including sharks, manta rays, sperm whales and several sea turtles.
In 1996, the reef was declared a national park, but enforcement proved lax and illegal fishing methods persisted.
The park was once one of the world’s premier diving destinations, but years of fishing — including by unsustainable fishing practices such as using dynamite and cyanide — took its toll.
“You would hear 25 to 30 dynamite blasts daily,” said Robert Duquil, a former protected area assistant superintendent. “The international diving community lost interest in the area and destructive activities prevailed.”
Adding to the reef’s troubles, the El Niño phenomenon in 1998 raised ocean temperatures, prompting a massive bleaching episode and the death of countless corals, and an explosion of coral-eating crown-of-thorns starfish.
“Unfortunately, Apo is plagued by millions of these starfish, probably due to a lack of natural predators like the giant triton, napoleon wrasse and harlequin shrimp,” said Gregg Yan of WWF-Philippines. “We hope that the ban will ensure protection of these predators and the many other reef species.”
WWF has been working towards sustainable coastal practices for the Apo Reef Natural Park since 2003. The marine park will be opened for tourists to help generate funds for its protection, as well as provide an alternative livelihood for hundreds of fishermen in the area.
Adapted from materials provided by World Wildlife Fund.
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