Home | Contact ST  

Content on this page requires a newer version of Adobe Flash Player.

Get Adobe Flash player

Follow ST

Ocean Research

2018:  FEB

March 2017 Issue

Climate Adaptation
Lessons from Tambora

The largest volcanic eruption in recorded history occurred at Indonesia’s Mount Tambora just over 200 years ago. Karen Alexander at the University of Massachusetts Amherst and 11 other ecologists, scientists and historians used historical fish export data, weather readings, dam construction, town growth chronologies and other sources to discover Tambora’s effects on the Gulf of Maine’s complex human and natural system.

The 1815 eruption caused an extreme climate event in 1816 known as the “year without a summer” and as the “mackerel year”. As volcanic winter settled in the Northern Hemisphere, crops failed, livestock died, famine occurred and fisheries were affected. Historical events such as the War of 1812, human population growth, fish habitat obstruction due to dam building and changes in fishing gear might also have affected fisheries.

At the time, alewives were the “utility fish”, but in the winter of 1816, their populations shrunk. During this climate crisis, people couldn’t catch enough alewives to meet their needs, so they quickly turned to mackerel, the next abundant species on the coast. This demonstrates the possibility of climate adaptation using natural resources.

Carbon Monitoring
In Southern Ocean

Dr. Elizabeth Shadwick of the Virginia Institute of Marine Science has deployed a high-tech mooring beneath the waters around Antarctica to better understand ocean acidification in the polar regions. To date, knowledge of carbon dioxide levels in the Southern Ocean around Antarctica relies almost exclusively on data collected by research vessels and resupply ships during summer’s brief window of ice-free water. Shadwick’s mooring will extend this record year-round.

The mooring is anchored to the seafloor around 1,600 ft. deep and terminates about 60 ft. below the sea surface. Its sensors measure dissolved carbon dioxide, pH, temperature, salinity and dissolved oxygen.

The autonomous sensors will monitor the full annual cycle of carbon dioxide in Antarctica’s coastal waters for the first time. The mooring will be recovered in early May, when a second identical mooring will be deployed to be recovered the following December.

The Southern Ocean plays an important role in the global carbon cycle, so these data should lead to a better understanding of global climate change.

Jane Lubchenco Awarded
Public Welfare Medal

The National Academy of Sciences is honoring Oregon State University marine ecologist Jane Lubchenco with its most prestigious award, the Public Welfare Medal, which recognizes distinguished contributions in the application of science to the public good since 1914. The medal honors individuals “who have worked tirelessly to promote science for the benefit of humanity.” Past winners include Neil deGrasse Tyson, Bill and Melinda Gates, and Carl Sagan.

The academy is honoring Lubchenco for “successful efforts in bringing together the larger research community, its sponsors and the public policy community to focus on urgent issues related to global environmental change.”

The former administrator of NOAA and the first woman to serve in that role, Lubchenco just completed a two-year term with the State Department as the first U.S. Science Envoy for the Ocean.

Robotic System Monitors,
Predicts Toxic Algae

Toxic algal blooms that infect shellfish, make people sick and hurt the shellfish industry are happening more and more along the New England coast. MIT Sea Grant-funded researchers from Woods Hole Oceanographic Institution, the Virginia Institute of Marine Science and NOAA have developed a robotic system to monitor blooms of toxic algae in real time. This system comprises the submersible Imaging FlowCytobot that dives down to photograph algae where they emit their toxins and the Environmental Sampler Processer that directly measures how much toxin is around.

NOAA reported shellfish sale losses of $23 million in Maine and Massachusetts alone from a red tide bloom in 2005.

Wave Gliders Support
South Korea Fisheries

The Ministry of Oceans and Fisheries (MOF) in South Korea manages nearly 1,500 mi. of coastline along three seas. The MOF chose the Liquid Robotics Wave Glider, along with traditional oceanographic survey devices such as aerial drones and a research ship, to conduct a bathymetric survey near Ulleungdo Island in the East Sea. The MOF hopes to use the Wave Glider for a range of applications, including tsunami detections, seismic readings, monitoring marine life and maritime surveillance.

Meteorite Not the Cause
Of Marine Biodiversity

A massive meteorite bombardment was suspected to have played a role in the Great Ordovician Biodiversification Event (GOBE), an explosion in the diversity of marine life, by causing just the right amount of environmental disturbance to stimulate this event, but a new study rules this out. Anders Lindskog of Lund University and colleagues discovered that the start of the GOBE actually preceded the meteorite bombardment. The researchers came across a limestone bed with an exceptional amount of mineral zircon grains from right in the middle of the GOBE interval. It also contained many meteorites.

The zircon grains, which clearly stem from a volcanic eruption, allowed the opportunity to pinpoint the age of the meteorite-bearing rocks. The zircon date allowed refinement of the overall geologic time scale for the Ordovician time period. Another geologic clock that uses noble gasses found in meteorites made it possible to calculate when the meteorites were first ejected into space during the disruption of their parent asteroid. The calculations give 468 ± 0.3 million years; much more precise than the previously known 470 ± 6 million years.

Thus, the researchers concluded that the GOBE started well before the asteroid collision took place.

2018:  FEB

-back to top-

Sea Technology is read worldwide in more than 110 countries by management, engineers, scientists and technical personnel working in industry, government and educational research institutions. Readers are involved with oceanographic research, fisheries management, offshore oil and gas exploration and production, undersea defense including antisubmarine warfare, ocean mining and commercial diving.