Weekly Ocean News

SPRING BREAK WEEK: 13-17 March 2017

This is Break Week for the Spring 2017 offering of the DataStreme Ocean course. This Weekly Ocean News contains new information items and historical data, but the Concept of the Week is repeated from Week 6.

Report from the Field:

Iowa City Press-Citizen

For Your Information

Biomixing in ocean motion -- If you would like information on recent findings that indicate marine organisms contribute to motion in the ocean, please read this week's Supplemental Information…In Greater Depth.

Ocean in the News

Eye on the tropics --- Organized tropical cyclone activity was confined to the South Indian Ocean basin during the last week as the end of astronomical spring in the Southern Hemisphere approaches. Three tropical cyclones were reported across the basin during last week.
Cyclone Enawo, the ninth named tropical cyclone of the 2016-17 season in the South Indian Ocean, traveled toward the west-southwest at the start of last week, making landfall along the eastern coast of Madagascar on Tuesday. Enawo, which had intensified to become major category 4 tropical cyclone on the Saffir-Simpson Scale before landfall, as maximum sustained surface winds reached at least 140 mph. After making landfall, Enawo turned toward the south and weakened, bringing heavy rains and strong winds to Madagascar. Over the next day Enawo traveled southward over the island before emerging off its southeast coast on Thursday as a tropical storm. As of last Friday, the remnants of Enawo were located approximately 530 miles to the northwest of St. Denis, Reunion. The NASA Hurricane Page has additional information and a satellite image on Cyclone Enawo.
At the start of last week the short-lived Tropical Storm Blanche traveled across the waters of the Joseph Bonaparte Gulf in the eastern section of the South Indian Ocean basin and made landfall along the Kimberly coast of Western Australia approximately 200 miles to the west-southwest of Darwin, Northern Territory of Australia. Additional information and satellite imagery for Tropical Storm Blanche are available on the NASA Hurricane Page.
The third tropical cyclone of last week developed last Wednesday approximately 580 miles to the south-southwest of Diego Garcia in the western sections of the South Indian Ocean basin. This short-lived system was identified as Tropical Storm 11S as it was the eleventh tropical cyclone of the 2016-17 season in that basin. Tropical Storm 11S traveled an erratic path, initially traveling toward the west-northwest, then to the east and finally toward the south before being torn apart by wind shear late Friday after slightly more than 48 hours after formation. At that time, this tropical storm was located approximately 800 miles to the east-northeast of Mauritius. Check the NASA Hurricane Page for satellite images and additional information on Tropical Storm 11S.
"Discovering the Deep" with NOAA's Okeanos Explorer in remote Pacific marine protected areas -- During the most of the month of March (running from the 7th through the 29th), NOAA and partners will conduct a telepresence-enabled ocean exploration expedition onboard the NOAA Ship Okeanos Explorer to collect critical baseline information about unknown and poorly known deepwater areas in the Howland and Baker Unit of the Pacific Remote Islands Marine National Monument and the Phoenix Islands Protected Area. [NOAA Okeanos Explorer Media]
Updated El Niño/Southern Oscillation (ENSO) Diagnostic Discussion is released -- Late last week forecasters at NOAA's Climate Prediction Center (CPC) and the International Research Institute for Climate and Society (IRI) released their monthly El Niño/Southern Oscillation (ENSO) Diagnostic Discussion. They reported an ENSO-neutral situation during February 2017 with neither El Niño nor La Niña conditions as near normal sea surface temperatures (SST) were found across the central equatorial Pacific Ocean, but above average SST values were located in the eastern equatorial Pacific. Most of the prediction models used by the forecasters indicate a continuation of ENSO-neutral conditions through late spring and early summer in the Northern Hemisphere (May-July), with a increasing chances for development of an El Niño during autumn. [NOAA Climate Prediction Center]
An ENSO blog was written by a contractor with NOAA's CPC describing the current ENSO-neutral conditions across the equatorial Pacific. A discussion is made of the modeling efforts used by the CPC forecasters and their colleagues to make forecasts of the sea surface temperatures over sections of the equatorial Pacific Ocean through the first three months of 2018. [NOAA Climate.gov News]
An El Niño forecast from Down Under -- Forecasters with the Australian Bureau of Meteorology recent reported that several ENSO (El Niño-Southern Oscillation) indicators suggest that the current ENSO-neutral conditions could develop into an El Niño event in the equatorial Pacific Ocean during this calendar year of 2017. The Bureau's ENSO Outlook status has been upgraded to an El Niño WATCH, meaning the likelihood of El Niño forming in 2017 is approximately 50%. [Australian Government Bureau of Meteorology]
First "flashy" images arrive from lightning mapper on GOES-16 -- During the last week the first images of lightning activity obtained from the Geostationary Lightning Mapper (GLM) onboard the new GOES-16 satellite were released. The GLM images were superimposed upon full disk images from the satellite's Advanced Baseline Imager. Colors on these GLM images indicate more lightning activity as measured in kilowatt-hours of total optical emissions from the lightning. From the satellite's geosynchronous orbit, the Geostationary Lightning Mapper should continuously monitor lightning activity across most of the Western Hemisphere, providing forecasters with information as to when lightning storms begin or dissipate. [NOAA NESDIS News] or [NASA Goddard Space Flight Center Feature]
Phytoplankton colors Antarctic sea ice green -- A natural-color image obtained from data collected by the Operational Land Imager (OLI) on NASA's Landsat 8 satellite during the first week of March shows a green coloration of sea ice in Antarctic's Granite Harbor, a cove off the Ross Sea. The green color of the ice may be due to microscopic marine plants called phytoplankton in the surface waters. [NASA Earth Observatory]
Public input is solicited on proposed marine sanctuary in Lake Michigan -- During this week four public meetings will be held in several lakeshore communities in eastern Wisconsin by NOAA's Office of National Marine Sanctuaries. These meetings are being held to seek public comment on drafts of a management plan and an environmental impact statement on a proposed national marine sanctuary that would be situated in the waters of Lake Michigan offshore of Wisconsin's eastern lakeshore. This proposed national marine sanctuary would protect over 100 historically significant shipwrecks and related maritime heritage resources dating back into the 19th century. [NOAA Media Advisory]
Digital elevation models of ocean floor and coastal areas could help prepare for next tsunami -- NOAA scientists and their colleagues are developing computerized digital elevation models (DEM) that include both ocean depth data and coastal land elevation data to create visualizations of the relief in these coastal areas. The goal is to have high resolution DEM that can be used to understand the behavior of tsunami waves that could travel across the oceans and hit land masses with catastrophic results. The speed and height of tsunami waves, along with the distance they travel, are affected by the underwater topographic relief. More than 200 DEM models have been developed coastal communities in the US and elsewhere as part of the US Tsunami Forecast and Warning System. [NOAA News]
Improvement in the simulations of the Madden-Julian Oscillation is made --Researchers from the University of Hawaii, Colorado State University and China's Nanjing University of Information Science and Technology have evaluated current computer models that simulate the development and eastward movement of the Madden-Julian Oscillation across tropical latitudes. The Madden-Julian Oscillation is a large-scale disturbance in the atmospheric wind, cloud and precipitation patterns that typically recur every 30 to 60 days. The researchers' model inter-comparison revealed that a model's ability to successfully simulate this movement depends upon whether the model captures atmospheric response in areas of light rain following intense storms. [NOAA Climate Program Office News]
Use of taurine approved in fish feeds -- Scientists in the Aquaculture Program at the Northwest Fisheries Science Center (NWFSC) recently won approval from the American Association of Feed Control Officials (AAFCO) for the use of taurine in fish feeds after NWFSC scientists showed taurine, an amino acid supplement, is safe and beneficial to farmed marine fish. [NOAA National Fisheries' Northwest Fisheries Science Center News]
Picking a right spot for offshore wind energy -- A 16-minute NOAA Ocean Podcast was produced that contains an interview with two scientists from NOAA's National Centers for Coastal Ocean Science who describe how they and other NOAA scientists have conducted a variety of surveys using marine biogeography to help locate the best locations to place potential future alternative energy sites in the ocean. Marine biogeography entail the study of marine species, the geographic distribution of their habitats, and the relationships between living organisms and the environment. As an example of the four-step biogeographic assessment process, the scientists who were interviewed discussed their work on a project to develop an offshore wind energy project in Hawaii. [NOAA National Ocean Service Podcast]
Restoration project for oceanic fish is now underway -- Seven Louisiana fishers have volunteered to refrain from using their longline fishing gear through the end of this June in conjunction with the Pelagic Longline Bycatch Reduction Project developed by the Open Ocean Restoration Area project and its partner, the National Fish and Wildlife Foundation. [NOAA Gulf Spill Restoration]
An All-Hazards Monitor -- This Web portal provides the user information from NOAA's National Weather Service, FAA and FEMA on current environmental events that may pose as hazards such as tropical weather, fire weather, marine weather, severe weather, drought and floods. [NOAA/NWS Daily Briefing]
Earthweek -- Diary of the Planet [earthweek.com]

This Concept of the Week is repeated from Week 6.

Concept of the Week: Abyssal Storms

Until recently, ocean scientists thought of the deep ocean abyss as a dark and cold, but serene place where small particles rained gently onto the ocean floor. However, instruments lowered to the sea floor to measure ocean motion or currents and resulting mobilization of bottom sediments detected a much more active environment. Scientists found that bottom currents and abyssal storms occasionally scour the ocean bottom, generating moving clouds of suspended sediment. A surface current of 5 knots (250 cm/sec) is considered relatively strong. A bottom current of 1 knot (50 cm/sec) is ripping. Although this may be called an abyssal storm, the water motion pales by comparison to wind speeds in atmospheric storms.

Abyssal currents and storms apparently derive their energy from surface ocean currents. Wind-driven surface ocean currents flow about the margins of the ocean basins as gyres centered near 30 degrees latitude. (Refer to Figure 6.6 in your textbook.) Viewed from above, these subtropical gyres rotate clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. For reasons given in Chapter 6 of your textbook and this week's Supplemental Information, surface currents flow faster, are narrower, and extend to greater depths on the western arm of the gyres. These are known as western boundary currents and include, for example, the Gulf Stream of the North Atlantic basin. Abyssal currents are also most vigorous on the western side of the ocean basins, moving along the base of the continental rise, which is on the order of several kilometers deep.

Abyssal storms may be linked to or may actually be eddies (rings) that occasionally break off from the main current of the Gulf Stream (and other western boundary currents). During an abyssal storm, the eddy or ring may actually reach to the bottom of the ocean where the velocity of a bottom current increases ten-fold to about 1.5 km (1 mi) per hr. While that is an unimpressive wind speed, water is much denser than air so that its erosive and sediment-transport capacity is significant even at 1.5 km per hr. At this higher speed, the suspended sediment load in the bottom current increases by a factor of ten. Abyssal storms scour the sea floor leaving behind long furrows in the sediment. After a few days to a few weeks, the current weakens or the eddy (ring) is reabsorbed into the main surface circulation and the suspended load settles to the ocean floor. In this way, abyssal storms can transport tons of sediment long distances, disrupting the orderly sequence of layers of deep-sea sediments. Scientists must take this disruption into account when interpreting the environmental significance of deep-sea sediment cores.

Concept of the Week: Questions

(Place your responses on the Chapter Progress Response Form provided in the Study Guide.)

In the subtropical ocean gyres, boundary currents flow faster on the [(western)(eastern)] side of an ocean basin.
Currents in an abyssal storm erode, transport, and redeposit sediments that have accumulated on the [(continental shelf)(deep ocean bottom)].

Historical Events

13-15 March 1952...The world's 5-day rainfall record was set when a tropical cyclone produced 151.73 inches rain at Cilos, Reunion Island in the Indian Ocean. The 73.62 inches that fell in a 24-hour period (15^th-16^th) set the world's 24-hour rainfall record. (Accord's Weather Calendar)
14 March 1891...The submarine Monarch laid telephone cable along the bottom of the English Channel to prepare for the first telephone links across the Channel.
14 March 1903...President Theodore Roosevelt issued an executive order making Pelican Island near Sebastian Florida a "preserve and breeding ground for native birds," including pelicans and herons, marking the birth of the National Wildlife Refuge System. (Wikipedia)
14 March 1918...The first US concrete seagoing ship was launched at Redwood City, CA. (Today in Science History)
15 March 1493...Christopher Columbus returned to Spain after his first voyage to the New World. (Wikipedia)
15 March 1778...Nootka Sound, Vancouver Island was discovered by Captain James Cook.
15 March 1946...For the first time, U.S. Coast Guard aircraft supplemented the work of the Coast Guard patrol vessels of the International Ice Patrol, scouting for ice and determining the limits of the ice fields from the air. (USCG Historian's Office)
15 March 1960...Key Largo Coral Reef Preserve in the Florida Keys was established as the nation's first underwater park. This preserve currently includes John Pennekamp Coral Reef State Park and the adjacent Florida Keys National Marine Sanctuary.
16 March 1521...Portuguese navigator Ferdinand Magellan reached the Philippines. He was killed the next month by natives.
16 March 1834...The HMS Beagle anchored at Berkeley Sound, Falkland Islands.
16 March 1889...A war between the U.S. and Germany was likely averted as a hurricane sank all three U.S. and three German warships in the harbor at Apia, Samoa. Joint U.S., German and Samoan rescue cooperation led to the Treaty of Berlin (1889) that later settled the dispute. (Accord's Weather Calendar)
17 March 1891...The British steamer SS Utopia sank off the coast of Gibraltar, killing 574 people. (Wikipedia)
17 March 1898...The USS Holland, the first practical submarine, was demonstrated by John Holland as it made its first dive in the waters off Staten Island, New York for one hour and 40 minutes. (Naval Historical Center)
17 March 1941...USCGC Cayuga left Boston with the South Greenland Survey Expedition onboard to locate airfields, seaplane bases, radio and meteorological stations, and aids to navigation in Greenland. (USCG Historian's Office)
17 March 1959...The submarine USS Skate (SSN-578) surfaced at the North Pole. (Naval Historical Center)