Weekly Ocean News

2-6 October 2017

Items of Interest

First sunrise of spring season at South Pole -- While residents in the Northern Hemisphere are experiencing shorter daylight following the recent passage of the autumnal equinox, a photograph made by a NOAA Corps officer stationed at the agency's South Pole Atmospheric Baseline Observatory captures the first sunrise of this new spring season (for the Southern Hemisphere) at the South Pole. [NOAA News]
World Space Week is celebrated -- The United Nations General Assembly has declared the week of 4 to 10 October to be "World Space Week" that is designed to "celebrate each year at the international level the contributions of space science and technology to the betterment of the human condition” Last year, more than 2,700 events were held in 86 countries to celebrate the benefits of space and excitement about space exploration. The theme for World Space Week 2017 is “Exploring New Worlds In Space.” we aim to inspire even more events around the world in October 2017. [United Nations]
High tides expected along the Middle Atlantic and Southeast coasts -- NOAA's National Ocean Service has recently released its High Tide Bulletin for the Fall of 2017. Ocean tides are expected to be higher than normal between 7 and 9 October along the US Atlantic Coast extending from New Jersey southward to the eastern coast of Florida because expanded warm ocean water, changes in weather patterns and the occurrence of a high astronomical tides due to Thursday's full moon followed by lunar perigee on Monday, 9 October. Higher than normal tides are also anticipated for early November. [NOAA National Ocean Service News]
Celebrate National Seafood Month -- The US Department of Commerce, along with one of its agencies, NOAA Fisheries, is celebrating this month of October 2017 as National Seafood Month. According to statistics compiled by this agency the seafood industry supports 1.2 million jobs nationwide and added $55 billion to the nation's GDP in 2011. [NOAA Fisheries]
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 --- Following an exceptionally strong tropical cyclone activity across the Atlantic and Pacific basins of the Northern Hemisphere during the first three weeks of September, fewer tropical cyclones were found across these basins during the last week:

In the North Atlantic Basin (that also includes the Caribbean Sea and Gulf of Mexico), Hurricane Lee was essentially stationary over the waters of the central North Atlantic at the start of last week. At that time, Lee was a category 1 hurricane on the Saffir-Simpson Scale, with its center located approximately 910 miles to the east of Bermuda or 1355 miles to the west of the Azores. Early in the week, Lee strengthened as it traveled westward. Turning toward the north, Lee became a major category 3 hurricane at midweek (last Wednesday) as maximum sustained surface winds reached 115 mph when Lee was located approximately 460 miles to the east of Bermuda. While traveling toward the northeast during the second half of last week, Lee weakened to a tropical storm. As of Friday morning (local time), Tropical Storm Lee became a post tropical cyclone or remnant low approximately 745 miles to the north-northwest of the Azores. The NASA Hurricane Page has satellite images and additional information on Hurricane Lee.
The seventh Atlantic hurricane of 2017, Hurricane Maria, continued to travel toward the north offshore of the coast of the Carolinas at the start of last week after wreaking havoc on Puerto Rico, the Virgin Islands and several other Caribbean Islands at the end of the previous week. During the early part of last week, Hurricane Maria had weakened to tropical storm status, before intensifying again to become a hurricane. On Thursday, Maria weakened to a tropical storm for a second time as it began a trek toward the east away from the East Coast. At that time, the center of Tropical Storm Maria was approximately 275 miles to the east-northeast of Cape Hatteras, NC. Traveling toward the east, Maria continued to weaken and loose its tropical characteristics, becoming an extratropical cyclone (or midlatitude storm) by last Saturday afternoon as it was located approximately 560 miles to the east-southeast of Cape Race, Newfoundland. The NASA Hurricane Page has additional information and satellite images of Hurricane Maria.
In the eastern North Pacific basin (to the east of the 140 degrees west meridian of longitude), Tropical Storm Pilar was traveling northward approximately 30 miles to the north-northwest of Las Islas Marias, Mexico, an archipelago of four islands off the western coast of Mexico, at the start of last week. By midmorning on Monday, this tropical storm had weakened to a tropical depression as it continued to travel toward the north-northwest. As of midafternoon last Monday, Tropical Depression Pilar dissipated approximately 60 miles to the northwest of Mazatlan, Mexico. Additional information and satellite images associated with Tropical Storm Pilar are available on the NASA Hurricane Page.
In the western North Pacific basin (to the west of the International Dateline), Tropical Depression 22-W (TD-22W) had formed over the South China Sea near the Philippine Islands over the previous weekend, At the start of last week, TD-22W passed across China's Hainan Island and made a landfall along the coast of northeastern Vietnam last early Tuesday (local time). See the NASA Hurricane Page for more information on TD-22W.

Aerial photos available to assess Maria's destruction across Caribbean -- A large number of high-definition aerial photographs are being made available of areas of Puerto Rico and the US Virgin Islands that were damaged by last month's Hurricane Maria. These aerial photographs have been made by remote-sensing cameras mounted aboard NOAA aircraft that were flown at altitudes between 1500 and 5000 feet by teams from NOAA's Office of Marine and Aviation Operations and NOAA's National Geodetic Survey. [NOAA News]
Satellites provide view of damage inflicted upon Puerto Rico by Maria -- A team of scientists from NASA's Goddard and Marshall Space Flight Centers recently created interactive images that show those areas of Puerto Rico that remain without electric power following the passage of Hurricane Maria last month. This team overlaid nighttime light data collected from the VIIRS instrument on the NOAA/NASA Suomi NPP satellite upon a base map generated from data obtained by the Landsat, Sentinel-2, TanDEM-X, and TerraSAR-X satellites. [NASA Earth Observatory]

NASA Earth Observatory

Monitoring this year's climate across Hawaii and the Pacific Islands -- A "Beyond the Data" blog was recently written for the ClimateWatch Magazine that shows how the weather and climate conditions for Hawaii and the U.S. Affiliated Pacific Islands so far in 2017 compare with long-term averages. Attention is directed to higher than average local sea levels around Hawaii, above-average rainfall totals across many of the US Pacific Islands and above-average sea surface temperatures across large areas of the tropical Pacific. [NOAA Climate.gov News]
International project commences to map the entire ocean floor -- The General Bathymetric Chart of Oceans (GEBCO), an international group of ocean mapping experts, is partnering with the Nippon Foundation of Tokyo, Japan, a private, non-profit grant-making organization, to compile all available and newly collected bathymetric data into a high-quality, 100-m-resolution digital model of the ocean floor. The initiative is called Seabed 2030 to identify the goal of completing mapping of the ocean floor by 2030. This consortium is promoting international efforts to collect new data.[NOAA NCEI News]
Lake Michigan's underwater resources are mapped -- During this past summer, maps of the underwater resources found in the waters of western Lake Michigan off the coast of Wisconsin were prepared in support of the proposed Wisconsin-Michigan Marine Sanctuary. NOAA's Office of National Marine Sanctuaries and the Great Lakes Environmental Research Laboratory collected 322 underwater videos as part of the National Coastal Mapping Program. Sonar data were also obtained. The videos and sonar data provided new perspectives of the geology, ecology and maritime heritage of this seldom-explored swath of Lake Michigan. [NOAA National Centers for Coastal Ocean Science News]
Workshop held for National Harmful Algal Bloom Observing Network -- Representatives from five NOAA Line Offices recently met for two days at NOAA Headquarters to form the National Harmful Algal Bloom Observing Network (NHABON) Working Group. This focus of this workshop was to document current harmful algal bloom (HAB) observing capabilities and identify gaps in existing regional observing networks around the nation that include six priority regions (Pacific Northwest, Florida, Lake Erie, California, Gulf of Maine, Texas). [NOAA National Centers for Coastal Ocean Science News]
Satellite sees persisting algal bloom in Lake Erie -- A natural-color image was recently made of Lake Erie from data collected by the MODIS sensor onboard NASA's Terra satellite. The image shows a green color in the waters of western Lake Erie that marks the continuation of the phytoplankton bloom, the result of warm lake waters and large amounts of nutrients from agricultural runoff.[NASA Earth Observatory]
The National Marine Sanctuary System turns 45 years old -- NOAA's National Marine Sanctuary System will observe its 45th anniversary this month, as the Marine Protection, Research, and Sanctuaries Act was passed by the US Congress and signed into law by President Richard Nixon in October 1972. This Act was intended to regulate intentional ocean disposal of materials and to authorize any related research. Title III of that Act created what was then known as the National Marine Sanctuaries Program. [NOAA National Marine Sanctuaries News]
New look at new Antarctic iceberg from space -- With the increase in daylight across the Antarctic continent, sensors onboard NASA's Landsat 8 satellite have provided recent visible satellite images of the new massive iceberg that broke off Antarctica's Larsen C ice shelf this past July. [NASA Earth Observatory]
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]

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.

Historical Events

2 October 1836...The British naturalist Charles Darwin returned to Falmouth, England, aboard the HMS Beagle, ending a five-year surveying expedition of the southern Atlantic and Pacific Oceans, that included visits to Brazil, the Galapagos Islands, and New Zealand. The information and experience obtained from this voyage led Darwin to develop his historic work on the theory of evolution and the 1859 publication entitled, The Origin of Species by Means of Natural Selection. (The History Channel)
2 October 1858...The only hurricane to impact California struck San Diego on this day. Two NOAA researchers, Michael Chenoweth and Christopher Landsea, reconstructed the path of the hurricane using accounts from newspapers of the strong winds. They estimated that if a similar storm were to have hit in 2004, it would have caused around US$500 million in damage. (National Weather Service files)
2 October 1867...A hurricane struck Galveston, TX with a storm tide that caused $1 million damage. (Intellicast)
2 October 1882...A major hurricane struck the Louisiana Delta with 100-mph winds and 12-ft storm tide which inundated the bayous resulting in 1500 deaths. (Intellicast)
2 October 1898...A hurricane struck the Weather Bureau (now National Weather Service) hurricane observation post at Carolina Beach, North Carolina and swept away the office's outhouse. The storm became known as the "Privy Hurricane" and was estimated to be a category 3 or 4 hurricane with winds around 130 mph. (Northern Indiana NWSFO)
3 October 1780...A hurricane, which formed on 1 October, destroyed the port city of Savanna-la-Mar on the island of Jamaica on this day. By some estimates, this hurricane caused 3,000 deaths. (National Weather Service files)
3 October 1841...The "October Gale," the worst of record for Nantucket, MA, caught the Cape Cod fishing fleet at sea. Forty ships were driven ashore on Cape Cod, and 57 men perished from the town of Truro alone. Heavy snow fell inland, with 18 inches reported near Middletown, CT and 3 inches at Concord, MA. (David Ludlum)
4 October 1582...The Gregorian Calendar was implemented by Pope Gregory XIII to correct for an increasing discrepancy between the leap year corrections of the Julian Calendar and the actual length of the year marked by the Earth's orbit of the sun. In Italy, Poland, Portugal, and Spain, 4 October of this year was followed directly by 15 October, skipping over 10 days. (Wikipedia)
4 October 1869...A great storm struck New England. The storm reportedly was predicted twelve months in advance by a British officer named Saxby. Heavy rains and flooding plagued all of New England, with strong winds and high tides along the coast of New Hampshire and Maine. Canton, CT was deluged with 12.35 inches of rain. (David Ludlum)
4 October 2005...Hurricane Stan, a minimal Category 1 hurricane with 75 mph maximum sustained surface winds, made landfall near Punta Roca Partida, Mexico at 4 AM EDT on this day. While not a particularly strong hurricane the torrential rains caused flooding and landslides, which resulted in 1513 deaths in Guatemala. (National Weather Service files)
5 October 1864...A tropical cyclone hit India near Calcutta, devastating the city and killing about 60,000 people in the region. (National Weather Service files)
6 October 1963...For five days along the coast of Cuba, Hurricane Flora lashed the island with winds up to 100 mph and dumped over 70 inches of rain. The storm killed 7,000 people. (National Weather Services files)
7 October 1737...A furious cyclone in the Bay of Bengal caused a major disaster at the mouth of the Hoogby River near Calcutta, India. As many as 300,000 people were killed, mainly as the result of the storm's forty foot high surge. (Accord Weather Guide Calendar)
7 October 1844...A major hurricane swept over Jamaica, Cuba, and the Bahamas. 158 vessels were wrecked and 2546 houses were destroyed along the Cuban coast. (National Weather Services files)