Weekly Ocean News

DATASTREME OCEAN WEEK TWELVE: 2-6 December 2013

Items of Interest:

The 2013 hurricane seasons reviewed -- With the end of the official 2013 hurricane season in both the North Atlantic and North Pacific on Saturday (30 November 2013), a quick review of this year's tropical cyclone statistics for the official 2013 hurricane season has been made for both basins. [AMS DataStreme Atmosphere] Additional information is available from NOAA News.
For those who are interested in obtaining historic hurricane information, the "Historical Hurricanes Mapping & Analysis Tool" developed by NOAA allows the search and display of detailed data for more than 6000 tropical cyclones in seven of the planet's major ocean basins based upon a data set that runs from 1842 to 2012. Coastal population trends are also available for the Atlantic and Gulf Coasts of the United States.
Tropical cyclone climatologies of North Atlantic and the eastern North Pacific -- The National Hurricane Center (NHC) has an updated and revised edition of its "Tropical Cyclones of the North Atlantic Ocean, 1851-2006." While a paper copy of this book is available for a cost from NHC, a 243-pg pdf file of this edition can be downloaded for free. NHC also released the first edition of "Tropical Cyclones of the Eastern North Pacific Ocean, 1949-2006." In addition to a paper copy is available for sale, a free 164-page pdf file is available. Both of these climatologies have numerous graphics that show long-term changes in tropical cyclone frequency in the two basins.
A climatology of tropical cyclones in the central North Pacific from the 1950s to 2008 is available from the CPHC climatology website maintained by the Central Pacific Hurricane Center (CPHC) in Honolulu, HI.
Program connects students with NOAA coral reef scientists -- NOAA Reef Smart, a Coral Reef Ecosystem Education Initiative, is collaborating with JASON Learning, a non-profit educational organization, in producing interactive webcasts that enable students to communicate with NOAA coral scientists. This NOAA Reef Smart program is designed to link the science fundamentals youngsters are learning in school to real-life applications of coral reef science and future careers in science, technology, engineering, and math. The webcasts consisted of video, dialogue, and interactive features. An upcoming webcast is scheduled for this Thursday 5 December. The NOAA Reef Smart Initiative is a series of strategic, community-based outreach events designed to increase awareness of NOAA's coral reef ecosystem research done in partnership with National Centers for Coastal Ocean Science (NCCOS) and NOAA's Coral Reef Conservation Program. [NOAA NCCOS News]
It's Sure Dark! -- Have you noticed that the sun is setting early these days? During the first ten days of December, many locations throughout the country will experience their earliest sunset times of the year. The exact day for the earliest sunset depends upon the latitude, so you may want to check the date in your locale from the sunrise tables appearing in an on-line, interactive service available for the entire year at most cities in the United States. The reason for the earliest sunsets occurring in early December rather than on the winter solstice (during the morning hours of Saturday, 21 December 2013) is that the sun is not as precise a timekeeper as our watches. Because of a combination of factors involved with Earth's elliptical orbit about the sun and the tilt of Earth's spin axis with respect to the plane of the ecliptic, the sun appears to "run fast" by as much as 15 minutes as compared with clock time in November. However, with the approach of the winter solstice and perihelion (the smallest earth-sun distance during the early morning of 4 January 2014), the apparent sun slows during December and finally lags the clock by 12 minutes in February. Consequently, a noticeable and welcome trend toward later sunsets can be detected by the end of December, especially by those residents in the northern part of the country. However, the latest sunrises occur at most locales in early January, meaning that early risers will continue seeing dark and dreary mornings for another month.
Accessing and interpreting climate data -- If you would like to obtain a variety of climate data for your home town or state that are available from the National Weather Service, please read this week's Supplemental Information...In Greater Depth. This Supplemental not only identifies some of the sites to find the data, but also provides you with a brief explanation of the terminology used to identify the climate data.

Ocean in the News:

Eye on the tropics --- No tropical cyclone activity was reported across either the North Atlantic and eastern North Pacific basins during the last week as the official hurricane seasons in both basins drew to a close. Elsewhere, tropical cyclone activity was relatively light last week across the other world's tropical ocean basins:

In the North Indian Ocean basin, Tropical Storm Lehar traveled toward the west-northwest across the Bay of Bengal, becoming a category 1 cyclone on the the Saffir-Simpson Scale at the start of last week. By late in the week, Cyclone Lehar weakened to a tropical depression before making landfall along the coast of eastern India south of Machillipatnam. The NASA Hurricane Page has more information and satellite images for Cyclone Lehar.
In the South Indian Ocean basin, Tropical Storm Alessia made landfall along the coast of Australia's Northern Territory to the south of Darwin over the previous weekend. Alessia weakened to become a remnant low as it traveled eastward across the Northern Territory. However, as Alessia moved out into the Gulf of Carpentaria, it re-intensified into a tropical storm for a few hours at the midpoint of last week. Alessia weakened to a tropical depression to the west of Mornington Island, Queensland, Australia. Redevelopment over the Gulf of Carpentaria meant that Tropical Storm Alessia was the first named tropical cyclone of the 2013-2014 cyclone season in the western South Pacific basin. Satellite imagery and additional information are available on the NASA Hurricane Page for Tropical Storm Alessia.

National Weather Service Director discusses Super typhoon Haiyan and climate change -- Dr. Louis Uccellini, the Director of the National Weather Service, was recently interviewed by CNN and was asked about the a link between the intensity of last month's Super Typhoon Haiyan over the Philippines and climate change. He said that while the number of tropical cyclones may not be increasing, some of the storms may have become more intense. He also noted that coastal populations are increasingly vulnerable as climate change drives an increase in sea levels. [NOAA WeatherReady Nation News]
Australian tropical cyclone season outlook issued -- Forecasters at the Australian Government's Bureau of Meteorology recently released an outlook for the upcoming 2013-14 Australian tropical cyclone season that typically begins in November and runs through April. These forecasters foresee close to average tropical cyclone activity in the five regions that surround that continent. Their outlook is based upon the El Niño - Southern Oscillation (ENSO) status during the preceding July to September period. Close to average tropical cyclone activity is anticipated as ENSO-neutral conditions, which tend to favor average activity, were present during this most recent period and are expected to continue through this upcoming austral summer. [Australian Bureau of Meteorology]
Solution offered to impacts made on coral reefs by pollution -- In a controlled study conducted over three years in the Florida Keys, marine scientists from Oregon State University, Florida International University and the University of Florida have found that increased nitrogen and phosphorus levels from sewage, agricultural practices and other sources can lead to coral disease and bleaching. This three-year study in which nutrient levels were elevated, showed that disease to the coral doubled and the amount of coral bleaching more than tripled. The researchers suggest that coral health could be improved by reducing nutrient overloads through improved sewage treatment or best-management practices to minimize fertilizer runoff from agricultural or urban use. [Oregon State University News]
Releases of Arctic seafloor methane double previous estimates -- Scientists from the University of Alaska Fairbanks and their colleagues from Russia, Sweden and the US have discovered the seafloor in the Arctic Shelf off the coast of northern Siberia venting more than twice the amount of methane as previously estimated. They claim that this amount of methane is comparable to the amount released from the arctic tundra. Methane, a greenhouse gas, is stored on the seafloor as a pre-formed gas or as methane hydrates. [University of Alaska Fairbanks Cornerstone News]
Methane emissions nationally and in California 50 percent greater than expected -- Using a method they devised for more accurate methane estimations, researchers at the US Department of Energy's Lawrence Berkley National Laboratory have discovered that the current official inventories of methane gas emissions nationally and from California may be underestimated by a factor of 1.5. Methane emissions from oil and gas production may account for a significant portion of the underestimated emissions both in California and nationwide, and may be as much as five times greater than the current inventory estimates of EDGAR (Emissions Database for Global Atmospheric Research), the most comprehensive global methane database. [Lawrence Livermore National Laboratory News Center]
Subglacial lakes discovered under Greenland Ice Sheet -- Using airborne radar measurements, researchers at the United Kingdom's Scott Polar Research Institute at the University of Cambridge have discovered two subglacial lakes under the Greenland Ice Sheet. These subglacial lakes apparently will influence the ice sheet flow, which would impact global sea-level change. Their discovery is important for understanding how ice will respond to changing environmental conditions. [University of Cambridge Research News]
Volcanic eruptions could have triggered ancient mass extinction -- Researchers with the Carnegie Institution for Science and of the Massachusetts Institute of Technology claim that the largest mass extinction in history at the end of the Permian period approximately 250 million years ago may have been triggered by large volcanic eruptions in present-day Siberia. More than 90 percent of the marine species were lost, along with 70 percent of the terrestrial species, with full recovery taking several million years. The volcanic eruptions apparently released large quantities of carbon dioxide and sulfur dioxide gases that created highly acidic rain that leached the soil of nutrients. In addition, halogen-bearing compounds could have resulted in a reduction in the protective global ozone shield. [Carnegie Institution for Science News]
An All-Hazards Monitor -- This Web portal provides the user information from NOAA on current environmental events that may pose as hazards such as tropical weather, drought, floods, marine weather, tsunamis, rip currents, Harmful Algal Blooms (HABs) and coral bleaching. [NOAAWatch]
Earthweek --

earthweek.com

Requires Adobe Acrobat Reader.

Concept of the Week: Climate Feedback Processes

Earth's climate system includes many interacting variables. Some variables are external to the Earth-atmosphere system and some are internal. External variables include solar energy output and Earth-sun geometry (i.e., the Milankovitch cycles). Internal variables include properties of the Earth's surface (e.g., albedo, moisture), the concentration of key atmospheric components (e.g., greenhouse gases, sulfurous aerosols), and cloud cover and thickness.

An important consideration in understanding how Earth's climate system responds to some perturbation is feedback. Feedback is defined as a sequence of interactions among variables in a system that determines how the system responds to some initial perturbation in one or more of the variables. Variables in Earth's climate system may interact in such a way as to either amplify (positive feedback) or lessen (negative feedback) a change in climate. An example of positive feedback is the ice-albedo effect described in Chapter 12 of the DataStreme Ocean textbook. Less ice cover in the Arctic greatly reduces the albedo of the Arctic Ocean causing higher sea surface temperatures and accelerated melting of the multiyear pack ice.

Consider an example of negative feedback. Increasing concentrations of atmospheric carbon dioxide enhances the greenhouse effect causing global warming. Global warming in turn raises sea surface temperatures and increases the rate of evaporation. A more humid atmosphere means more persistent and thicker cloud cover but clouds have both a cooling and warming effect on the lower atmosphere. The relatively high albedo of cloud tops causes cooling whereas absorption and emission of infrared radiation by clouds causes warming by contributing to the greenhouse effect. Satellite measurements and numerical models indicate that cooling would dominate.

In general, negative feedback tends to dominate over positive feedback in Earth's climate system, limiting the magnitude of climate change. The great thermal inertia of the ocean is the principal reason for dampening the planetary temperature response.

Concept of the Week: Questions

Feedback in Earth's climate system that amplifies climate change is described as [(positive)(negative)] feedback.
In general, [(negative)(positive)] feedback tends to prevail in Earth's climate system.

Historical Events:

2 December 1755...The second Eddystone Lighthouse near Plymouth, England was destroyed by fire. This light had replaced an earlier light that had been destroyed in the "Great 1703 Storm." The current structure is the fourth light to be constructed at that site. (Wikipedia)
3 December 1952...A remarkable display of sea smoke was seen in Hong Kong harbor. The sea-smoke, induced by a strong surge of arctic air, poured from the water of Kowloon Bay from 8 AM to 9:30 AM. The air temperature near the sea wall was 44 degrees F. (Accord Weather Guide Calendar)
3 December 1992...The Greek oil tanker Aegean Sea carrying 80,000 tons of crude oil ran aground in a storm while approaching La Coruña, Spain, spilling much of its cargo. (Wikipedia)
3 December 1999...After rowing for 81 days and 2962 miles, Tori Murden became the first woman to cross the Atlantic Ocean by rowboat alone when she reached Guadeloupe after departing from the Canary Islands. (Wikipedia)
4 December 1786...The first of two great early December storms began. The storm produced high seas at Nantucket that did great damage. (David Ludlum)
4-13 December 1991...Tropical Cyclone Val with gusts to 150 mph caused $700 million damage. Seventeen deaths were reported in American and Western Samoa, with 95 percent of the houses in Savaii either destroyed or badly damaged. Savaii was essentially hit twice by Val as the system completed a loop on the 8^th. (Accord Weather Guide Calendar)
4 December 2003...A tropical depression became Tropical Storm Odette in the Caribbean well south of Kingston, Jamaica, becoming the first December tropical storm of record to form in the Caribbean Sea. Odette made landfall on near Cabo Falso, Dominican Republic on 6 December, causing eight deaths and destroying 35 percent of the banana crop. (Accord Weather Guide Calendar)
5 December 1872...A British brigantine, the DeGratia, discovered the American ship Mary Celeste derelict and boarded her. The Mary Celeste, a brigantine had set sail from New York harbor for Genoa, Italy, on 5 November 1872. Everyone aboard the Mary Celeste had vanished-her captain, his family, and its 14-man crew. The ship, which appeared to have been abandoned for approximately nine days, was in perfect order with ample supplies and there was no sign of violence or trouble. The fate of the crew remains unknown. (Infoplease.com) (Wikipedia)
5 December 1492...The explorer Christopher Columbus became the first European to set foot on the island of Hispaniola, which now contains the countries of Haiti and the Dominican Republic. (Wikipedia)
5 December 1949...A typhoon struck fishing fleet off Korea; several thousand men reported dead. (Infoplease.com)
6 December 1830...The US Naval Observatory, the first U.S. national observatory, established as the Depot of Charts and Instruments in Washington, DC, under commander of Lieutenant Louis Malesherbes Goldsborough. Its primary mission was to care for the U.S. Navy's chronometers, charts and other navigational equipment. (Naval Historical Center)
7-8 December 1703...A monstrous storm raked southern England and adjacent waters with winds in excess of 100 mph. Approximately 8000 deaths were the result of this storm, mostly at sea. Many naval and supply ships were anchored in harbors or in the English Channel. The Eddystone Lighthouse disappeared. (Accord Weather Guide Calendar)
7 December 1872...An expedition put to sea from Sheerness aboard the corvette H.M.S. Challenger under the command of Captain George Nares on a 3 1/2-year world oceanographic cruise. During the 68,890 nautical mile cruise that ended on 24 May 1876, the ship traversed the North and South Atlantic and Pacific Oceans, traveled north of the limits of drift ice in the North Atlantic polar seas and south of the Antarctic Circle. The scientists onboard the Challenger sounded the ocean bottom to a depth of 26,850-ft, found many new species, and provided collections for scores of biologists. (Today in Science History)
7 December 1932...The first gyro-stabilized vessel to cross the Atlantic, the Conte di Savoia of the Italian Line, arrived in New York City. The ship had 48,502 gross tons, an overall length 814.6 ft by beam 96.1 ft, two funnels, two masts, four screws and a speed of 27 knots. As one of the first ships to be fitted with gyrostabilizers, it was claimed that rolling was limited to a maximum of three degrees. The maiden voyage began from Genoa to Villefranche and New York on 30 November 1932. (Today in Science History)
8 December 1777...Captain James Cook left the Society Islands (French Polynesia).
8 December 1866...The first transpacific side-wheeler steamship launched in the U.S. was the Celestial Empire (later named China) with capacity for 1,300 passengers. The builder, William H. Webb of New York, introduced many features of naval architecture in this liner, since in common use. (Today in Science History)
8 December 1993...The U.S. Secretary of Defense declared that the Global Positioning System (GPS), accurate within 100 meters, had 24 GPS satellites operating in their assigned orbits, available for navigation use at Standard Positioning Service (SPS) levels for civil users. This worldwide satellite-based radionavigation system used as the Defense Department's primary radionavigation system provided authorized users encrypted Precise Positioning Service accurate to at least 22 meters. (Today in Science History)
8 December 2002...Super-typhoon Pongsona hit Guam with sustained winds of 144 mph and gusts to 173 mph, along with a storm surge to 20 feet. The 40-mile wide diameter eye was over Anderson AFB for 2 hours. One indirect death and 193 injuries were attributed to the typhoon. Some bridge pavement was "scrapped off" by wind and wave action. Damage was estimated at $700 million. (Accord Weather Guide Calendar)