el nino southern oscillation – NOAA Teacher at Sea Blog

September 16, 2008April 2, 2021

Mary Anne Pella-Donnelly, September 16, 2008

NOAA Teacher at Sea
Mary Anne Pella-Donnelly
Onboard NOAA Ship David Jordan Starr
September 8-22, 2008

Mission: Leatherback Use of Temperate Habitats (LUTH) Survey
Geographical Area: Pacific Ocean –San Francisco to San Diego
Date: September 16, 2008

Weather Data from the Bridge
Latitude: 3720.718 N Longitude: 12230.301
Wind Direction: 69 (compass reading) NW
Wind Speed: 12.0 knots
Surface Temperature: 15.056

Scott measures a moon jelly as Amy records data.

Science and Technology Log

The LUTH Survey is a collaborative effort to gather as much oceanographic data from this small part of the Pacific Ocean as possible. Although the primary objective is to characterize this area for its potential as leatherback habitat, it is also an opportunity for other scientists to gather data that reinforces their studies. Everyone on this cruise, aside from myself, is employed by the National Oceanographic and Atmospheric Administration’s National Marine Fisheries Service. The regional area that this group works in is the Southwest Fisheries Science Center. There are nine scientists who have very different specializations. The following flow chart outlines how each department is related to the others.

Crewmembers practice suction cup tagging of leatherbacks from a Rigid Hull Inflatable Boat (RHIB).

Every division is focused on different aspects of oceanography. Scott Benson is our chief scientist and leatherback specialist. Karin Forney is the research biologist on the team whose expertise is marine mammals and regulations out to the limit of United States waters. This limit is the EEZ – Exclusive Economic Zone – and extends for 200 miles west of the coast. Peter Dutton is currently the leader of the Marine Turtle Genetics Program, here to gain additional insight into foraging habitats of the leatherback. Liz Zele, oceanographer, and Justin Garver as oceanography intern, manage the collection and processing of oceanographic data from the CTDs and XBTs. Steven Bograd is supporting the data collection as a research oceanographer. Both George (Randy) Cutter and Juan Zwolinski collect and interpret the acoustic data. Randy’s area of expertise is with fisheries acoustics, seafloor mapping and autonomous underwater vehicles. Juan’s specialty is in acoustic estimation of small pelagic fish. Amy Hapeman is aboard as a permit analyst to gain a better understanding of how the science data are collected. Together, this dynamic group will work to put together a better picture of what habitat might be available to leatherback turtles here off the continental shelf of California. They are all excited to be here, greatly enjoy their professions, and hope to assist in leatherback turtle protection.

Justin prepares to collect head and organs for research.

The night of September 13, a few members of the research team, with assistance from crewmembers, took advantage of the relatively warm water the Jordan was crossing and tried to fish for squid. Not really expecting much more than a short fight with a 12 inch mollusk, we were in for a surprise. Using a fluorescent lure, and a 50lb test, the line was dropped about 200m into the dark sea. Within 5 minutes, the line began to tug, and tug, AND TUG!! The oceanographer/fisher used a tremendous amount of strength to reel in the organism on the other end of the line. Victor, crewmember and experienced squid fisher, gaffed the squid as soon as it surfaced in the water. Shock was on every face as we acknowledged we were not expecting a 65cm long, 30-40lb animal! As soon as the tentacles that it grabbed the lure with were detached from the lure, Justin was ready to go again! And within 5 minutes another squid was caught, easily the same size as the first. This brought another three scientists and one crewmember out with additional reels.

Two Humboldt squid fresh from the Pacific!

Within an hour, eight squid were aboard, plans were made for a calamari feast and measuring began. Karin Forney, after observing the commotion, quickly retrieved an email from a colleague who is conducting research on this species of squid, and who requested that we preserve the head and internal organs for later genetic analysis. Several Ziplock bags were readied and the cleaning began. In the end there were calamari steaks for everyone and their 10 best friends, tentacles for several pots of soup and research samples collected for additional analysis. This species of squid is of concern since it had been uncommon off the central California coast until after the 1998 El Nino event, which brought warm waters up from the tropical Pacific side. Now it is much more abundant. The Humboldt squid is a voracious predator and there is great interest in understanding its potential impact on other species, especially those of commercial value.

Randy and Mary Anne cleaning Humboldt Squid.

Animals Seen Today
Blue shark Prionace glauca, Humboldt squid Dosidicus gigas, Arctic tern Sterna paradisaea, and Common redpoll Carduelis flammea.

Words of the Day
Gaff: hook attached to a long pole used to bring in a catch Characterize: to decide what the parts are that together create something Acoustic: sound wave information El Nino: a cyclic climate event originating in the tropical Pacific that is associated with unusually warm waters that impact the west coast of North and South America.

Joao preparing his secret calamari marinade.

Questions of the Day

A squid is classified as a mollusk, which is a single shelled marine animal. Where is the single shell on this animal?
What are some of the reasons the study of leatherback turtles is so complex?

November 1, 2006April 1, 2021

Karolyn Braun, November 1, 2006

NOAA Teacher at Sea
Karolyn Braun
Onboard NOAA Ship Ka’imimoana
October 4 – 28, 2006

Mission: TAO Buoy Array Maintenance
Geographical Area: Hawaii
Date: November 1, 2006

Plan of the Day: Arrive in Kwajalein, RMI

TAS Braun assists in driving the KA’IMIMOANA

In many of my past journal entries I have talked about El Niño or ENSO, so what is it? Well El Niño is an oscillation of the ocean-atmosphere system in the tropical Pacific having important consequences for weather around the globe. Among these consequences is increased rainfall across the southern tier of the US and in Peru, which has caused destructive flooding, and drought in the West Pacific, sometimes associated with devastating brush fires in Australia. Observations of conditions in the tropical Pacific are considered essential for the prediction of short-term (a few months to 1 year) climate variations. To provide necessary data, NOAA operates and assists in the TAO buoy project, which measure temperature, currents and winds in the equatorial band. These buoys daily transmit data, which are available to researchers and forecasters around the world in real time.

In normal, non-El Niño conditions the trade winds blow towards the west across the tropical Pacific. These winds pile up warm surface water in the west Pacific, so that the sea surface is about 1/2 meter higher at Indonesia than at Ecuador. The sea surface temperature is about 8 degrees C higher in the west, with cool temperatures off South America, due to an upwelling of cold water from deeper levels. This cold water is nutrient-rich, supporting high levels of primary productivity, diverse marine ecosystems, and major fisheries. Rainfall is found in rising air over the warmest water in the west Pacific, and the east Pacific is relatively dry.

The track of the KA’IMIMOANA for TAS Braun’s science cruise. — The track of the KA’IMIMOANA for TAS Braun’s science cruise (in light blue).

During El Niño, the trade winds relax in the central and western Pacific leading to a depression of the thermocline in the eastern Pacific, and an elevation of the thermocline in the west. This reduces the efficiency of upwelling to cool the surface and cut off the supply of nutrient rich thermocline water to the euphotic zone. The result is a rise in sea surface temperature and a drastic decline in primary productivity, the latter of which adversely affects higher trophic levels of the food chain, including commercial fisheries in this region. The weakening of easterly trade winds during El Niño is also evident. Rainfall follows the warm water eastward, with associated flooding in Peru and drought in Indonesia and Australia. The eastward displacement of the atmospheric heat source overlaying the warmest water results in large changes in the global atmospheric circulation, which in turn force changes in weather in regions far removed from the tropical Pacific.

Unfortunately, NOAA recently issued an unscheduled EL NIÑO advisory due to El Niño conditions that developed in the tropical Pacific and are likely to continue into early 2007. Ocean temperatures have increased remarkably in the equatorial Pacific during the last two weeks. “Currently, weak El Niño conditions exist, but there is a potential for this event to strengthen into a moderate event by winter,” said Vernon Kousky, NOAA’s lead El Niño forecaster.

During the last 30 days, drier-than-average conditions have been observed across all of Indonesia, Malaysia and most of the Philippines, which are usually the first areas to experience ENSO-related impacts. This dryness can be expected to continue, on average, for the remainder of 2006. Also, the development of weak El Niño conditions helps explain why this Atlantic hurricane season has been less active than was previously expected. El Niño typically acts to suppress hurricane activity by increasing the vertical wind shear over the Caribbean Sea region. However, at this time the El Niño impacts on Atlantic hurricanes are small.

So for the past month I have been on the cutting-edge research that assists physical scientists with data that will create ENSO forecast models to improve our understanding of underlying physical processes at work in the climate system. On our way into Kwajalein, I got to steer the ship. Didn’t go very straight but not bad for my first time. I want to give a HUGE thank you to Commanding Officer Mark Pickett; Executive Officer Robert Kamphaus; Field Operations Officer Rick Hester; the Junior Officers, the science team and the crew of the KA’IMIMOANA for the amazing opportunity I’ve had the honor to experience.

October 30, 2006April 1, 2021

Karolyn Braun, October 30, 2006

NOAA Teacher at Sea
Karolyn Braun
Onboard NOAA Ship Ka’imimoana
October 4 – 28, 2006

Mission: TAO Buoy Array Maintenance
Geographical Area: Hawaii
Date: October 30, 2006

Plan of the Day: Transit to Kwajalein, RMI

Well, we are on our third day of overcast and rain. Our sailing path has taken us into the Intertropical Convergence Zone (ITCZ). The ITCZ is an area of low pressure that forms where the Northeast Trade Winds meet the Southeast Trade Winds near the earth’s equator. As these winds converge, moist air is forced upward. This causes water vapor to condense, or be “squeezed” out, as the air cools and rises, resulting in a band of heavy precipitation around the globe. This band moves seasonally, always being drawn toward the area of most intense solar heating, or warmest surface temperatures. It moves toward the Southern Hemisphere from September through February and reverses direction as the Northern Hemisphere warms during its summer that occurs in the middle of the calendar year. However, the ITCZ is less mobile over the oceanic longitudes, where it holds a stationary position just north of the equator. In these areas, the rain simply intensifies with increased solar heating and diminishes as the sun moves away. An exception to this rule occurs when there is an ENSO event, during which the ITCZ is deflected toward unusually warm sea surface temperatures in the tropical Pacific.

Some crewmembers of the KA’IMIMOANA enjoy some of TAS Braun’s cooking. — Some crewmembers of the KA’IMIMOANA enjoy scrabble

So what else did I do today…well I will tell you! The morning I spent creating a Halloween costume out of duct tape, line, painter’s tape and rags from the Bosun’s locker. It sounds a bit odd I know but it will all come together! After lunch, the afternoon was full of fire drill and abandoned ship drill excitement. During the fire drill, the scenario was that a fire broke out in the aft steering access tunnel. As scientists, we assist the officers in closing vents and act as runners for DC central, Damage Control. Patrick and I had to carry 5-gallon barrels of fire-fighting foam around the ship to the fire fighters, and we had to fetch air tanks as the fire reflashed. Very crazy stuff. When the drill was suspended, the fire fighters were wet head to toe from sweat, shaky and drained from the adrenaline that was flowing through them. At the day’s end, and after a little air drying, I was able to try one of the fire suits on and got a hint of what they go through during a drill or a real fire. The suit was heavy and hot and that was before I had the tanks, mask and helmet on. I applaud anyone who has had the privilege to call himself or herself a firefighter. That evening I made a Happy Halloween banner I hung in the mess while some of the others continued on with game night!

October 29, 2006April 1, 2021

Karolyn Braun, October 29, 2006

NOAA Teacher at Sea
Karolyn Braun
Onboard NOAA Ship Ka’imimoana
October 4 – 28, 2006

Mission: TAO Buoy Array Maintenance
Geographical Area: Hawaii
Date: October 29, 2006

Chief Scientist, Patrick A’Hearn replaces a rain gauge and sea surface salinity sensor on a TAO buoy.

Plan of the Day: Repair TAO buoy 8N/International Date Line and Transit to Kwajalein, RMI

Today was our last TAO buoy of the cruise. I was able to go on the repair and assist the Chief Scientist, Patrick A’Hearn in a rain gauge and a sea surface salinity sensor replacement. Let’s talk TAO buoys.

Development of the Tropical Atmosphere Ocean (TAO) array was motivated by the 1982-1983 El Nino event, the strongest of the century up to that time, which was neither predicted nor detected until nearly at its peak. The event highlighted the need for real-time data from the tropical Pacific for both monitoring, prediction, and improved understanding of El Nino. As a result, with support from NOAA’s Equatorial Pacific Ocean Climate Studies (EPOCS) program, Pacific Marine Environmental Laboratory, (PMEL) began development of the ATLAS (Autonomous Temperature Line Acquisition System) mooring. This low-cost deep ocean mooring was designed to measure surface meteorological and subsurface oceanic parameters, and to transmit all data to shore in real-time via satellite relay. The mooring was also designed to last one year in the water before needing to be recovered for maintenance. In August of 1996, the KA’IMIMOANA was commissioned and dedicated to servicing the TAO array east of 165E.

The TAO surface buoy is a 2.3 m diameter fiberglass-over-foam toroid, with an aluminum tower and a stainless steel bridle. When completely rigged, the system has an air weight of approximately 660 kg, a net buoyancy of nearly 2300 kg, and an overall height of 4.9 m. The electronics tube is approximately 1.5 m long, 0.18 m diameter, and weighs 27 kg. The buoy can be seen on radar from 4-8 miles depending on sea conditions.

Moorings are deployed in water depths between 1500 and 6000m. To ensure that the upper section of the mooring is nearly vertical a nominal scope of 0.985 (ratio of mooring length to water depth) is employed on the moorings in water depths of 1800 meters or more.