upwelling – Page 2 – NOAA Teacher at Sea Blog

April 9, 2008April 2, 2021

Beth Lancaster, April 9, 2008

NOAA Teacher at Sea
Beth Lancaster
Onboard NOAA Ship McArthur II
April 6 – 14, 2008

Mission: Examine the spatial and temporal relationships between zooplankton, top predators, and oceanographic processes
Geographical area of cruise: Cordell Bank Nat’l Marine Sanctuary & Farallones Escarpment, CA
Date: April 9, 2008

Weather Data from the Bridge
Wind – Northwest 20 – 35 knots
Swell Waves – 4-12 feet
Sea Water Temp – 9.4 – 10.5^oC

A 24-hour forecast of sea conditions for April 7, 2008 off the West Coast of the United States. The red section indicates swells that range from 12 to 15 feet. — A 24-hour forecast of sea conditions for April 7, 2008 off the West Coast of the United States. The red section indicates swells 12 to 15 feet.

Reported sea surface temperatures from April 7, 2008 for coastal California from satellite data. The coastal wind did in fact cause an upwelling and cooling of water along the coast. The purple area indicates temperatures 8-8.5oC and the blue 8.6-10oC. — Today’s reported sea surface temperatures for coastal California from satellite data. The coastal wind did in fact cause an upwelling and cooling of water along the coast. The purple area indicates temperatures 8-8.5 degrees C.

The weather reports collected from the bridge of the McARTHUR II reported that the waters traveled over the course of the day did in fact reach 12 feet. The winds from the northwest cause an upwelling effect, which brings deep, nutrient-rich cooler waters to the continental shelf area off the coast of California. This nutrient-rich water plays a large role in the food web of the area, increasing primary productivity, which will then result in large numbers of marine mammals and birds due to the availability of prey items. This period of upwelling in the area of Cordell Bank and Gulf of the Farallones National Marine Sanctuaries marks the beginning of a productive time of year.

Science and Technology Log

Part of the mission on this cruise is to gather oceanographic processes data to look at the relationship between biotic (living) and abiotic (nonliving) factors within the study area. While many samples are being collected through observation and survey equipment outside of the ship, there is just as much being collected in the laboratory onboard the McArthur II. The ship is equipped with several pieces of equipment that report physical features and measurements throughout the day. This information is recorded for scientists onboard to utilize in their data analysis. The following is a list of equipment, and their functions being used to measure oceanic processes:

Thermosalinograph (TSG) – Surface water is pumped from the ocean through a hose to this piece of equipment which measures temperature and salinity. There is an additional probe that measures CO2. All information collected during the course of the cruise will be given to researchers to use in data analysis.

Scientific Echosounder – Sends a sound wave into the water column. If there is anything in the water column this sound wave will reflect back to the ship. The longer it takes for the reflected wave to get back to the ship the farther away the target is. Comparing three different frequencies emitted by the echosounder allow scientists to identify different types of plankton in the water column, and set sampling sites.

Navigation Software – Allows researchers to track where they have been and where they are going. Because nets and other equipment are being deployed from the ship this computer software allows scientists to view the charted underwater topography to determine placement and depth of equipment. By marking sample sites using the software, scientists can look at the relationship between the ocean’s topography and living organisms collected.

NOAA Teacher at Sea Beth Lancaster (left) and NOAA Chief scientist Dr. Lisa Etherington (right) view sampling areas using navigation software in the McARTHUR II’s dry lab. — NOAA TAS Beth Lancaster (left) and NOAA Chief scientist Dr. Lisa Etherington (right) view sampling areas using navigation software in the McARTHUR II’s dry lab.

Personal Log

I have been onboard the McARTHUR II for four days, and have enjoyed every minute of helping out with the research project. Scientists have been so patient and willing to answer all of my questions. The crewmembers onboard the McARTHUR II are very friendly and helpful. I now have a much better understanding of the marine physical environment than I did upon my arrival! I am enjoying living at sea, even the small bunks! The ship is actually very large you would never know there were more than twenty people onboard!

Animals Seen Today

Black-footed Albatross, Pteropod, Pigeon Guillemot, Copepods, Brandt’s Cormorant, Ctenophore, Sooty Shearwater, Krill, Northern Fulmar, Microscopic Plankton, Black-legged Kittiwake, California Gull, Western Gull, Common Murre, Cassin’s Auklet, Rhinoceros, Auklet, and Bonaparte’s Gull.

April 7, 2008April 2, 2021

Beth Lancaster, April 7, 2008

NOAA Teacher at Sea
Beth Lancaster
Onboard NOAA Ship McArthur II
April 6 – 14, 2008

Beth Lancaster (right) preserves a plankton sample collected using a hoop net. — NOAA Teacher at Sea Beth Lancaster bottles a surface water sample that will be tested for the presence of nutrients.

Science and Technology Log

Today was the first full daytime operations. We began shortly after 7:00 a.m., and covered a 90 kilometer transect throughout the course of the day ending at 6:00 p.m. At each sampling point along the transect a series of measurements and observations were made to look at relationships between the physical ocean environment, and abundance of living organisms that are observed and collected to gain a better understanding of the physical and biological features of the area, and how they interact. The daytime crew was divided into two groups: the marine mammal and bird observers, and a second group that was responsible for collecting water and plankton samples as well as other various physical measurements of the water. I worked with the second group, and will share what sampling I assisted with.

At each sampling point we used the CTD, which is a piece of equipment that has several probes on it, to collect a vertical sample of the water column. When the CTD is deployed into the water it is sent down 200 meters below the surface and collects water conductivity (used to calculate salinity), temperature, depth, and turbidity. There is also a fluorometer attached to the CTD that measures the fluorescence of chlorophyll-a, which approximates the abundance of phytoplankton. The CTD collects all this data, and can then be downloaded onto a computer. Surface water samples were also collected at each sampling point, and will be tested for the presence of nutrients which would also have a direct impact on the abundance of organisms in the area.

To gather information on the living organisms present at each site, a hoop net was used to collect samples of plankton. The net was sent down approximately 50 meters, and collected all of the tiny living organisms (zooplankton) on a screen as the net was pulled through the water column. When the hoop net was brought back onboard, the cod end of the net (where the sample is collected) was transferred to a sample bottle, and preserved for further investigations in the laboratory. In addition to the living organisms collected in the hoop net, marine mammal and bird observations are being made from the flying bridge of the ship. That would be the highest point on the boat, and not the location for people who are afraid of heights. Due to rough sea conditions (10-12 foot swells), sightings were few and far between today. Springtime within Cordell Bank National Marine Sanctuary is a time where strong winds cause upwelling of deeper waters towards the surface near the coast. This upwelled water is colder and has higher nutrient concentrations.

Sample of krill caught in the daytime with a hoop net.

This influx in nutrients means the ecosystem becomes very productive. Given this high influx of nutrients, prey items for birds and mammals are readily available. The food of choice for a lot of these organisms is krill (a shrimplike zooplankton.) We did collect some krill in the hoop net during the day, but the abundance of krill in shallower water is much greater in the evening, when krill migrate from deep depths towards the surface. The night crew is collecting krill using a tucker trawl, which has three separate nets that are opened and closed at different depths. Krill play a vital role in the ecosystem scientists are currently studying. They provide nourishment for resident and migratory birds as well as marine mammals. There is sufficient nutrient availability for primary producers which are then food for primary consumers such as krill, and therefore food availability for secondary consumers such as fish and tertiary consumers such as whales and dolphins.

Throughout the week the same measurements will be taken at different sights along the continental shelf and continental slope in the region of Cordell Bank National Marine Sanctuary and the Farallones Escarpment (within Gulf of the Farallones National Marine Sanctuary). This information will allow scientists to better understand the dynamic relationship between zooplankton, top predators, and oceanographic processes. Data gathered will also be used in conservation planning of the marine sanctuaries.

Some Animal Sightings
Black-footed Albatross, Ancient Murrelet, Northern Fulmar, Laysan Albatross, and Pacific White-sided Dolphin.

October 18, 2005March 18, 2021

Eric Heltzel, October 18, 2005

NOAA Teacher at Sea
Eric Heltzel
Onboard NOAA Ship Ronald H. Brown
September 25 – October 22, 2005

Mission: Climate Observation and Buoy Deployment
Geographical Area: Southeast Pacific
Date: October 18, 2005

Weather Data from Bridge

Temperature: 25.5 degrees C
Clouds cover: 6/8, stratus, altocumulus
Visibility: 12 nm
Wind direction: 245 degrees
Wind speed: 13kts.
Wave height: 3 – 5’
Swell wave height: 3 – 5’
Seawater Temperature: 28.7 degrees C
Sea level Atmospheric pressure: 1005 mb
Relative Humidity: 82%

Science and Technology Log

Rodrigo Castro and Carolina Cisternas are research technicians from the University of Concepcion in Concepcion, Chile. They joined the cruise at Panama City and have been taking ocean water samples every 60 nm. Their samples are run through 0.7 and 0.2 micron filters. They capture and freeze particulate organic mater by this process and take it back to the lab at the university. The samples are analyzed for the presence of stable isotopes of carbon and nitrogen. These samples are then used as biomarkers to help determine the circulation of ocean water. A second analysis will be going on to locate the gene associated with nitrogen-fixing organisms. This is new ground for the scientists at the university.

Upwellings are areas where deep ocean water comes to the surface. According to Rodrigo and Carolina there are four significant areas of upwelling along the Chilean coast. The two most northerly are found at 20 degrees south and 24 degrees south. These are active year round and are slow and steady with no significant seasonal fluctuation. Another at 30 degrees south is moderate in nature with some seasonal variation, being more active during the summer. The most southerly is at 36 degrees south and is strong September to April. However it mostly disappears the rest of the year. Upwelling zones are recognizable because of their cooler water temperature. They also have increased nutrients that are brought up from the deep and a higher amount of chlorophyll due to increased photosynthetic activity. Some fish species are found in greater abundance in these zones due to increased nutrients extending into more food availability.

Personal Log

The RONALD H. BROWN is under way. We are steaming in an easterly heading on the leg of the cruise that will take us to Arica, Chile. It is a bit of a challenge for me, as we are no longer headed into the direction of the swells; instead, we are crossing them at a 30-degree angle, which makes for more oscillations in the movement of the ship. My tummy is being challenged.

October 5, 2005March 18, 2021

Eric Heltzel, October 5, 2005

NOAA Teacher at Sea
Eric Heltzel
Onboard NOAA Ship Ronald H. Brown
September 25 – October 22, 2005

Mission: Climate Observation and Buoy Deployment
Geographical Area: Southeast Pacific
Date: October 5, 2005

Weather Data from Bridge

Temperature: 19.5 degrees C
Sea level Atmospheric pressure: 1010 mb
Relative Humidity: 90.5%
Clouds cover: 8/8, stratocumulus, altostratus
Visibility: 9 nm
Wind direction: 230 degrees
Wind speed: 6kts.
Wave height: 3 – 4’
Swell wave height: 3 – 5’
Seawater Temperature: 19.5 degrees C
Salinity: 34.7 parts per thousand

Science and Technology Log

Notice that the seawater temperature declined from 28.7 to 18.8 degrees C between yesterday and today. We crossed the equator last night so this must have something to do with it. I went to Doctor Weller and asked for an explanation:

At this latitude and at this season we are still under the influence of the southeast Trade Winds. Wave motion generates and moves at 90 degrees to the wind direction. Now the Coriolis Effect comes into play causing waves to deflect to the left in the southern hemisphere. That means that the prevailing wave direction is from northeast to southwest south of the equator.

As the winds move into the northern hemisphere wave movement is still at 90 degrees. However, now the Coriolis Effect causes waves to deflect to the right, from southwest to northeast. So this time of year the wave motion in the two hemispheres is 180 degrees to one another. As the surface waters move apart, deeper ocean water comes to the surface to fill the area evacuated by the surface wave motion. This water is coming from greater depths and is colder. This accounts for the lowering of the seawater temperature. Dr. Weller suggests that this action brings nutrients to the surface which should enhance feeding opportunities for marine life.

Vertical and horizontal motion of ocean water causes constant exchanges of heat energy. These exchanges are between water of different temperatures and also the atmosphere. Currents, waves, upwelling, evaporation, and winds are just some of the factors that influence heat exchanges on planet earth. These processes are critical to maintaining global climates. Dr. Weller’s Upper Ocean Processes Group seeks to better understand these relationships.

Ship Crew Activity

I went to the Bridge this morning to gather weather and sea condition data. The Officer of the Deck was LTJG Silas Ayers and the Watch Stander was Ordinary Seaman Phil Pokorski. The Bridge Officer always has a crewmember with them whose job it is to be lookout to scan the ocean and report what can be seen. This could be another ship, debris, or whales. The crewmember takes a sighting and determines the distance and bearing. Avoiding collision is an important job for the Officer of the Deck.

While there, the three of us engaged in a discussion of nautical measurements and their equivalencies. LTJG Ayers went to the Chart Room and extracted a reference book. Here are the values we found:

Fathom = 6 feet, 2 yards, 1.8288 meters

Cable = 720 feet, 240 yards, 219.4560 meters

Statute Mile = 5280 feet, 1760 yards, 1609.344 meters

Nautical Mile = 6,076.11548556 feet, 1852 meters, 1.150779448 statute miles

League = 3 statute miles, 4830 meters

(As in 20,000 Leagues under the Sea)

Being a Jules Verne fan, I’ve often wondered how far 20,000 leagues really is. Now I know that it is 60,000 statute miles. But nowhere is the ocean nearly that deep. Phil then pointed out that Verne was referring to horizontal distance traveled while submerged in the Nautilus. Finally the title of his tale makes sense to me.

Personal Note

Starting last evening I was hearing a squeaking sound. At first I thought it was my deck shoes squeaking on the tile deck floors. Then I notice that even when I wasn’t moving the sound persisted. I was beginning to wonder if being at sea and wearing a motion sickness patch wasn’t causing me to be hallucinatory. I looked and looked for the source of the sound. I finally asked Dr. Weller if he could hear it and fortunately he said yes. It is the sound generated by the Sea Beam, the ocean floor profiler. I was relieved to know that if wasn’t just me hearing this sound.

May 16, 2004March 18, 2021

Geoff Goodenow, May 16, 2004

NOAA Teacher at Sea
Geoff Goodenow
Onboard NOAA Ship Oscar Elton Sette
May 2 – 25, 2004

Mission: Swordfish Assessment Survey
Geographical Area: Hawaiian Islands
Date: May 16, 2004

Time: 1615

Lat: 18 25 N
Long: 156 13 W
Sky: A dreary morning with gray stratus clouds all around and an occasional misting of precipitation. Much brighter sky by 1300 — enough to cast shadows, but remained mostly cloudy throughout the day. A pleasent evening with clearing skies.

Air temp: 25.7 C
Barometer: 1011.61
Wind: 352 degrees at 13 knots
Relative humidity: 71.5%
Sea temp: 26.4 C
Depth: 5012.1 m
Sea: 2-3 foot swells

Scientific and Technical Log

Longline retrieval started on a bad note this morning as the line went under the ship. It caused only a short delay as maneuvers were quickly and successfully made to keep it out of the propellers. We brought up an escolar, 2 snake mackeral, and a broadbill swordfish head. A large, angry silky shark came in also. The shark was released after being tagged and “kindly” relinquishing a remora. And finally, a new species for the record, a lancetfish (Alepisaurus ferox). These guys look much like the snake mackeral, a long thin body up to 200cm, nearly cylindrical with a tall uneven dorsal fin (sail)standing perhaps 5 body widths high over nearly 2/3 of its back. The snake mackeral’s dorsal fin does not rise nearly so much. The lancet’s skin was very smooth, scaleless in fact, iridescent and rather pale. They have narrow snout with long sharp teeth.

For those interested in the studies of pelagic fishes, the Pelagic Fisheries Research Program (PFRP) publishes a newsletter which can be viewed online (I think) at http://wwwsoest.hawaii.edu/PFRP . For more on the eye work being done by Kerstin and others see Vol. 6 Number 3 (July-September 2001).

Other studies aboard the SETTE:

Melissa is a master’s program student at Virginia Institute of Marine Sciences (VIMS). She did her undergraduate study at UC San Diego. She has been collecting remoras, larvae from our plankton tows and stomach contents from some fishes, and fin clips from sharks. Here’s what it’s all about:

The remoras are being collected as a favor for her labmate’s work at VIMS. That person is looking at the phylogenetics of remoras and also that of their hosts which include sharks, billfishes, and the occasional baitfish or float. She is also collecting fin clippings from sharks of the genus Carcharhinus (e.g. oceanic white tips, silky sharks) for another labmate working on the sandbar sharks (also in the Carcharhinus genus) off of Virginia, looking at natal homing patterns.

From the plankton tows, Melissa is interested in larvae of the fish family Scombridae which incldes tunas, wahoo, bonitos, and mackeral. Can we find ways to identify them based on their genetics? Samples from all will be sequenced using their mitochondrial DNA in an attempt to find unique interspecific (between species) genetic markers. The value of this is that it would allow easier identification of larval types than does morphological identification. We might more readily then identify where and when particular species spawn and thereby attain a better understanding of their life histories. Are the genetics of a species uniform throughout the range of the fish? If there are significant genetic differences in populations then perhaps it is wise to manage fisheries of that species by area as opposed to globally (one size fits all approach) so as to preserve gene pool diversity. Answers to these questions could lead to management practices that better protect these resources.

This work also has applications in forensic studies. Fish that have been taken illegally and already filleted can be identified by genetic markers enabling better enforcement of regulations. Also, morphological identification of degraded tissue, as in stomach contents where enzymes have done their deed, is impossible. Stomach contents collected here will be screened using genetic markers for the tuna larvae to see if the larvae are part of that particular fish’s diet. Applications from this work could potentially aid studies of trophic levels and predator/prey relationships.

Goodenow 5-16-04 shark on cradle — Shark being lifted aboard

Personal Log

Suffered my first injury in shark wrestling today with a slight abrasion to left knee — not enough to scare me away from the next match. Nothing too news worthy to report about the day. It was a rather slow day. Not much sun, humidity was above the norm — a bit uncomfortable outside. Continued reading Wilson’s book, did wash and stewards offered a linen change today which I took advantage of.

There was a moment of excitement this afternoon when a marlin took off with a troll line. It was out of control and our two champion fisherman couldn’t handle it. Gears were stripped in the reel which actually smoked from the heat generated as line spinned off. That rod is out of action for the duration; the fish won that round.

This evening our electronics technician, John, gave me a pictorial introduction to other research cruises of the SETTE which I will share with you another time. And, relieved of longline duties tonight, I spoke with Mike and science in general and some specific regarding his work in fisheries research.

To all of my ’02-’03 Advanced Biology students, I am sorry to report that I was not able to make use of my Secchi disk nor did I even see one on the ship.

Question:

What does the term upwelling mean? Identify several general locations in the oceans where upwelling occurs. What is the biological impact of upwelling in those areas?

Geoff