Warm Water and Poisoned Clams, What’s Happening off our Coast?

Wednesday, July 8th, 2015

greatwhiteinAptosWhat do Great White shark sightings near Santa Cruz, a toxic algae bloom from Santa Barbara to Seattle and the collapse of the salmon fishery have in common? They might all trace to a persistent blob of warm water that has been clinging to the west coast since last year, according to research conducted by NOAA and others.


It’s a complicated story, so I’ll try to unpack things with the help of Nate Mantua, a climate scientist based at NOAA’s Southwest Fisheries Science Center in Santa Cruz. First of all, the warmer-than-normal water has been with us since early 2014, but has been getting stronger and growing. From this map,

Daily ocean sea surface anomaly from July 7, 2015

Daily ocean sea surface anomaly from July 7, 2015. Dark red areas show higher than normal ocean temperatures.

which shows temperature anomalies, or the areas where temperatures are warmer or colder than expected, you can see a very warm finger of water off Peru as well as warm patches of water extending into the Pacific between the West Coast and Hawaii and even up into Alaska. This warm water has brought with it lots of marine species that prefer the tropics this time of year, from sharks in Santa Cruz to pygmy killer whales seen for the first time off California last winter.


As Nate explained to me, each of these warm regions reflects persistent changes in atmospheric pressure, wind and ocean current patterns. Some of the changes are associated with El Nino, the periodic warming of the Eastern Pacific Ocean off South America that shifts weather patterns and could bring heavy rainstorms to California this winter, which would be a welcome relief to our drought-stricken state. But the warm water anomaly started last year, before this El Nino developed and grew, and is likely the result of large-scale shifts in atmospheric pressure resulting in weaker winds from the north. These winds, which typically strengthen in springtime, would normally push sun-warmed surface water off shore and bring up cold, nutrient-rich water from below, a phenomena known as upwelling.


Tiny marine invertebrates called copepods are critical components of the coast marine food web

Tiny marine invertebrates called copepods are critical components of the coast marine food web

Upwelling is an important feature for marine ecosystems all along the west coast. The cold, nutrient-rich waters support a bloom of phytoplankton, plant-like marine algae that thrive in upwelling conditions and support an entire rich food web from marine invertebrates called copepods to fish, seabirds and even whales. A highly productive salmon fishery depends on upwelling and fat, juicy copepods to feed the young fish as they travel from streams to the ocean. When upwelling is diminished, as a NOAA report warns is happening this year, young salmon can take a hit and never grow up to be big salmon for fishermen to catch.


Upwelling also affects the balance of marine algae along coastal regions. When nutrients are present, the “good“ algae species dominate the ecosystem. When the regime shifts to warmer, nutrient-poor conditions, “harmful” or toxic algae can gain a foothold and proliferate. This spring and summer, a toxic algae bloom has spread from Santa Barbara to Alaska to become the most severe in nearly two decades, according to Raphael Kudela of UC Santa Cruz whose lab helps monitor and map harmful algal blooms in California.


The harmful marine alga, Pseudo-nitzschia produces domain acid, a neurotoxin that can harm marine life

The harmful marine alga, Pseudo-nitzschia produces domoic acid, a neurotoxin that can harm marine life

The algae in this huge bloom, called Pseudo-nitzschia, produces domoic acid, a neurotoxin that accumulates in filter feeders, such as clams and mussels, and species lower in the food chain, such as crabs, anchovies and sardines which feed on plankton. The concentrations of domoic acid detected in Monterey Bay and along the coast of Oregon and Washington are some of the highest ever recorded and has resulted in the closure of shellfish harvesting and warnings about consuming recreationally-caught mussels, clams, and the internal organs of crabs taken from Monterey and Santa Cruz counties.


So while you might enjoy taking a dip in the ocean sans wetsuit this summer, this is all a good reminder that ecosystems and climate are intimately connected and that large changes in winds, ocean currents, and temperatures can have profound, long-term effects on marine life and communities that enjoy and depend on healthy oceans.

Weird Weather: California’s Dry, Hot Year

Tuesday, February 3rd, 2015

We’ve just gone through the driest January in recorded history in San Francisco. That record is likely to stand, since we didn’t get a drop of rain last month and you can’t get any drier than that. Of course, a complete lack of rainfall is bad news for the ongoing multi-year drought, but it’s not the only weird weather we experienced. I went to a talk recently by Nate Mantua, a climatologist for NOAA, based at the Southwest Fisheries Service Center in Santa Cruz. temperaturerecordsNate showed data records (right) that put 2014 as the hottest it’s been in more than a century. All but a few days last year were each warmer than the average daily temperature in nearly all locations in the state.

It should be said that this unusual warmth was experienced throughout the southwest, centered in California, although large swaths of the midwest and east coast had cooler than normal temperatures last year.

So what’s going on? Certainly global warming, or as some people call it “global weirding”, is disrupting our climate patterns. But it wasn’t just the land, the Pacific Ocean also behaved strangely last year.


The Pacific has a strong influence over weather, especially for those who live near the coast. In the late spring and early summer, ocean temperatures are generally cool and that cool water can generate fog and chill winds that provide natural air conditioning to the Bay Area. But last spring, sea surface temperatures from Baja California to Alaska were one to two degrees warmer than typical (there were days last year when the water was nearly warm enough in Monterey and San Francisco to swim or surf without a wetsuit). Whether the warming over the last year is a sign of larger patterns in Pacific Ocean temperatures remains to be seen, but scientists are keeping an eye on it.












The warm water brought with it a myriad of tropical marine species off the coast, including mola mola (aka sunfish) and plenty of jellies caught in the summer research cruise conducted by NOAA’s Southwest Fisheries Science Center.

Going Deep in Belize: Aboard the Exploration Vessel Nautius

Thursday, August 14th, 2014

August 12, 2014 Turnieffe Reef, Belize

The E/V Nautilus on the Meso-American Reef off Belize

The E/V Nautilus on the Meso-American Reef off Belize

I’m sitting in the lounge of the Exploration Vessel Nautilus listening to the control room chatter and watching the video feeds from the ship’s two ROVs, Hercules and Argus, as they explore the sea floor off the coast of Belize (you can follow along on expeditions as well on the Nautilus Live website). It’s hurricane season in the Caribbean, but thankfully the weather has been fair and balmy and the sea calm. We’ve been on a mission to map and explore the deep parts of the Meso-American reef, the second largest coral reef system in the world after Australia’s Great Barrier Reef. The depths here have never been explored before this expedition and hopes were high that we’d find a lot of deep-water coral communities (and maybe a ship wreck or two).

But what’s abundant in the sun-lit surface waters off the central American country of Belize seems to be rare in the dark depths and we haven’t come across as many coral communities as hoped. That’s due in large part, according to scientists on board the ship, because of a lack of hard surfaces for the corals to settle on and grow.  Unlike shallow-water coral which host an algae garden in their bodies to help nourish them, deep sea corals must capture food that streams past their tentacles.  That means they need to cling to rock, not sediment, to keep from getting blown away in the current.  Unfortunately,  sediment is what we’ve been seeing a lot of,  covering the bottom and most of the rocks we see as Hercules (or “Herc”) motors from target to target along the muddy sea bottom.

Peter Etnoyer processing samples in the wet lab.

Peter Etnoyer processing samples in the wet lab.

That doesn’t mean this expedition has been a bust. The chief scientist on the cruise, NOAA’s

Deep sea coral with shrimp still clinging to its branches

Deep sea coral with shrimp still clinging to its branches

Peter Entnoyer, has been having the ROV pilot grab samples of corals, sea urchins, crinoids (related to sea stars), sponges, and some small crabs and squat lobster clinging to the larger invertebrates.  It’s a tricky task for the pilot, who controls a joystick sending commands through a fiber-optic cable to manipulate the Herc’s arms which are charmingly named Predator and Mongo. For some of more delicate critters like the lemon-yellow tentacled creature we spied earlier today, the pilot uses a slurper tool, but that proved a bit too forceful for the gelatinous snail and I fear it’ll be bits and pieces when Peter pulls it out of the ROV sample box.

This unknown deep sea organism had bright yellow fringes that were lost during collection.

This unknown deep sea organism had bright yellow fringes that were lost during collection.

We found out later that what looked underwater like a nudibranch (a kind of shellless, fringed snail),  looked more like a worm when it came up sans the yellow tentacles. It’ll take experts back on shore time to determine what this organism really is as none of the scientists who tuned in had ever seen anything like it.

As soon as Herc comes back on deck, the invertebrates are removed from the boxes with forceps and brought into the lab. After a sample is snipped off and placed in fixative for later genetic analysis, the organism is laid out on a table to measure and photograph. The other night, a crynoid collected 500 meters below the surface was still waving its arms around when placed on the lab table to the amazement of those of us gathered in the ship’s wet lab. After the biologists here have finished examining and logging the samples, they’ll be placed in bags with alcohol for shipment to Harvard’s Museum of Comparative Anatomy and other labs around the country.   Experts “on the beach” will study the corals and other invertebrates and do genetic typing to determine whether any are new, undiscovered species. Peter thinks this is a good possibility since deep-sea corals are little studied and specimens have never been gathered from this part of the deep Caribbean before. That would be a thrill for me, having seen first-hand the discovery as it happened.

Our carbon buoy gets a makeover

Saturday, July 26th, 2014
The NOAA CO2 buoy measures carbon content in the bay and atmosphere at Pier 15.

The NOAA CO2 buoy measures carbon content in the bay and atmosphere at Pier 15.

July 25, 2014

Since the Exploratorium opened at its waterfront location more than a year ago, we’ve been engaged in a unique experiment with the National Oceanic and Atmospheric Administration. NOAA’s  Pacific Marine Environmental Lab in Seattle lent us a beautiful ocean buoy, outfitted with instruments to measure carbon in the ocean and atmosphere. For the last 15 months, it’s been bobbing in all its white and red glory in the lagoon between Piers 15 and 17, occasionally surrounded by mist from the fog bridge art piece.

Instruments mounted on the buoy have been gathering oceanographic and atmospheric data to help scientists understand how the build-up of carbon dioxide in the atmosphere and ocean affect marine ecosystems. Ours is the only one of NOAA’s CO2 buoys so close to an urban center and a major estuary, both of which add carbon to the bay water. The unusual chemistry of San Francisco bay waters can be a living laboratory for the future, when marine environments become increasingly more acidic (more on that in a later post).

Operations chief Chuck Mignacco steadies the angry bathtub while Chris Raleigh looks on.

Operations chief Chuck Mignacco steadies the angry bathtub while Chris Raleigh looks on.

We’ve reached a milestone with the experiment, the first time we’ve pulled the buoy out of the water for maintenance. It’s a complex choreography of forklift, mobile crane and a balky metal watercraft dubbed “the angry bathtub” to lift the one ton buoy from the water onto our outdoor plaza. Over the next week, our marine technician, Chris Raleigh, will be swapping out and calibrating instruments, scaping off marine growth and repainting the faded red striping all in view of the public.

I was excited to get a look at what’s been growing below the buoy’s water line and woke early to get down to the Exploratorium and document this momentous occasion. As expected, the bottom of the buoy was covered in leafy green and lacy red algae, with some mussels,

After 15 months in the bay, the bottom of the buoy is covered with marine life.

After 15 months in the bay, the bottom of the buoy is covered with marine life.

bryozoans and limpets in between the plants. We even found a few oysters and a small scallop. The shells of the mussels and oysters were very fragile and broke apart in my fingers, quite unlike the thick-shelled tide pool mussels I’m used to handling. I wonder if this could this be from the higher acidity of the water or the fact that these shellfish are protected from wave action.

We even saw growth on the chain floats: solitary stalked tunicates attached along with the slimy colonial tunicates, mussels and osyters. Crawling all around were crabs, segmented worms (which resemble aquatic centipedes), ghost shrimp and some tiny iridescent shrimp of the brightest lime green I’ve ever seen. We took samples and plan to share them with scientists who study invasive and native organisms of the bay.

Just about any surface exposed to bay waters will be colonized with all manner of colorful invertebrates and algae.

Just about any surface exposed to bay waters will be colonized with all manner of colorful invertebrates and algae.

The buoy will be out of the water for a week, getting its yearly make-over before we lift it back into the bay to start collecting live data once more. In my next post, I’ll discuss what we’ve learned from the carbon and oceanographic data we’ve gathered over the last 15 months.

The Ocean’s Carbon Problem: Investigations in San Francisco Bay

Tuesday, September 10th, 2013

Right after we moved the Exploratorium to its new waterfront location, we got a gift from NOAA’s Pacific Marine Environmental Lab in Seattle: a beautiful red-and-white ocean buoy. Normally, these buoys are deployed out at sea to measure dissolved and atmospheric carbon dioxide, but we got to put one right in the lagoon between piers 15 and 17.

Accumulated CO2 in the Atmosphere and Ocean NOAA

Since the beginning of May, the buoy has been collecting CO2 data from the bay waters and the atmosphere in San Francisco and we’ve noticed some interesting patterns in the read-outs. First, it might help to know why we care about dissolved CO2. Carbon dioxide is constantly exchanged between air and water; when atmospheric CO2 levels increase, more of the gas is absorbed by ocean. The increase in dissolved CO2 is increasing the acidity of the ocean, an effect called ocean acidification. Since the start of the industrial age, the ocean has absorbed 30% of the CO2 produced by the burning of fossil fuels, changing the chemistry of the ocean. These chemical changes can have harmful effects on the biology of marine organisms that build shells, including oysters, plankton, and a marine snail called a pteropod, which in turn affect food webs and marine ecosystems.

We see higher levels of dissolved carbon dioxide in San Francisco Bay than offshore in part because urban areas are sources of atmospheric CO2 but also because our location is influenced by both the open ocean outside the Golden Gate and the freshwater estuary in the South Bay. Estuaries typically contain more dissolved CO2 because they have higher levels of organic matter than the open ocean. When organic matter decomposes, it releases CO2 into the water. At Pier 15, we see a decrease in the dissolved CO2 and sea surface temperature (SST) and an increase in salinity as the tide rises and brings in cold salty and less acidic water from the Pacific. As the tide falls, estuary waters flow in from the south bay and the CO2 levels go up, while temperature increases and the salinity goes down. That’s why you see this daily zig-zag in the data.

This shows the dissolved CO2 (above) and oxygen (below) from the buoy at Pier 15.

The data also shows a longer two-week pattern of decreased levels of dissolved CO2 corresponding to an increase in dissolved oxygen. We think the increased oxygen is from a bloom of phytoplankton which take up carbon dioxide (decreasing the dissolved CO2 levels) and release oxygen (increasing the O2 levels) as they grow. I heard from scientists at Bodega Marine lab that this bloom also corresponded to an upwelling event off the coast which brings cold, nutrient-rich waters from the deep up to the surface feeding the phytoplankton bloom. This is similar to what happens with atmospheric carbon dioxide in the summer. As plant life grows in the summer it absorbs CO2, causing a temporary dip in the levels of atmospheric carbon dioxide. In the winter, plants shed their leaves which decay and release CO2 into the atmosphere, creating a yearly zig-zag in the gas levels.

The CO2 buoy is part of our Wired Pier project which places scientific instruments and sensors in the water and on the roof of Pier 15. In the coming months we’ll post more of these data stories, but you can access the current real-time feeds and other locations at

Coming Into Port

Sunday, August 4th, 2013

Research Vessel Thomas G. Thompson at sea. Credit: UW

The Tommy Thompson, as it’s affectionately known, is heading back to Newport, Oregon to get ready for the next and final leg of this summer’s construction project for the regional cabled observatory. If all goes as planned, by mid-August they’ll have installed all the observatory’s secondary subnets at the Axial volcano and tested the cables and instruments, including an HD video camera. But, as chief scientist John Delaney says, with oceangoing research, plans are just the starting point. Weather, equipment failures, and occasional human error all factor into a continually evolving set of activities, more like jazz improvisation than a symphony orchestra.

This leg started with some setbacks, from a lost day at port fixing an electrical problem with the ship’s thrusters to being blown out on the first dive by ocean swells at the continental Slope Base. Once we got to Axial though, the team got into a rhythm of laying and testing cable, installing instruments and collecting data, the latter of which provided perhaps the expedition’s most joyous moment when two seismometers detected and recorded an earthquake. On the same 36-hour epic dive, however, we all learned a new term, “hockle.” A hockle is a kink in the electro-optical cable and a few of them were discovered in a cable, which testing showed had restricted its ability to carry data and power. The engineers will do more testing on the next leg and may need to replace some of the damaged cable. Despite those hiccups, the observatory construction work ended on a high note with a successful cable lay at Slope Base where the sea was almost glassy compared to earlier in the expedition. Throughout the cruise, the deck of the R/V Thompson was cleared of bright orange cable as ROPOS reeled out a total of 16 km on the ocean floor.

Over the last two weeks, the scientists also tried out new instruments including a temperature and salinity probe placed right into an extremely hot hydrothermal vent and a bottom-pressure tilt meter that will measure the movement of magma under the volcano. Co-chief scientist Giora Proskurowski deployed a reinforced collection bottle that can bring up a high-pressure gas sample from a hydrothermal vent for testing in the ship. It was exciting to look over Giora’s shoulder until the moment when he released some of the vent’s sulfurous gas, which immediately filled the room with the stench of rotten eggs. He calls it the smell of success, but I beat a hasty retreat.

The expedition was ahead of schedule going into yesterday, so the team was able to do an oceanographic favor for some colleagues in need (on the order of, “since you’re in the neighborhood…”). John Delaney was asked by geologists at Woods Hole Oceanographic Institute (WHOI) to recover a couple of seismometers that didn’t answer to pings and rise to the surface when signaled. (Underwater instruments commonly have an electronic recovery system that, when activated by a ship signal, engage flotation devices. These two prodigal seismometers, placed in different locations, didn’t come home when called). So we set off to the south on a search and rescue mission to find a couple of lost yellow boxes on the bottom of the ocean.

The dive planners didn’t know exactly where the boxes landed so they devised an ROV search pattern that started close to the sites where each seismometer was dropped. It proved unnecessary with the first yellow box, because ROPOS landed almost on top it and clamped on within five minutes of reaching the bottom. The second seismometer proved more difficult. We steamed to the spot described by the WHOI scientists, but the location had brisk winds and a strong current that made it very difficult for the ship to remain on station above the ROV. After one attempt and some waiting, John Delaney decided it served nobody’s interest to jeopardize ROPOS so we gave up on the second seismometer and started our 15-hour steam back to Newport.

Spending two weeks at sea on a history-making project, which this real-time ocean observatory will surely prove to be, is an incredibly immersive, exhausting and exhilarating experience. Part of my job here was to share the experience and the science I was learning along the way. We did some live ship-to-shore programs with audiences at the Exploratorium, experimenting with ways to activate an exhibit space with a distant research project. In the long term, we hope to find ways to connect the Exploratorium’s Bay Observatory, with its own complement of real-time oceanic and atmospheric sensors, to the regional cabled observatory in ways that would let people explore the data, ask questions and find connections between the deep sea and coastal locations.

Under the Sea, Down in the Muck

Saturday, August 3rd, 2013
Whales off coast of Oregon

credit: Mary Miller

One of the ship activities I enjoy most is watching the ROV ROPOS descend through the water column so I can do some wildlife viewing along the way. Of course, you don’t need an ROV to observe animals at sea. We’ve been seeing plenty of albatross throughout this expedition and have been visited by whales the last couple of days once we moved closer to shore.

But the creatures you glimpse as you descend to the deep are rarely, if ever, seen near the surface and many are adapted to life in the cold and dark. They often have large eyes and languid locomotion as befits an environment that has scarce resources, light and activity.

The first 200 meters or so is the photic zone, the region of the ocean where light penetrates and photosynthesis dominates the food chain. Jellyfish are often spotted here and the water can appear cloudy and full of white flakes and jelly-like particles, commonly known as “marine snow.” I was lucky enough to study at UC Santa Cruz with Mary Silver, a plankton specialist who was a pioneer in the study of marine snow. Before she focused on it, most marine biologists considered the non-living flocculant material an annoyance that clouded the ocean and fouled their net samples. But in the 1970s, Mary started sampling marine snow and discovering the true nature of this material. What she found was a complex stew of discarded larvacean houses*, dead organic material, and the general debris and detritus of the marine ecosystem, much of it teeming with bacteria and other single-cell organisms… in other words a potential food source for larger animals. By nibbling on marine snow, fish and other grazers can receive a nutritious meal that would otherwise be too diffuse and small for them to consume directly.  Eventually this organic-rich material sinks to the sea floor to be picked over by the resourceful bottom creatures we’ll soon see when ROPOS arrives there.

Nudibranch swimming through the water columnAs we descend beyond the sunlit surface waters, the cameras and lights on ROPOS let us peer into this little-known realm. A nudibranch undulates like a synchronized swimmer past the camera and then we spy one of our distant relatives, a solitary salp. A model of ocean efficiency, the salp looks like a jellyfish but it’s actually more closely related to humans and other vertebrates. It moves by pumping water through its body, filtering the seawater and extracting a meal at the same time.

After 90 minutes or so of descent, we reach the bottom with its compliment of crawling, swimming and sedentary creatures. The fish known as rattail dominates the swimming creatures while brittle stars–mobile, long-legged scavengers–populate the mud and rock bottom. Spider crabs are also frequent visitors. Attracted by vibrations, they come around to investigate ROPOS and the equipment surrounding it.

But my absolute favorite is the octopus. This is the intelligentsia of invertebrates, with complex eyes, large brains and fast reflexes.  They don’t seem disturbed by the invasion of lights and equipment of the ocean observatory, some will even act as ad-hoc inspectors of the cables.  I never get tired of watching their antics, whether it’s the Graneledone pacifica crawling with nimble arms across the bottom or the aptly named Dumbo octopus we see swimming in the water column as ROPOS makes it way back up the ship.

*Larvaceans, small tadpole-like invertebrates, build elaborate mucus houses and pump water through filters to collect plankton and bacteria for food. When the house gets mucked up, the larvacean discards it and builds another.

Underwater Photos Credit: OOI-NSF/UW/CSSF

One Small Quake for Axial, One Giant Leap for the Ocean Observatory

Saturday, July 27th, 2013

ROPOS control room where the ROV is piloted and controlled

Here’s the current dive plan:  Go to the sea floor, deploy and connect instruments, collect some data, return to ship. Sounds straightforward, but this is a scheduled 32-hour dive and the devil is in the details and the unexpected events. Routine as it can sometimes seem to me watching the unflappable ROPOS operators, meticulous engineers and calm scientists in the ROPOS control room, the team is dealing with continually changing conditions, equipment issues, opportunities, and problems.

For one thing, the weather picked up yesterday and the ship started rocking and rolling, so they cut the last dive short and put off an instrument survey for the next dive. The team wanted to get ROPOS up quickly so they could turn around and dive again with a basket full of instruments that will help complete the subnet at Axial seamount.

ROPOS launches are tricky with ocean swells

With waves increasing to about 2 meters (6 feet) the launch crane operator waited for a swell to pass and eased ROPOS into the water and on its way down before the next surge pulled down on the wire holding the ROV. Ninety minutes later, ROPOS was on the bottom, setting down the instrument basket and getting to work. Even removing instruments from the basket is a well-choreographed series of events, I’ve heard it described here as a ballet. It’s a ballet with four principal dancers: an ROV driver, two men each operating a robotic arm, and the vehicle itself. This team is so skilled and their moves so well-rehearsed, they often don’t even speak to each other as one robotic arm clamps on the basket, the other lifts out an instrument and ROPOS floats up and across the sea floor to find the precise location to deploy the seismometer. Setting the instrument platform down on a flat patch of lava, a robotic arm turns four screws in succession to level the instrument (the difference between this piece of construction equipment and the bubble level familiar to carpenters is the deep sea levelers use a marble rather than a bubble to find the center point). Only when it’s settled and level will ROPOS connect the instrument to the cable, awaiting the flow of electrons from the ship to awaken the instruments.

On this dive, the team deployed two seismometers and one “tiltometer,” more properly known as the bottom pressure tilt meter. This instrumentROPOS connected cable to the Axial subnetwas developed by Bill Chadwick at NOAA’s Pacific Marine Environmental Laboratory to record the expansion and contraction of the volcano from the flow of magma below. Bill was a scientist-in-residence at the Exploratorium last year and he’s been studying the Axial volcano for two decades. He was on the ship in spirit and on the phone last night as the ROPOS team eased his instrument in place. It’s painstaking work and you can sometimes see the scientists and engineers squirm in their seats, wanting to reach out and help ROPOS complete this delicate task. But their instruments are in good hands, these Canadians know their ROV and they finished the task ahead of schedule.

Then it was time for the engineers to flip a switch (actually click on a computer screen) and activate the cable network that powers the instruments and carries data back through ROPOS to the ship. The plan was to collect data for six hours to make sure the instruments were working and the subnet infrastructure was ready to be plugged into the primary network that connects to the shore station and the Internet when the observatory goes live next year.

First in-situ earthquake recorded in real-time at Axial Volcano.

Once all the equipment was turned on and systems verified, the team in the ROPOS control room settled in to wait for data. For those awake at 4:30 AM, they didn’t have to wait long. Within 15 minutes, there was a tremor on Axial, picked up by one seismometer, then the other in quick succession. It was a nice moment for the night owls working on the R/V Thompson and for those of us who woke up to a beautiful data graph the next morning.

As the Spool Turns

Wednesday, July 24th, 2013

9 PM Aboard the Thomas G. Thompson

ROV ROPOS with cable spool attached Today, it was all about the cables that deliver power and data to the ocean observatory’s secondary nodes at the Axial volcano. As anyone with an old house knows, wiring can be a troublesome thing and you definitely don’t want to take any chances with it. Earlier this morning, the ROV ROPOS attached a large spool of bright orange cable to its belly and set out to descend almost a mile to the sea floor to connect to the equipment waiting on the bottom and lay the cable. As I watched from the back of the ROPOS control room, the shift supervisor asked to zoom the camera in on the cable loops for a closer look. He didn’t like what he saw. The normally plump, round “oily” cable was flattened, indicating that it might be leaking oil and exposing the wiring inside to the corrosive seawater outside. Rather than take a chance that it would fail in the future, the team of scientists and engineers onboard decided to bring the spool back up for a closer look and some testing of the cable.

A major activity of Visions 13 expedition this summer is to lay extension cables for the Regional Scale Network of the Ocean Observatories Initiative. In total, this network of instruments, cameras, and interactive experiments will be connected to shore by 900 km (560 miles) of backbone cable. This is no ordinary cable: it can carry up to 200 kilowatts of power and up to 240 gigabits of data a second. It’s rugged as well, built to endure a long trip to the seafloor where it’s exposed to corrosive seawater and pressures up to 4000 pounds per square inch. This is the true infrastructure that will make interactive, 24/7 oceanography possible. To be sure, the instruments that plug into it are state-of-the art. But as chief scientist John Delaney says, the young scientists of today will dream up new instruments and experiments in the future and that infrastructure will be there for the 30-year lifetime of the cabled observatory.

Laying cable on the ocean floor has a long and storied history, beginning in 1850 with a telegraph cable between England and France. The first audacious attempt to wire Europe and North America with a trans-Atlantic communications cable was dreamt up by Massachusetts paper magnate Cyrus W. Field. In 1857, 2,500 miles of cable was coiled into drums and loaded aboard two sailing vessels each loaded with 1500 tons weight. The heavy cable kept breaking on route, even as engineers tried repairing it as was being spooled across the ship deck. But after much frustration, they finally succeeded in joining the two continents and the first telegraph was sent from Queen Victoria to President James Buchanan on August 16, 1858.  Alas, the cable began degrading and the connection only lasted for two weeks. It took another eight years before the next, more successful cable was laid and it persisted.

Co-chief scientist Giora Proskurowski checks the oil recovered from cable.

For today, the cable coiled on the Thompson’s deck will no doubt fair much better than Cyrus Field’s first submarine telegraph cable. The return trip to the surface proved that the oily cable didn’t contain as much oil as it should so the engineers drained it and will perform pressure testing later to make sure there are no leaks. If it holds, they plan to refill it with a special silicon oil, seal the cable ends and return it again to the sea floor to connect it to a seismometer that will rest on the Axial seamount until the next volcano. Cyrus Field would be proud.

Waiting for the (not terribly) Big One

Monday, July 22nd, 2013

Aboard the R/V Thomas G. Thompson, 2 PM

Axial Seamount node, courtesy of Univ. of Washington

We’re spending a few days at the Axial Caldera, laying cable that will eventually connect instruments, sensors and HD cameras to the entire regional network to study and interact with this underwater volcano in real time. Axial Seamount is a great study site because it’s an active volcano (albeit not nearly as explosive as Mount St. Helens was in 1980) . From recent events scientists think it erupts about every 10-12 years. In fact, right now ROPOS is laying cable directly over fresh lava from an eruption in 2011.

The regional cabled observatory  component of the National Science Foundation’s Ocean Observatories Initiative will instrument and wire the volcano so that the next eruption can be studied in real time from beginning to end. Chief scientist, John Delaney, says this is valuable both to investigate the underlying mechanisms and geology of submarine vulcanism, whose eruptions can trigger tsunamis, but also measure the gases, heat and fluids that flow from beneath the sea floor and contribute to living communities in the deep sea (more on the chemistry and biology of these systems in later posts).

Axial Seamount is part of a chain of underwater volcanoes that dot the length of the spreading zone where the Juan de Fuca tectonic plate pulls away from the Pacific plate. The earth’s crust is thinner along these undersea volcanic ridges, which means it doesn’t take as much pressure for the magma below to erupt through the surface and start flowing. [The Hawaiian Islands are also a chain of volcanoes so productive that they’ve now become aerial volcanoes. The Big Island of Hawaii is the youngest in the chain and growing all the time from the eruptions of the Kilauea volcano. The next in line, Loihi Seamount, is about 1000 meters below the surface just off the Big Island.]

More than 60% of the planet’s vulcanism happens underwater but that has been difficult to study up to now because, well, itEruptive blast, courtesy of NSF and NOAA happens underwater.  In 2009, during an expedition sponsored by NOAA and NSF, scientists filmed an active eruption during an ROV dive in the Lau Basin in the Eastern Pacific, complete with sound, but they couldn’t stay long. When completed, the cabled observatory will have eyes, ears and sensors on the Axial Volcano to capture its every burp and lava flow with instruments that include a tripod-mounted bottom tilt and pressure instrument that will measure the inflation and deflation of the seafloor (an indication of magma rising up), a titanium-encased broadband seismometer and low-frequency hydrophone to detect earthquakes in real time, and HD video and still cameras to capture the live action of events on the sea floor. These instruments will help scientists better understand when and how volcanoes erupt and the ways they contribute to the biology, chemistry and overall geology of the ocean.