The day started out much the same way as the day before ended, with us steaming. But within a few hours, we were beginning to see newly forming pancake ice! There is nothing on this earth that is as beautiful as sea ice and if I needed reaffirmation of that, I got it today as we steamed through endless pancake ice to our next station inside M’Clure Strait. As we approached Banks Island and the promontory that marked the opening to the Strait, the ice became a bit thicker and there was a quiet excitement to be sampling in this new and exciting area so far north.
Ice with Cape M’Clure in the distance
We continued around Cape M’Clure and into the Strait where we were going to sample, getting only 700 meters from shore for our first sampling station. The sun was shining and it has to be one of the most beautiful places I have ever been. With pancake ice forming before our eyes and yellow glowing cliffs, we watched the sun set over the cliff as we positioned the boat. Truly a magical spot and to think about how few people have been here and the explorers that came here so long ago blew my mind. Then it got dark and the moon was out and shining brightly, reflecting on the ice. Only one word can describe this place: stunning. Hard to put into words, but very special…as one person said, we are in a remote and special place…I couldn’t say it better…
Looking into the Strait: Cape Crozier
Out of the Strait: Cape M’Clure
Larger Pancake Ice as we headed to our sampling station
At our sampling station, only 700m from shore
The sun setting behind Banks Island
A beautiful Arctic night
After 36 hours of steaming, the day dawned with a beautiful sunrise over Robilliard Island as we arrived at our sampling station just south of M’Clure Strait in the Canadian Archipelago. The wind has certainly picked up and the seas are rough and choppy. It is much colder up here as the entire deck is encrusted in ice and slush. With the soft light of the day, it is quite beautiful. The days are getting shorter and shorter both as we head north and get later in the year. I believe we are losing about nineteen minutes of sunlight each day!
We have been collecting water samples along our transect the entire day in order to determine our next sampling area. Hopefully it will involve getting into some ice as the area around the ice edge is particularly interesting in terms of productivity and ocean chemistry!
The ship’s wake as we head east…
After finishing up the first phase of the cruise yesterday, we began to steam east late last night. We are about midway through our 36-hour steam to the Canadian Archipelago where we will be sampling in the ice and along the ice edge. Heading so far to the north and east means we will be “off the edge” of our internet service for a few days so stay tuned after the weekend for updates! Hopefully there will be lots to report from our time in the ice…
The purpose of this cruise is to learn about the ocean chemistry of the Arctic Ocean and in particular ocean acidification. So the question is, what is ocean acidification (OA) and why do we care? The short answer is that OA is the decrease in pH of the ocean due to increased free hydrogen ions in the water making it more acidic. We care because with this increasing acidity, the amount of carbonate minerals, in particular calcite and aragonite, available for animals to use for shell production and other metabolic needs, decreases and the ocean becomes under-saturated with respect to these carbonate ions.
Here is a diagram of the chemical reaction that leads to ocean acidification with the introduction of carbon dioxide, CO2, into the ocean. In the past century, since the Industrial Revolution, more and more CO2 is introduced from anthropogenic sources. The carbon dioxide enters the ocean, a sink for the CO2, where it combines with water and becomes carbonic acid which is very unstable. The carbonic acid breaks apart leaving a free hydrogen atom and bicarbonate. The resulting bicarbonate breaks up farther becoming a carbonate ion and another free hydrogen ion. Acidity is dependent on the number of hydrogen atoms in the water column so with more hydrogen atoms, you get a lower pH or higher acidity. On this cruise, dissolved inorganic carbon (DIC) and alkalinity are measured in order to derive pH. Alkalinity is the measure of the buffering capacity of water or the capacity of the water to neutralize acids. This buffering capacity is largely in the form of bicarbonate.
This graph shows the increase in CO2 concentration in the atmosphere since the 1950s and is the longest time series of data for this measurement. The ocean is a sink for much of this CO2 and has taken up between 1/3 and ½ of all anthropogenic CO2 emissions. Because the amount of CO2 in the ocean’s surface waters has increased considerably, the acidity of the ocean has increased due to the reaction outlined above. This increased acidity is highlighted in the Arctic regions where the ocean is naturally low in carbonate ion concentration due to ocean mixing patterns and increased solubility of CO2 in cold water.
The water samples collected on this cruise will help to build a better, more accurate, picture of how the increasing CO2 in our atmosphere will impact these fragile ecosystems.
The new mooring buoy ready to be deployed
After recovering two moorings yesterday, the team did a quick turnaround due to impending weather and redeployed them today. Like recovering the mooring, deploying was quite an operation done with careful precision. The BS3 mooring with all of its various instruments was redeployed to collect data for another year adding to the time series of data from this location.
Fresh new instruments being deployed. An ADCP and pCO2 Sensor
The Mooring Anchor
Right before heading into the depths…
See you in a year…
With the mooring operations complete, we are moving on to Phase II of the expedition which involves a long steam northeast to the Canadian Archipelago where we will be completing CTDs and water sampling along the shelf. I am very exciting for this work as we will be heading into the ice!
The BS3 Mooring coming down the Port side of the ship after being released from its anchor
After continuing our sampling through the night, it was time to recover the BS3 mooring in the waters northeast of Barrow. The recovery of the mooring is quite an impressive process. This mooring was deployed on last year’s cruise and has been taking measurements of the water column for the past year creating an incredible data set that is key to understanding the Arctic shelf ecosystem. The instruments on the mooring have been collecting various measurements including temperature, salinity, nitrate, pCO2, and pH.
Everyone is anxious to get back to the lab to look at the data collected from these instruments and create a picture of what the water column looked like for the past year, from the open water of the fall through the ice-covered winter through the spring and summer melt until now. The changing ocean conditions affect the measurements tremendously as do currents and upwellings that occur seasonally in this area. By understanding these variables, the scientists can better understand what will happen when there is less ice in the future due to the warming climate.
Preparing the snowy deck for the recovery of the mooring
The small boat hooks a line from the boat onto the buoy
The first part of the mooring coming on board. The pCO2 censor is on the chain behind.
Successful recovery of the mooring!
Dr. Jeremy Mathis with his pCO2 censor from the mooring…excited to see the data!
The mooring will be re-deployed in the coming days to collect data for the next year.
The key to getting research accomplished both in the field and in the lab is a good team. Dr. Jeremy Mathis has put together a stellar group of young scientists in his Ocean Acidification Research Center (OARC) at University of Alaska-Fairbanks. I am having the pleasure of working with and learning from two of his current students while on board, Jessica Cross, a PhD student, and Stacy Reisdorph, a Masters student. Jessica and I sat down for a little chemistry lesson last night before she went on watch and I learned all about her research and her path to studying ocean chemistry…
Jessica takes a water sample after a deep cast
The USCGC Healy has become like a second home to Jessica as she has spent, in the past two years, more than 200 days aboard sailing mostly in the Bering Sea in order to collect data for her PhD research. A few years ago, when Jessica was a freshman at Rhodes College in Tennessee, she would never have imagined herself studying chemistry, let alone oceanography, as her first passions were books and writing. Now entering her fourth year of her PhD, she can’t imagine doing anything else and shows giddy excitement for ocean chemistry and endless enthusiasm for her work. Spending all of those days at sea after her initial coursework gave her a thorough understanding of basic oceanographic concepts and she explains how there is no better way to learn than to be at sea with other scientists who are willing to share their knowledge and experience. In the short time I have been at sea with Jessica, it is clear that she knows how to get work done efficiently and enjoys collecting samples for not just her own research but for the lab as a whole.
Jessica’s work focuses on ocean acidification in the Bering Sea as part of the Bering Ecosystem Study project (BEST). (Note: GOE participated in a BEST cruise in April/May 2008 in the Bering Sea…see Bering Sea Ice Expedition for more details) Jessica has been collecting and analyzing water samples from the Bering Sea for Dissolved Organic Carbon (DIC) and Alkalinity in order to determine the pH (measurement of acidity) of the water. Armed with this knowledge, she then can figure out the carbonate saturation state that is vital to the shell-building animals of the ocean, and in the Bering Sea in particular, the King Crab. The Bering Sea is a particularly interesting system, as is the Arctic Ocean, because of the variety of water mixing from river outflows, deepwater upwelling, surface water and ice melt creating an acidic environment in its natural state of equilibrium due to these various natural inflows of carbon dioxide. The question for the present and the future, is whether the increased anthropogenic carbon dioxide, and in turn the decreased pH in the Bering Sea, will affect the animals’ ability to adapt to their changing environment? Jessica seeks to quantify these changes and her excitement for the work is contagious.
Recovering a mooring recording the sounds of the Arctic
We are in the middle of the first phase of the cruise which consists of recovering and deploying moorings in the Chukchi and Beaufort Seas. Most of these moorings have been on the bottom of the ocean collecting data since being deployed on last year’s cruises. It is amazing to think about the time series of data that these instruments are collecting. There are a variety of moorings being deployed and recovered, collecting all kinds of data, from physical oceanography data, to chlorophyll measurements to acoustic data listening for passing mammals. So much can be learned from these instruments because they are in situ for so long monitoring the changes throughout the year.
Mooring operations must be completed in daylight so we have been doing CTD casts all night and the mooring ops and any necessary transiting during the day. Ship time is valuable so all minutes and hours of the day must be used efficiently. We have a few more days of mooring ops to complete before moving on to the second phase of the cruise which will consist of 24 hour a day CTD casts and water sampling!
Shortly after midnight, with the lights of Barrow glowing in the distance, we arrived at our next sampling line, the DBO line.
Deploying the CTD rosette with Barrow glowing in the distance
The DBO or Distributed Biological Observatory is an Arctic biological time series designed by Dr. Jackie Grebmeier from the University of Maryland (http://arctic.cbl.umces.edu/) to look at core oceanographic parameters such as temperature and nutrients in regional hotspots in the Arctic throughout the year. This line consists of eight stations in the waters just offshore of Barrow crossing Barrow Canyon. This time series is based on the cooperation of various research ships from the USA, Canada, Russia, China and Japan, committing to sample this line when they are operating in the Chukchi Sea. I wanted to make sure to highlight the DBO in the blog because of the magnitude of importance of this kind of multi-national cooperation amongst scientists. This collaboration and cooperation allows the collection of a tremendous data set that creates an annual and seasonal time series that will be able to quantify the changes to this important Arctic Ocean ecosystem in the face of climate change.
Map of DBO Lines (from http://pag.arcticportal.org)
Slate-Colored Junco (Photo credit: Luke DeCicco/USFWS)
In the wee hours of the morning, we began the CTD casts along our first transect and continued to sample throughout the night until the late morning when it was time to retrieve a mooring. The mooring had been deployed last year in order to record salinity, temperature and a variety of other physical parameters of the water. The scientists are excited to retrieve their instruments and find out what has happened in the year since its deployment.
It is kind of a cloudy and cold day with snow dusting the decks but we still are experiencing calm seas. There have been quite a few birds surrounding the ship including a songbird, a Slate-Colored Junco, a subspecies of the Dark-Eyed Junco, that must have lost its way from its home in the arboreal forest. One of my favorite things about being at sea is discovering these little creatures seeking refuge on the ship after they have lost their way. This little guy hung out on the boat for a while before hopefully heading south out of the Arctic. They are not often spotted this far north so he had certainly lost his way.