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St. Petersburg Coastal and Marine Science Center

St. Petersburg Coastal and Marine Science Center > Ocean Acidification

Ocean Acidification

Arctic Cruise 2012: Questions & Answers

Have a question for the scientists? Please submit your question in the box at right. Due to the volume of questions we receive, we will not be able to answer every one. However, we will do our best to answer as many as possible. Also, before you ask a question, scroll down through the answered questions to be sure an answer has not already been posted for your question.

Q: For how many years have you been doing this?

A: We have been studying Ocean Acidification in the Arctic Ocean since the summer of 2010.

Q: Are the carbonate mineral saturation states also affected by temperature?

A: Yes, carbonate mineral saturation states are affected by temperature.  In general, carbonate mineral saturation states decrease with decreasing temperature.  For example, a drop in temperature from 25 to 0 degrees C at constant dissolved inorganic carbon (DIC) concentration of 2000 micromoles kg-1 and total alkalinity of 2440 micromoles kg-1 at a salinity of 35 would cause a decrease in carbonate mineral saturation state of approximately 0.5. Zeebe and Wolf-Gladrow (2001) provide an excellent discussion of the effects of temperature, salinity, and pressure on the carbonate system parameters in seawater.

Zeebe, R.E. And Wolf-Gladrow D.  2001.  CO2 in Seawater: Equilibrium, Kinetics, Isotopes.  Boston: Elsevier, 346pp.

Q:  How do you measure the impact of Ocean Acidification on your location?

A: One of the effects of ocean acidification is a decrease in carbonate mineral saturation states.  We are measuring carbonate chemistry in seawater at a very high spatial resolution and very accurately so we can calculate the variation in carbonate mineral saturation states across the arctic ocean.  These data provide a baseline to compare to past and future measurements of seawater carbonate mineral saturation states so we can quantify the effects of increasing atmospheric co2 and ocean acidification on this parameter.

Q: Is the Northwest Passage open this year?

A: The National Snow and Ice Data Center is now reporting that it looks as if the Arctic ice extent is below 2007 levels.  Due to this elevated ice sheet melt in the Arctic this year, there are several small vessels attempting to make the journey through the Northwest Passage.  The passage is by no means totally free of ice as of yet to accommodate large vessels, however it may be possible in the future if the sea ice continues to melt more each year.

Q: What is the best solution for Ocean Acidification?

A: Right now, there is no solution to Ocean Acidification.  The current research may give scientists much needed information about this very real issue so that a long term solution can be found.  A good start would be to lower global carbon dioxide emissions.

Q: What kinds of samples are you collecting  (air, water, plants, animals) and what are you looking for in the samples that you collect?

A: We are collecting seawater samples and measuring carbonate system parameters including temp, sal, total alkalinity, dissolved inorganic carbon, pco2, and ph.  We are also measuring carbon and oxygen isotopes.  These data allow us to very accurately determine the concentrations of co2 and ph of the water and the flux of co2 from air to water or vice versa in areas that are covered with sea ice and where sea ice has melted away.  These data also allow us to calculate carbonate mineral saturation states that are an important indicator of the effects of ocean acidification on marine organisms that produce their skeletons from calcium carbonate minerals.

Q: How far will the cruise go this year?

A: The 2012 cruise begins northwest of Barrow, Alaska and extends to the North and then back to the South.  This track is west of the 2011 cruise track and is based on the research of the Extended Continental Shelf Project team.

Map of proposed 2012 cruise track.


Q: How did you decide on the proposed path for the ship to travel during the 2012 cruise?

A: The proposed path for the Healy was determined by the Chief and Co-Chief Scientist, Larry Mayer and Andy Armstrong for this voyage in consultation with the other Extended Continental Shelf Project team members.

Q: When does the 2012 cruise begin?

A: August 25, 2012.


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