1. Temporal Dynamics of Dissolved Oxygen in Massachusetts Bay Amanda Hyde Advisors: Doug Vandemark & Joe Salisbury Research and Discovery, 2009 Amanda Hyde Advisors: Doug Vandemark & Joe Salisbury Research and Discovery, 2009

2. Initial Question: Has the DO in GOM experienced an average decrease over the past century due to the temperature rise? The Motivation: o Shearman et al., 2004 showed eastern seaboard experiencing 0.02°C yearly temperature rise. o SST data from Boothbay Harbor agrees. o Had access to long term data in GOM. (Shearman, R. K., Lentz, S. J., Silverthorne, K., 2004. Sea surface temperature variability along the Middle Atlantic bight over the last 100 years. EOS Trans. AGU, 84: 52, Ocean Sci. Meeting Suppl., Abstract OS21N-03)

3. Measurements and Constraints Tools of Measurement oWinkler oSeabird oOptode Tools of Measurement oWinkler oSeabird oOptode DO Depends On… o1st Order Physics like Temperature & Salinity oBiology (photosynthesis/ respiration) oCirculation Physics (storms/river discharge/water masses) (Hyde, 2009)

4. [O 2 ] Equations: AOU = [O 2 ] equ -[O 2 ] Percent Saturation of [O 2 ] = ([O 2 ]/[O 2 ] equ )*100 o Equilibrium Oxygen determined by Table 1 of Garcia and Gordon based on temperature and salinity values. (Benson and Krause, 1984) (Benson, B. B., Krause, Jr., D. 1984. The concentration and isotopic fractionation of oxygen dissolved in freshwater and seawater in equilibrium with the atmosphere. Limnology and Oceanography. 29,3: 620-632)

5. Seasonal Variability of DO

6. Water Masses in GOM o4 main water masses in the GOM oWater masses based on temperature, salinity, and depth ochange in slope on the T-S diagram indicates the change in water mass oFigure taken from Warn- Varnas, et al., 2005 oProfile is of June 1982 (Warn-Varnas, A., Gangopadhyay, A., Hawkins, J. A., Robinson, A. R., 2005. Wilkinson Basin area water masses: a revisit with EOFs. Continental Shelf Research. 25: 277-296.) o4 main water masses in the GOM oWater masses based on temperature, salinity, and depth ochange in slope on the T-S diagram indicates the change in water mass oFigure taken from Warn- Varnas, et al., 2005 oProfile is of June 1982 (Warn-Varnas, A., Gangopadhyay, A., Hawkins, J. A., Robinson, A. R., 2005. Wilkinson Basin area water masses: a revisit with EOFs. Continental Shelf Research. 25: 277-296.) T S

7. The Data oNODC oGOMOOS Buoy A oMouth of Merrimack River oBoothbay Harbor, ME SST oNODC oGOMOOS Buoy A oMouth of Merrimack River oBoothbay Harbor, ME SST

8. What Happened? oMany factors influence DO value, not just temperature and salinity oGOM is a complex system oNot enough resolution in the NODC data oMany factors influence DO value, not just temperature and salinity oGOM is a complex system oNot enough resolution in the NODC data

9. GOMOOS Buoy A Data Temperature’s Effect on DO:

10. Effects of River Discharge & Storms on DO

11. Yearly Difference in Percent Saturation Test=Wilcoxon/Mann- Whitney U-test, p<0.0001, DF=6 Tukey’s HSD test, p<0.05 Test=Wilcoxon/Mann- Whitney U-test, p<0.0001, DF=6 Tukey’s HSD test, p<0.05 ABBDCCC AADBCBC BCC

12. In Conclusion… oCould not conclude that the DO in Massachusetts Bay is decreasing as temperature increases: too many contributing parameters. oBetter resolution, long-term data necessary to answer initial question. oTemperature does significantly affect DO value. oStorms play a significant role on DO in the GOM. oThere is a significant different in percent saturation values from year to year. oCould not conclude that the DO in Massachusetts Bay is decreasing as temperature increases: too many contributing parameters. oBetter resolution, long-term data necessary to answer initial question. oTemperature does significantly affect DO value. oStorms play a significant role on DO in the GOM. oThere is a significant different in percent saturation values from year to year.

13. What’s Next? oCollect more high resolution data over longer time span; thus enabling better sense of correlations. oSources like GOMOOS and MWRA provide highly valuable data sets. oCollaboration with USECoS. oCan DO changes be tracked from satellites? oCould biological and circulation physical controls help offset the decrease in DO due to global warming? oCollect more high resolution data over longer time span; thus enabling better sense of correlations. oSources like GOMOOS and MWRA provide highly valuable data sets. oCollaboration with USECoS. oCan DO changes be tracked from satellites? oCould biological and circulation physical controls help offset the decrease in DO due to global warming? (Hyde, 2009)

14. Special Thanks to… oMy advisors Doug Vandemark and Joe Salisbury oChris Hunt and Mimi Szeto for aiding me in programming MATLAB oMark Lazzari of the Department of Marine Resources, State of Maine oNational Oceanographic Data Center oGulf of Maine Ocean Observation System oU.S. Geological Survey for Merrimack River discharge data oMy advisors Doug Vandemark and Joe Salisbury oChris Hunt and Mimi Szeto for aiding me in programming MATLAB oMark Lazzari of the Department of Marine Resources, State of Maine oNational Oceanographic Data Center oGulf of Maine Ocean Observation System oU.S. Geological Survey for Merrimack River discharge data

15. References oApplebaun, S., Montagna, P. A., Ritter, C. 2005. Status and trends of dissolved oxygen in Corpus Christi Bay, Texas, U.S.A. Environmental Monitoring and Assessment 107: 297-311. oBoyer, T., Conkright, M. E., Levitus, S. 1999. Seasonal variability of dissolved oxygen, percent oxygen saturation, and apparent oxygen utilization in the Atlantic and Pacific Oceans. Deep-Sea Research I. 46: 1593-1613. oCraig, H., Hayward, T. 1987. Oxygen supersaturation in the ocean: bioloigical versus physical contributions. Science, New Series. 235, 4785: 199-202. oGarcia, H. E., Boyer, T. P., Levitus, S., Locarnini, R. A., Antonov, J., 2005. On the variability of dissolved oxygen and apparebt oxygen utilization content for the upper world ocean: 1955 to 1998. Geophysical Research Letters. 32. oHopkins, T. S., Garfield III, N., 1979. Gulf of Maine intermediate water. Journal of Marine Research 37: 103-139. oLibes, S. M., 1992. An introduction to marine biogeochemistry. John Wiley & Sons, Inc. New York. oLoder, J. W., Shore, J. A., Hannah, C. G., Petrie, B. D. 2001. Decadal-scale hydrographic and circulation variability in the Scotia-Maine region. Deep-Sea Research II. 48: 3-35. oNajjar, R., Siewert, J., O’Reilly, J. Respiration in the Gulf of Maine inferred from climatologies of dissolved oxygen and primary production. (poster) oPilson, M. E. Q., 1998, An introduction to the chemistry of the sea. Prentice Hall. Upper Saddle River, New Jersey. oTomczak, M. 1999. Some historical, theoretical and applied aspects of quantitative water mass analysis. Journal of Marine Research. 57: 275-303. oWanamaker Jr., A. D., Kreutz, K. J., Sche, B. R., Maasch, K. A., Pershing, A. J., Borna, H. W., Introne, D. S., Feindel, S. 2009. A late Holocene paleo-productivity record In the western Gulf of Maine, USA, inferred from growth histories of the long-lived ocean quahog (Arctica islandica). Int J Earth Sci. 98: 19-29. oWarn-Varnas, A., Gangopadhyay, A., Hawkins, J. A., Robinson, A. R., 2005. Wilkinson Basin area water masses: a revisit with EOFs. Continental Shelf Research. 25: 277-296. oApplebaun, S., Montagna, P. A., Ritter, C. 2005. Status and trends of dissolved oxygen in Corpus Christi Bay, Texas, U.S.A. Environmental Monitoring and Assessment 107: 297-311. oBoyer, T., Conkright, M. E., Levitus, S. 1999. Seasonal variability of dissolved oxygen, percent oxygen saturation, and apparent oxygen utilization in the Atlantic and Pacific Oceans. Deep-Sea Research I. 46: 1593-1613. oCraig, H., Hayward, T. 1987. Oxygen supersaturation in the ocean: bioloigical versus physical contributions. Science, New Series. 235, 4785: 199-202. oGarcia, H. E., Boyer, T. P., Levitus, S., Locarnini, R. A., Antonov, J., 2005. On the variability of dissolved oxygen and apparebt oxygen utilization content for the upper world ocean: 1955 to 1998. Geophysical Research Letters. 32. oHopkins, T. S., Garfield III, N., 1979. Gulf of Maine intermediate water. Journal of Marine Research 37: 103-139. oLibes, S. M., 1992. An introduction to marine biogeochemistry. John Wiley & Sons, Inc. New York. oLoder, J. W., Shore, J. A., Hannah, C. G., Petrie, B. D. 2001. Decadal-scale hydrographic and circulation variability in the Scotia-Maine region. Deep-Sea Research II. 48: 3-35. oNajjar, R., Siewert, J., O’Reilly, J. Respiration in the Gulf of Maine inferred from climatologies of dissolved oxygen and primary production. (poster) oPilson, M. E. Q., 1998, An introduction to the chemistry of the sea. Prentice Hall. Upper Saddle River, New Jersey. oTomczak, M. 1999. Some historical, theoretical and applied aspects of quantitative water mass analysis. Journal of Marine Research. 57: 275-303. oWanamaker Jr., A. D., Kreutz, K. J., Sche, B. R., Maasch, K. A., Pershing, A. J., Borna, H. W., Introne, D. S., Feindel, S. 2009. A late Holocene paleo-productivity record In the western Gulf of Maine, USA, inferred from growth histories of the long-lived ocean quahog (Arctica islandica). Int J Earth Sci. 98: 19-29. oWarn-Varnas, A., Gangopadhyay, A., Hawkins, J. A., Robinson, A. R., 2005. Wilkinson Basin area water masses: a revisit with EOFs. Continental Shelf Research. 25: 277-296.