Yutaka W. Watanabe (Ph.D.)

 

Associate Professor

 

 

 

 

Address:

Faculty of Environmental Earth Science,

Hokkaido University

N10, W5, Kita-ku, Sapporo, Hokkaido 060-0810, Japan

Tel: +81(11)-706-2371

E-mail: yywata at ees.houdai.ac.jp

 

Research keywords:

Ocean biogeochemistry, Chemical oceanography, Carbon cycle, Nitrogen cycle, Gas exchange at the air-sea, Global warming, Climate change, Ocean acidification, Radioisotope, Southern Ocean, Pacific Ocean

 

Research intersets:

My scientific interests emcopass the  ocean biogeochemical dynamics including carbon cycle and nitrogen cycle. My recent subjects focus on the changes in carbon and nitrogen cycles due to the global warming, and these feedback effects on our planet. 

 

Academic scientific papers:

  • Shigemitsu, M., Yamanaka, Y., Watanabe, Y. W., Okada, N., Kriestb, I., Oschliesb, A., Watanabe, Y. W., Shigemitsu, M., Ujiie, T., Minami, H. (2014): Decadal shift of biogenic sinking particle flux in the western North Pacific subpolar region. Geophysical Research Letters, doi: 10.1002/2013GL059142.
  • Watanabe, Y. W. (2013): Investigation of changes in ocean carbon and nitrogen cycles based on analytical chemical approach (in Japanese with English abstract). Bunseki,  62, 1049-1056.
  • Nishioka, J., Nakatsuka, T., Watanabe, Y. W., Kuma, K., Ogawa, H. Ebuchi, N., Scherbinin, A., Volkov, Y. N., Shiraiwa, T., Wakatsuchi, M. (2013): Intensive mixing along an island chain controls oceanic biogeochemical cycles. Global Biogeochemical Cycles, 27, 1-10, doi:10.1002/gbc.20088.
  •  Shigemitsu, M., Nishioka, J., Watanabe, Y. W., Yamanaka, Y., Nakatsuka, T, Volkov, Y. N. (2013): Fe/Al ratios of suspended particulate matter from intermediate water in the Sea of Okhotsk: Implications for long-distance lateral transport of particulate Fe. Marine Chemistry, 157, 41-48, doi: org/10.1016/j.marchem.2013.07.003.
  • Tanaka, S. S., Watanabe, Y. W., Ono, T., Aramaki, T. (2013): Spatial high-resolution estimation of net oxygen production during spring bloom in the western North Pacific using dissolved oxygen, nitrogen and argon. Marine Chemistry, 149, 85-95, doi:10.1016/j.marchem.2013.01.001.  
  • Watanabe, Y. W., Nishioka, J., Nakatsuka, T. (2013): Decadal time evolution of oceanic uptake of anthropogenic carbon in the Sea of Okhotsk. Geophysical Research Letters, 40, 1-5, doi:10.1002/grl.50113.
  • Shigemitsu, M., Watanabe, Y. W., Yamanaka,Y., Honda, M. C., Kawakami, H. (2011): Relationship between sinking organic matter and minerals in the shallow zone of the western subarctic Pacific. Journal of Oceanography, 66(5), 697-708, doi:10.1007/s10872-010-0057-1. 
  • Watanabe, Y. W., Chiba, T, Tanaka, T. (2011): Recent change in the oceanic uptake rate of anthropogenic carbon in the North Pacific subpolar region determined by using a C-13 time series. Journal of Geophysical Research, 116, C02006, doi:10.1029/2010JC006199.
  • Oguma, S., Ono, T., Watanabe, Y. W., Kasai, H., Watanabe, S., Nomura, D., Mitsudera, H. (2011): Flux of low salinity water from Aniva Bay (Sakhalin Island) in the southern Okhotsk Sea. Estuarine Coastal and Shelf Science, 91, 24-32, doi:10.1016/j.ecss.2010.10.002.
  • Yoshimura, T., Nishioka, J. Suzuki, K., Hattori, H., Kiyosawa, H., Watanabe, Y. W.(2010): Impacts of elevated CO2 on phytoplankton community composition and organic carbon dynamics in nutrient-depleated Okhotsk Sea surface water. Journal of Experimental Marine Biology and Ecology, 395, 191-198, doi:10.1016/j.jembe.2010.09.001.
  • Shigemitsu, M., Yamanaka, Y., Watanabe, Y. W., Maeda, N., Noriki, S. (2010): Seasonal characteristics of the nitrogen isotope biogeochemistry of settling particles in the western subarctic Pacific: a model study. Earth and Planetary Science Letters, 293, 180-190, doi:10.1016/j.epsl.2010.01.043.
  • Tsumune, D., Nishioka, J., Shimamoto, A., Watanabe, Y. W., Aramaki, T., Nojiri, Y., Takeda, S., Tsubono, T. (2009): Physical behaviours of iron fertilized patch in SEEDS II. Deep-Sea Research II, 56, 2948-2957, doi:10.1016/j.dsr2.2009.07.004.
  • Watanabe, Y. W., Nishioka, J., Shigemitsu, M., Mimura, A., Nakatsuka, T. (2009): Influence of riverine alkalinity on carbon species in the Okhotsk Sea. Geophysical Research Letters, 36, L15606, doi:10.1029/2009GL038520.
  • Shigemitsu, M., Watanabe, Y. W., Narita, H. (2009): Sedimentary inorganic nitrogen and its isotope ratio in the western subarctic Pacific over the last 145 kyr. Journal of Oceanography, 65, 541-548.
  • Ikeda, M., Greve, R., Hara, T., Watanabe, Y. W., Ohmura, A., Kawamiya, M. (2009): Identifying crucial issues in climate science: drastic change in the earth system during global warming. EOS Transactions, 90(2), 15.
  • Ishida, H., Watanabe, Y. W., Ishizaka, J., Nakano, T., Nagai, N. (2009): Possibility of recent changes in vertical distribution and size-composition chlorophyll-a in the western North Pacific region. Journal of Oceanography, 65, 179-186.
  • Shigemitsu, M., Watanabe, Y. W., Narita, H. (2008): Time variations of δ 15N of organic nitrogen in deep western subarctic Pacific over the last 145 kyr. Geochemistry, Geophysics, Geosystems, 9(10), Q10012, doi:10.1029/2008GC001999.
  • Sakamoto, A., Watanabe, Y. W., Kido, K., Osawa, M., Noriki, S. (2008): Time series of multiple chemical parameters of CO2 in Otaru coast in Hokkaido, Japan: Evidence of the important role of coastal region for CO2 flux between air and Sea. Estuarine, Coastal and Shelf Science, 79, 377-386, doi:10.1016/j.ecss.2008.04.013.
  • Watanabe, Y. W., Shigemitsu, M., Tadokoro, K. (2008): Evidence of change in oceanic fixed nitrogen with decadal climate change in the North Pacific subpolar region. Geophysical Research Letters, 35, L01602, doi:10.1029/2007GL032188.
  • Tsuda, A., Takeda, S., Saito, H., Nishioka, J., Kudo, I., Nojiri, Y., Suzuki, K., Uematsu, M., Wells, M. L., Tsumune, D., Yoshimura, T., Aono, T., Aramaki, T., Cochlan, W. P., Hayakawa, M., Imai, K., Isada, T., Iwamoto, Y., Johnson, W. K., Kameyama, S., Kato, S., Kiyosawa, H., Kondo, Y., Levasscur, M., Machida, R., Nagao, I., Nakagawa, F., Nakanishi, T., Nakatuka, S., Narita, A., Noiri, Y., Obata, H., Ogawa, H., Oguma, K., Ono, T., Sakuragi, T., Sasakawa, M., Sato, M.,, Shimamoto, A., Takata, H., Trick, C. C., Watanabe, Y. W., Wong, C. S., Yoshie, N. (2008): Evidence for the grazing hypothesis: grazing reduces phytoplankton responses of the HNLC ecosystem to iron enrichment in the western Subarctic Pacific (SEED II). Journal of Oceanography, 63, 983-994.
  • Tanaka, S. S., Watanabe, Y. W. (2007): High accuracy method for determining nitrogen, argon and oxygen in seawater. Marine Chemistry, 106, 516-529, doi:10.1016/j.marchem.2007.05.005.
  • Shigemitsu, M., Narita, H., Watanabe, Y. W., Harada, N., Tsunogai, S. (2007): Ba, Si, U, Al, Sc, La, Th, C and 13C/12C in a sediment core in the western Subarctic Pacific as proxies of past biological production. Marine Chemistry, 106, 442-455, doi:10.1016/j.marchem.2007.04.004.
  • Watanabe, Y. W., Yoshinari, H., Sakamoto, A., Nakano, Y., Kasamatsu, N., Midorikawa, T., Ono, T. (2007): Reconstruction of dimethylsulfide in the North Pacific surface water during 1970s to 2000s. Marine Chemistry, 103, 347-358, doi:10.1016/j.marchem.2006.10.004.
  • Sakamoto, A., Niki, T., Watanabe, Y. W. (2006): Establishment of long-term preservation for dimethylsulfide (DMS) by solid-phase micro extraction (SPME) method. Analytical Chemistry, 78, 4593-4597.
  • Nakano, Y., Kimoto, H., Watanabe, S., Harada, K., Watanabe, Y. W. (2006): Simultaneous vertical measurements of in situ pH and CO2 in the sea using spectrophotometric profilers. Journal of Oceanography, 62, 71-82.
  • Ono, T., Kasai, H., Midorikawa, T., Takatani, Y., Saito, K., Ishii, M., Watanabe, Y. W., Sasaki, K. (2005): Seasonal and interannual variation of DIC in the Oyashio mixed layer: a climatological view. Journal of Oceanography, 61, 1059-1074.
  • Watanabe, Y. W., Ishida, H., Nakano, T., Nagai, N. (2005): Spatiotemporal decreases of nutrients and chlorophyll-a in the western North Pacific surface mixed layer from 1971 to 2000. Journal of Oceanography, 61, 1011-1016.  
  • Nakano, Y., Watanabe, Y. W. (2005): Reconstruction of pH in the surface seawater over the North Pacific Basin by using temperature and chlorophyll-a. Journal of Oceanography, 61, 673-680.
  • Wakita, M., Watanabe, S., Watanabe, Y. W., Ono, T., Tsurushima, N., Tsunogai, S. (2005): Decadal change in dissolved inorganic carbon at Station KNOT in the subarctic western North Pacific. Journal of Oceanography, 61, 129-139.
  • Emerson, S., Watanabe, Y. W., Ono, T., Mecking, S. (2004): Temporal trends in apparent oxygen utilization in the upper theromocline of the North Pacific. Journal of Oceanography, 60, 139-147.
  • Sabine, C., Feely, R. A., Watanabe, Y. W., Lamb, M. F. (2004): Temporal evolution of the North Pacific Ocean carbon cycles. Journal of Oceanography, 60, 5-15. 
  • Watanabe, Y. W., Wakita, M., Maeda, N., Ono, T., Gamo, T. (2003): Synchronous bidecadal periodic changes of oxygen, phosphate and temperature between the Japan Sea deep water and the North Pacific intermediate water. Geophysical Research Letters, 30(24), 2273, doi:10.1029/2003GL018338.
  • Wakita, M., Watanabe, Y. W., Watanabe, S., Noriki, S., Wakatsuchi, K.(2003): Oceanic uptake rate of anthropogenic CO2 in the subpolar marginal sea: The Sea of Okhotsk. Geophysical Research Letters, 30(24), 2252, doi:10.1029/2003GL018057.  
  • Tanaka, T., Watanabe, Y. W., Watanabe, S., Noriki, S., Tsurushima, N., Nojiri, Y. (2003): Oceanic Suess effect of δ 13C in subpolar region: the North Pacific. Geophysical Research Letters, 30(22), 2159, doi:10.1029/2003/GL0108503.     
  • Watanabe, Y. W., Shimamoto, A., Ono, T. (2003): Comparison of time-dependent tracer ages in the western North Pacific: Oceanic background levels of SF6, CFC-11, CFC-12 and CFC-113. Journal of Oceanography, 59, 719-730.
  • Lamb, M. F., Sabine, C. L., Feely, R. A., Wanninkhof, R., Key, R. M., Johnson, G. C., Millero, F. J., Lee, K., Peng, T. H., Kozyr, A., Bullister, J. L., Greeley, D., Byrne, R. H., Chipoman, D. W., Dickson, A. G., Goyet, C., Gernther, P. R., Ishii, M., Johnson, K. M., Keeling, C. A., Ono, T., Shitashima, K., Tilbrook, B., Takahashi, T., Wallace, D. W. R., Watanabe, Y. W., Winn, C., Wong, C. S. (2002): Internal consistency and synthesis of Pacific Ocean CO2 data. Deep-Sea Research II, 49, 21-58. 
  • Ono, T., Midorikawa, T., Watanabe, Y. W., Tadokoro, K., Saino, T. (2001): Temporal increase of phosphate and apparent oxygen utilization in the subsurface waters of western subarctic Pacific from 1968 and 1998. Geophysical Research Letters, 28(17), 3285-3288, doi:10.1029/2001GL012948.
  • Watanabe, Y. W., Ono, T., Shimamoto, A., Sugimoto, T., Wakita, M., Watanabe, S. (2001): Probability of a reduction in the formation rate of the subsurface water in the North Pacific during the 1980s and 1990s. Geophysical Research Letters, 28(17), 3289-3292, doi:10.1029/2001GL013212. 
  • Ono, T., Watanabe, Y. W., Watanabe, S. (2000): Recent increase of total carbonate in the western North Pacific. Marine Chemistry, 72, 317-328.
  • Watanabe, Y. W., Ono, T., Shimamoto, A. (2000): Increase in the uptake rate of oceanic anthropogenic carbon in the North Pacific determined by CFC age. Marine Chemistry, 72, 297-315.
  • Xu, Y., Watanabe, Y. W., Aoki, S., Harada, K. (2000): Simulation of storage of anthropogenic carbon dioxide in the North Pacific using an ocean general circulation model. Marine Chemistry, 72, 221-238.
  • Ono, T., Watanabe, Y. W., Sasaki, K. (2000): Annual anthropogenic carbon transport into the North Pacific Intermediate Water through Kuroshio/Oyashio Interfrontal Zone: An estimation derived from the CFCs distribution. Journal of Oceanography, 56, 675-689.
  • Takahashi, Y., Matsumoto, E., Watanabe, Y. W. (2000): The distribution of delta C-13 in total dissolved inorganic carbon in the central North Pacific along 175oE and implications for anthropogenic CO2 penetration. Marine Chemistry, 69, 237-251.
  • Takahashi, Y., Matsumoto, E., Watanabe, Y. W. (1999): Anthropogenic carbon in the upper layer of the North Pacific subtropical gyre along 175oE. Journal of Oceanography, 55, 717-730.
  • Watanabe, Y. W., Ono, T., Harada, K., Fukasawa, M. (1999): A preliminary study of oceanic bomb radiocarbon inventory in the North Pacific during the last two decades. Journal of Oceanography, 55, 705-716. 
  • Tsubota, H., Ishizaka, J., Nishimura, A., Watanabe, Y. W. (1999): Overview of NOPACCS (Northwest Pacific Carbon Cycle Study). Journal of Oceanography, 55, 645-654. 
  • Watanabe, Y. W., Ishida, A., Tamaki, M., Okuda, K., Fukasawa, M. (1997): Water column inventories of chlorofluorocarbons and production rate of intermediate water in the North Pacific. Deep-Sea Research, 44, 1091-1104. 
  • Watanabe, Y. W., Takahashi, Y., Kitao, T., Harada, K. (1996): Total amount of oceanic excess CO2 taken from the North Pacific subpolar region. Journal of Oceanography, 52, 301-312.
  • Watanabe, Y. W., Harada, K., Ishikawa, K. (1995): Dilution of North Pacific Intermediate Water studied with chlorofluorocarbons. Journal of Oceanography, 51, 133-144.
  • Watanabe, Y. W., Harada, K., Ishikawa, K. (1994): Chlorofluorocarbons in the central North Pacific and southward spreading time of North Pacific Intermediate Water. Journal of Geophysical Research, 99, 25195-25213.
  • Tsunogai, S., Watanabe, Y. W., Harada, K., Watanabe, S., Saito, S., Nakajima, M. (1993): Dynamics of the Japan Sea deep water studied with chemical and radiochemical tracers. p.105-119. In: T. Teramoto (Editor), Deep Ocean Circulation, Physical and Chemical Aspects, Elsevier, Netherlands. 
  • Watanabe, Y. W., Watanabe, S., Tsunogai, S. (1991): Tritium in the north-western North Pacific. Journal of Oceanographic Society of Japan, 47, 80-93.
  • Watanabe, Y. W., Watanabe, S., Tsunogai, S. (1991): Tritium in the Japan Sea and the renewal time of the Japan Sea deep water. Marine Chemistry, 34, 97-108.