Report on the International Workshop for Large-scale Research Cruises

Transcription

1 Report on the International Workshop for Large-scale Research Cruises 1. General information Cruise Title: DIO Delve into the Indian Ocean Moderator s Name:K. Takai, K. Katsumata Moderator s Department:Department of Subsurface Geobiological Analysis and Research, Research and Development Center for Global Change Required cruise days (round-trip):approximately 300 days Major Survey Area:Indian Ocean Brief description of the scientific objectives and survey plan of the cruise(s) (up to 200 words) Indian Ocean is the least known among the three oceans; Pacific, Atlantic and Indian. After JAMSTEC large-scale cruise planning workshop, this grand cruise, named as Delve into the Indian Ocean (DIO), is proposed with a common ambition to know major unknowns in the world ocean and will be an important contribution to the international framework of 2 nd International Indian Ocean Expedition (IIOE 2) developed by the Intergovernmental Oceanographic Commission (IOC) and the Scientific Committee on Oceanic Research (SCOR) of UNESCO. The DIO cruise consists of three major initiatives and areas to explore: (1) one is the study of the evolution of the Indian Ocean, its' structure and geological history, and its biosphere based on investigations of water-driven mantle heterogeneity, geodynamo, tectonics, crustal hydrothermal activities and biodiversity and biogeography of deep-sea microbial and faunal communities in the Central Indian Ridge, Southwestern Indian Ridge, hotspots and their flanks; (2) another is the multidisciplinary exploration of geological and oceanographic settings in the eastern Indian Ocean (EIO) such as the seismogenic structures and the ocean upwelling functions in the EIO and the hypoxia biogeochemistry in the Bay of Bengal and the Andaman Sea; (3) a further one is to clarify response of Indian Ocean to the global climate change based on oceanographic observation in the southern and central Indian Ocean. The DIO cruise is planned as a 3-years project: in the first year (e.g., 2016), R/V Yokosuka or Kairei with HOV Shinkai6500 or ROV Kaiko MarkIV will pursue the initiatives (1) and (2) for 100 days; in the second year, R/V Yokosuka or Kairei with HOV Shinkai6500 or ROV Kaiko MarkIV will continue to address the initiatives (1) and (2) for 50 days and R/V Mirai will be in charge of the initiative (3) for 50 days; finally in the third year, a JAMSTEC new ship will complete all the initiatives over 100 days. Keywords (up to 5): IIOE 2, mantle to biodiversity, climate change, seismogenic zone, hypoxia Relationships to the JAMSTEC Mid-term program: Directly connected with (1) Research and Development for Submarine Resources (2) Research and Development for Global Change, (3) Research and Development for Earthquake and Tsunami, and (4) Research and Development for Marine Biosciences declared in the JAMSTEC Mid-term program 1

2 2. Co-proponent *Please add lines if necessary 1 Lynne Talley Name Organization Country Remarks Scripps Institution of Oceanography USA 2 Nobukazu Seama Kobe University Japan 3 Dass Bissessur 4 Olivier Pasnin Oceanography Oceanography 5 Greg Cowie University of Edinburg UK 6 Yasushi Ishihara JAMSTEC Japan 7 Cecilia McHugh Queens College, City Univ. of NY USA 8 Toshiya Kanamatsu JAMSTEC Japan 9 N.D. Hananto Indonesian of Science Indonesia 10 Chong Chen Oxford University UK 11 Greg Moore University of Hawaii USA 12 Yudi Nurul Ihsan Padjadjaran University Indonesia 13 Iwao Ueki JAMSTEC Japan 14 Shinsuke Kawagucci JAMSTEC Japan 15 Marie-Helen Cormier University of Rhode Island USA 16 Toshiya Fujiwara JAMSTEC Japan 17 Ken Takai JAMSTEC Japan 18 Katsuro Katsumata JAMSTEC Japan 19 Prerna Roy Oceanography 20 Arnaud Nicolas Oceanography 21 Yukio Masumoto University of Tokyo Japan 22 Jerome Dyment Institut de Physique du Globe de France Paris 23 Kyoko Okino AORI, University of Tokyo Japan 24 Tomoaki Morishita Kanazawa University Japan 25 Yoshifumi Nogi NIPR Japan 26 Wajih Naqvi National of India Oceanography of India 27 Hirsohi Kitazato JAMSTEC Japan 2

3 3. Scientific Objectives of the cruise(s) We propose here a series of grand cruise project named as Delve into the Indian Ocean (DIO) for comprehensive and interdisciplinary understanding of the least-explored ocean, the Indian Ocean, for the evolution of whole Indian Ocean and its biosphere, the structures and functions of unique geological and oceanographic settings in the eastern Indian Ocean (EIO) and the response of Indian Ocean to the global climate change. The cruise comprises six components, each originating from pre-proposals submitted under different disciplines. (1) Road back to Vasco Da Gama (L14-05: Takai et al.; L14-16: Rogers et al.; L14-45: Copley et al.; L14-56: Bissessur et al.). The scientific objectives of this theme are to further extend our understanding of deep-sea hydrothermal systems and their dark ecosystems in the Indian Ocean and the southern Atlantic Ocean. The genetic connectivity of the species will also be assessed for the demarcation of potential offshore MPAs. We will also characterize the structure of the southern part of the Mascarene Plateau and the structure and geological history of the Rodrigues Ridge and investigate the historical climate variability of the region. (2) Observational study of physical and biogeochemical variabilities in the Indian and Southern Oceans (L14-31, Talley et al.). The scientific objectives of this theme are to understand climate-relevant patterns in carbon uptake, upwelling and mixing structure and net community production in the Indian Ocean and Indian sector of the Southern Ocean. (3) Volatiles in the Earth and dynamic Cretaceous (L14-49: Seama et al.; L14-35: Dyment et al.). The scientific objectives of this theme are to clarify heterogeneous volatile content and migration in the mantle and geomagnetic history in the crust of the Indian Ocean and to estimate the impacts on the evolution of Indian Ocean. (4) Hypoxia and sediment biogochemistry of the Bay of Bengal: Benthic ecology and process studies across contrasting margins (L14-59: Cowie et al.). The scientific objective of this theme is to characterize the benthic community structures, functions and successions in different settings of hypoxia in the Bay of Bengal. (5) Intensive observation cruise for eastern Indian Ocean upwelling research initiative (L14-54: Matsumoto et al.; L14-14: Ihsan et al.). The scientific objectives of this theme are to characterize the monsoonal forcing upwelling in the eastern Indian Ocean and to estimate the impact of upwelling and oxygen-depletion on the nutrient distributions, biogeochemical processes, productivity and ecosystem dynamics. (6) Sunda margin geohazards assessment: from passive to active seismological imaging (L14-01: McHugh et al.; L14-41: Singh et al.; L14-57: Cummins et al.). The scientific objectives of this theme are to collect high-resolution bottom and sub-bottom geophysical structures along the Sunda subduction zone and to know the history and the future risk of tunami-earthquake in the eastern Indian Ocean area. These components are grouped into three expedition units or initiatives based on the the scientific objective synergy the observation and survey plans and platforms and the target areas: (1) & (3) can be conducted together in the in the Central Indian Ridge, Southwestern Indian Ridge, hotspots and their flanks; (4), (5) & (6) may have geographic affinity in the eastern Indian Ocean and Bay of Bengal; and (2) require an independent observation strategy for physical oceanography. However, all the proponents are strongly willing to establishing a comprehensive and interdisciplinary ocean exploration to challenge major unknowns in the Indian Ocean. 3

4 4. Survey Plan of the cruise(s) (maps required) The DIO cruise is best implemented by three platform types: (1) surface ships (R/V Yokosuka or Kairei) with deep-sea vehicles (HOV Shinkai6500 or Kaiko MarkIV); (2) oceanographic ship (R/V Mirai) with a full array of mooring, Argo buoy and oceanographic and atmospheric observation tools; and (3) a new JAMSTEC ship capable of both operations. Effectively to use these different platforms and quite long round-trip tracks of research ships from Japan to various sites in the Indian Ocean, three years of expedition plan will be required. Although the feasibility and the detail planning of each of the expeditions will be discussed and optimized among the proponents of DIO cruise and with the JAMSTEC ship operation committees and department, we provide here a brief survey plan of the cruise to cover all the scientific objectives and target areas (Figure 1). In the first year (probably in 2016): R/V Yokosuka or Kairei with HOV Shinkai6500 or ROV Kaiko MarkIV will first visit the Andaman Sea to conduct the seafloor observation for hydrothermal systems (8 days on sites and travels tentatively counted) and then will visit the Bay of Bengal (including the Lombok Basin) for seismogenic zone research and hypoxia ecosystem research (25 days) under the international framework as shown by yellow lines in Figure 1. Next, parts of the researches for the Indian Ocean mantle heterogeneity and the CIR deep-sea hydrothermal vents and ecosystems will be conducted by multidisciplinary onboard scientists from India to (19 days). Then, parts of the researches for the SWIR deep-sea hydrothermal vents and ecosystems and the geomagnetic survey in the northern flank of SWIR will be done (24 days) and move to the western Australia. Finally, parts of the oceanographic observations of upwelling in the EIO and the geophysical surveys in the southern parts of the Sunda Trench will be conducted before returning to Japan (24 days). The several parts of this first year cruise may contain the themes already approved themes by JAMSTEC (e.g., the CIR and SWIR hydrothermal vents and ecosystems research). In the second year: Two platforms will be operated for two legs. Leg 1 using R/V Kairei and ROV Kaiko MarkIV will visit the Indian Ocean but start with the geophysical survey for the seismogenic zones of the Sunda subduction zone as shown by purple lines in Figure 1 (15 days). Next, parts of the researches for the Indian Ocean mantle heterogeneity and the CIR deep-sea hydrothermal vents and ecosystems will be conducted by multidisciplinary onboard scientists from Indonesia to, including recovery of instruments deployed in the first year (20 days). Finally, parts of the oceanographic observations of upwelling in the EIO and the geophysical surveys in the Sunda Trench will be conducted before going back to Japan (15 days). Leg 2 using R/V Mirai will conduct the oceanographic observation along E80 from Kerguelen to Sri Lanka (40 days) and then will take in charge of geophysical surveys in the northern parts of the Sunda Trench (10 days). In the third year: JAMSTEC new ship will finalize the DIO cruise. First, the expedition will be conducted for the oceanographic observation along E57 from t o the off coast of Antarctic (45 days), and then the geomagnetic survey in the southern flank of SWIR and the seafloor observation of the SWIR hydrothermal vents and ecosystems will be done (25 days) to move to the South Africa. In the way back to Japan, parts of the oceanographic observations of upwelling in the EIO and the geophysical surveys in the Sunda Trench will be conducted (30 days). 4

5 5. Relevance to other scientific projects in Japan and/or abroad The DIO cruise is primarily based on the JAMSTEC Mid-term program and the JAMSTEC COE leadership of international ocean exploration. On the other hand, this cruise will represent the significant JAMSTEC s and Japanese contribution to 2nd International Indian Ocean Expedition (IIOE 2) developed by the Intergovernmental Oceanographic Commission (IOC) and the Scientific Committee on Oceanic Research (SCOR) of UNESCO to celebrate the 50 th anniversary of International Indian Ocean Experiment. In addition, this cruise will greatly contribute many other international oceanographic, earth science and marine biological programs such as XXX, InterRidge (e.g., Circum-Antarctic Ridges WG), IODP and XXXX. 6. Remarks Figure 1. A map showing a survey plan of the DIO cruise to cover all the scientific objectives and target areas. Yellow lines, circles and boxes indicate the proposed survey plan in the first year for the expedition with R/V Yokosuka or Kairei with HOV Shinkai6500 or ROV Kaiko MarkIV. Purple lines, circles and boxes indicate the proposed survey plan in the second year for the expedition with R/V Kairei with ROV Kaiko MarkIV and grey lines show the proposed survey plan in the second year for the expedition with R/V Mirai. White lines, circles and boxes are the proposed survey plan in the third year for the expedition with JAMSTEC new ship. 5

6 Appendix Maps in each of the pre-proposals that are finally merged into the DIO cruise. 6