Research Vessel "MIRAI" during Fiscal Year 2000
MR00-K03 Observational studies on the Material Cycle in the High Latitude
Sea.
Objectives : The northern North Pacific, especially its western part, has
been attracting attention of chemical oceanographers because of its importance
in global biogeochemical cycles of carbon and its related materials, which have
a great impact to the climate change of the earth. In addition, physical oceanographers
have been interested in that region with respect to the formation of the North
Pacific Intermediate Water. Despite its importance, there has been few systematic
survey to cover the temporal and spatial variation of biogeochemical processes
in the area. Main goal of this study is to clarify the behavior of carbon and
its related materials in the area, and then to estimate the impact of high latitude
seas on the global climate change.
MR00|K04 Observationl Studies on Air Sea Interaction.
Objectives : Water and heat flux is one of the most important factor to understand
the ENSO(El Nino and Southern Oscillaticn ) and the Mcnsccn which affect the
global climate. Especially the precipitation is the key phenomena playing the
important role for the water and heat flux. So, the interaction between the
ocean and the atmosphere are studied focusing on the precipitation. Mainly by
using powerful tool shipboard C-band Doppler radar, the precipitation mechanism
of the convection which develop in the intertropical convergence zone (ITCZ)
and the influence of the precipitation onto the ocean surface structure will
be surveyed.
MR00-K05 The Subtropical Gyre and the Subpolar Gyre in the North Pacific
Ocean.
Objectives : Oceanic conditions in the subtropical and subarctic gyres, especially
in and around the Kuroshio Extension, are thought to be important to the North
Pacific decadal/interdecadal climate variabilities. In terms of global heat
budget, the ocean in this region transfers the heat obtained in the tropis to
the atmosphere. The area could also be a reservoir of greenhouse gases as anthropogenic
CO2 by deep oceanic convection in winter season which may convey these gasses
to deep ocean.
MR00-K06 Observational Studies in the Arctic Ocean
Objectives : The continental shelf in the Arctic Ocean is a place where remarkable
positive and negative buoyancy flux is being supplied due to an inflow of fresh
water, melting and formation of sea ice and etc. Also, a cold halocline water
exists between the surface mixed layer and the Atlantic Water in a wide range
of the Arctic Ocean.
The lower layer of this cold halocline contains maximum silicate concentration
and minimum dissolve oxygen, therefore the origin of such water mass may exists
on the continental shelf. The formation, maintenance, and variations of the
cold halocline may have significant influence on a oceanic structure in the
Arctic Ocean.
Toward the understanding of various processes in the cold halocline, we have
to know shelf brake processes such as instability, eddy formation, water exchange
and water mass formation due to surface cooling on the shelf and in the canyons
as well.
The purposes of this study are to collect dates covering decades scale on ocean
structure, buoyancy flux, and year to year variations of sea ice extent and
so on, then carry out assessment on influence of shelf - basin interaction processes
to the climate system in the Arctic Ocean.
MR00-K07 Observational Studies in the Western Tropical Pacific Ocean and
Observational @@@@@@@@@Studies on Air Sea Interaction
Objectives : For the purpose of understanding the role of the warm water pool
to EI Nino and Asian Monsoon, which affect the social and economical activities
in the East Asian countries including Japan, we will conduct the observational
studies on the oceanic and atmospheric variabilities.
The major theme is to clarify the heat, freshwater and momentum balances in
the surface mixed layer in the warm water pool in the western Pacific Ocean
as well as the eastern Indian Ocean. In this study, we will also expect to understand
the role of salinity, horizontal advection of heat and freshwater, and equatorial
waves such as Kelvin waves to the change of the surface mixed layer. We will
also study how the Pacific Ocean and the Indian Ocean interact mutually by exchange
of heat and fresh water through the Indonesian Seas.
We will also conduct atmospheric observation mainly using a Doppler radar system
(C-band) to understand the cloud systems over the tropical ocean.
MR00-K08 Observational studies on Primary Productivity in the Equatorial
Pacific Ocean
Objectives : The equatorial Pacific has distinguished characteristics, those
are it occupies a large region of the world's ocean and the warmest water of
the planet exists there. The western equatorial Pacific contains so-called warn
water pool. Nitrate is depleted there and primary production is small. In the
central and eastern equatorial Pacific, vertical flux of nutrients is enhance
due to Quasi-stationary up welling caused by equatorial divergence and consequently
chlorophyll a concentration and primary production rate increased along the
equator. However, primary production and biomass are not as high as would be
expected from the flux of nutrients could support. This is called high nutrient
low chlorophyll situation. Since this east to west asymmetry is affected by
ENSO event, there is a significant variability in physical characters on seasonal-interannual
scale with impact to biogeochemistry, as well potentially with the similar scale
of variability. The objective of our cruise is to investigate the mechanism
of this biogeochemical variability especially in the western equatorial Pacific.
MR01-K01 Observational Studies in the Western Tropical Pacific Ocean
Objectives : 'For the purpose of understanding the role of the warm water
pool to EI Nino and Asian Monsoon, which affect the social and economical activities
in the East Asian countries including Japan, we will conduct the observational
studies on the oceanic and atmospheric variabilities.
The major theme is to clarify the heat, freshwater and momentum balances in
the surface mixed layer in the warm water pool in the western pacific Ocean
as well as the eastern Indian Ocean. In this study, we will also expect to understand
the role of salinity, horizontal advection of heat and freshwater, and equatorial
waves such as kelvin waves to the change of the surface mixed layer. We will
also study how the Pacific Ocean and the Indian Ocean interact mutually by exchange
of heat and fresh water through the Indonesian Seas.