Arctic Research Directory

ID-22 :   Arctic Ocean high-resolution model nested with global OGCM




Arctic Ocean high-resolution model nested with global OGCM


We are developing a global ocean model with a two-way nested-grid system, in which the horizontal resolution of the Arctic Ocean is 5 km or higher. The OGCM used here is COCO version 4.9. The horizontal resolution of the global (or outer) model, which has been already set up, is approx. 1/4 degree.

Computing Environment

Earth Simulator

Principal Investigator

Hiroyasu Hasumi
Atmosphere and Ocean Research Institute, The University of Tokyo

Funding Information Other Funding Details

ArCS Theme 5 : Study on Arctic climate predictability

Data Information

Model Name
COCO version 4.9
Abstract (Brief description of the experiment contents (initial conditions, boundary conditions, etc.))
(1) Simulations performed by a global ice-ocean model with high resolution in northern high latitudes in order to improve the reproducibility of the Arctic Ocean in global climate models. Two-way nested grid version of ice-ocean model COCO (Kurogi et al., 2013; Kurogi et al., 2016) is used. The inner model domain covers roughly the area to the north of 61N and is nested into the outer model domain, which covers the whole globe. The horizontal resolution of the inner and outer models are approximately 2.5 km and 0.25 degree, respectively. (2) To make the initial condition, only the outer model is spun up with restoring temperature and salinity below 50 m depth to PHCv3 climatology (Steele et al., 2001). The result is then interpolated to the inner model domain. (3) The atmospheric dataset JRA55-do (Tsujino et al., 2018) is used to drive the nested model. When a simulation is performed under a future climate condition, the data is modified depending on the difference between future projection and present atmospheric condition. (4) Total data size will be 20 TB per case (10 years). Grid Information Dimension Size (slice number of the dimension) row: 7200(inner), 1440(outer) column: 1280(inner), 1280(outer) vertical: 62 Resolution Unit row; approx. 2.5 km (inner), 0.25 deg. (outer) column: approx. 2.5 km (inner), 0.25 deg. (outer) vertical: 10 in the uppermost 50 m, 31 in the uppermost 500 m.
Temporal Extent
Begin Date2041-01-01
End Date2050-12-31
Temporal Characteristics5 daily and monthly
Geographic Bounding Box
North bound latitude90.0
West bound longitude0.0
Eastbound longitude360.0
South bound latitude-90.0


RollContact PersonNameYoshiki KomuroAffiliationJapan Agency for Marine-Earth Science and
Data Registration
02:58 on Wed June 29, 2016
Last Update
04:44 on Fri July 5, 2019