IDAO (Ice-Diminished Arctic Ocean) Data Sets – from a Future Projection
Overview:
The IDAO Data Sets are based on the scenario 2 projection described in detail here. These data sets include projected arctic sea ice thickness and concentration, and more…
Variables:
| Variable | Variable namein programs | Dimension | Unit | File name |
| Sea ice thickness | heff | 2-D | m | heff.H<yyyy> |
| Sea ice concentration | area | 2-D | area.H<yyyy> | |
| Ocean heat flux used to melt ice, unit: (meter of ice)/s | oflux | 2-D | m/s | oflux.H<yyyy> |
| Sea surface height | ssh | 2-D | cm | ssh.H<yyyy> |
| Ocean surface salinity | osali1 | 2-D | psu | osali1.H<yyyy> |
| Ocean salinity of first 10 levels | osali1_10 | 3-D | psu | osali1_10.H<yyyy> |
| Ocean surface temperature | otemp1 | 2-D | C | otemp1.H<yyyy> |
| Ocean temperature of first 10 levels | otemp1_10 | 3-D | psu | otemp1_10.H<yyyy> |
| Ocean velocity at 15 m depth, u & v | uo2 | 2-D | cm/s | uo2.H<yyyy> |
Grid:
Grid Parameters:
| Grid configuration | Generalized curvilinear coordinate system |
| Grid Size: | 360 x 120 |
| Spatial Coverage | 45o N – 90o N |
| Spatial Coverage | The grid domain is shown here |
| lon and lat for scalar fields | grid.dat |
| lon and lat for vector fields | grid.dat.pop |
| angle between latitude line and grid cell x-coordinate line | alpha.fortran.dat |
Temporal Coverage
Currently monthly data from 1/1978 to 12/2004. Each file contains 12 monthly 2-D or 3-D fields.
Data Format:
The data are flat binary files (no headers) consisting of single-precision floating-point numbers. The data were written as unformatted direct access files on a Linux PC cluster. Byte order may have to be changed if you are using a machine using a different byte order (e.g. HP workstations ). A FORTRAN program demonstrating how to read sea ice thickness and velocity and grid information is provided (read_hi_uice.f).
An IDL program demonstrating how to read scalar fields and grid information is also provided (read_draw_hi.pro). Another IDL routine (read_draw_uice.pro)
is provided to read vector fields and vector grid information. It also plots ice velocity on a spherical coordinate system using the angle between the latitude line
and the grid cell x-coordinate line (alpha.fortran.dat). The structure of the data sets should be apparent from these routines. Please let us know if you have difficulty reading the data.
Utilities:
read_hi_uice.f : FORTRAN program to read sea ice thickness and velocity and grid information, can be used to read other scalar and vector fields
read_draw_hi.pro : IDL program to read and plot sea ice thickness, can be used to read other scalar fields such as ice concentration and snow depth
read_draw_uice.pro : IDL program to read and plot sea ice velocity , can be used to read and plot other vector fields such as ocean velocity
colorbar.pro: IDL routine for drawing color bar
con_clr.pro: IDL routine for setting colors
redblue.pro: IDL routine for setting red and blue colors
LLtoXY.pro: IDL routine for plotting vectors
LLtoXY_s.pro: IDL routine for plotting vectors
XYtoLL.pro: IDL routine for plotting vectors
XYtoLL_s.pro: IDL routine for plotting vectors
heads.pro: IDL routine for plotting vectors
levels_25_t_360_120: model grid mask; ocean levels > 0, land < 0
Data Access:
You can access the data via FTP by entering ‘ftp pscftp.apl.washington.edu’, then ‘anonymous’ as your log name, and your email address as password. After entering the web site, go to zhang/IDAO/retrospection.
You can also access the data from here: ftp://pscftp.apl.washington.edu/zhang/IDAO/future_projection
If you are downloading the data, please e-mail us at zhang©apl•washington•edu (zhang©apl•washington•edu) we can update you on changes, bugs etc.
Attribution:
We’d appreciate your reference to the following paper for using the data:
Zhang, Jinlun and D.A. Rothrock: Modeling global sea ice with a thickness and enthalpy distribution model in generalized curvilinear coordinates, Mon. Wea. Rev. 131(5), 681-697, 2003.