JRA-3Q Data Format
Model grid data

December 2022
Information Infrastructure Department
Japan Meteorological Agency

Contents
JRA-3Q Data Format Model grid data .......................................................................................... 1
1.

Introduction ........................................................................................................................... 4

2.

Product overview................................................................................................................... 4

3.

GRIB2 format ........................................................................................................................ 4
Section 0 – Indicator section ..................................................................................................... 4
Section 1 – Identification section .............................................................................................. 5
Section 2 – Local use section .................................................................................................... 5
Section 3 – Grid definition section ............................................................................................ 6
Section 4 – Product definition section....................................................................................... 7
Product definition template 4.0 – analysis or forecast at a horizontal level or in a horizontal
layer at a point in time ........................................................................................................... 7
Product definition template 4.8 – average, accumulation and/or extreme values or otherstatistically processed values at a horizontal level or in a horizontal layer in a continuous or
non–continuous time interval ................................................................................................ 7
Section 5 – Data representation section .................................................................................... 8
Data representation template 5.0 – Grid point data – simple packing................................... 9
Data representation template 5.3 – Grid point data – complex packing and spatialdifferencing ........................................................................................................................... 9
Section 6 – Bit-map section ...................................................................................................... 9
Section 7 – Data section ............................................................................................................ 9
Data template 7.0 – Grid point data – simple packing ........................................................ 10
Data template 7.3 – Grid point data – complex packing and spatial differencing............... 10
Section 8 – End section ........................................................................................................... 10

4.

Output parameters ............................................................................................................... 11
4.1.

Surface analysis fields (anl_surf) ................................................................................. 11

4.2.

Snow analysis fields (anl_snwlev) ............................................................................... 12

4.3.

Snow depth analysis fields (anl_snow) ........................................................................ 12

4.4.

Isobaric analysis fields (anl_p) .................................................................................... 12

4.5.

Model level analysis fields (anl_mdl) .......................................................................... 13

4.6.

Isentropic analysis fields (anl_isentrop) ...................................................................... 13

4.7.

Land surface analysis fields (anl_land) ........................................................................ 13

4.8.

Two-dimensional instantaneous diagnostic fields (fcst_surf) ...................................... 15

4.9.

Snow forecast fields (fcst_snwlev) .............................................................................. 16

4.10.

Isobaric forecast fields (fcst_p) ................................................................................ 162

4.11.

Model level forecast fields (fcst_mdl) ..................................................................... 17

4.12.

Land surface forecast fields (fcst_land) ................................................................... 17

4.13.

Ocean surface boundary conditions (bnd_ocean) .................................................... 18

4.14.

Two-dimensional average diagnostic fields (fcst_phy2m) ....................................... 19

4.15.

Model level average diagnostic fields (fcst_phy3m) ............................................... 20

4.16.

Land surface average diagnostic fields (fcst_phyland) ............................................ 21

4.17.

Two-dimensional extreme fields (minmax_surf) ..................................................... 21

5.

Invariant data ....................................................................................................................... 21
5.1.

Surface geopotential (TL479_surf) .............................................................................. 21

5.2.

Land surface information (TL479_land)...................................................................... 21

6.

Type of vegetation ............................................................................................................... 22

7.

Grid ..................................................................................................................................... 22
7.1.

8.

Quasi-regular Gaussian latitude/longitude grid ........................................................... 22

Vertical coordinates ............................................................................................................. 25
8.1.

Model level (Hybrid level) ........................................................................................... 25

9.

Physical constants ............................................................................................................... 28

10.

Climatological normals .................................................................................................... 29

10.1.

Daily mean smooth climatological normals ............................................................. 29

10.2.

Monthly mean climatological normals ..................................................................... 29

References ................................................................................................................................... 29

3

1.

Introduction
This document provides an overview of products (model grid data) stemming from the Japanese

Reanalysis for Three Quarters of a Century (JRA-3Q) conducted by the Japan Meteorological
Agency for the period from the late 1940s onward (Kobayashi et al. 2021).

2.

Product overview
1. Quasi-regular Gaussian latitude/longitude grids
2. Data points: 342,816
3. Grid spacing: approx. 40 km
4. Time interval: every 6 hours (hourly or daily for some types), monthly statistics
5. Data volume: approx. 3.5 TB/year
6. Data format: Gridded Binary Edition 2 (GRIB2)

3.

GRIB2 format
The JRA-3Q product is encoded with GRIB2 as outlined below.
See the Manual on Codes I.2 (WMO 2022) for the information quoted in the tables here.

Section 0 – Indicator section
Octet No.
1-4
5-6
7
8
9-16

Contents
GRIB (coded according to the International Alphabet No.
5)
Reserved
Discipline - GRIB Master table number (see Code table
0.0)
GRIB edition number
Total length of GRIB message in octets (including
Section 0)

4

Value

Notes

GRIB

******
2******

Section 1 – Identification section
Octet No.

Contents

Value

Notes

1-4

Length of section in octets

21

5

Number of section
Identification of originating/generating centre (seeCommon Code table C-11)
Identification of originating/generating subcentre(allocated by originating/ generating centre)
GRIB master table version number (see Common Code table
C-0)
Version number of GRIB Local tables used to augment
Master tables (see Code table 1.1)
Significance of reference time (see Code table 1.2)

1******

Year (4 digits)******

15

Month******

16

Day******

17

Hour******

18

Minute019SecondProduction status of processed data in this GRIB message(see Code table 1.3)
Type of processed data in this GRIB message (see Codetable 1.4)

0

6-7
8-9
10
11
12
13-14

20
21

34

Tokyo (RSMC), Japan
Meteorological Agency

241 Reanalysis project
21

Version implemented on 2
May 2018

1

3 Re-analysis products******

Section 2 – Local use section
Octet No.

Contents

Value

Notes

1-4

Length of section in octets

17
2

5

Number of section

6-7

Local use

8-9

Local use

10-11

Local use

12-13

Local use

14-17

Stream******

5

Section 3 – Grid definition section
Notes

Value

Contents

Octet No.

1032

1-4

Length of section in octets

5

Number of section

3

6

Source of grid definition (see Code table 3.0)0342816

7-10

Number of data points

11

Number of octets for optional list of numbers

12

13-14

Interpretation of list of numbers (see Code table 3.11)

Grid definition template number (see Code table 3.1)

15

Shape of the Earth (see Code table 3.2)

16

Scale factor of radius of spherical Earth

17-20

Scaled value of radius of spherical Earth21

Scale factor of major axis of oblate spheroid Earth

22-25

Scaled value of major axis of oblate spheroid Earth26

Scale factor of minor axis of oblate spheroid Earth

27-30

Scaled value of minor axis of oblate spheroid Earth

31-34

Ni - number of points along a parallel

35-38

Nj - number of points along a meridian

39-42

47-50

Basic angle of the initial production domain
Subdivisions of basic angle used to define extreme
longitudes and latitudes, and direction increments
La1 - latitude of first grid point

51-54

Lo1 - longitude of first grid point

43-46

Specified in Code table
3.1

2
Numbers define number ofpoints corresponding tofull coordinate circles(i.e. parallels),coordinate values oneach circle are multiple
1of the circle mesh, andextreme coordinate
values given in griddefinition (i.e. extreme
longitudes) may not bereached in all rows
Gaussian40
latitude/longitude
Earth assumed spherical
1 with radius specified(in m) by data producer
06371000480
089713240
056-59

La2 - latitude of last grid point

i direction increments
not givenj direction increments
not given
0x00 Resolved u- and vcomponents of vector
quantities relative toeasterly and northerly
directions-89713240

60-63

Lo2 - longitude of last grid point

359625000

64-67

Di - i direction increment

68-71

N - number of parallels between a pole and the Equator

55

72

73-nn

Resolution and component flags (see Flag table 3.3)

Scanning mode (see Flag table 3.4)

List of number of points along each meridian or parallel

6

240
Points of first row orcolumn scan in the +i(+x) direction
Points of first row or
0x00 column scan in the –j (–y) direction
Adjacent points in i (x)direction areconsecutive
7.1.Quasi-regular
GaussianSection 4 – Product definition section
Octet No.

Contents

1-4

Length of section in octets

5

Number of section

6-7
8-9

Value

Notes

******
4

Number of coordinate values after template or number of
information according to 3D vertical coordinate GRIB2
message
Product definition template number (see Code table 4.0)0******

Product definition template (see template 4.X, where X
10-xx
is the product definition template number given in
octets 8-9)
Optional list of coordinate values or vertical grid[xx+1]-nn
information

8.1.Model level (Hybrid
level)

From the tenth octet onward, product definition template 4.8 is used for two-dimensional
average diagnostic fields (fcst_phy2m), model level average diagnostic fields (fcst_phy3m), land
surface average diagnostic fields (fcst_phyland), two-dimensional extreme fields (minmax_surf)
and monthly statistics (all types), and 4.0 is used elsewhere.
Product definition template 4.0 – analysis or forecast at a horizontal level or in a horizontal
layer at a point in time
Octet No.

Contents

Value

Notes

10

Parameter category (see Code table 4.1)******

11

Parameter number (see Code table 4.2)******

12

Type of generating process (see Code table 4.3)******

13

Background generating process identifier (defined byoriginating centre)

14
15-16
17
18
19-22

Analysis or forecast generating process identifier(defined by originating centre)
Hours of observational data cut-off after reference time
Minutes of observational data cut-off after referencetime
Indicator of unit of time range (see Code table 4.4)

Japanese Reanalysis for
141 Three Quarters of a
Century (JRA-3Q)

65534
0
1 Hour

Forecast time in units defined by octet 18******

23

Type of first fixed surface (see Code table 4.5)******

24

Scale factor of first fixed surface******

25-28

Scaled value of first fixed surface******

29

Type of second fixed surface (see Code table 4.5)******

30

Scale factor of second fixed surface******

31-34

Scaled value of second fixed surface******

Product definition template 4.8 – average, accumulation and/or extreme values or otherstatistically processed values at a horizontal level or in a horizontal layer in a continuous or7non–continuous time interval
Octet No.

Contents

Value

Notes

10

Parameter category (see Code table 4.1)******

11

Parameter number (see Code table 4.2)******

12

Type of generating process (see Code table 4.3)******

13

Background generating process identifier (defined byoriginating centre)

14
15-16

Analysis or forecast generating process identifier(defined by originating centre)
Hours after reference time of data cut-off

17

Minutes after reference time of data cut-off

18

Indicator of unit of time range (see Code table 4.4)

19-22

Japanese Reanalysis for
141 Three Quarters of a
Century (JRA-3Q)

65534
0
1 Hour

Forecast time in units defined by octet 18******

23

Type of first fixed surface (see Code table 4.5)******

24

Scale factor of first fixed surface******

25-28

Scaled value of first fixed surface******

29

Type of second fixed surface (see Code table 4.5)******

30

Scale factor of second fixed surface******

31-34

Scaled value of second fixed surface******

35-36

Year

******

37

Month******

38

Day******

39

Hour******

40

Minute041Secondn - number of time range specifications describing thetime intervals used to calculate the statisticallyprocessed field
Total number of data values missing in statisticalprocess

0

42
43-46

******
047-58 Specification of the outermost (or only) time range over which statistical processing
is done
47
48
49
50-53
54
55-58

Statistical process used to calculate the processed
field from the field at each time increment during thetime range (see Code table 4.10)
Type of time increment between successive fields used in
the statistical processing (see Code table 4.11)
Indicator of unit of time for time range over which
statistical processing is done (see Code table 4.4)
Length of the time range over which statisticalprocessing is done, in units defined by the previous
octet
Indicator of unit of time for the increment between the
successive fields used (see Code table 4.4)
Time increment between successive fields, in units
defined by the previous octet (see Notes 3 and 4)************
1 Hour******
1 Hour******

59-nn These octets are included only if n > 1, where nn = 46 + 12 x n
59-70
71-nn

As octets 47 to 58, next innermost step of processing
Additional time range specifications, included inaccordance with the value of n. Contents as octets 47 to
58, repeated as necessary

Section 5 – Data representation section
Octet No.

Contents

1-4

Length of section in octets

5

Number of section

6-9
10-11
12-nn

Value

Notes

******
5

Number of data points where one or more values are
specified in Section 7 when a bit map is present, total
number of data points when a bit map is absent.
Data representation template number (see Code table 5.0)
Data representation template (see template 5.X, where X
is the data representation template number given in
octets 10-11)8************

From the tenth octet onward, data representation template 5.3 is used for six-hourly, hourly anddaily data, and 5.0 is used for monthly statistics and climatological normals.
Data representation template 5.0 – Grid point data – simple packing
Octet No.

Contents

Value

Notes

12-15

Reference value (R) (IEEE 32-bit floating-point value)******

16-17

Binary scale factor (E)******

18-19

Decimal scale factor (D)Number of bits used for each packed value for simple
packing, or for each group reference value for complex
packing or spatial differencing
Type of original field values (see Code table 5.1)******

20
21******
0 Floating point

Data representation template 5.3 – Grid point data – complex packing and spatial differencing
Octet No.
12-21

Contents

Value

Notes

Same as data representation template 5.0

22Group splitting method used (see Code table 5.4)******

23

Missing value management used (see Code table 5.5)******

24-27

Primary missing value substitute******

28-31

Secondary missing value substituteNG - number of groups of data values into which field is
split
Reference for group widths
Number of bits used for the group widths (after thereference value in octet 36 has been removed)
Reference for group lengths******

Length increment for the group lengths******

True length of last group
Number of bits used for the scaled group lengths (after
subtraction of the reference value given in octets 38-41
and division by the length increment given in octet 42)
Order of spatial differencing (see Code table 5.6)
Number of octets required in the data section to specify
extra descriptors needed for spatial differencing(octets 6-ww in data template 7.3)******

32-35
36
37
38-41
42
43-46
47
48
49

******************************************

Section 6 – Bit-map section
Octet No.

Contents

Value

1-4

Length of section in octets

5

Number of section

6

Bit-map indicator (see Code table 6.0)
Bit-map - Contiguous bits with a bit to data point
correspondence, ordered as defined in Section 3. A bit
set to 1 implies the presence of a data value at thecorresponding data point, whereas a value of 0 implies
the absence of such a value.

7-nn

Notes

******
6************

Section 7 – Data section
Octet No.

Contents

1-4

Length of section in octets

5

Number of section

6-nn

Value

Notes

******
7

Data in a format described by data template 7.X, where X
is the data representation template number given in
octets 10-11 of Section 5.

From the sixth octet onward, data representation template 7.3 is used for six-hourly, hourly and9daily data, and 7.0 is used for monthly statistics and climatological normals.
Data template 7.0 – Grid point data – simple packing
Octet No.
6-nn

Contents
Binary data values - binary string, with each (scaled)data value

Value

Notes

******

Data template 7.3 – Grid point data – complex packing and spatial differencing
Octet No.

Contents
First value(s) of original (undifferenced) scaled data
values, followed by the overall minimum of thedifferences. The number of values stored is 1 greater
6-ww
than the order of differentiation, and the field widthis described at octet 49 of data representation template
5.3
NG group reference values (X1 in the decoding formula),each of which is encoded using the number of bits
specified in octet 20 of data representation template[ww+1]-xx
5.0. Bits set to zero shall be appended where necessary
to ensure this sequence of numbers ends on an octet
boundary
NG group widths, each of which is encoded using thenumber of bits specified in octet 37 of data
[xx+1]-yy representation template 5.2. Bits set to zero shall beappended as necessary to ensure this sequence of numbers
ends on an octet boundary
NG scaled group lengths, each of which is encoded using
the number of bits specified in octet 47 of data[yy+1]-zz representation template 5.2. Bits set to zero shall beappended as necessary to ensure this sequence of numbers
ends on an octet boundary
Packed values (X2 in the decoding formula), where each[zz+1]-nn value is a deviation from its respective group reference
value

Value

Notes

******************************

Section 8 – End section
Octet No.
1-4

Contents“7777” (coded according to the International Alphabet
No. 5)

10

Value
7777

Notes

4.

Output parameters1

4.1.

Surface analysis fields (anl_surf)CodefiguresParameter

0,

1, 64

0,

0,

0,

1, 13

0,

3,

Units

Total column integrated
water vapour

kg m

2 Potential temperature-2

K

Water equivalent ofaccumulated snow depth

kg m-20 PressurePa

0,194,

6 Energy stored in light snow J m-2

0,194,

7 Amount of light snow

kg m

0,

3,

1 Pressure reduced to MSL

Pa

0,

0,

0 Temperature

K

0,

0,

7

0,

1,

0 Specific humidity

kg kg

0,

1,

1 Relative humidity

%

0,

2,

2 u-component of wind

m s

-1

0,

2,

3 v-component of wind

m s

-1

Dewpoint depression (ordeficit)

-2

K
-1

Level
1 (Ground or water
surface): 8 (Nominal
top of the atmosphere)
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)101 (Mean sea level)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground10m)
103 (Specified heightlevel above ground10m)

Note: The saturated vapor pressure used to calculate dewpoint depression (or deficit) andrelative humidity from specific humidity is the value from over liquid water at a temperature of273.15K or higher, over ice at a temperature of 258.15K or lower, and the weighted average ofthe two with proportions linearly dependent on temperatures between 258.15 and 273.15K.

The code figures in the tables indicate discipline, parameter category and parameter number.
Parameter names conform to the notation of the Manual on Codes I.2 (WMO 2022).
1

11

4.2.

Snow analysis fields (anl_snwlev)

Codefigures0,

ParameterUnits

1, 17 Snow age

0,194,d5 Number of snow layers

Numeric

Snow albedo in the visible%
regionSnow albedo in the the near
0,194, 40%
infrared region0, 0, 0 TemperatureK
0,194, 39

0,1, 97 Mass density of snow

Liquid water content in
0,194, 16
snow0,194, 17 Ice content in snow

4.3.

4.4.

1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)114 (Snow level)kg m-3114 (Snow level)

kg m

-2

114 (Snow level)

kg m

-2

114 (Snow level)

Snow depth analysis fields (anl_snow)

Codefigures0,

Level

ParameterUnits

1, 11 Snow depth

Level
1 (Ground or water
surface)mIsobaric analysis fields (anl_p)

There are 45 isobaric surfaces (1,000, 975, 950, 925, 900, 875, 850, 825, 800, 775, 750, 700,
650, 600, 550, 500, 450, 400, 350, 300, 250, 225, 200, 175, 150, 125, 100, 85, 70, 60, 50, 40, 30,
20, 10, 7, 5, 3, 2, 1, 0.7, 0.3, 0.1, 0.03 and 0.01 hPa).
Codefigures
0,

0,

0,

0,

Parameter

Units
K

Filename0,1,

0 TemperatureDewpoint depression (or7deficit)0 Specific humidity

anl_p_tmp

0,

1,

1 Relative humidity

%

0,

2,

2 u-component of windm s-1

anl_p_ugrd-1

anl_p_vgrd
anl_p_strm

K

anl_p_depr

kg kg

2,

3 v-component of wind

m s

0,

2,

4 Stream function

m2 s-1

2,

5 Velocity potential

0,

Vertical velocity
2, 8(pressure)2, 12 Relative vorticity

0,
0,

0,

m

anl_p_spfh
anl_p_rh

0,
0,

-1

2

s

-1

anl_p_vpot-1

anl_p_vvel

Pa s
s-1

anl_p_relv

2, 13 Relative divergences-1

anl_p_reld

3,

gpm

anl_p_hgt

5 Geopotential height

Note: The saturated vapor pressure used to calculate dewpoint depression (or deficit) andrelative humidity from specific humidity is the value from over liquid water at a temperature of273.15K or higher, over ice at a temperature of 258.15K or lower, and the weighted average ofthe two with proportions linearly dependent on temperatures between 258.15 and 273.15K.

12

4.5.

Model level analysis fields (anl_mdl)

Codefigures
0,
0,

0,
1,

ParameterUnits

0 Temperature

Filename

K

0 Specific humidity

anl_mdl_tmp

kg kg

-1

anl_mdl_spfh-1

anl_mdl_ugrd

0,

2,

2 u-component of wind

m s

0,

2,

3 v-component of windm s-1

anl_mdl_vgrd

Vertical velocity
8(pressure)
5 Geopotential heightPa s-1

anl_mdl_vvel

gpm

anl_mdl_hgt

0,

2,

0,

3,

4.6.

Isentropic analysis fields (anl_isentrop)

There are 36 isentropic surfaces (270, 280, 290, 300, 310, 320, 330, 340, 350, 360, 370, 380,
390, 400, 425, 450, 475, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1,000, 1,250, 1,500,
1,750, 2,000, 2,500, 3,000, 3,500 and 4,000K).
Code
figuresParameter0,1,0 Specific humidity

0,

2,

2 u-component of wind

0,
0,

2,
2,

3 v-component of wind
6 Montgomery stream function

0,

Vertical velocity
2, 8(pressure)2, 14 Potential vorticity

0,

3,

0,

3,

0,

Units

anl_isentrop_spfh

m s

-1

anl_isentrop_ugrd

m s

-1

anl_isentrop_vgrd

2-2

anl_isentrop_mntsf-1

anl_isentrop_vvel

m

s

K m

5 Geopotential height
Square of Brunt-Vaisala
0,194, 38
frequency

4.7.

kg kg-1

Pa s

0 Pressure

Filename

2

kg

-1

s

-1

anl_isentrop_pvort

Pa

anl_isentrop_pres

gpm

anl_isentrop_hgt-2

anl_isentrop_bvf2sLand surface analysis fields (anl_land)

There are seven soil layers (2, 5, 12, 30, 50, 100 and 150 cm from the top).

13

Code
figures2,

ParameterUnits

3,192 Ground temperatureK

2,193,

1 Canopy temperatureK

2,193,

2

2,193,

3 Ice storage on canopy

2,193,

4

Liquid water storage on
groundcoverkg m

2,193,

5 Ice storage on groundcoverkg m-2Liquid water storage on
canopykg m-2kg m-2
-2

2,

0, 38

Soil volumetric ice content 3 -3m m(water equivalent)

2,

3, 10

Liquid volumetric soil
moisture (non-frozen)

2,3, 18 Soil temperature

m3 m-3

K

14

Level
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)106 (Depth below land
surface):106 (Depth
below land surface)
106 (Depth below land
surface):106 (Depth
below land surface)
106 (Depth below land
surface):106 (Depth
below land surface)4.8.

Two-dimensional instantaneous diagnostic fields (fcst_surf)Codefigures

Units

Parameter

0,

1, 64

Total column integrated
water vapour

kg m

-2

0,

1, 69

Total column integrated
cloud water

kg m

-2

0,

1, 70

Total column integrated
cloud ice

kg m

-2

0 Total ozone

DU0,1, 11 Snow depth

m

0,

1, 13

0,

2, 30 Frictional velocity

0,

3,0, 14,

Water equivalent ofaccumulated snow depth

kg m
m s

-2

-1

Pa

0 Pressure

0,194,

6 Energy stored in light snow J m-2

0,194,

7 Amount of light snow

kg m

-2

0,

6,

1 Total cloud cover

%

0,

6,

3 Low cloud cover

%

0,

6,

4 Medium cloud cover

%

0,

6,

5 High cloud cover

%

0,

3,

1 Pressure reduced to MSL

Pa

0,

0,

0 Temperature

K

0,

0,

7

0,

1,

0 Specific humidity

kg kg-1

0,

1,

1 Relative humidity

%

0,

2,

2 u-component of wind

m s

-1

0,

2,

3 v-component of wind

m s

-1

Dewpoint depression (ordeficit)K

Level
1 (Ground or water
surface): 8 (Nominal
top of the atmosphere)
1 (Ground or water
surface): 8 (Nominal
top of the atmosphere)
1 (Ground or water
surface): 8 (Nominal
top of the atmosphere)
1 (Ground or water
surface): 8 (Nominal
top of the atmosphere)
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)100 (Isobaric
surface):100 (Isobaric
surface)100 (Isobaric
surface):100 (Isobaric
surface)100 (Isobaric
surface):100 (Isobaric
surface)100 (Isobaric
surface):100 (Isobaric
surface)101 (Mean sea level)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground 2m)
103 (Specified heightlevel above ground10m)
103 (Specified heightlevel above ground10m)

Note: The saturated vapor pressure used to calculate dewpoint depression (or deficit) andrelative humidity from specific humidity is the value from over liquid water at a temperature of273.15K or higher, over ice at a temperature of 258.15K or lower, and the weighted average of15

the two with proportions linearly dependent on temperatures between 258.15 and 273.15K.
4.9.

Snow forecast fields (fcst_snwlev)

Codefigures0,

ParameterUnits

1, 17 Snow age

0,194,d5 Number of snow layers

Numeric

Snow albedo in the visible%
regionSnow albedo in the the near
0,194, 40%
infrared region0, 0, 0 TemperatureK
0,194, 39

0,1, 97 Mass density of snow

Liquid water content in
0,194, 16
snow0,194, 17 Ice content in snow

Level
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)114 (Snow level)

kg m

-3

114 (Snow level)

kg m

-2

114 (Snow level)

kg m

-2

114 (Snow level)

4.10. Isobaric forecast fields (fcst_p)
There are 45 isobaric surfaces (1,000, 975, 950, 925, 900, 875, 850, 825, 800, 775, 750, 700,
650, 600, 550, 500, 450, 400, 350, 300, 250, 225, 200, 175, 150, 125, 100, 85, 70, 60, 50, 40, 30,
20, 10, 7, 5, 3, 2, 1, 0.7, 0.3, 0.1, 0.03 and 0.01 hPa).
Codefigures
0,

0,

0,

0,

0,
0,

Parameter

UnitsK

fcst_p_tmp

K

fcst_p_depr

1,0 TemperatureDewpoint depression (or7deficit)0 Specific humidity

1,

1 Relative humidity

%

kg kg

fcst_p_ugrd
fcst_p_vgrd

2,

2 u-component of wind

m s

2,

3 v-component of wind

m s-1

2,

0,

2,

0,

4 Stream function-1

fcst_p_strm

m2 s-1

fcst_p_vpot-1

fcst_p_vvelm5 Velocity potential
Vertical velocity
2, 8(pressure)2, 12 Relative vorticity

fcst_p_spfh
fcst_p_rh

0,
0,

-1

-1

0,

0,

Filename

2

s

Pa s
s

-1

fcst_p_relv-1

fcst_p_reld
fcst_p_hgt

0,2, 13 Relative divergence

s

0,

3,

5 Geopotential height

gpm

0,

6,

7 Cloud amount%1 Ozone mixing ratio

kg kg

-1

fcst_p_o3mr

kg kg

-1

fcst_p_cwat

0, 14,

0,194, 41 Cloud water

fcst_p_cdca

Note: The saturated vapor pressure used to calculate dewpoint depression (or deficit) andrelative humidity from specific humidity is the value from over liquid water at a temperature of273.15K or higher, over ice at a temperature of 258.15K or lower, and the weighted average ofthe two with proportions linearly dependent on temperatures between 258.15 and 273.15K.

16

4.11. Model level forecast fields (fcst_mdl)
CodefiguresParameter

Units

0,

0,

0 Temperature

K

0,

1,

0 Specific humidity

kg kg

fcst_mdl_tmp

0,2,

2 u-component of wind

m s

-1

0,

2,

m s

-1

0,

2,

0,

3,

3 v-component of wind
Vertical velocity
8(pressure)
5 Geopotential height0,

6,

7 Cloud amount%0, 14,

1 Ozone mixing ratio
Cloud water content
0,194, 10 (including ice phase)
calculated by cloud scheme
Cloud water content
0,194, 11 (including ice phase) in
cumulus updraught region
Cloud cover calculated by
0,194, 36
cloud scheme
Cloud cover in cumulus
0,194, 37
updraught region
0,194, 41 Cloud water

Filename-1

fcst_mdl_spfh
fcst_mdl_ugrd
fcst_mdl_vgrd

Pa s-1

fcst_mdl_vvel

gpm

fcst_mdl_hgt
fcst_mdl_cdca

kg kg

-1

fcst_mdl_o3mr

kg kg-1

fcst_mdl_cwcls-1

fcst_mdl_cwccu

kg kg
%

fcst_mdl_cvrls%

fcst_mdl_cvrcu

kg kg

-1

fcst_mdl_cwat

4.12. Land surface forecast fields (fcst_land)
There are seven soil layers (2, 5, 12, 30, 50, 100 and 150 cm from the top).
CodefiguresParameter

Units

2,

0,

1 Surface roughnessm2,

3,192 Ground temperatureK

2,193,

1 Canopy temperatureK

2,193,

2

2,193,

3 Ice storage on canopy

2,193,

4

Liquid water storage on
groundcoverkg m-2

2,193,

5 Ice storage on groundcoverkg m-2Liquid water storage on
canopykg m-2kg m-22,

0, 38

Soil volumetric ice content 3 -3m m(water equivalent)

2,

3, 10

Liquid volumetric soil
moisture (non-frozen)

2,3, 18 Soil Temperature

m3 m-3

K

17

Level
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)106 (Depth below land
surface):106 (Depth
below land surface)
106 (Depth below land
surface):106 (Depth
below land surface)
106 (Depth below land
surface):106 (Depth
below land surface)4.13. Ocean surface boundary conditions (bnd_ocean)
There are four layers of sea ice (7, 14, 51 and 78 cm from the top).
CodefiguresParameter

Units

10,

2,

0 Ice cover

Proportion

10,

2,

8 Ice temperature

K

10,

3,

0 Water temperature

K

10,

2,

8 Ice temperature

K

Level
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)160 (Depth below sea
level):160 (Depth
below sea level)

Note: Water temperatures in sea ice areas are estimated from sea ice concentrations.

18

4.14. Two-dimensional average diagnostic fields (fcst_phy2m)
CodefiguresParameter

Units

Vertically integrated zonal
kg m-1 s-1
water vapour flux
Vertically integrated-1-1
0,194, 9 meridional water vapour
kg m sflux-20, 0, 10 Latent heat net flux
W m
0,194,

0,

8

W m

0,
0,

2, 17 Momentum flux, u-component

N m-2

0,

2, 18 Momentum flux, v-component

N m

0,

3,

0,
0,
0,

1 (Ground or water
surface): 8 (Nominal
top of the atmosphere)-20, 11 Sensible heat net flux
Convective precipitation
1, 37
rate
1, 52 Total precipitation rate
Total snowfall rate water
1, 53
equivalent
Large scale precipitation
1, 54
rate
1, 79 Evaporation rate

0,

Level

kg m

-2

s

-1

kg m-2 s-1
kg m

-2

s

-1

kg m-2 s-1
kg m-2 s-1-2

0 Pressure
Pa
Downward short-wave-20, 4, 7W m
radiation flux
Upward short-wave radiation
0, 4, 8W m-2
flux
Downward short-wave
0, 4, 52
W m-2
radiation flux, clear sky
Upward short-wave radiation
0, 4, 53
W m-2
flux, clear sky
Downward long-wave
0, 5, 3
W m-2
radiation flux
Upward long-wave radiation
0, 5, 4
W m-2
flux
Downward long-wave
0, 5, 8
W m-2
radiation flux, clear sky
Zonal momemtum flux by
0,194, 28
N m-2
short gravity wave
Meridional momemtum flux by
0,194, 29
N m-2
short gravity wave
Zonal momemtum flux by long
0,194, 30
N m-2
gravity wave
Meridional momemtum flux by-20,194, 31
N mlong gravity wave
Frequency of deep
0,194, 33%
convection
Frequency of shallow
0,194, 34%
convection
Frequency of stratocumulus
0,194, 35%
parameterisation
Downward short-wave-20, 4, 7W m
radiation flux
Upward short-wave radiation
0, 4, 8W m-2
flux
Upward short-wave radiation-20, 4, 53
W mflux, clear sky
Upward long-wave radiation
0, 5, 4
W m-2
flux
Net long-wave radiation
0, 5, 6
W m-2
flux, clear sky

19

1 (Ground or water
surface)

8 (Nominal top of
the atmosphere)4.15. Model level average diagnostic fields (fcst_phy3m)
CodefiguresParameter

Units

0,

Temperature tendency due to-1
K s
short-wave radiation
Temperature tendency due to
-1
0, 23
K s
long-wave radiation-2-1
3, 27 Updraught mass flux
kg m s0,6, 15 Cloud work function

0,
0,

0, 22

0,194,

1 Adiabatic heating rate

0,194,

2

0,194,

3

0,194,

J kg

4

Large scale condensation
heating rate
Convective heating rate
Vertical diffusion heating
rate
Adiabatic moistening rate-1

Filename
fcst_phy3m_ttswr
fcst_phy3m_ttlwr
fcst_phy3m_umflx
fcst_phy3m_cwork

K s

-1

fcst_phy3m_adhr

K s

-1

fcst_phy3m_lrghr

K s-1

fcst_phy3m_cnvhr-1

fcst_phy3m_vdfhr

K s

kg kg

-1

s

-1

fcst_phy3m_admr

0,194, 13 Large scale moistening rate kg kg

-1

s-1

fcst_phy3m_lrgmr

0,194, 14 Convective moistening rate-1

-1

fcst_phy3m_cnvmr

0,194, 12

0,194, 15
0,194, 18
0,194, 19
0,194, 20
0,194, 21
0,194, 22
0,194, 23
0,194, 24
0,194, 25
0,194, 26
0,194, 27
0,194, 32

kg kg

s

Vertical diffusion
-1
-1
kg kg
s
moistening rate
Adiabatic zonal
-1
-1
m s s
acceleration
Adiabatic meridionalm s-1 s-1
acceleration
Convective zonalm s-1 s-1
acceleration
Convective meridionalm s-1 s-1
acceleration
Vertical diffusion zonalm s-1 s-1
acceleration
Vertical diffusion
m s-1 s-1
meridional acceleration
Orographic gravity wave
m s-1 s-1
zonal acceleration
Orographic gravity wave
m s-1 s-1
meridional acceleration
Non-orographic gravity wave
m s-1 s-1
zonal acceleration
Non-orographic gravity wave
m s-1 s-1
meridional acceleration
Upward mass flux at cloud-2-1
kg m sbase

Note: Cloud work functions are output for layers 6 to 100.

20

fcst_phy3m_vdfmr
fcst_phy3m_aduafcst_phy3m_adva
fcst_phy3m_cnvua
fcst_phy3m_cnvva
fcst_phy3m_vdfua
fcst_phy3m_vdfva
fcst_phy3m_gwdoua
fcst_phy3m_gwdova
fcst_phy3m_gwdnua
fcst_phy3m_gwdnva
fcst_phy3m_mflxb

4.16. Land surface average diagnostic fields (fcst_phyland)CodefiguresParameterUnits2,193,

6 Interception loss

W m-2

2,193,

8 Transpiration

W m-2

2,193,

9 Water runoff

kg m-2 s-1

2,193,

9 Water runoff

kg m-2 s-1

Level
1 (Ground or water
surface)1 (Ground or water
surface)1 (Ground or water
surface)106 (Depth below land
surface 349cm)

4.17. Two-dimensional extreme fields (minmax_surf)CodefiguresParameter

Units

0,

0,

0 Temperature

K

0,

0,

0 Temperature

K

0,

2,

1 Wind speed

m s-1

5.

Invariant data

5.1.

Surface geopotential (TL479_surf)Codefigures
0,

5.2.

3,

Parameter

m2 s-2

4 Geopotential

103 (Specified heightlevel above ground2m), Maximum
103 (Specified heightlevel above ground2m), Minimum
103 (Specified heightlevel above ground2m), Maximum

Level
1 (Ground or water
surface)Land surface information (TL479_land)Codefigures
2,

Units

Level

0,

2,193,

Parameter
0

Units

Land cover (0 = sea, 1 =land)

Proportion
Code table
JMA4.12

7 Type of vegetation

21

Level
1 (Ground or water
surface)1 (Ground or water
surface)Type of vegetation

6.

Code
figure0 Sea or inland water

Meaning

1 Broadleaf-evergreen trees
2 Broadleaf-deciduous trees
3 Broadleaf and needleleaf trees
4 Needleleaf-evergreen trees
5 Needleleaf-deciduous trees
6 Broadleaf trees with groundcover
7 Groundcover
8 Broadleaf shrubs with groundcover
9 Broadleaf shrubs with bare soil
10 Dwarf trees and shrubs with groundcover (tundra)
11 No vegetation: bare soil
12 Broadleaf-deciduous trees with winter wheat
13 Perennial land ice

7.

Grid

7.1.

Quasi-regular Gaussian latitude/longitude grid

Model grid data are output to the quasi-regular Gaussian latitude/longitude grid. Latitudes ofthe model grid correspond to nodes for the 480-point Gauss-Legendre formula. The number ofgrid points along each parallel varies with latitude. The grid points in each parallel are evenly
spaced, with the first positioned at zero degrees longitude.

22#(±) Latitude

Weight#(±) Latitude

Weight1

8.97132438500418E+01

3.21410242214249E-05

Points48

51

7.09884635613671E+01

2.12985509693694E-03

432

2

8.93417749818453E+01

7.48168530349652E-05

6452

7.06138556554260E+01

2.17022524666533E-03448

38.89681123892152E+01

1.17552677581140E-0480

53

7.02392476810633E+01

2.21050262454479E-03

448

48.85939541406696E+01

1.60288965943286E-04

80

54

6.98646396421023E+01

2.25068550881293E-03480

58.82196078781340E+01

2.03019504350081E-04

96

55

6.94900315420870E+01

2.29077218175165E-03480

68.78451706351754E+01

2.45741694282220E-04

112

56

6.91154233843075E+01

2.33076092975026E-03480

78.74706825471415E+01

2.88453504772790E-04

112

57

6.87408151718218E+01

2.37065004338903E-03480

88.70961631892309E+01

3.31153040455306E-04

128

58

6.83662069074765E+01

2.41043781750629E-03480

98.67216232381897E+01

3.73838448031143E-04

128

59

6.79915985939242E+01

2.45012255126655E-03

512

10

8.63470690097088E+01

4.16507890057629E-04

144

60

6.76169902336403E+01

2.48970254824990E-03

512

11

8.59725044776891E+01

4.59159536182325E-04

160

61

6.72423818289372E+01

2.52917611650379E-03

512

12

8.55979322671010E+01

5.01791559744374E-04

160

62

6.68677733819776E+01

2.56854156862891E-03

512

13

8.52233541813702E+01

5.44402136391629E-04

192

63

6.64931648947864E+01

2.60779722185001E-03

512

14

8.48487715003565E+01

5.86989443464261E-04

192

64

6.61185563692617E+01

2.64694139808176E-03

512

15

8.44741851574452E+01

6.29551659737931E-04

192

65

6.57439478071844E+01

2.68597242400622E-03

560

16

8.40995958493309E+01

6.72086965314766E-04

192

66

6.53693392102271E+01

2.72488863114133E-03

560

17

8.37250041065544E+01

7.14593541599355E-04

224

67

6.49947305799622E+01

2.76368835591501E-03

560

18

8.33504103402387E+01

7.57069571336342E-04

224

68

6.46201219178694E+01

2.80236993973322E-03

560

19

8.29758148738921E+01

7.99513238630662E-04

224

69

6.42455132253426E+01

2.84093172905077E-03

560

20

8.26012179655640E+01

8.41922729003341E-04

224

70

6.38709045036956E+01

2.87937207544596E-03

560

21

8.22266198236011E+01

8.84296229491420E-04

224

71

6.34962957541681E+01

2.91768933568820E-03

560

22

8.18520206180633E+01

9.26631928657586E-04

240

72

6.31216869779308E+01

2.95588187180591E-03

560

23

8.14774204891306E+01

9.68928016727788E-04

240

73

6.27470781760901E+01

2.99394805116261E-03

576

24

8.11028195533889E+01

1.01118268560676E-03

256

74

6.23724693496925E+01

3.03188624652089E-03

576

25

8.07282179085931E+01

1.05339412898189E-03

256

75

6.19978604997286E+01

3.06969483611605E-03

640

26

8.03536156373213E+01

1.09556054240649E-03

288

76

6.16232516271367E+01

3.10737220372061E-03

640

27

7.99790128098096E+01

1.13768012335063E-03

288

77

6.12486427328063E+01

3.14491673872093E-03

640

28

7.96044094861749E+01

1.17975107129285E-03

288

78

6.08740338175814E+01

3.18232683617799E-03

640

29

7.92298057181738E+01

1.22177158779124E-03

288

79

6.04994248822629E+01

3.21960089690302E-03

640

30

7.88552015506067E+01

1.26373987656139E-03

320

80

6.01248159276119E+01

3.25673732751777E-03

640

31

7.84805970224489E+01

1.30565414356406E-03

320

81

5.97502069543518E+01

3.29373454053236E-03

640

32

7.81059921677671E+01

1.34751259705083E-03

320

82

5.93755979631705E+01

3.33059095440539E-03

640

33

7.77313870164688E+01

1.38931344767484E-03

320

83

5.90009889547231E+01

3.36730499361463E-03

640

34

7.73567815949179E+01

1.43105490855114E-03

320

84

5.86263799296331E+01

3.40387508872392E-03

640

35

7.69821759264451E+01

1.47273519532604E-03

336

85

5.82517708884949E+01

3.44029967645024E-03

640

36

7.66075700317710E+01

1.51435252626641E-03

336

86

5.78771618318753E+01

3.47657719973200E-03

640

37

7.62329639293619E+01

1.55590512233218E-03

384

87

5.75025527603147E+01

3.51270610779207E-03

672

38

7.58583576357279E+01

1.59739120725222E-03

384

88

5.71279436743294E+01

3.54868485620887E-03

672

39

7.54837511656755E+01

1.63880900758957E-03

384

89

5.67533345744123E+01

3.58451190697808E-03

672

40

7.51091445325215E+01

1.68015675283836E-03

384

90

5.63787254610342E+01

3.62018572858026E-03

672

41

7.47345377482760E+01

1.72143267547679E-03

384

91

5.60041163346457E+01

3.65570479604538E-03

672

42

7.43599308237989E+01

1.76263501106250E-03

384

92

5.56295071956773E+01

3.69106759102067E-03

672

43

7.39853237689341E+01

1.80376199829416E-03

384

93

5.52548980445416E+01

3.72627260183205E-03

720

44

7.36107165926257E+01

1.84481187909088E-03

400

94

5.48802888816331E+01

3.76131832355118E-03

720

45

7.32361093030190E+01

1.88578289867238E-03

400

95

5.45056797073301E+01

3.79620325805875E-03

720

46

7.28615019075468E+01

1.92667330562609E-03

400

96

5.41310705219951E+01

3.83092591410952E-03

720

47

7.24868944130067E+01

1.96748135198268E-03

432

97

5.37564613259756E+01

3.86548480739258E-03

720

48

7.21122868256266E+01

2.00820529329963E-03

432

98

5.33818521196051E+01

3.89987846060002E-03

720

49

7.17376791511238E+01

2.04884338872800E-03

432

99

5.30072429032034E+01

3.93410540348704E-03

720

50

7.13630713947562E+01

2.08939390108519E-03

432 100

5.26326336770780E+01

3.96816417293494E-03

720

23

Points#(±) Latitude

Weight(±) Latitude

Weight101

5.22580244415239E+01

4.00205331301507E-03

Points

720 151#3.35275548889748E+01

5.45035031536657E-03

960

102

5.18834151968246E+01

4.03577137504670E-03

720 152

3.31529453980947E+01

5.47384484114538E-03

960

103

5.15088059432529E+01

4.06931691766726E-03

768 153

3.27783359047431E+01

5.49710537336844E-03

960

104

5.11341966810710E+01

4.10268850688452E-03

768 1543.24037264089755E+01

5.52013091770407E-03

960

105

5.07595874105310E+01

4.13588471614579E-03

768 155

3.20291169108464E+01

5.54292048986674E-03

960

106

5.03849781318759E+01

4.16890412639242E-03

768 156

3.16545074104089E+01

5.56547311565769E-03

960

107

5.00103688453394E+01

4.20174532612504E-03

768 157

3.12798979077147E+01

5.58778783100679E-03

960

108

4.96357595511468E+01

4.23440691146334E-03

768 158

3.09052884028147E+01

5.60986368201383E-03

960

109

4.92611502495150E+01

4.26688748620272E-03

768 159

3.05306788957580E+01

5.63169972499084E-03

960

110

4.88865409406531E+01

4.29918566187846E-03

768 160

3.01560693865932E+01

5.65329502649918E-03

960

111

4.85119316247629E+01

4.33130005782172E-03

768 161

2.97814598753674E+01

5.67464866339300E-03

960

112

4.81373223020389E+01

4.36322930122074E-03

768 1622.94068503621267E+01

5.69575972285562E-03

960

113

4.77627129726689E+01

4.39497202717709E-03

768 1632.90322408469164E+01

5.71662730244088E-03

960

114

4.73881036368341E+01

4.42652687876680E-03

784 1642.86576313297804E+01

5.73725051011027E-03

960

115

4.70134942947093E+01

4.45789250709639E-03

784 165

2.82830218107621E+01

5.75762846427216E-03

960

116

4.66388849464637E+01

4.48906757136242E-03

784 166

2.79084122899035E+01

5.77776029381823E-03

960

117

4.62642755922606E+01

4.52005073890645E-03

800 1672.75338027672462E+01

5.79764513816189E-03

960

118

4.58896662322577E+01

4.55084068527233E-03

800 168

2.71591932428305E+01

5.81728214727436E-03

960

119

4.55150568666077E+01

4.58143609426543E-03

800 1692.67845837166960E+01

5.83667048172128E-03

960

120

4.51404474954582E+01

4.61183565800675E-03

800 170

2.64099741888815E+01

5.85580931269844E-03

960

121

4.47658381189519E+01

4.64203807698904E-03

864 171

2.60353646594251E+01

5.87469782206754E-03

960

122

4.43912287372271E+01

4.67204206013104E-03

864 172

2.56607551283640E+01

5.89333520239051E-03

960

123

4.40166193504173E+01

4.70184632483686E-03

864 173

2.52861455957346E+01

5.91172065696470E-03

960

124

4.36420099586523E+01

4.73144959704636E-03

864 174

2.49115360615727E+01

5.92985339985663E-03

960

125

4.32674005620574E+01

4.76085061129029E-03

864 175

2.45369265259134E+01

5.94773265593588E-03

960

126

4.28927911607541E+01

4.79004811074912E-03

864 176

2.41623169887911E+01

5.96535766090749E-03

960

127

4.25181817548603E+01

4.81904084729846E-03

864 177

2.37877074502395E+01

5.98272766134532E-03

960

128

4.21435723444901E+01

4.84782758157077E-03

864 178

2.34130979102916E+01

5.99984191472422E-03

960

129

4.17689629297543E+01

4.87640708300262E-03

864 1792.30384883689801E+01

6.01669968945148E-03

960

130

4.13943535107601E+01

4.90477812989028E-03

864 180

2.26638788263366E+01

6.03330026489821E-03

960

131

4.10197440876120E+01

4.93293950943950E-03

864 1812.22892692823927E+01

6.04964293143004E-03

960

132

4.06451346604108E+01

4.96089001782110E-03

864 182

2.19146597371789E+01

6.06572699043786E-03

960

133

4.02705252292549E+01

4.98862846021772E-03

864 183

2.15400501907255E+01

6.08155175436728E-03

960

134

3.98959157942395E+01

5.01615365087918E-03

864 184

2.11654406430621E+01

6.09711654674803E-03

960

135

3.95213063554571E+01

5.04346441317004E-03

864 1852.07908310942179E+01

6.11242070222305E-03

960

136

3.91466969129978E+01

5.07055957962133E-03

864 186

2.04162215442216E+01

6.12746356657708E-03

960

137

3.87720874669489E+01

5.09743799198135E-03

864 187

2.00416119931013E+01

6.14224449676414E-03

960

138

3.83974780173953E+01

5.12409850126306E-03

864 188

1.96670024408849E+01

6.15676286093547E-03

960

139

3.80228685644196E+01

5.15053996779421E-03

896 189

1.92923928875994E+01

6.17101803846612E-03

960

140

3.76482591081022E+01

5.17676126126671E-03

896 190

1.89177833332718E+01

6.18500941998216E-03

960

141

3.72736496485211E+01

5.20276126078377E-03

896 191

1.85431737779285E+01

6.19873640738595E-03

960

142

3.68990401857523E+01

5.22853885490888E-03

896 192

1.81685642215955E+01

6.21219841388209E-03

960

143

3.65244307198698E+01

5.25409294171275E-03

896 193

1.77939546642984E+01

6.22539486400268E-03

960

144

3.61498212509456E+01

5.27942242882011E-03

896 194

1.74193451060624E+01

6.23832519363142E-03

960

145

3.57752117790499E+01

5.30452623345651E-03

896 195

1.70447355469123E+01

6.25098885002834E-03

960

146

3.54006023042508E+01

5.32940328249612E-03

896 196

1.66701259868728E+01

6.26338529185266E-03

960

147

3.50259928266149E+01

5.35405251250476E-03

896 197

1.62955164259678E+01

6.27551398918686E-03

960

148

3.46513833462070E+01

5.37847286978859E-03

896 198

1.59209068642213E+01

6.28737442355860E-03

960

149

3.42767738630902E+01

5.40266331043639E-03

960 199

1.55462973016567E+01

6.29896608796315E-03

960

150

3.39021643773261E+01

5.42662280036560E-03

960 200

1.51716877382971E+01

6.31028848688494E-03

960

24

Points#(±) Latitude

Weight201

1.47970781741655E+01

6.32134113631905E-03

Points960

202

1.44224686092845E+01

6.33212356379152E-03

960

203

1.40478590436763E+01

6.34263530837986E-03

960

204

1.36732494773629E+01

6.35287592073251E-03

960

205

1.32986399103661E+01

6.36284496308818E-03

960

206

1.29240303427074E+01

6.37254200929467E-03

960

207

1.25494207744081E+01

6.38196664482667E-03

960

208

1.21748112054892E+01

6.39111846680401E-03

960

209

1.18002016359714E+01

6.39999708400857E-03

960

210

1.14255920658754E+01

6.40860211690103E-03

960

211

1.10509824952215E+01

6.41693319763720E-03

960

212

1.06763729240299E+01

6.42498997008357E-03

960

213

1.03017633523204E+01

6.43277208983275E-03

960

214

9.92715378011306E+00

6.44027922421807E-03

960

215

9.55254420742729E+00

6.44751105232771E-03

960

216

9.17793463428255E+00

6.45446726501867E-03

960

217

8.80332506069813E+00

6.46114756492975E-03

960

218

8.42871548669312E+00

6.46755166649441E-03

960

219

8.05410591228649E+00

6.47367929595282E-03

960

220

7.67949633749707E+00

6.47953019136379E-03

960

221

7.30488676234353E+00

6.48510410261572E-03

960

222

6.93027718684441E+00

6.49040079143745E-03

960

223

6.55566761101815E+00

6.49542003140845E-03

960

224

6.18105803488311E+00

6.50016160796837E-03

960

225

5.80644845845747E+00

6.50462531842642E-03

960

226

5.43183888175933E+00

6.50881097196976E-03

960

227

5.05722930480673E+00

6.51271838967181E-03

960

228

4.68261972761759E+00

6.51634740450019E-03

960

229

4.30801015020975E+00

6.51969786132319E-03

960

230

3.93340057260100E+00

6.52276961691697E-03

960

231

3.55879099480902E+00

6.52556253997142E-03

960

232

3.18418141685146E+00

6.52807651109588E-03

960

233

2.80957183874591E+00

6.53031142282417E-03

960

234

2.43496226050988E+00

6.53226717961927E-03

960

235

2.06035268216087E+00

6.53394369787738E-03

960

236

1.68574310371632E+00

6.53534090593138E-03

960

237

1.31113352519365E+00

6.53645874405396E-03

960

238

9.36523946610251E-01

6.53729716446036E-03

960

239

5.61914367983491E-01

6.53785613131012E-03

960

240

1.87304789330710E-01

6.53813562070873E-03

960

8.

Vertical coordinates

8.1.

Model level (Hybrid level)

Model fields are produced for 100 hybrids defined with half-levels 𝑝𝑘+1 as boundaries:
2

𝑝

𝑘+

1 = 𝐴 1 + 𝐵 1 𝑝𝑠
𝑘+
𝑘+
2
2
2

Here, ps is surface pressure. Coefficients A and B are given in the tables below for k = 0, 1, 2,…, 100. The following equation by Simmons and Burridge (1981) gives full levels, with pressures
representing each hybrid level except the uppermost one (k = 100):
𝑝𝑘 = 𝑒𝑥𝑝 [1(𝑝 1 𝑙𝑛 𝑝 1 − 𝑝 1 𝑙𝑛 𝑝 1 ) − 𝐶]𝑘−𝑘+𝑘+
𝛥𝑝𝑘 𝑘−222225Here, C = 1 and k = 1, 2, …, 99. The full-level pressure for the uppermost one (k = 100) is
given by1

𝑝100 = 2 𝑝99.5 .
Half level

Full level

A （Pa）B

p （Pa）

0.00000000000000E+00

1.00000000000000E+00

1.00000000000000E+05

0.5 100000.00

3.81960202384420E-01

9.98082302745425E-01

9.98086122347449E+04

1.5

99904.29

1

2.28291058268584E+00

9.95295154130078E-01

9.95317983235905E+04

2.599670.172

7.26302991079037E+00

9.91568913909771E-01

9.91641544208879E+04

3.5

99347.92

3

1.75014084835484E+01

9.86835732357729E-01

9.87010746442564E+04

4.5

98932.52

4

3.58377859542454E+01

9.81029007209412E-01

9.81387385068954E+04

5.5

98419.77

5

6.57885280451939E+01

9.74083114967637E-01

9.74741000248089E+04

6.5

97806.23

6

1.11534392415342E+02

9.65933434381879E-01

9.67048778306032E+04

7.5

97089.23

7

1.77878399880398E+02

9.56516672775122E-01

9.58295456773926E+04

8.5

96266.8882.70172962859622E+02

9.45771497843382E-01

9.48473227471978E+04

9.5

95338.01

9

3.94216325080919E+02

9.33639468704960E-01

9.37581631955769E+04

10.5

94302.22

10

5.56119328049108E+02

9.20066250467165E-01

9.25627443747656E+04

11.5

93159.81

11

7.62144528509427E+02

9.05003086586742E-01

9.12624531871836E+04

12.5

91911.83

12

1.01852072917784E+03

8.88408493057623E-01

8.98593700349401E+04

13.5

90560.0113

1.33123702783589E+03

8.70250128253278E-01

8.83562498531637E+04

14.5

89106.75

141.70582150607621E+03

8.50506782429516E-01

8.67564997490278E+04

15.587555.16

15

2.14711063050055E+03

8.29170421862139E-01

8.50641528167144E+04

16.5

85908.94

16

2.65901628229974E+03

8.06248214805148E-01

8.32838377628145E+04

17.5

84172.43

17

3.24429801819574E+03

7.81764460391533E-01

8.14207440573490E+04

18.582350.53

18

3.90434864741328E+03

7.55762337748587E-01

7.94805824222720E+04

19.5

80448.71

19

4.63900143785868E+03

7.28305391427328E-01

7.74695405805915E+04

20.5

78472.91

20

5.44636719722841E+03

6.99478671154904E-01

7.53942343127188E+04

21.5

76429.54

21

6.32270907737545E+03

6.69389449218261E-01

7.32616539992015E+04

22.5

74325.39

22

7.26236220165995E+03

6.38167447649298E-01

7.10791069665898E+04

23.5

72167.63

23

8.25770411003936E+03

6.05964519813420E-01

6.88541560913814E+04

24.5

69963.68

24

9.29918056913880E+03

5.72953746816960E-01

6.65945552508348E+04

25.5

67721.21

25

1.03753895390152E+04

5.39327927948553E-01

6.43081823338705E+04

26.5

65448.04

26

1.14732240805217E+04

5.05297465547429E-01

6.20029706352646E+04

27.5

63152.07

27

1.25780728029053E+04

4.71087667442663E-01

5.96868395471716E+04

28.5

60841.23

28

1.36740741837049E+04

4.36935513458310E-01

5.73676255295359E+04

29.5

58523.40

29

1.47444188483625E+04

4.03085955334218E-01

5.50530143817843E+04

30.5

56206.35

30

1.57716917886268E+04

3.69787840612997E-01

5.27504758499265E+04

31.5

53897.65

31

1.67382446406603E+04

3.37289569438974E-01

5.04672015845577E+04

32.5

51604.63

32

1.76265866424519E+04

3.05834607737402E-01

4.82100474161921E+04

33.5

49334.32

33#

p （Pa）

Note: Half- and full-level pressure values are for a ground pressure ps of 1,000 hPa.

26#
SurfaceHalf level

Full level

A （Pa）B

p （Pa）#

p （Pa）

1.84197818378429E+04

2.75656989982275E-01

4.59854808360704E+04

34.5

47093.39

34

1.91018395617755E+04

2.46976949037224E-01

4.37995344654979E+04

35.5

44888.0735

1.96580852716381E+04

2.19996808968090E-01

4.16577661684471E+04

36.5

42724.18

36

2.00755268600696E+04

1.94896994550394E-01

3.95652263151090E+04

37.540607.00

37

2.03482038553370E+04

1.71782286882544E-01

3.75264325435914E+04

38.5

38541.34

38

2.04828643482145E+04

1.50624878505730E-01

3.55453521987874E+04

39.5

36531.42

39

2.04887651769179E+04

1.31366272806837E-01

3.36253924576016E+04

40.534580.93

40

2.03759691160234E+04

1.13934288680911E-01

3.17693979841145E+04

41.5

32693.00

41

2.01551248032749E+04

9.82453099923661E-02

2.99796558025115E+04

42.5

30870.20

42

1.98372514257646E+04

8.42065550889962E-02

2.82579069346642E+04

43.5

29114.54

43

1.94335331685911E+04

7.17183105876630E-02

2.66053642273574E+04

44.5

27427.49

44

1.89551277648791E+04

6.06760792963919E-02

2.50227356945183E+04

45.5

25810.01

45

1.84129927154439E+04

5.09725990918127E-02

2.35102526246252E+04

46.5

24262.57

46

1.78177319103491E+04

4.24996974349424E-02

2.20677016538433E+04

47.5

22785.1747

1.71794645241548E+04

3.51499545721629E-02

2.06944599813711E+04

48.5

21377.4148

1.65077172105776E+04

2.88181569343803E-02

1.93895329040156E+04

49.5

20038.46

49

1.58113398251101E+04

2.34025304520536E-02

1.81515928703155E+04

50.5

18767.1650

1.50984441846141E+04

1.88057511341314E-02

1.69790192980272E+04

51.5

17562.0451

1.43763647529064E+04

1.49357370648969E-02

1.58699384593961E+04

52.5

16421.36

52

1.36516396355225E+04

1.17062317737897E-02

1.48222628129015E+04

53.5

15343.1253

1.29300098824532E+04

9.03719362012052E-03

1.38337292444653E+04

54.5

14325.15

54

1.22164348352140E+04

6.85500936597729E-03

1.29019357718117E+04

55.5

13365.13

55

1.15151211086030E+04

5.09255250661131E-03

1.20243763592641E+04

56.5

12460.58

56

1.08295627574817E+04

3.68910825996248E-03

1.11984735834779E+04

57.5

11608.98

57

1.01625902306937E+04

2.59018749799379E-03

1.04216089804931E+04

58.5

10807.71

58

9.51642584110599E+03

1.74725147298966E-03

9.69115098840496E+03

59.5

10054.17

59

8.89274366467120E+03

1.11736810979251E-03

9.00448047565045E+03

60.5

9345.7160

8.29273200395698E+03

6.62819064436207E-04

8.35901391040060E+03

61.5

8679.7561

7.71715679490758E+03

3.50674852621987E-04

7.75222428016978E+03

62.5

8053.7162

7.16642458295615E+03

1.52353280156357E-04

7.18165991097179E+03

63.5

7465.1263

6.64064393089613E+03

4.31742990920429E-05

6.64496136080533E+03

64.5

6911.5764

6.13968433295405E+03

1.92238660659313E-06

6.13987657161471E+03

65.5

6390.76655.66427445587516E+03

0.00000000000000E+00

5.66427445587516E+03

66.5

5900.48

66

Note: Half- and full-level pressure values are for a ground pressure ps of 1,000 hPa.

27#

Half level

Full level

A （Pa）B

p （Pa）#

p （Pa）

5.21615706738968E+03

0.00000000000000E+00

5.21615706738968E+03

67.5

5438.6867

4.79367045972906E+03

0.00000000000000E+00

4.79367045972906E+03

68.5

5003.4368

4.39511426936575E+03

0.00000000000000E+00

4.39511426936575E+03

69.5

4592.95

69

4.01894997405415E+03

0.00000000000000E+00

4.01894997405415E+03

70.5

4205.6370

3.66380767175041E+03

0.00000000000000E+00

3.66380767175041E+03

71.5

3840.0171

3.32849110461126E+03

0.00000000000000E+00

3.32849110461126E+03

72.5

3494.8172

3.01198052234190E+03

0.00000000000000E+00

3.01198052234190E+03

73.5

3168.9273

2.71343284894173E+03

0.00000000000000E+00

2.71343284894173E+03

74.5

2861.4174

2.43217850068518E+03

0.00000000000000E+00

2.43217850068518E+03

75.5

2571.5275

2.16771411986701E+03

0.00000000000000E+00

2.16771411986701E+03

76.5

2298.6876

1.91969046221818E+03

0.00000000000000E+00

1.91969046221818E+03

77.5

2042.4577

1.68789473358617E+03

0.00000000000000E+00

1.68789473358617E+03

78.5

1802.5578

1.47222684248365E+03

0.00000000000000E+00

1.47222684248365E+03

79.5

1578.8379

1.27266934551692E+03

0.00000000000000E+00

1.27266934551692E+03

80.5

1371.2480

1.08925132929818E+03

0.00000000000000E+00

1.08925132929818E+03

81.5

1179.7781

9.22007094507183E+02

0.00000000000000E+00

9.22007094507183E+02

82.5

1004.4782

7.70931257919773E+02

0.00000000000000E+00

7.70931257919773E+02

83.5

845.3483

6.35932704095892E+02

0.00000000000000E+00

6.35932704095892E+02

84.5

702.3584

5.16790597980399E+02

0.00000000000000E+00

5.16790597980399E+02

85.5

575.3385

4.13116273736552E+02

0.00000000000000E+00

4.13116273736552E+02

86.5

463.9986

3.24325080743702E+02

0.00000000000000E+00

3.24325080743702E+02

87.5

367.8387

2.49622034667881E+02

0.00000000000000E+00

2.49622034667881E+02

88.5

286.16881.88004271574096E+02

0.00000000000000E+00

1.88004271574096E+02

89.5

218.0989

1.38281806013940E+02

0.00000000000000E+00

1.38281806013940E+02

90.5

162.5190

9.91160499134695E+01

0.00000000000000E+00

9.91160499134695E+01

91.5

118.1691

6.90732101617709E+01

0.00000000000000E+00

6.90732101617709E+01

92.5

83.64

92

4.66874387295308E+01

0.00000000000000E+00

4.66874387295308E+01

93.5

57.52

93

3.05269244112852E+01

0.00000000000000E+00

3.05269244112852E+01

94.5

38.32

94

1.92554217446999E+01

0.00000000000000E+00

1.92554217446999E+01

95.5

24.68

95

1.16822796663948E+01

0.00000000000000E+00

1.16822796663948E+01

96.5

15.31

96

6.79585510522008E+00

0.00000000000000E+00

6.79585510522008E+00

97.5

9.13

97

3.77794973185743E+00

0.00000000000000E+00

3.77794973185743E+00

98.5

5.21

98

2.00000000000000E+00

0.00000000000000E+00

2.00000000000000E+00

99.5

2.84

99

0.00000000000000E+00

0.00000000000000E+00

0.00000000000000E+00 100.5

1.00

100

#

Note: Half- and full-level pressure values are for a ground pressure ps of 1,000 hPa.

9.

Physical constants
Quantity

Value
-8

W m

6

m

Stefan-Boltzmann constant σ

5.67 x 10

Earth's radius

6.371 x 10

Angular speed of Earth's rotation

7.29245 x 10-5-29.80665 m s

Gas constant for dry air

287.04 J K-1 kg-1

Specific heat of dry air at constant pressure c p1004.6 J K-1 kg-1

Latent heat of vaporization

2.507 x 10

Solar constant1365 W m

28

-2

-4

rad s

-2

Gravitational acceleration

6

K

J kg

-1

-1

10. Climatological normals
Climatological normals have been calculated for the period from 1991 to 2020 using themethods described below.
10.1. Daily mean smooth climatological normals
This calculation involves two steps. In the first, daily values are computed using six-hourly
values for analysis and instantaneous forecast fields and averages from the beginning of forecasts
up to six hours for average diagnostic fields, and a simple average is then taken for the base period
for each day of the year except leap days. In the second, Lanzcos low-pass filtering (Duchon1979) with 121-term weight factors and a 60-day cutoff is applied to the time sequence of daily
values to treat the high-frequency variation remaining in the daily values calculated in the firststep. Climatological normals for leap days are derived by averaging the smooth climatologicalnormals for 28th February and 1st March.
The concept of this method is quite simple. It should be noted that monthly means calculated
from daily means do not coincide with those outlined above due to the difference in treatment forleap days and with the presence or absence of filtering.
10.2. Monthly mean climatological normals
Monthly mean climatological normals are calculated by simply averaging historical monthly
mean values.

References
Duchon, C. E., 1979: Lanczos filtering in one and two dimensions. J. Appl. Meteor., 18, 1016–
1022, doi:10.1175/1520-0450(1979)018<1016:LFIOAT>2.0.CO;2.
Kobayashi, S., Y. Kosaka, J. Chiba, T. Tokuhiro, Y. Harada, C. Kobayashi, and H. Naoe, 2021:
JRA-3Q: Japanese Reanalysis for Three Quarters of a Century. Joint WCRP-WWRP Symposium
on Data Assimilation and Reanalysis/ECMWF Annual Seminar 2021, online, 13-17 September
2021, O4-2, https://symp-bonn2021.sciencesconf.org/data/355900.pdf.
Simmons, A. J., and D. M. Burridge., 1981: An energy and angular-momentum conserving
vertical finite-difference scheme and hybrid vertical coordinates. Mon. Wea. Rev., 109, 758766, doi:10.1175/1520-0493(1981)109<0758:AEAAMC>2.0.CO;2.
WMO, 2022: Manual on Codes I.2. World Meteorological Organization, Geneva, Switzerland,29