Product: Effective Hydrologic Angular Momentum Functions (HAM)
Effective Hydrological Angular Momentum Functions (HAM) 1977 - ESMGFZ HAM v1.2 24h - Version metadata

Available downloads

Title

Effective Hydrological Angular Momentum Functions (HAM) 1977 - ESMGFZ HAM v1.2 24h
Number

1977
Volume

ESMGFZ HAM v1.2 24h
Date

2022-10-21
Content

effective angular momentum functions from hydrological (land) mass and motion terms
File units : dimensionless earth rotation excitation functions
Issue date : 2017-04-20
Version number : v1.2

Number of data records : 365
Subtracted mean value : mean from 2003-01-01 to 2014-12-31 (only x-, y-, z-component mass terms)
-1.722266235718563e-07 1.442803309340720e-06 2.052039186123164e-08

Hydrological model : Land Surface Discharge Model (LSDM)
Horizontal domain : global, continental land surface
Horizontal resolution : 0.5 x 0.5 degree (regular grid)
Vertical resolution : 1 surface layer

Hydrologic model forcing :
Precipitation : daily sum from 3h ECMWF operational model (short-term forecasts)
Evaporation : daily sum from 3h ECMWF operational model (short-term forecasts)
Temperature : daily average from 6h ECMWF operational model (analyses)

Data assimilated : None

Notes : These HAMs are part of a set of consistently processed Earth rotation excitation
function (AAM, OAM, HAM). The ocean model MPIOM and the hydrological model LSDM were
forced consistently with operational analysis data from the ECMWF.

Further references to be mentioned, when LSDM data are used:
Dill, R., Hydrological model LSDM for operational Earth rotation and gravity field variations.
GFZ Scientific Technical Report STR08/09, 2008

Documentation

GFZ provides these data as Associated Product Centre by order of the International Earth Rotation and Reference System Service (IERS). The data is public availably without any warranty of any kind what so ever, either express or implied, including warranties of merchantability. GFZ shall not be liable for incidental, consequential, or special consequences arising out of the use of this data.

operational_AAM/
ESMGFZ_AAM_v1.0_03h_yyyy.asc daily updated yearly AAM file
1976-01-01 until now

operational_OAM/
ESMGFZ_OAM_v1.0_03h_yyyy.asc daily updated yearly OAM file
1976-01-01 until now

operational_HAM/
ESMGFZ_HAM_v1.2_24h_yyyy.asc daily updated yearly HAM file
1976-01-01 until now

-----------------------------------------------------------------------------------------

Data Description:

Data are values of effective angular momentum functions (EAM) of the atmosphere, the ocean, and land hydrology as calculated from 6-hourly ECMWF (European Centre for Medium-range Weather Forecasts) operational atmospheric forcing data by means of theMax Planck Institute Ocean Model (MPIOM) and the Land Surface Discharge Model(LSDM). All the data is processed consistently to the GRACE de-aliasing products AOD1BRelease 06. Model description and citation info is given in the references at the end of this file.

ftp://ig2-dmz.gfz-potsdam.de/EAM/README
Time Interval

24h
Time Start

1977-01-01 12:00:00
Time End

1977-12-31 12:00:00
Data Points

365
Data

YYYY MM DD HH MJD mass term(x,y,z) motion term(x,y,z)
Format Description

%4s %2s %2s %2s %8s %23.15e %23.15e %23.15e %23.15e %23.15e %23.15e \n
Format

ASCII
Frequency

daily
Keywords

geophysical fluids, models
Reference

Dobslaw, H., R. Dill, A. Groetzsch, A. Brzezinski, and M. Thomas (2010),
Seasonal polar motion excitation from numerical models of atmosphere, ocean,
and continental hydrosphere, J. Geophys. Res., doi:10.1029/2009JB007127

Created by

Deutsches GeoForschungsZentrum GFZ
Dep. 1: Geodesy and Remote Sensing
Sec. 1.3: Earth System Modelling
Contact

dobslaw@gfz-potsdam.de
Distribution

onLine
Source

ftp://esmdata.gfz-potsdam.de/EAM/operational_HAM/