GLIMS: Global Land Ice Measurements from Space

Monitoring the World's Changing Glaciers

GLIMS Database Data Dictionary

Date: 2002-05-17

Note: P - primary key, F - foreign key.

See previous versions of the data dictionary.

Glacier_Static
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
glacier_id	varchar(20)	P	X	unique Glacier ID number, generated from lon/lat of glacier
glacier_name	varchar(40)		X	Glacier name, if there is one.
wgms_id	varchar(14)			World Glacier Monitoring Service (WGMS) ID, if assigned
local_glacier_id	varchar(20)		X	Glacier ID used by RCs.
parent_icemass_id	varchar(20)			Reference for parent glacier ID
glacier_loc_lon	numeric(9,6)		X	Longitude
glacier_loc_lat	numeric(9,6)		X	Latitude
primary_classification	smallint			Classification of glaciers, currently 10 valids from WGI
form	smallint			Form of glaciers, currently 10 valids from WGI
frontal_characteristics	smallint			Enumerated field, 6 valids from WGI
longitudinal_characteristics	smallint			Enumerated field, 6 valids from WGI
dominant_mass_source	smallint			Enumerated field, 4 valids from WGI
tongue_activity	smallint			Enumerated field, 9 valids from WGI

Glacier_Dynamic
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
analysis_id	int	P	X	ID for this analysis (snapshot)
glacier_id	varchar(20)	F	X	Glacier ID number, from Glacier_Static table
data_source	varchar(255)		X	Desc. of data source, e.g. ASTER image, GPS survey, etc. (TEXT)
analysis_timestamp	datetime		X	Time stamp for this analysis (date and time)
institution_id	int	F	X	ID of institution where the analysis was done, from Institution table
analyst_given_name	varchar(50)		X	First name of the person in charge of the analysis
analyst_surname	varchar(50)		X	Last name of the person in charge of the analysis
process_desc	varchar(200)		X	Description of the processing (including algorithms) used in the analysis
three_d_desc	varchar(200)			Description of how 3-D information was derived
width	float			Representative width of glacier, meters
length	float			Representative length of glacier, meters
area	float			Representative total area of glacier, km2
abzone_area	float			Area of ablation zone of glacier, km2
speed	float			Representative speed (float, m/a)
ela	float			ELA value
record_status	varchar(20)			Status of this database record.(ok,bad, etc.)

Glacier_Line
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
analysis_id	int	P/F	X	from Glacier_Dynamic table
segment_id	int	P/F	X	from Segment table
segment_order	int		X	Serial number for the segment on glacier outline
line_type	varchar(20)			Type of glacier lines, may be from valids

Segment
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
segment_id	int	P	X	unique segment ID number
segment_type	varchar(30)		X	measured,arbitrary
segment_label	varchar(32)			cloud,terminus,divide,etc
segment_left_material	char(3)			Materials on left side: glacier,nonglacier,ice,rock,snow,vegetation,water
segment_right_material	char(3)			Materials on right side: glacier,nonglacier,ice,rock,snow,vegetation,water
orthocorrected	char(1)		X	Flag to indicate whether location is terrain-corrected or not
loc_unc_x	float			Local uncertainty of x
loc_unc_y	float			Local uncertainty of y
glob_unc_x	float			Global uncertainty of x
glob_unc_y	float			Global uncertainty of y
seg_left_feature	char(3)			selection from valids: glacier, lake, etc
seg_right_feature	char(3)			selection from valids: glacier, lake, etc

Segment_Point
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
segment_point_id	int	P	X	unique segment point ID number
segment_id	int	F		segment ID number, from Segment table
pnt_x_coord	float		X	x-coordinate of segment point
pnt_y_coord	float		X	y-coordinate of segment point
pnt_z_coord	float			z-coordinate (geoidal) elevation of segment point

Tiepoint_Region
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
tiepoint_region_id	int	P	X	ID of tiepoint region (primary key).
institution_id	int	F
tiepoint_region_timestamp	datetime			Time/Date the tiepoint polygon was created
comment	varchar(255)			Text field for additional comments

Tiepoint_Region_Outline
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
tiepoint_region_id	int	P/F	X	ID of tiepoint region (primary key).
segment_id	int	P/F	X	segment ID number, from Segment table

Area_Histogram
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
area_histogram_id	int	P	X	Primary Key
analysis_id	int	F	X	Glacier to which this relates (unique), foreign key, from Glacier_Dynamic
bin_width	numeric(5,1)		X	width (in m) of elevation bin
registration	char(1)		X	flag, indicates whether data are bin-centered (C), lower (L), or upper (U) boundary

Area_Histogram_Data
*Field Name*	*Data Type*	*Key*	*Null Allowed*	*Description*
area_histogram_id	int	F	X	foreign key, from Area_Histogram table
elevation	numeric(5,1)		X	representative elevation of bin, m above geoid
area	numeric(9,1)		X	area of glacier in this elevation bin (km2)

Vector_Set
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
vel_set_id	int	P	X	ID of velocity information set
analysis_id1	int	F	X	ID for the first analysis, foreign key from Glacier_Dynamic
analysis_id2	int	F	X	ID for the second analysis, foreign key from Glacier_Dynamic
num_vecs	int			Number of displacement vectors (can be NULL)
loc_unc_first_lon	float			Local uncertainty of first lon (m)
loc_unc_first_lat	float			Local uncertainty of first lat (m)
glob_unc_first_lon	float			Global geolocation uncertainty of first lon (m)
glob_unc_first_lat	float			Global geolocation uncertainty of first lat (m)
loc_unc_second_lon	float			Local uncertainty of second lon (m)
loc_unc_second_lat	float			Local uncertainty of second lat (m)
glob_unc_second_lon	float			Global geolocation uncertainty of second lon (m)
glob_unc_second_lat	float			Global geolocation uncertainty of second lat (m)

Vector
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
vel_set_id	int	F	X	foreign key from Displacement_Info
first_lon	float		X	lon of feature in first image
first_lat	float		X	lat of feature in first image
second_lon	float		X	lon of feature in second image
second_lat	float		X	lat of feature in second image

Image
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
image_id	int	P	X	ID of image in GLIMS
instrument_id	int	F	X	ID of source instrument, from Instrument table
orig_id	varchar(50)			Original ID from data provider (ECS,SPOT,etc)
image_loc_url	varchar(120)			URL of source of image
acq_timestamp	datetime		X	Date/Time of image exposure
image_center_lon	float			Center geodetic longitude of image (WGS-84 ellipsoid)
image_center_lat	float			Center geodetic latitude of image (WGS-84 ellipsoid)
image_center_lon_unc	float			Uncertainty of image georeferencing - lon (m)
image_center_lat_unc	float			Uncertainty of image georeferencing - lat (m)
image_azim	numeric(7,4)			Orientation of image (degrees east of north)
cloud_pct	numeric(3,0)			Cloud severity (0 to 100%, 100% being totally cloudy)
sun_azim	numeric(7,4)			Sun azimuth (degrees east of north)
sun_elev	numeric(7,4)			Sun elevation (degrees from horizon)
instrument_zenith	numeric(7,4)			Zenith angle of instrument pointing (degrees, 0=nadir)
instrument_azimuth	numeric(7,4)			Azimuth of instrument pointing (degrees east of north)
projection	varchar(30)			Name of the projection used (e.g. polar stereographic)

Instrument
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
instrument_id	int	P	X	ID of instrument
instrument_long_name	varchar(50)		X	Long name of instrument
instrument_short_name	varchar(10)			Short name for the instrument
instrument_spacecraft_name	varchar(50)			Name of spacecraft that instrument is on
instrument_altitude	numeric(8,3)			Average orbit altitude (km)
instrument_inclination	numeric(7,4)			Orbit inclination (degrees)
num_bands	int			Number of bands
band_list	varchar(255)		X	List of names of bands/modes
eq_crossing_time	varchar(10)			Time of equator crossing, for sun-synchronous satellites

Band
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
band_id	int	P	X	Band/Mode name (or number)
instrument_id	int	F	X	ID of instrument, from Instrument table
scan_type	varchar(10)			Scan type (whisk, push, etc)
ifov_x	float			Instantaneous field of view, X (radians)
ifov_y	float			Instantaneous field of view, Y (radians)
sample_interval_x	numeric(6,2)			Nominal sample interval X (meters)
sample_interval_y	numeric(6,2)			Nominal sample interval Y (meters)
passband_low	numeric(7,3)			Low edge of passband (nanometers)
passband_high	numeric(7,3)			High edge of passband (nanometers)
passband_unit	varchar(5)			Standard international unit used for the passband
num_bits	int			Number of bits in DN
num_lines	int			Number of lines per nominal scene
num_samples	int			Number of samples per line
polarization	varchar(5)			Polarization (for radar, e.g. HH, VH, etc.)

Image_Band
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
band_id	int	P/F	X	ID of band in this image, from Band table
image_id	int	P/F	X	ID of image cube, from Image table

Glacier_Image_Info
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
analysis_id	int	P/F	X	foreign key from Glacier_Dynamic table
image_id	int	P/F	X	foreign key from Image table

Reference_Document
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
reference_doc_id	int	P	X	Primary Key, ID for the reference document
tag_code	char(2)	P/F	X	Unique identifier for a specific field in reference information
tag_value	varchar(255)		X	Value associated with the tag_code

Reference_Doc_Code
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
tag_code	char(2)	P	X	Unique identifier for a specific field in reference information
tag_code_description	varchar(255)		X	Description of the tag_code(e.g. author name, journal name)

Glacier_Reference
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
glacier_id	varchar(20)	P/F	X	Glacier ID number, from Glacier_Static table
reference_doc_id	int	P/F	X	Reference Document ID number, from Reference_Doc table

Point_Measurement
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
pnt_meas_id	int	P	X	ID of point measurement
glacier_id	varchar(20)	F	X	Glacier that this measurement relates to, from Glacier_Static table
pnt_timestamp	datetime		X	Time stamp for this measurement (e.g. 2005-12-12T14:23:21Z)
pnt_lon	numeric(9,6)		X	x-coordinate of measurement
pnt_lat	numeric(9,6)		X	y-coordinate of measurement
pnt_elev	float			vertical coordinate (geoidal) elevation of measurement (m)
pnt_label	varchar(20)			Label for the measured quantity, e.g. "debris thickness"
pnt_value	float			floating point number representing value of measurement
pnt_lon_unc	float			Uncertainty of lon
pnt_lat_unc	float			Uncertainty of lat
pnt_elev_unc	float			Uncertainty of elevation
pnt_value_unc	float			Uncertainty of point measurement value
pnt_unit	varchar(10)			Unit for measurement (e.g. m, degrees C, etc.)
comment	varchar(250)			Free text to describe measurement, instrument, conditions, etc)

Institution
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
institution_id	int	P	X	ID of institution
institution_name	varchar(100)		X	Name of institution
address	varchar(100)			mailing address of institution
city	varchar(30)			City where institution is located
state	varchar(30)			State where institution is located
country_code	varchar(2)			Country where institution is located, ISO-3166 2-letter code
postal_code	varchar(20)			Postal code (like US ZIP code)
lon	numeric(9,6)			Longitude of institution (for ease of plotting on maps)
lat	numeric(9,6)			Latitude of institution
contact_name	varchar(255)
email	varchar(100)
url	varchar(100)
geog_area	varchar(100)
parent_rc	int			ID of parent RC

Country
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
country_code	char(2)		X	ISO-3166 2-letter code
country_name	varchar(45)		X

Ancillary_Data
*Field Name*	*Data Type*	*Key*	*Not Null*	*Description*
glac_analysis_id	varchar(20)		X	glacier_ID or analysis_ID
location	varchar(100)		X	Location of the ancillary data
data_type	varchar(20)		X	Data type of the ancillary data
size	int
comment	varchar(250)			Free text

GLIMS: Global Land Ice Measurements from Space

Monitoring the World's Changing Glaciers

GLIMS Database Data Dictionary

Previous versions of the data dictionary