Inside the AHO

Frequently Asked Questions (FAQ's)

We have compiled a suite of Fact Sheets to address frequently asked questions. However, if you have any further queries, please contact us.

Glossary

There are many words, phrases and acronyms used in hydrographic applications. Below you can find a concise list of these as well as links to other related glossaries of Hydrographic terms.

Glossary of Acronyms and Abbreviations

ACI Australian Chart Index
ACT Australian Capital Territory
ADF Australian Defence Force
AGD Australian Geodetic Datum
AHO Australian Hydrographic Office
AHS Australian Hydrographic Service
AMSA Australian Maritime Safety Authority
ANTT Australian National Tide Tables
ARCS Admiralty Raster Chart Service
dGPS Differential Global Positioning System
DGST Deployable Geospatial Support Team (formerly known as Hydrographic Office Deployable Survey Unit (HODSU)).
DHDB Digital Hydrographic Database
ECDIS Electronic Chart Display and Information System
ECS Electronic Chart Systems
ENC Electronic Navigational Chart
FAQ Frequently Asked Questions
GDA Geocentric Datum of Australia
GeoTIFF Geographic Tagged Image File Format - The Australian Hydrographic Service produces charts in GeoTIFF format known as AusGeoTIFF.
GPS Global Positioning System. A positioning system calculated from orbiting satellites.
HAT Highest Astronomical Tide. A tidal datum. The highest level of water which can be predicted to occur under any combination of astronomical conditions.
HCRF Hydrographic Chart Raster Format.
HI Hydrographic Instruction
Hydrographic Note A Hydrographic Note is a form used to notify the Hydrographer, when new or suspected dangers to navigation are discovered, changes observed in aids to navigation, or corrections to publications are seen to be necessary.
HS Hydrographic Ship
IC-ENC International Centre for ENCs - An association of national hydrographic organisations for the distribution of official Electronic Navigational Charts. The IC-ENC is a Regional ENC (or RENC).
IHB International Hydrographic Bureau - The headquarters of the International Hydrographic Organization.
IHO International Hydrographic Organization - The organisation which coordinates world hydrographic charting policy and standards.
IMO International Maritime Organization - The United Nations organisation which coordinates safety policy and standards for world shipping.
ISLW Indian Springs Low Water. A tidal datum originated by Sir G. Darwin when investigating tides of India. An elevation depressed below mean sea level by the amount equal to the sum of amplitudes of the four main harmonic constituents: M2, S2, K1 and O1.
IT Information Technology
LADS Laser Airborne Depth Sounder
LAT Lowest Astronomical Tide - A tidal datum. The lowest tide level, which can be predicted to occur under average meteorological conditions and under any combination of astronomical conditions. Increasingly used as chart datum, for example,. for all new Australian charts.
MGA The Maritime Gazetteer of Australia
MGI Military Geospatial Information
NSW New South Wales
NT Northern Territory
NtM Notices to Mariners
PNG Papua New Guinea
QLD Queensland
RAN Royal Australian Navy
RCDS Raster Chart Display System
S57 The International Hydrographic Organization (IHO) data format and specification which governs the content, creation and display of Electronic Navigational Charts (ENCs).
S63 IHO data protection standard for the protection of ENC information.
SA South Australia
SMB Survey Motor Boat
SML Survey Motor Launch
SOLAS Safety of Life at Sea Convention - The principal international convention regulating ship safety. Administered by the International Maritime Organization (IMO).
UT Universal Time - Also known as Greenwich Mean Time (GMT) and Zulu Time (military term).
TAS Tasmania
VIC Victoria
VTS System Vessel Traffic Services System
WA Western Australia
WEND World-wide Electronic Navigational Chart Database
WGS World Geodetic System