Australian Water Information Dictionary

Alphabetical list of items

A   B   C   D   E   F   G   H   I   K   L   M   N   O   P   Q   R   S   T   U   V   W   Y   Z   other  

M

/

m

The abbreviation for metre(s).

This definition applies to:

mAHD

The abbreviation for elevation in metres with respect to the Australian Height Datum.

Related: Australian height datum

This definition applies to:

major flooding

In addition to the criteria for moderate flooding, extensive rural areas and/or urban areas are inundated. Properties and towns are likely to be isolated and major traffic routes likely to be closed. Evacuation of people from flood affected areas may be required.

Related:

This definition applies to:

major storage

Any water storage that has a total storage capacity of 1000 million litres or more.

Source: Water Regulations 2008 Schedule 3 Part 1. For the latest information on Australian Government law please go to Federal Register of Legislation

This definition applies to:

managed aquifer recharge

There are multiple contexts for this item

Context 1

The volume of water deliberately moved to groundwater assets from other water assets (such as surface water) due to human intervention.

This definition applies to:

Context 2

The deliberate adding of water to an aquifer.

This definition applies to:

managed groundwater volume

An average annual groundwater volume available for extraction usually estimated by jurisdictions for each managed groundwater management unit. This volume has different names in different jurisdictions, for example permissible consumptive volume, volume available for extraction, groundwater availability and these volumes are usually presented and explained in documents such as Water Sharing Plans and Water Resource Plans. The intent is usually to manage the total of all groundwater allocations so that allocations do not exceed the managed groundwater volume. Furthermore this volume may be adjusted annually to reflect the status of the groundwater resource (and allocations would be adjusted accordingly).

This definition applies to:

manual monitoring

Operating sensors or instruments by hand to collect measurements of a parameter. This can include regular or irregular measurements.

Synonym: discrete monitoring

This definition applies to:

materiality

Information is material if its omission or misstatement could influence the water-related decisions made from using the general purpose water accounting report. Materiality depends on the impact of the nature and amount (volume, value or other attribute) of the item or error. It is influenced by the circumstances in which the information is presented and how it affects the decision-making process.

This definition applies to:

may

Indicates an allowable option.

This definition applies to:

MDB

Murray–Darling Basin

This definition applies to:

mean seasonal storage range

Expresses the estimated mean seasonal range in the amount of water stored in all water stores (surface, soil and groundwater). A large range is likely to indicate a large use of water from storage during periods with low rainfall, for example through root water uptake from deeper soil or groundwater stores.

Source: Van Dijk, A., Warren, G., Van Niel, T., Byrne, G., Pollock. D., Doody, T., (2011). Derivation of data layers from medium resolution remote sensing to support mapping of groundwater dependent ecosystems. CSIRO Land and Water, Internal Document for National Water Commission GDE Atlas.

Related: MSSR

This definition applies to:

measurement uncertainty

A parameter, associated with the result of a measurement, that characterises the dispersion of values that could reasonably be attributed to the measurand.

Source: ISO/IEC Guide 98-3:2008. © Standards Australia Limited. Copied by the Australian Government Bureau of Meteorology with the permission of Standards Australia and Standards New Zealand under Licence 1901-c052.

It describes a range of possible values of the quantity being measured (the measurand) that fall around the true value, and indicates a level of confidence that the true value lies within a defined uncertainty range. The ‘true value’ is the result that would be obtained if a 'perfect' measurement were made. However, all measurements have a degree of uncertainty regardless of precision and accuracy. Factors that may contribute to uncertainty include limitations of measuring systems, measurement techniques and behaviours of the natural system being measured that cannot be controlled during the measurement.

This definition applies to:

measuring point

A place where a particular parameter is measured within a site. Typically, this is where a sensor is located or where the observation is made.

This definition applies to:

median

The middle number of a given sequence of numbers. When the sequence contains an even amount of numbers, the median is the mean of the two middle values.

Source: The first part of definition sourced from Macquarie Dictionary Fifth Edition, 2009, Macquarie Dictionary Publishers.

This definition applies to:

megalitre

One million litres.

Synonym: ML

This definition applies to:

Mesozoic

An interval of geological time from about 250 million years ago to about 65 million years ago.

Source: USGS publication: Division of geological time - Major Chronostratigraphic and geochronologic units

Related:

This definition applies to:

metadata

Information about a resource

Source: AS/NZS ISO 19115.1:2015. © Standards Australia Limited. Copied by the Australian Government Bureau of Meteorology with the permission of Standards Australia and Standards New Zealand under Licence 1901-c052.

This definition applies to:

meteorological features

Those physical features that relate to atmospheric phenomena, especially weather and weather conditions. For example, the land surface or the atmosphere.

Related:

This definition applies to:

metrological confirmation

A set of operations required to ensure that measuring equipment conforms to the requirements for its intended use.

Source: ISO 9000:2015. © Standards Australia Limited. Copied by the Australian Government Bureau of Meteorology with the permission of Standards Australia and Standards New Zealand under Licence 1901-c052.

This definition applies to:

metrology

The science of measurement, embracing both experimental and theoretical determinations at any level of uncertainty in any field of science and technology.

Source: Bureau International des Poids et Mesures, viewed 05 December 2018.

This definition applies to:

MGA2020

Map Grid of Australia 2020

The standard map projection associated with GDA2020. It is a transverse Mercator projection that conforms to the internationally accepted Universal Transverse Mercator Grid system.

Source: Intergovernmental Committee on Surveying and Mapping, viewed 05 December 2018.

This definition applies to:

MGA94

Map Grid of Australia 1994

The standard map projection associated with GDA94. It is a transverse Mercator projection that conforms to the internationally accepted Universal Transverse Mercator Grid system.

Source: Intergovernmental Committee on Surveying and Mapping, viewed 05 December 2018.

This definition applies to:

Millennium drought

The prolonged period of dry conditions experienced in much of southern Australia from late 1996 to mid-2010.

Source: Modified from the Bureau's Climate updates, viewed 25 July 2015.

Related: drought

This definition applies to:

minimum supply level

The lowest water level to which a water storage can be drawn down (0% full) with existing outlet infrastructure; typically equal to the level of the lowest outlet, the lower limit of accessible storage capacity. See the water storage diagram for more information.

Related: accessible storage capacity

This definition applies to:

minor flooding

Causes inconvenience. Low-lying areas next to watercourses are inundated which may require the removal of stock and equipment. Minor roads may be closed and low-level bridges submerged.

Related:

This definition applies to:

minor storage

Any water storage in which water is stored for taking and that meets the following criteria: (a) it is not a major storage; (b) it has a storage capacity of 100 million litres or more; (c) it is not used primarily for the precipitation of ash; (d) it is not a mine tailings dam; (e) it is not managed by an urban infrastructure operator primarily for the purposes of flood management or pollution abatement.

Source: Water Regulations 2008 Schedule 3 Part 1. For the latest information on Australian Government law please go to Federal Register of Legislation

This definition applies to:

ML

megalitre

One million litres.

This definition applies to:

ML/d

The abbreviation for megalitres per day. A unit of measure for instantaneous discharge (rate unit).

This definition applies to:

moderate flooding

In addition to the criteria for minor flooding, the evacuation of some houses may be required. Main traffic routes may be covered. The area of inundation is substantial in rural areas requiring the removal of stock.

Related:

This definition applies to:

MODIS

MODerate resolution Imaging Spectrometer – a sensor mounted on NASA’s TERRA and AQUA satellites that orbits the Earth collecting data in visible and infrared wavelengths. The data used in this project was the MOD43B4 Nadir BRDF (NBAR) product disseminated by NASA and post-processed by CSIRO.

Source: Paget, M.J. and King, E.A., (2008). MODIS Land data sets for the Australian region. CSIRO Marine and Atmospheric Research internal report 004, CSIRO Canberra, Australia, ISBN 978192142432(pdf).

This definition applies to:

Modèle du Génie Rural à 4 Paramètres Journalier

A daily lumped four-parameter rainfall-runoff model, belonging to the family of soil moisture accounting models.

Source: Perrin, C., Michel, C., & Andréassian, V. 2003, Improvement of a parsimonious model for streamflow simulation. Journal of Hydrology, 279(1), 275-289.

This definition applies to:

monitoring site

A place where observations of the environment are made; typically a physical location where sensors are used to measure the properties of one or more features of the environment (e.g. depth of a river and temperature of the atmosphere).

Related: feature

Synonym: site

This definition applies to:

monitoring site catalogue

A systematic collection of information about a set of monitoring sites.

Related: monitoring site

This definition applies to:

monsoon

The northern Australian monsoon season generally lasts from December to March. It is associated with the inflow of moist west to northwesterly winds into the monsoon trough, producing convective cloud and heavy rainfall over northern Australia. These moisture-laden winds originate from the Indian Ocean and southern Asian waters. The northern Australian wet season encompasses the monsoon months but can extend several months either side. See the Weather and Climate page on the Australian monsoon for more information.

This definition applies to:

month

One of the 12 months of the calendar year (e.g. January).

Source: Water Regulations 2008 Regulation 1.04. For the latest information on Australian Government law please go to Federal Register of Legislation

This definition applies to:

MSL

Minimum Supply Level

This definition applies to:

MSSR

mean seasonal storage range

Related: mean seasonal storage range

This definition applies to:

multipatch feature class

A GIS object that stores a collection of patches to represent the boundary of a three dimensional object as a single row in a database.

Source: ArcGIS Help 10.1

Related: feature class

This definition applies to: