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To convert from meter of water @ 4°C (mH2O) to millibar (mbar), use the following formula:
Let's convert 5 meter of water @ 4°C (mH2O) to millibar (mbar).
Using the formula:
Therefore, 5 meter of water @ 4°C (mH2O) is equal to millibar (mbar).
Here are some quick reference conversions from meter of water @ 4°C (mH2O) to millibar (mbar):
| meters of water @ 4°C | millibar |
|---|---|
| 0.000001 mH2O | mbar |
| 0.001 mH2O | mbar |
| 0.1 mH2O | mbar |
| 1 mH2O | mbar |
| 2 mH2O | mbar |
| 3 mH2O | mbar |
| 4 mH2O | mbar |
| 5 mH2O | mbar |
| 6 mH2O | mbar |
| 7 mH2O | mbar |
| 8 mH2O | mbar |
| 9 mH2O | mbar |
| 10 mH2O | mbar |
| 20 mH2O | mbar |
| 30 mH2O | mbar |
| 40 mH2O | mbar |
| 50 mH2O | mbar |
| 100 mH2O | mbar |
| 1000 mH2O | mbar |
| 10000 mH2O | mbar |
For all Pressure converters, choose units using the From/To dropdowns above.
A meter of water @ 4°C (mH2O) is a metric unit used to measure pressure.
It is precisely defined as 9.80665 kilopascals (kPa).
The specific temperature of 4°C (39.2°F) is key because this is the point where pure water is at its heaviest or most dense (approximately 999.972 kg/m3).
Using this temperature provides a stable and reliable standard for defining pressure.
This precision is essential in scientific and engineering fields like hydraulics and fluid mechanics, ensuring that measurements of pressure head are consistent and accurate across different applications and locations.
The unit "meter of water" (mH2O) is frequently used in civil engineering, hydrology, and irrigation to measure water levels and pressure.
It provides an intuitive way to express the pressure exerted by a column of water, such as the water level in a reservoir, dam, or groundwater well. This measurement is sometimes referred to as the 'piezometric head'.
It is also commonly used to specify the performance of pumps, indicating the height to which a pump can lift water.
For practical use, it's often helpful to know how mH2O converts to other common pressure units.
One mH2O is equal to:
These conversion factors allow engineers and scientists to easily translate pressure specifications between different international and imperial systems.
A millibar (mbar) is a metric unit used to measure atmospheric pressure.
It's most commonly used in weather forecasting and reporting.
(Technically, one millibar is equal to 0.1 kilopascal, or kPa).
Meteorologists use millibars as the primary unit to measure and report atmospheric pressure.
On weather maps, you'll see lines called isobars, which connect areas of equal pressure, drawn in millibar intervals.
Standard atmospheric pressure at sea level is about 1013 mbar.
This number is a key benchmark for weather conditions:
Yes, for all practical purposes, a millibar (mbar) and a hectopascal (hPa) are the same.
The two units are used interchangeably.
The conversion is simple: 1 mbar = 1 hPa.
While you'll still see millibars in public weather reports (especially in the U.S.), the hectopascal is the preferred SI (International System of Units) unit for global scientific consistency.
A barometer measures barometric pressure—the weight of the air above you—using millibars.
Watching the change in this reading is key to predicting the weather: