| Cubic meters (m³) | Teraliters (TL) |
|---|---|
| 1 Cubic meter | 0.000000001 TL |
| 2 Cubic meters | 0.000000002 TL |
| 3 Cubic meters | 0.000000003 TL |
| 4 Cubic meters | 0.000000004 TL |
| 5 Cubic meters | 0.000000005 TL |
| 10 Cubic meters | 0.00000001 TL |
| 20 Cubic meters | 0.00000002 TL |
| 25 Cubic meters | 0.000000025 TL |
| 50 Cubic meters | 0.00000005 TL |
| 100 Cubic meters | 0.0000001 TL |
| Reference | Cubic meters (m³) | Teraliters (TL) |
|---|---|---|
| A teaspoon | 0.000005 m³ | 5 × 10-15 TL |
| A can of soft drink | 0.00033 m³ | 3.3 × 10-13 TL |
| A wine bottle | 0.00075 m³ | 7.5 × 10-13 TL |
| A bathtub | 0.15 m³ | 1.5 × 10-10 TL |
| An Olympic swimming pool | 2500 m³ | 0.0000025 TL |
The cubic metre is the SI unit of volume, written m³. It is the volume of a cube one metre on each side, and because the metre is a base unit, every other volume unit in the system is derived from it. It holds a thousand litres, and a cubic metre of fresh water has a mass of very nearly one tonne, which is the single most useful fact about it.
Utilities are billed in it. Domestic water meters almost everywhere record consumption in cubic metres, and a household of four uses somewhere between 100 and 200 of them a year. Natural gas is metered the same way and then converted to energy for billing, because the heat released by a cubic metre of gas depends on its composition and has to be corrected for temperature and pressure at the meter.
Construction orders materials by it. Ready-mixed concrete is sold and delivered by the cubic metre, a standard truck carrying six to eight; excavation and earthworks are priced per cubic metre moved; and sawn timber, aggregate, topsoil and bark are all traded the same way. Because a cubic metre of concrete weighs about 2.4 tonnes, the unit also decides what a lorry or a crane can carry.
Freight uses it in a more subtle way. Shipping and removals quote volume in cubic metres, and air freight charges by whichever is greater, the actual mass or a volumetric mass calculated at a fixed ratio, commonly 167 kilograms to the cubic metre. Light bulky cargo is therefore priced by the space it occupies rather than by what it weighs, and the whole calculation runs on this unit.
Environmental measurement lives here too. River flow is given in cubic metres per second, reservoir capacity in millions of cubic metres, air quality as micrograms of pollutant per cubic metre of air, and ventilation as cubic metres per hour. A room four metres by five with a ceiling at two and a half holds fifty cubic metres of air, which is the sort of figure ventilation standards are written against.
Against imperial and United States units it converts to 35.315 cubic feet or 1.308 cubic yards. The cubic yard matters most in practice, because American concrete and excavation are ordered in it, and the two units are close enough that a mistaken figure looks plausible while being a third out.
One cubic metre equals 1000 litres, about 35.315 cubic feet, about 1.308 cubic yards, or about 264.2 US gallons.
The teralitre is a unit of volume equal to a thousand gigalitres, or 1,000,000,000,000 litres. Its symbol is TL. It is exactly one cubic kilometre, and that is how the quantity is almost always written, because at this scale what is being measured is no longer a container but a piece of the planet.
Lakes are the obvious application. Lake Baikal holds about 23,600 cubic kilometres of fresh water, more than any other lake on earth, and Lake Superior about 12,100. Those two figures alone amount to a fifth of the world's unfrozen surface fresh water, which is the kind of statement the unit exists to make.
Rivers are described by the volume they move rather than by what they hold. The Amazon discharges roughly 6600 cubic kilometres a year into the Atlantic, more than the next several rivers combined, and total human withdrawal of fresh water from all sources runs to about 4000 cubic kilometres a year. Setting those two numbers side by side in the same unit is one of the clearest ways to state the scale of water use.
Ice is measured here too, and the numbers are larger again. The Greenland ice sheet contains close to 2.9 million cubic kilometres, and in recent decades it has been losing a few hundred each year, a figure that converts directly into millimetres of sea level because the ocean's surface area is known. The Antarctic sheet is an order of magnitude larger still.
The ocean itself sets the ceiling. All the seawater on earth amounts to about 1.335 billion cubic kilometres, so a single teralitre is roughly one billionth of it. Below the ocean, the largest managed water bodies are engineered reservoirs, and even the biggest of those hold only a few tens of cubic kilometres.
In practice the name teralitre is rare and the cubic kilometre is standard. Hydrology, glaciology and climate science all use km³, and a figure given in teralitres is more likely to come from a water utility extending its own gigalitre scale upward than from a scientific source. The two are identical, so no conversion is needed, only recognition.
One teralitre equals 1,000,000,000,000 litres, 1,000,000,000 cubic metres, 1 cubic kilometre, or 1000 gigalitres.