(See the article on International Atomic Time for details.)

The International Atomic Time is calculated there.

Although the best model adds a quadratic term to defined International Atomic Time, the team encountered problems with this theory.

Therefore, many scientific applications that require precise measurement of long (multi-year) intervals use International Atomic Time instead.

International Atomic Time (French: Temps atomique international)

These clocks collectively define a continuous and stable time scale, International Atomic Time (TAI).

The technique is commonly used for creating and distributing standard time scales such as International Atomic Time (TAI).

LOD, the length of a mean solar day in a uniform time scale such as International Atomic Time; see ΔT.

Practical examples include the International Atomic Time standard and its relationship with the Barycentric Coordinate Time standard used for interplanetary objects.

The basis for scientific time is a continuous count of seconds based on atomic clocks around the world, known as the International Atomic Time (TAI).

Additionally, a reference hydrogen maser is also reported to BIPM as a frequency standard for TAI (international atomic time).

TT indirectly underlies UTC, via International Atomic Time (TAI).

International Atomic Time (TAI) is the primary international time standard from which other time standards, including UTC, are calculated.

One is called International Atomic Time, or TAI, which is computed by the International Bureau of Weights and Measures in Paris.

Together with other kinds of atomic clocks, these help make up the International Atomic Time ("Temps Atomique International" or "TAI" in French).

With the advent of the atomic clock it has been possible to define and measure International Atomic Time with sufficient precision that variations in the Earth's rotation can be detected.

It is also answered that two timescales that do not follow leap seconds are already available, International Atomic Time () and Global Positioning System (GPS) time.

To millisecond accuracy, TT runs parallel to the atomic timescale (International Atomic Time, TAI) maintained by the BIPM.

UTC (MSL) is kept within 200 nanoseconds of the international atomic time scale maintained by the Bureau International des Poids et Mesures (BIPM) in Paris.

Losing only a second of accuracy every 1.6 million years, it remains the most accurate commercial clock in the world, and accounts for 82% of the data used to keep the International Atomic Time Standard (as of 2006).

In the synchronous grid of Continental Europe, the deviation between network phase time and UTC (based on International Atomic Time) is calculated at 08:00 each day in a control center in Switzerland.

International Atomic Time (TAI, from the French name Temps atomique international) is a high-precision atomic coordinate time standard based on the notional passage of proper time on Earth's geoid.

Today, the fundamental unit of time suggested by the International System of Units is the second, since 1967 defined as the second of International Atomic Time, based on the radiation emitted by a Caesium-133 atom in the ground state.

Nowadays, UT in relation to International Atomic Time (TAI) is determined by Very Long Baseline Interferometry (VLBI) observations of distant quasars, a method which can determine UT1 to within 4 milliseconds.

Since 1972 UTC is calculated by subtracting the accumulated leap seconds from International Atomic Time (TAI), which is a coordinate time scale tracking notional proper time on the rotating surface of the Earth (the geoid).