Coordinated Universal Time (UTC) is the internationally applicable world time standard. In seismology, it is used to make international earthquake data easier to compare and utilise by eliminating the complications associated with different time zones and hemispheres.
Coordinated Universal Time was introduced in 1972 and corresponds to Greenwich Mean Time, i.e. the time along the prime meridian running through the observatory located in the London borough of Greenwich. Time zones west of the prime meridian are behind UTC, while those to the east are ahead of it.
UTC follows the highly precise second-based International Atomic Time (TAI). Since the Earth’s rotation can fluctuate and a day can therefore last longer than 24 x 3,600 seconds, from time to time a leap second is added.
Standard time in Switzerland is Central European Time (CET), which is one hour ahead of UTC (UTC +1). Central European Summer Time (CEST) is two hours ahead of UTC (UTC +2).
UTC time zones