IERS

I get the IERS statements like clockwork every thursday. However, they simply tell us when the gov't adds or subtracts a second from the atomic clock times so that things come out evenly. Unfortunately, unless we look at the data for long periods of time we won't know the difference, and there is some real doubt as to whether it is being reported accurately. I suggest setting your watches on atomic time from the clock connections, and puting about 10 of them in a safe and coming back six months later. Take the average of all your lithium battery watches (throw out any that are really off), and compare it to vcurrent atomic clock time then. If the difference is more that 10 seconds, we have a problem.

The satellite-geodesy programs used in the IERS give access to the time variations of the Earth's gravity field, reflecting the evolution of the Earth's shape, as well as the redistribution of masses in the planet. They have also detected changes in the location of the centre of mass of the Earth relative to the crust. This makes it possible to investigate global phenomena such as mass redistributions in the atmosphere, oceans and solid Earth. Universal time and polar motion are available daily with an accuracy of 0.5 mas and celestial pole motion are available every five to seven days at the same level of accuracy - this estimation of accuray includes both short term and long term noise. Sub-daily variations in Universal time and polar motion are also measured on a campaign basis.

Offered by Eric

There is a big problem with locking several watches away and taking an average from them. For one thing, a watch crystal's frequency is affected by temperature and a carefully calibrated watch takes into account the body heat of the wearer. So, if you have several watches at room temperature they will all be biased in one direction thus skewing the average. If you really want to know what is going on with time corrections try finding a non-government entity with an atomic clock to see what they have observed. Some broadcasters use atomic clocks as frequency standards, also check with universities and astronomers.

Offered by Steve.