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Indeed. Leap Seconds need to go and the International Earth Rotation and Reference Systems Service (IERS) needs to get its shit together and ensure that the earth rotates exactly once every 86400 seconds.

Naturally: the earth's rotation must be sped back up to match the clocks.

Time for the International Earth Rotation and Reference Systems Service to get to work on providing that service, then....

(It was better when it was just the International Earth Rotation Service and it was clearer from the name that adjusting the earth's rotation was their job.)

If it turns out that time dilation due to gravity is the reason, then the error must be in the ETRF2000 or it was applied incorrectly in this case (Neutrinos moving from A to B). Considering that hundreds of people work on this project it seems unlikely to me that such an error slipped through. They even took into account the very small distance change induced by the L'Aquila earthquake.

This 2 ms per century drift in the length of a day is an average. The actual variation is far more erratic - so erratic that this sort of thing seems rather likely to be lost in the noise.

[By the way, clock drift here is the integral of the change in the length of the day per day. Hence the disparity.]

The earth is naturally slowing down at a rate that makes this sort of thing hardly worth mentioning.

Actually, the slowdown is only about 2ms/century, or about 0.054 microseconds/day. So a 1-microsecond jump in a day should be noticeable. This information is tracked. Here's the raw data from the Earth Rotation Service.

With GPS systems working down to 15cm, changes like this get noticed.

Lunakhod 1 carried a French retroreflector array for Lunar Laser Ranging (LLR) but unfortunately, contact was lost and no one knows where it is. There are good returns for Lunakhod 2, so I (and others) want Lunakhod 1 back !

Finding this would be a great help for Lunar science (assuming it didn't get crushed in a landslide or something). I know that this is on their list, so good luck !

There is a drift, and there are fluctuations.

Regarding the drift: The day length is getting gradually longer by about 1.7 milliseconds every century (+2.3ms due to tidal braking, -0.6ms due to glacial rebound). In about 1820 the day was 86400 seconds; now it is longer than that. In a thousand years, the day will be about 86400.017 seconds, and we will need a leap second every couple of months.

[Note: I am simplifying a little here for the sake of clarity by ignoring the difference between a solar day and the stellar and sidereal days, which are about 4 minutes shorter].

Regarding the fluctuations: There are fluctuations of the earth's angular velocity on many timescales. It fluctuates with weather, with the seasons, and with major events on the surface (e.g. a dam creating a new reservoir) and in the earth's crust (e.g. an earthquake or major volcanic eruption) and deeper interior (e.g. we don't really know). All these events are minor rearrangements of the mass of the earth, which change its moment of inertia. Conservation of angular momentum dictates that the angular velocity must change, and it does. Of course the earth isn't a rigid body and that complicates all this. Learn about Geodesy if you want to know more.

In the 1990s the day length was approximately 86400.003 seconds, so we needed a leap second every year. For poorly-understood reasons (possibly some sort of deep mantle activity), the earth's rotation speeded up around the year 2000, and for a while the day length was about 86400.0004 seconds. Now it is slower again, about 86400.001 seconds. These changes all come under the "fluctuations" heading.

There is an organisation called the IERS - International Earth Rotation and reference Systems Service - which collects measurements of all this stuff to very high accuracy and produces all sorts of reports, bulletins, data sets, etc etc.

The annual variation in length-of-day is about two milliseconds. This is mainly due to seasonal changes in ocean currents and major storms.

Most of the annual effects and zonal tidal effects are actually quite regular, which can be seen in the graphs. But over long time scales they'll average out, which implies this one event may actually be somewhat significant on top of that.

But on the other hand, it might not be significant, as the top graph shows the much slower variation due to Earth liquid core. Those effects don't seem to have regularity (they might over thousand-year timescale), and compared to them 3us is pretty small.

However, what makes the quake's impact different from the seasonal/zonal variations is that it's one incident that caused such a change. They also mention 1983 El Niño as another significant even too.

The length of a day fluctuates two milliseconds, or a thousand times more, over the course of a year. Most of this attributed to the annual pattern of ocean storms.

In fact, UTC time doesn't exactly reflect the earth's rotation. Its seconds are real SI seconds (cesium stuff you know) but it is adjusted to follow earth rotation one second at a time and very rarely.

For more information read this and this.

No, your wristwatch doesn't need to be readjusted immediately.

CNN Says:

For 28 years, scientists repeated the procedure [of adding a leap second]. But in 1999, they discovered the Earth was no longer lagging behind.

Um, not exactly true. Not every year over the last 28 years has had a leap second. For example, 1984, 1986 and 1987 didn't have a leap second. It's generally determined if a leap second is necessary about 6 months ahead of time by IERS. However, this is the first 5 year gap of no leap seconds.

It's interesting to note that the "leap second protocol" permits a "reverse" leap second - meaning a "short" minute. This is because the folks involved in defining the leap second realized that the rotation of the earth is not 100% predictable, and therefore they theorized that there could be a "fast spinning year" that would merit the loss of a second. This hasn't happened yet.

This whole rotation-of-earth-isn't-constant idea is pretty new (50 years). So just because we have a 5 year period of smaller rotaional speed deltas isn't totally unexpected.

The IERS has a plot showing how the length of day has decreased over the past few years. Curiously, the current phase of accelerated rotation of the crust began right around the time we started adding leap seconds to UTC.

UTC is a mess. I'd rather see all computer clocks use TAI (International Atomic Time) internally.

Have you ever worried about who is responsible for making sure the Earth is rotating? Check the International Earth Rotation Service website.

Actually, it's much more bureaucratic then that. No superheroes involved, just your run-of-the-mill civil servants.
Here's the homepage for the International Earth Rotation Service
Be sure to keep paying you monthly rotation bills!

All of these measurements are made under the purview of the International Earth Rotation Service. There are models for all manner of astrophysical and geophysical effects considered in the Conventions that are used when reducing the data.

The way that solar noon is kept at civil time noon is by inserting leap seconds. In most places civil time is offset directly from UTC. When a leap second is inserted the day is 86401 seconds long.

This irregularity upsets some kinds of timekeeping systems, and as a result there has been discussion that leap seconds should be abolished. That would cause noon to drift away from noon. That may not be a good thing.

All of these measurements are made under the purview of the International Earth Rotation Service. There are models for all manner of astrophysical and geophysical effects considered in the Conventions that are used when reducing the data.

The way that solar noon is kept at civil time noon is by inserting leap seconds. In most places civil time is offset directly from UTC. When a leap second is inserted the day is 86401 seconds long.

This irregularity upsets some kinds of timekeeping systems, and as a result there has been discussion that leap seconds should be abolished. That would cause noon to drift away from noon. That may not be a good thing.