A geomagnetic jerk for the end of the 20th century?

The series of magnetic measurements at some European observatories give some hint of a new geomagnetic jerk around 1999. The geomagnetic impulses would present the remarkable and intriguing property to occur with a frequency of one per decade, in the last third of the 20th century. The geomagnetic jerks have been proposed to be indicators which anticipate the changes in the Earth's rotation rate. If this statement is of general validity, the 1992 jerk should be followed by an acceleration of the Earth rotation which would take place now. And, along the same lines, we might predict a new deceleration in less than 10 yr. (C) 2000 Elsevier Science B.V. All rights reserved.