On Sun 2015-11-08T18:51:37 -0800, Hal Murray hath writ: > Was there a geological incident that explains things?
The crust of the earth has accelerated its rate of rotation during most of the past 100 years. The slowest rotation ever was around 1912, and since then it has been rotating faster. By happenstance, the rate of rotation of the crust was at a local minimum in 1972 at the inception of leap seconds, and since then it accelerated again. > There is another warp in the graph in the late 1980s. Things slowed down for > several year, but not as dramatically as the early 2000s. Don't look at the graph of Delta T, that's effectively the integral of the rate of rotation and its smoothness hides what the slope is telling you. Look at the graph of Length of Day. That integral/derivative pair are the first two graphs at http://www.ucolick.org/~sla/leapsecs/amsci.html For a historic view of the LOD going back 2000 years look at the plots on http://www.ucolick.org/~sla/leapsecs/dutc.html -- Steve Allen <[email protected]> WGS-84 (GPS) UCO/Lick Observatory--ISB Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m _______________________________________________ LEAPSECS mailing list [email protected] https://pairlist6.pair.net/mailman/listinfo/leapsecs
