On Sat 2016-04-23T14:08:12 -0700, Tom Van Baak hath writ: > > How far back do we have to go before we have multiple leap seconds *per > > day* ? > > Attached are two plots that go back 380k years. The MSL (mean sea > level) is from ice core data and the LOD (length of day) is derived. > Somewhere in the archives are posts with either these plots or the > paper(s) they came from, or other information about LOD, sea level, > and climate. > > So not a leap second a day, but a leap second a week would be > common. Note 100 meter sea level changes are common too.
My number of around 50 ka does not distinguish glacial LOD changes from secular acceleration. These LOD plots exclude secular acceleration. > Realize that these are beyond even "Long Now" sorts of concerns, and > probably shouldn't be allowed to impact current leap second proposals > or pUTC design decisions. Definitely true. -- Steve Allen <s...@ucolick.org> 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 LEAPSECS@leapsecond.com https://pairlist6.pair.net/mailman/listinfo/leapsecs