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>From: "Stuart Wier" <address@hidden> >Organization: UNAVCO >Keywords: 200508192127.j7JLRL4Y004563 IDV years Hi Stuart- >Institution: UNAVCO >Package Version: - >Operating System: linux >Hardware Information: the usual >Inquiry: Working with mantle convection flow in the IDV, I am seeing data with > times in million years before present. (mybp) >How do you represent that in ud units? This is a standard in geology and geoph > ysics, or if it does not meet the dictionary definition of standard, let's ju > st say everyone in solid earth sciences knows what it means. I suppose second > s since 1/1/1970 is not a good idea. It depends how you want to specify the present. It will be different tomorrow than today. ;-) The best way would be to specify a base time for "present". Then, you could use: -1 Ma since 2005-01-01 which would give you one million years before the first of January. (there's a bug which would cause an error if you specify -1.0, so for now use -1). The labels in the IDV will probably not handle this gracefully, but the it should handle the conversions. Don Murray NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.