Below are links to the tools currently available:
teKML
Time-Enabled KML Conversion Library - is a Java API and commandline application for converting geodata vector files with time attributes into KML with time elements.
HGL Desktop Tool
This extension allows users to search the extensive holdings of the Harvard Geospatial Library and access the data directly from within the ArcMap software package.
For questions concerning these applications, contact CGA by email.