Full information on AMS copyright policies is available here.
Before a paper is published, all authors on the paper must submit an appropriate signed Copyright Form transferring copyright to the American Meteorological Society or verifying that the copyright is held by the U.S. Government or the Crown. As coauthors on a paper may be employed at different institutions, it is acceptable for some authors to transfer copyright to the AMS while other authors on the same paper sign U.S. Government or Crown certification forms.
Corresponding authors may upload signed copyright forms when submitting new papers or revisions, but the forms are not required until after acceptance. After acceptance, AMS staff will contact the corresponding author with instructions for submitting forms.
Faxed or scanned versions of the forms are acceptable (there is no need to mail a paper copy to the AMS). It is acceptable for each author of a paper to provide a separate form with his or her signature. Electronic Signatures are acceptable (Nov 20, 2012).