Published online by Cambridge University Press: 03 August 2017
The strong water maser line at 22 GHz is an excellent tool for studying shocked and turbulent interstellar regions, especially, if simultaneous single-dish and VLBI data are available. After a brief review of 22 GHz time variation studies, we focus on effects caused by magnetic field pressure on observed properties of water masers. We use the powerful and rich maser cluster W49N as an example. Furthermore, we point out the connection between postshock wave damping and observed excess in single-dish flux density and line width.