Andrew Perry Ingersoll is a professor of planetary science at the California Institute of Technology... (wikipedia)
Pockets of liquid water may be no more than tens of meters below the surface.
Other moons in the solar system have liquid water oceans covered by kilometers of icy crust. What's different here is that pockets of liquid water may be more than tens of meters below the surface.
It's really the only large storm on the whole planet. It's in the right place and it appeared at the right time to match the radio emissions, so it has to be the right storm.
It's really the only large storm on the whole planet.