The first attempts to use GPS buoys for tsunami detection
were made in Japan (e.g., Teruyuki et al., 2000; Toshihiko et
al., 2006). In 2010, this technology became part of Japans
Nationwide Ocean Wave information system for Ports and
Harbors (NOWPHAS) (Teruyuki et al., 2010).
In 2003 Sch¨one et al. developed an offshore GPS buoy
for multi-mission radar altimeter calibration in the North
Sea. After the deadly tsunami in Banda Aceh (Indonesia)