The 2012 National Tsunami Response Plan outlines Tonga’s tsunami warning and mitigation system. Since 2012 there have been evolution of practice contributed by the following events.

• In 2016, TC Winston the five Broadband seismic stations sustained damage rendering it non-operational and deeply affected the functions of the Tonga Geological Services to deliver it’s functions under the 2012 NTRP.
• Hunga-Tonga Hunga Ha’apai Volcanic eruption that triggered a tsunami exposed the ongoing challenges in capacity and also the limitation of the 2012 NTRP. The 2012 only covers tsunamis generated by earthquakes. It is silent on tsunami generated by volcanoes.

In addition, the recent PacWAVE22 and 2023 National Tsunami Drill Exercise identified critical lessons learnt to be considered in the review and update of each agency SOP and the 2012 NTRP. The lessons learnt also highlighted the demand on agency capacity and the need for remedial actions to strength tsunami warning and mitigation system in Tonga.

The evolution of tsunami generated risks have re-shaped practice and demand on capability set the impetus to strengthen tsunami specific monitoring, detection, warning and response plans and SOP for NRD, NDRMO and TMS. The UNESCO/IOC Tsunami Ready Recognition Programme provides the opportunity to strengthen the National SOP with the alignment of agency-specific SOP and eventually aligned community tsunami  SOP.

The Joint Review of Tsunami SOP in Tonga have the following objectives.

1. To review each agency Tsunami warning and response SOP.
2. To   align actions of each agency against each Alert level to remove confusion.
3. To identify capacity needs for each agency to support their actions stated in the SOP
4. To identify interventions to address capacity needs of each agency SOP.
5. To identify gaps within the 2012 National Tsunami Response SOP
6. To incorporate the updated SOPs into the National Tsunami Response Plan
7. To identify interventions to address Gaps in the 2012 national Tsunami Response Plan P.
8. To map out UNESCO/IOC Tsunami Ready Recognition Implementation Programme