The Pacific Sea Level and Geodetic Monitoring, or PSLGM, is a network that provides vital sea level data for decision-making.

So the tide stations, they measure sea level to a high degree of accuracy. So we have a network throughout the Pacific of 14 tide stations, which form part of the Pacific Sea Level and Geodetic Monitoring Project (PSLGM), which operates under COSPPac.

For the decision-makers, it is very important to understand how much there is a sea level rise, or the sea level fall.

The information received from this tide gauge is a contribution towards reality that sea level rise is a concern. And by having this information at our fingertips, we can portray that across into regional, international forum that it is a concern. Especially with those islands that are barely above sea level.

PSLGM supports a range of critical services including: mapping maritime boundaries; supporting forecast services; supporting emergency response; informing scientific research.

So the Pacific network has been around for 30 years, they just celebrated the 30 year anniversary. The benefit of having good, accurate and consistent long term data is that scientists can be confident that they're using good quality data to provide information for the Pacific communities.

It started off with the sea level stations in early 1990s, where we were able to collect the sea level variations over the years.

And then in early 2000, we incorporated it with the land monitoring station, which is known as the Global Navigation Satellite System Continuous Operating Reference Station. So in short, it’s called GNSS CORS.

So land movement stations were installed within 5 kilometres of these tide stations. The idea being that vertical land movement was considered when assessing sea level.

Vertical land motion is important. It gives us an understanding of the absolute impact of sea level within that area.

To link the vertical land motion from the GNSS reference station to the sea level gauge, we work with our colleagues at SPC, who have surveyors who connect those different sensors.

The key value to Tonga has been the ability and the availability of information to allow Tonga to determine the impacts of sea level rise, the variability of sea level rise, and how that impacts on our coastal areas.

In terms of the recent eruption event here in Tonga, the new tidal gauge very much provided timely information, information that was able to be distributed. I think most important was analysis of how the event impacted on Tonga, particularly with the coastal areas, and the devastation that we suffered. We are using that information in the recovery period.

The scientific community were able to take data from our reference stations to determine the disturbances in the ionosphere that were caused by the volcanic eruption and subsequent tsunami. This research will help improve alerting of natural disasters in the Pacific region.

The PSLGM network also supports a range of daily forecasting products, including the Pacific Ocean portal and the Pacific Tides App.

So one of the most significant achievements over the last five years is building closer relationships with the National Met services in each country.

We developed an infrastructure maintenance program, which has helped to build the skills and capacity of local technicians. So it allows them to carry out their own maintenance on the infrastructure.

So the six monthly infrastructure maintenance program has helped build better relationships among technicians from the Bureau, SPC, GA and the local Met services.

We have common threats of sea level rise, common threats of environmental degradation. It makes very strong sense to share our resources, to be able to address these issues as a region.