Home > Articles > Press Releases > 2022 > NEA and SLA sign MOU to share Global Navigation Satellite System (GNSS)-derived Moisture Data for Weather Monitoring Application

NEA and SLA sign MOU to share Global Navigation Satellite System (GNSS)-derived Moisture Data for Weather Monitoring Application

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The National Environment Agency (NEA) and the Singapore Land Authority (SLA) have signed a Memorandum of Understanding (MOU) to develop the use of Global Navigation Satellite System (GNSS) data obtained from SLA’s Singapore Satellite Reference Network (SiReNT) to enable NEA to better monitor island-wide atmospheric moisture. The five-year collaboration is aimed at benefitting Singapore with additional data for weather monitoring, as well as facilitating exploratory studies for weather forecasting.


2          Meteorological observations are vital for forecasting the weather, monitoring the climate, and producing timely warnings of hazardous weather events. Meteorological Service Singapore (MSS) routinely collects a range of observational data such as temperature, wind, and moisture from ground-based and airborne sensors. At MSS’ Upper Air Observatory (UAO), sensors attached to a weather balloon are routinely released twice a day to obtain measurements of these weather elements at different heights of the atmosphere. In 2019, MSS installed a GNSS reference station at UAO to derive continuous estimates of moisture in a column of the atmosphere[1], known as the integrated precipitable water vapour, to supplement the sounding data obtained from the weather balloon.


3          Under the MOU, MSS’s GNSS station will be integrated into SiReNT, and enable MSS to obtain islandwide, continuous and near real-time atmospheric moisture readings. This non-conventional moisture data will augment MSS’s existing observation network data, providing higher resolution and more frequent observation data, which allows for investigative studies into potential applications for weather forecasting (refer to Annex A for an infographic of the GNSS moisture data collection process).


4          The collaboration will also expand SLA’s SiReNT station network, which currently comprises nine reference stations spread across Singapore. With the addition of NEA’s GNSS base receiver station at UAO that will be incorporated into SiReNT, together with two upcoming additional coastal SiReNT reference stations[2], the network will be expanded to 12 stations with additional receivable data. The SiReNT system can correct positional errors in GNSS signals and produce precise positioning data of up to 3 cm in accuracy. The SiReNT technology supports innovation in diverse industries such as autonomous vehicles, construction automation and logistics, and monitoring of land height and sea-level changes in Singapore. The expansion of stations by the end of 2022 will further improve stability to services and applications in various key industries currently supported by SiReNT. It can also be further leveraged for novel uses in climate-related scientific studies (refer to Annex B for a background of SLA’s SiReNT station network).


5          Mr Luke Goh, CEO of NEA, said, “The collaboration between NEA and SLA highlights our commitment to achieve synergies and tap on enablers across the public sector. This partnership provides a platform for NEA to utilise SLA’s expertise in GNSS data collection and processing, enabling NEA to explore non-traditional methods to enhance our weather monitoring and forecasting capabilities.


6          Mr Colin Low, CEO of SLA said, “This collaboration with NEA is part of SLA’s continuous effort to work with parties from both private and public sector to unlock diverse uses for SiReNT and SLA’s many geospatial products. We believe that by pooling expertise from various parties we can spark more innovation and uncover practicable solutions that can benefit Singapore and our industries. We are excited to work with NEA to study the novel use of SiReNT data for enhanced weather monitoring and investigative studies in weather forecasting and climate change. The many experiences shared and gained from this collaboration will be a building block for future innovations in this field." 

Issued by

National Environment Agency

Singapore Land Authority

2 August 2022

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[1] The slowing down of GNSS signals when travelling through a moist atmosphere can be estimated and used to derive the amount of moisture between the satellite and ground receiver.

[2] NTU Singapore and the Singapore Land Authority collaborate to use satellite date for environment research.

Annex A


Infographic on Understanding the Global Navigation Satellite System (GNSS) Moisture Data Collection Process


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Annex B


Background of the Satellite Reference Network (SiReNT)


Developed by the Singapore Land Authority (SLA) in 2006, the Singapore Satellite Positioning Reference Network (SiReNT) is a national reference network infrastructure that supports real-time high precision positioning, navigation, and monitoring of up to 3cm. The technology is used by Government agencies and private companies in applications where precise positioning is required. This includes the development and operation of self-mobility platforms, construction automation and high accuracy mapping.


2          More information on SiReNT can be found on https://app.sla.gov.sg/sirent/.


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Image 1: The GNSS Reference Station on Sultan Shoal (SSTS)

Photo credit: Singapore Land Authority (SLA)



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Image 2: Locations of SiReNT GNSS Reference Stations. The name of the new NEA station at Kim Chuan is SMS1.

Photo credit: Singapore Land Authority (SLA)

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Image 3: Mr Luke, Goh Chief Executive, National Environment Agency (NEA) (second from left) and Mr Colin Low, CEO of Singapore Land Authority (SLA) (second from right) signed the Memorandum of Understanding to share Global Navigation Satellite System (GNSS)-derived moisture data for weather monitoring application at the World Cities Summit 2022. The signing was witnessed by Ms Koh Li-Na, Assistant Chief Executive, NEA (first from left) and Mr Bryan Chew, Assistant Chief Executive, SLA (first from right).

Photo credit: Singapore Land Authority (SLA)