When fully implemented, the GCOS Surface Reference Network (GSRN) will deliver sustained surface reference quality observations, with full traceability and fully defined uncertainty, on a global scale on land.
For surface meteorological and terrestrial networks there is currently no global and coordinated reference observing tier. Existing national reference observations are not coordinated internationally, do not focus on a wide range of ECVs, or do not provide coordinated data access. The GCOS Surface Reference Network (GSRN) will fill a gap that has been known to exist for several years, in a cost-effective and coordinated manner.
Reference quality observations are directly traceable to the International System of Units (SI) standards and include full documentation for all components of their uncertainty. Such observations respond to the global need to monitor the changes that occur in the climate and ensure greater confidence in the assessment of future climate change and variability, by reducing or eliminating the remaining uncertainties regarding the causes, effects, magnitude and timing of climate change. A global reference network for surface observations will also support timely political decisions around adaptation and will help to monitor and quantify the effectiveness of internationally agreed mitigation steps. Additionally, benefits would accrue much more immediately, through improved observational understanding and better methods of observation, leading to improvements in numerical weather prediction and disaster and emergency response systems, support to cal/val for satellite observations, climate process understanding and model validation.
A task team (TT-GSRN) was established in November 2020 by the WMO commission for Infrastructure (INFCOM-1). It will be responsible for the initial implementation of the GSRN and will undertake the necessary activities to instigate the network.
As a full implementation of a global surface reference network will take decades, goals for an initial GSRN have been identified in the GSRN 10-year goals. The initial GSRN will provide sustained reference quality observations, with full traceability and fully defined uncertainty, on a global scale of at least the ECVs surface temperature and precipitation to quantify their variability, long-term change and inform on extremes. It will also ensure a free and open access archive of accredited GSRN data products. Operational procedures and practices for knowledge transfer and capacity building will be defined and published and a GSRN affiliated research facility will be established to deliver scientific advances in measurement techniques and to improve knowledge on climate reference data and instrumentation. While in the first phase, the GSRN will concentrate on the delivery of reference observations for temperature and precipitation, a plan for the inclusion of additional ECVs will also be developed and observations of these ECVs will be added as the GSRN evolves in the future.
The success of the implementation of a surface reference network strongly depends on the establishment of a Lead Centre sufficiently resourced and empowered to manage the rollout of such a global network. The Lead Centre is responsible for managing the implementation and operation of GSRN, including the coordination, certification, monitoring and evaluation of observation stations. The GSRN Lead Centre is hosted by the Chinese Meteorological Administration (CMA).