Quality Management Framework for Climate Datasets

Data from a variety of research programmes are increasingly used by policy makers, researchers, and private sectors to make data-driven decisions related to climate change and variability. Climate services are emerging as the link to narrow the gap between climate science and downstream users. The Global Framework for Climate Services (GFCS) of the World Meteorological Organization (WMO) offers an umbrella for the development of climate services and has identified the quality assessment, along with its use in user guidance, as a key aspect of the service provision. This offers an extra stimulus for discussing what type of quality information to focus on and how to present it to downstream users. Quality has become an important keyword for those working on data in both the private and public sectors and significant resources are now devoted to quality management of processes and products. Quality management guarantees reliability and usability of the product served, it is a key element to build trust between consumers and suppliers. Untrustworthy data could lead to a negative economic impact at best and a safety hazard at worst. In a progressive commitment to establish this relation of trust, as well as providing sufficient guidance for users, the Copernicus Climate Change Service (C3S) has made significant investments in the development of an Evaluation and Quality Control (EQC) function. This function offers a homogeneous user-driven service for the quality of the C3S Climate Data Store (CDS). Here we focus on the EQC component targeting the assessment of the CDS datasets, which include satellite and in-situ observations, reanalysis, climate projections, and seasonal forecasts. The EQC function is characterised by a two-tier review system designed to guarantee the quality of the dataset information. While the need of assessing the quality of climate data is well recognised, the methodologies, the metrics, the evaluation framework, and how to present all this information to the users have never been developed before in an operational service, encompassing all the main climate dataset categories. Building the underlying technical solutions poses unprecedented challenges and makes the C3S EQC approach unique. This paper describes the development and the implementation of the operational EQC function providing an overarching quality management service for the whole CDS data.This study is based on work carried out in the C3S_512 contract funded by Copernicus Programme and operated by ECMWF on behalf of the European Commission (Service Contract number: ECMWF/COPERNICUS720187C3S_512_BSC). We would like to acknowledge the work of colleagues from several European institutions, the data providers and C3S, who contributed to the development of the EQC framework as well as to the QAR production. We would also like to acknowledge the focus group users, who took time to review and provide valuable feedback on the QARs, QATs, minimum requirements and the CDS quality assessment tab. The authors are grateful to the anonymous reviewers for their constructive comments that have helped for the improvement of this paper.Peer Reviewed"Article signat per 23 autors/es: Carlo Lacagnina , Francisco Doblas-Reyes, Gilles Larnicol, Carlo Buontempo, André Obregón, Montserrat Costa-Surós, Daniel San-Martín, Pierre-Antoine Bretonnière, Suraj D. Polade, Vanya Romanova, Davide Putero, Federico Serva, Alba Llabrés-Brustenga, Antonio Pérez, Davide Cavaliere, Olivier Membrive, Christian Steger, Núria Pérez-Zanón, Paolo Cristofanelli, Fabio Madonna, Marco Rosoldi, Aku Riihelä, Markel García Díez"Postprint (published version

Call to action for global access to and harmonization of quality information of individual earth science datasets

Knowledge about the quality of data and metadata is important to support informed decisions on the (re)use of individual datasets and is an essential part of the ecosystem that supports open science. Quality assessments reflect the reliability and usability of data. They need to be consistently curated, fully traceable, and adequately documented, as these are crucial for sound decision-and policy-making efforts that rely on data. Quality assessments also need to be consistently represented and readily integrated across systems and tools to allow for improved sharing of information on quality at the dataset level for individual quality attribute or dimension. Although the need for assessing the quality of data and associated information is well recognized, methodologies for an evaluation framework and presentation of resultant quality information to end users may not have been comprehensively addressed within and across disciplines. Global interdisciplinary domain experts have come together to systematically explore needs, challenges and impacts of consistently curating and representing quality information through the entire lifecycle of a dataset. This paper describes the findings of that effort, argues the importance of sharing dataset quality information, calls for community action to develop practical guidelines, and outlines community recommendations for developing such guidelines. Practical guidelines will allow for global access to and harmonization of quality information at the level of individual Earth science datasets, which in turn will support open science

Call to action for global access to and harmonization of quality information of individual earth science datasets

Knowledge about the quality of data and metadata is important to support informed decisions on the (re)use of individual datasets and is an essential part of the ecosystem that supports open science. Quality assessments reflect the reliability and usability of data. They need to be consistently curated, fully traceable, and adequately documented, as these are crucial for sound decision- and policy-making efforts that rely on data. Quality assessments also need to be consistently represented and readily integrated across systems and tools to allow for improved sharing of information on quality at the dataset level for individual quality attribute or dimension. Although the need for assessing the quality of data and associated information is well recognized, methodologies for an evaluation framework and presentation of resultant quality information to end users may not have been comprehensively addressed within and across disciplines. Global interdisciplinary domain experts have come together to systematically explore needs, challenges and impacts of consistently curating and representing quality information through the entire lifecycle of a dataset. This paper describes the findings of that effort, argues the importance of sharing dataset quality information, calls for community action to develop practical guidelines, and outlines community recommendations for developing such guidelines. Practical guidelines will allow for global access to and harmonization of quality information at the level of individual Earth science datasets, which in turn will support open science

Call to action for global access to and harmonization of quality information of individual earth science datasets

Knowledge about the quality of data and metadata is important to support informed decisions on the (re)use of individual datasets and is an essential part of the ecosystem that supports open science. Quality assessments reflect the reliability and usability of data. They need to be consistently curated, fully traceable, and adequately documented, as these are crucial for sound decision-and policy-making efforts that rely on data. Quality assessments also need to be consistently represented and readily integrated across systems and tools to allow for improved sharing of information on quality at the dataset level for individual quality attribute or dimension. Although the need for assessing the quality of data and associated information is well recognized, methodologies for an evaluation framework and presentation of resultant quality information to end users may not have been comprehensively addressed within and across disciplines. Global interdisciplinary domain experts have come together to systematically explore needs, challenges and impacts of consistently curating and representing quality information through the entire lifecycle of a dataset. This paper describes the findings of that effort, argues the importance of sharing dataset quality information, calls for community action to develop practical guidelines, and outlines community recommendations for developing such guidelines. Practical guidelines will allow for global access to and harmonization of quality information at the level of individual Earth science datasets, which in turn will support open science

Sub-surface small scale eddy dynamics from multi-sensor observations and modeling

The study of mesoscale and submesoscale [hereafter (sub)mesoscale] hydrodynamic features is essential for understanding thermal and biogeochemical exchanges between coastal areas and the open ocean. In this context, a glider mission was conducted in August 2008, closely co-located and almost simultaneously launched with a JASON 2 altimetric pass, to fully characterize the currents associated with regional (sub)mesoscale processes regularly observed to the north of Mallorca (Mediterranean Sea). A synoptic view from satellite remote-sensing fields, before and during the glider mission, provided a descriptive picture of the main surface dynamics at the Balearic Basin scale. To quantify the absolute surface geostrophic currents, the coastal altimetry-derived current computation was improved and cross-compared with its equivalent derived from glider measurements. Model simulations were then validated both qualitatively and statistically with the multi-sensor observations. The combined use of modeling and multi-sensor observational data reveals the baroclinic structure of the Balearic Current and the Northern Current and a small-scale anticyclonic eddy observed northeast of the Mallorca coast (current ∼ 15 cm/s, 180 m deep). This mesoscale structure, partially intercepted by the glider and along-track altimetric measurements, is marked by relatively strong salinity gradients and not, as is more typical, temperature gradients. Finally, the use of the validated model simulation also shows that the geostrophic component of this small-scale eddy is controlled by sub-surface salinity gradients. We hypothesize that this structure contains recently modified Atlantic water arriving from the strait of Ibiza due to a northerly wind, which strengthens the northward geostrophic circulation.This work was partially conducted during a CNES Postdoctoral Fellowship and supported by PERSEUS FP7-OCEAN-2011 (GA 287600) and the European Commission MyOcean Project (SPA.2007.1.1.01 – development of upgrade capabilities for existing GMES fast-track services and related operational services; Grant Agreement 218812-1-FP7-SPACE 2007-1)Peer Reviewe

Analyse de la variabilité de surface en Méditerranée à partir des données altimétriques et comparaison aux simulations MERCATOR et MOG2D

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Vertical motion analysis through combined model, satellite and in situ data. Preliminary results of the MESCLA project

Vertical motion associated with mesoscale and sub-mesoscale oceanic features is of fundamental importance for the exchanges of heat, fresh water and biogeochemical tracers between the surface and the ocean interior. Unfortunately, direct measurements of the vertical velocity are difficult to obtain for usual values (order 10’s m/day). Various indirect methodologies have thus been proposed to estimate vertical velocity from observed density and geostrophic velocity fields. The most used technique is based on the solution of the quasi-geostrophic (QG) Omega equation.Peer Reviewe

A case of an intense anticyclonic eddy in the Balearic Sea (western Mediterranean)

Sea surface topography from TOPEX/Poseidon and ERS satellites, SST images derived from advanced very high resolution radiometer (AVHRR) sensors, and conductivity-temperature-depth (CTD) data collected during an oceanographic survey are examined to investigate an intense mesoscale anticyclonic eddy observed at the northern boundary of the Balearic Sea (western Mediterranean). This eddy, which constitutes the strongest signal detected in the Baleanric basin since altimetric data are available, appeared in September 1998 to the northwest of Menorca Island and remained almost in the same location until its disappearance in March 1999. The paper focuses mainly on identifying the conditions that led to the eddy formation and on the description of its evolution and sudden disappearance. Derived variables such as geostrophic velocity or vorticity are computed to complement the hydrographic and dynamical information provided by observed variables. Also, meteorological data are examined related to the main hypothesis made for the origin of the eddy.Ananda Pascual holds a doctoral fellowship from the Universitat de les Illes Balears. Bruno Buongiorno Nardelli activity has been funded by ARS‐00‐21 contract of the Agenzia Spaziale Italiana.The oceanographic cruise Hivern‐99 was funded by the Spanish CICYT project, MAR98‐0932.Peer Reviewe

Improved description of the ocean mesoscale variability by combining four satellite altimeters

Data from four satellite altimeters are combined with the aim of improving the representation of the mesoscale variability in the Global Ocean. All missions [Jason-1, ERS-2/ENVISAT, Topex/Poseidon interleaved with Jason-1, and Geosat Follow-On] are cross-calibrated previously to produce weekly gridded maps. In areas of intense variability, the rms differences between a classical configuration of two altimeters and the scenario merging four missions can reach 10 cm and 400 cm2/s2 in SLA and EKE, respectively, which represents an important percentage of the signal variance. A comparison with surface drifters shows that the four altimeter scenario improves the recovery of mesoscale structures that were not properly sampled with Jason-1 + ERS-2/ENVISAT. Finally, the consistency between altimetric and tide gauge data is improved by about 25% when coastal sea level is estimated with 4 satellites compared to the results obtained with 2 altimeters. Copyright 2006 by the American Geophysical Union.Peer Reviewe