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A new segmentation method for the homogenisation of GNSS-derived IWV time-series / Annarosa Quarello in Journal of the Royal Statistical Society: Series C Applied Statistics, vol inconnu ([01/01/2021])
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[article]
Titre : A new segmentation method for the homogenisation of GNSS-derived IWV time-series Type de document : Article/Communication Auteurs : Annarosa Quarello, Auteur ; Olivier Bock , Auteur ; Emilie Lebarbier, Auteur
Année de publication : 2021 Projets : VEGA (LEFE/INSU) / Bock, Olivier Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes descripteurs IGN] erreur systématique
[Termes descripteurs IGN] programmation dynamique
[Termes descripteurs IGN] R (langage)
[Termes descripteurs IGN] segmentation
[Termes descripteurs IGN] série temporelle
[Termes descripteurs IGN] teneur intégrée en vapeur d'eau
[Termes descripteurs IGN] varianceRésumé : (auteur) Homogenization is an important and crucial step to improve the usage of observational data for climate analysis. This work is motivated by the analysis of long series of GNSS Integrated Water Vapour (IWV) data which have not yet been used in this context. This paper proposes a novel segmentation method that integrates a periodic bias and a heterogeneous, monthly varying, variance. The method consists in estimating first the variance using a robust estimator and then estimating the segmentation and periodic bias iteratively. This strategy allows for the use of the dynamic programming algorithm that remains the most efficient exact algorithm to estimate the change-point positions. The statistical performance of the method is assessed through numerical experiments. An application to a real data set of 120 global GNSS stations is presented. The method is implemented in the R package GNSSseg that will be available on the CRAN. Numéro de notice : A2021-061 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Autre URL associée : vers HAL Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern En ligne : https://arxiv.org/pdf/2005.04683.pdf Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96617
in Journal of the Royal Statistical Society: Series C Applied Statistics > vol inconnu [01/01/2021][article]Global Climate [in “State of the Climate in 2019"] / A. Ades in Bulletin of the American Meteorological Society, vol 101 n° 8 (August 2020)
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[article]
Titre : Global Climate [in “State of the Climate in 2019"] Type de document : Article/Communication Auteurs : A. Ades, Auteur ; R. Adler, Auteur ; et al., Auteur ; Olivier Bock , Auteur
Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : pp S9 - S128 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Atmosphère
[Termes descripteurs IGN] changement climatique
[Termes descripteurs IGN] circulation atmosphérique
[Termes descripteurs IGN] climat terrestre
[Termes descripteurs IGN] cryosphère
[Termes descripteurs IGN] données météorologiques
[Termes descripteurs IGN] gaz à effet de serre
[Termes descripteurs IGN] humidité de l'air
[Termes descripteurs IGN] humidité du sol
[Termes descripteurs IGN] précipitation
[Termes descripteurs IGN] sécheresse
[Termes descripteurs IGN] température de l'airRésumé : (auteur) [introduction] The assessments and analyses presented in this chapter focus predominantly on the measured differences of climate and weather observables from previous conditions, years, and decades to place 2019 in context. Many of these differences have direct impacts on people, for example, their health and environment, as well as the wider biosphere, but are beyond the scope of these analyses. For the last few State of the Climate reports, an update on the number of warmer-than-average years has held no surprises, and this year is again no different. The year 2019 was among the three warmest years since records began in the mid-to-late 1800s. Only 2016, and for some datasets 2015, were warmer than 2019; all years after 2013 have been warmer than all others back to the mid-1800s. Each decade since 1980 has been successively warmer than the preceding decade, with the most recent (2010–19) being around 0.2°C warmer than the previous (2000–09). This warming of the land and ocean surface is reflected across the globe. For example, lake and permafrost temperatures have increased; glaciers have continued to lose mass, becoming thinner for the 32nd consecutive year, with the majority also becoming shorter during 2019. The period during which Northern Hemisphere (NH) lakes were covered in ice was seven days shorter than the 1981–2010 long-term average, based on in situ phenological records. There were fewer cool extremes and more warm extremes on land; regions including Europe, Japan, Pakistan, and India all experienced heat waves. More strong than moderate marine heat waves were recorded for the sixth consecutive year. And in Australia (discussed in more detail in section 7h4), moisture deficits and prolonged high temperatures led to severe impacts during late austral spring and summer, including devastating wildfires. Smoke from these wildfires was detected across large parts of the Southern Hemisphere (SH). [...] Numéro de notice : A2020-798 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1175/BAMS-D-20-0104.1 date de publication en ligne : 12/08/2020 En ligne : https://doi.org/10.1175/BAMS-D-20-0104.1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96582
in Bulletin of the American Meteorological Society > vol 101 n° 8 (August 2020) . - pp S9 - S128[article]A breakpoint detection in the mean model with heterogeneous variance on fixed time-intervals / Olivier Bock in Statistics and Computing, vol 29 n° 1 (February 2020)
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[article]
Titre : A breakpoint detection in the mean model with heterogeneous variance on fixed time-intervals Type de document : Article/Communication Auteurs : Olivier Bock , Auteur ; Xavier Collilieux
, Auteur ; François Guillamon, Auteur ; Emilie Lebarbier, Auteur ; Claire Pascal, Auteur
Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : pp 1 - 13 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes descripteurs IGN] analyse de variance
[Termes descripteurs IGN] données GNSS
[Termes descripteurs IGN] inférence statistique
[Termes descripteurs IGN] méthode robuste
[Termes descripteurs IGN] points de rupture
[Termes descripteurs IGN] processus gaussien
[Termes descripteurs IGN] segmentation
[Termes descripteurs IGN] série temporelle
[Termes descripteurs IGN] variabilitéRésumé : (Auteur) This work is motivated by an application for the homogenization of global navigation satellite system (GNSS)-derived integrated water vapour series. Indeed, these series are affected by abrupt changes due to equipment changes or environmental effects. The detection and correction of the series from these changes are a crucial step before any use for climate studies. In addition to these abrupt changes, it has been observed in the series a non-stationary of the variability. We propose in this paper a new segmentation model that is a breakpoint detection in the mean model of a Gaussian process with heterogeneous variance on known time intervals. In this segmentation case, the dynamic programming algorithm used classically to infer the breakpoints cannot be applied anymore. We propose a procedure in two steps: we first estimate robustly the variances and then apply the classical inference by plugging these estimators. The performance of our proposed procedure is assessed through simulation experiments. An application to real GNSS data is presented. Numéro de notice : A2020-368 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : MATHEMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s11222-019-09853-5 date de publication en ligne : 03/05/2019 En ligne : https://doi.org/10.1007/s11222-019-09853-5 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92571
in Statistics and Computing > vol 29 n° 1 (February 2020) . - pp 1 - 13[article]Advanced GNSS tropospheric products for monitoring severe weather events and climate, ch. 5. Use of GNSS Tropospheric Products for Climate Monitoring (Working Group 3) / Olivier Bock (2020)
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contenu dans Advanced GNSS tropospheric products for monitoring severe weather events and climate / Jonathan Jones (2020)
Titre de série : Advanced GNSS tropospheric products for monitoring severe weather events and climate, ch. 5 Titre : Use of GNSS Tropospheric Products for Climate Monitoring (Working Group 3) Type de document : Chapitre/Contribution Auteurs : Olivier Bock , Auteur ; Rosa Pacione, Auteur ; F. Ahmed, Auteur ; A. Araszkiewicz, Auteur ; et al., Auteur ; Samuel Nahmani
, Auteur ; Paul Rebischung
, Auteur ; Pascal Willis
, Auteur
Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2020 Projets : GNSS4SWEC / Importance : pp 267 - 402 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes descripteurs IGN] données GNSS
[Termes descripteurs IGN] format SINEX
[Termes descripteurs IGN] propagation troposphérique
[Termes descripteurs IGN] retard troposphérique zénithal
[Termes descripteurs IGN] série temporelle
[Termes descripteurs IGN] surveillance météorologique
[Termes descripteurs IGN] teneur intégrée en vapeur d'eauRésumé : (Auteur) There has been growing interest in recent years in the use of homogeneously reprocessed ground-based GNSS, VLBI, and DORIS measurements for climate applications. Existing datasets are reviewed and the sensitivity of tropospheric estimates to the processing details is discussed. The uncertainty in the derived IWV estimates and linear trends is around 1 kg m−2 RMS and ± 0.3 kg m−2 per decade, respectively. Standardized methods for ZTD outlier detection and IWV conversion are proposed. The homogeneity of final time series is limited however by changes in the stations equipment and environment. Various homogenization algorithms have been evaluated based on a synthetic benchmark dataset. The uncertainty of trends estimated from the homogenized times series is estimated to ±0.5 kg m−2 per decade. Reprocessed GNSS IWV data are analysed along with satellites data, reanalyses and global and regional climate model simulations. A selection of global and regional reprocessed GNSS datasets and ERA-interim reanalysis are made available through the GOP-TropDB tropospheric database and online service. A new tropo SINEX format, providing new features and simplifications, was developed and it is going to be adopted by all the IAG services. Numéro de notice : H2020-001 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Chapître / contribution nature-HAL : ChOuvrScient DOI : 10.1007/978-3-030-13901-8_5 date de publication en ligne : 14/09/2019 En ligne : https://doi.org/10.1007/978-3-030-13901-8_5 Format de la ressource électronique : URL chapitre Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94504 Advanced GNSS tropospheric products for monitoring severe weather events and climate / Jonathan Jones (2020)
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Titre : Advanced GNSS tropospheric products for monitoring severe weather events and climate : COST action ES1206 final action dissemination report Type de document : Actes de congrès Auteurs : Jonathan Jones, Editeur scientifique ; Guergana Guerova, Editeur scientifique ; Jan Douša, Editeur scientifique ; Galina Dick, Editeur scientifique ; Siebren de Haan, Editeur scientifique ; Eric Pottiaux, Editeur scientifique ; Olivier Bock , Editeur scientifique ; Rosa Pacione, Editeur scientifique ; Roeland Van Malderen, Editeur scientifique
Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2020 Projets : GNSS4SWEC / Importance : 563 p. ISBN/ISSN/EAN : 978-3-030-13901-8 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes descripteurs IGN] changement climatique
[Termes descripteurs IGN] climat terrestre
[Termes descripteurs IGN] données GNSS
[Termes descripteurs IGN] données météorologiques
[Termes descripteurs IGN] positionnement par GNSS
[Termes descripteurs IGN] propagation troposphérique
[Termes descripteurs IGN] surveillance météorologique
[Termes descripteurs IGN] vapeur d'eauRésumé : (Editeur) [Introduction] The book (COST Action Final report) summarises the proceedings from COST Action ES1206. COST Action ES1206, Advanced GNSS Tropospheric Products for Severe Weather Events and Climate (GNSS4SWEC), was a 4-year project, running from 2013 to 2017, which coordinated new and improved capabilities from concurrent developments in GNSS, meteorological and climate communities. For the first time, the synergy of multi-GNSS constellations was used to develop new, more advanced tropospheric products, exploiting the full potential of multi-GNSS on a wide range of temporal and spatial scales - from real-time products monitoring and forecasting severe weather, to the highest quality post-processed products suitable for climate research. The Action also promoted the use of meteorological data as an input to real-time GNSS positioning, navigation, and timing services and has stimulated knowledge and data transfer throughout Europe and beyond. Note de contenu : - Front Matter
- General Background
- Advanced GNSS Processing Techniques (Working Group 1)
- Use of GNSS Tropospheric Products for High-Resolution, Rapid-Update NWP and Severe Weather Forecasting (Working Group 2)
- Use of GNSS Tropospheric Products for Climate Monitoring (Working Group 3)
- National Status Reports
- STSM Reports
- Back MatterNuméro de notice : 26248 Affiliation des auteurs : Géodésie+Ext (mi2018-2019) Thématique : POSITIONNEMENT Nature : Actes nature-HAL : DirectOuvrColl/Actes DOI : 10.1007/978-3-030-13901-8 date de publication en ligne : 14/09/2019 En ligne : https://doi.org/10.1007/978-3-030-13901-8 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94503 IWV retrieval from ground and shipborne GPS receivers during NAWDEX [diaporama] / Pierre Bosser (2020)
PermalinkIWV retrieval from shipborne GPS receiver on hydrographic ship Borda [diaporama] / Olivier Bock (2020)
PermalinkA new segmentation method for the homogenisation of GNSS-derived IWV time-series / Annarosa Quarello (2020)
PermalinkConsistency and representativeness of integrated water vapour from ground-based GPS observations and ERA-Interim reanalysis / Olivier Bock in Atmospheric chemistry and physics, vol 19 n° 14 (July 2019)
PermalinkSensitivity of GPS tropospheric estimates to mesoscale convective systems in West Africa / Samuel Nahmani in Atmospheric chemistry and physics, vol 19 n° 14 (July 2019)
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PermalinkThe AROME-WMED reanalyses of the first special observation period of the Hydrological cycle in the Mediterranean experiment (HyMeX) / Nadia Fourrié in Geoscientific Model Development, vol 12 n° 7 (July 2019)
PermalinkImpact of humidity biases on light precipitation occurrence: observations versus simulations / Sophie Bastin in Atmospheric chemistry and physics, vol 19 n° 3 (February 2019)
PermalinkGlobal IWV trends and variability in atmospheric reanalyses and GPS observations / Ana-Claudia Bernardes Parracho in Atmospheric chemistry and physics, vol 18 n° 22 ([01/11/2018])
PermalinkMulti‐scale observations of atmospheric moisture variability in relation to heavy precipitating systems in the northwestern Mediterranean during HyMeX IOP12 / Samiro Khodayar in Quarterly Journal of the Royal Meteorological Society, vol 144 n° 717 (October 2018 Part B)
PermalinkComparison of total water vapour content in the Arctic derived from GNSS, AIRS, MODIS and SCIAMACHY / Dunya Alraddawi in Atmospheric measurement techniques, vol 11 n° 5 (May 2018)
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