EPN Repro2: A reference GNSS tropospheric dataset over Europe

Abstract. The present availability of 18+ years of GNSS data belonging to the EUREF Permanent Network (EPN, http://www.epncb.oma.be/) is a valuable database for the development of a climate data record of GNSS tropospheric products over Europe. This data record can be used as a reference for a variety of scientific applications and has a high potential for monitoring trend and variability in atmospheric water vapour, improving the knowledge of climatic trends of atmospheric water vapour and being useful for regional Numerical Weather Prediction (NWP) reanalyses as well as climate model simulations. In the framework of the EPN-Repro2, the second reprocessing campaign of the EPN, five Analysis Centres homogenously reprocessed the EPN network for the period 1996–2014. A huge effort has been made for providing solutions that are the basis for deriving new coordinates, velocities and troposphere parameters for the entire EPN. The individual contributions are then combined in order to provide the official EPN reprocessed products. This paper is focused on the EPN Repro2 tropospheric product. The combined product is described along with its evaluation against radiosonde data and European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (ERA-Interim) data.

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EPN-Repro2: A reference GNSS tropospheric data set over Europe

Atmospheric Measurement Techniques ◽

10.5194/amt-10-1689-2017 ◽

2017 ◽

Vol 10 (5) ◽

pp. 1689-1705 ◽

Cited By ~ 25

Author(s):

Rosa Pacione ◽

Andrzej Araszkiewicz ◽

Elmar Brockmann ◽

Jan Dousa

Keyword(s):

Climate Model ◽

Weather Prediction ◽

Radiosonde Data ◽

Climate Data ◽

Data Set ◽

Weather Forecasts ◽

Data Record ◽

Individual Contributions ◽

Climate Model Simulations ◽

The Individual

Abstract. The present availability of 18+ years of GNSS data belonging to the EUREF Permanent Network (EPN, http://www.epncb.oma.be/) is a valuable database for the development of a climate data record of GNSS tropospheric products over Europe. This data record can be used as a reference for a variety of scientific applications (e.g. validation of regional numerical weather prediction reanalyses and climate model simulations) and has a high potential for monitoring trends and the variability in atmospheric water vapour. In the framework of the EPN-Repro2, the second reprocessing campaign of the EPN, five Analysis Centres homogenously reprocessed the EPN network for the period 1996–2014. A huge effort has been made to provide solutions that are the basis for deriving new coordinates, velocities and tropospheric parameters for the entire EPN. The individual contributions are then combined to provide the official EPN reprocessed products. This paper is focused on the EPN-Repro2 tropospheric product. The combined product is described along with its evaluation against radiosonde data and European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis (ERA-Interim) data.

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Multi-year GNSS monitoring of atmospheric IWV over Central and South America for climate studies

Annales Geophysicae ◽

10.5194/angeo-34-623-2016 ◽

2016 ◽

Vol 34 (7) ◽

pp. 623-639 ◽

Cited By ~ 13

Author(s):

Clara Eugenia Bianchi ◽

Luciano Pedro Oscar Mendoza ◽

Laura Isabel Fernández ◽

María Paula Natali ◽

Amalia Margarita Meza ◽

...

Keyword(s):

South America ◽

Water Vapour ◽

Weather Prediction ◽

High Rate ◽

Atmospheric Water ◽

Total Delay ◽

Data Set ◽

Atmospheric Water Vapour ◽

Climate Studies

Abstract. Atmospheric water vapour has been acknowledged as an essential climate variable. Weather prediction and hazard assessment systems benefit from real-time observations, whereas long-term records contribute to climate studies. Nowadays, ground-based global navigation satellite system (GNSS) products have become widely employed, complementing satellite observations over the oceans. Although the past decade has seen a significant development of the GNSS infrastructure in Central and South America, its potential for atmospheric water vapour monitoring has not been fully exploited. With this in mind, we have performed a regional, 7-year-long and homogeneous analysis, comprising 136 GNSS tracking stations, obtaining high-rate and continuous observations of column-integrated water vapour and troposphere zenith total delay. As a preliminary application for this data set, we have estimated local water vapour trends, their significance, and their relation with specific climate regimes. We have found evidence of drying at temperate regions in South America, at a rate of about 2 % per decade, while a slow moistening of the troposphere over tropical regions is also weakly suggested by our results. Furthermore, we have assessed the regional performance of the empirical model GPT2w to blindly estimate troposphere delays. The model reproduces the observed mean delays fairly well, including their annual and semi-annual variations. Nevertheless, a long-term evaluation has shown systematical biases, up to 20 mm, probably inherited from the underlying atmospheric reanalysis. Additionally, the complete data set has been made openly available as supplementary material.

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Atmospheric water vapour and its effect on aerosol Extinction at a coastal station – Visakhapatnam

MAUSAM ◽

10.54302/mausam.v44i3.4979 ◽

2022 ◽

Vol 44 (3) ◽

pp. 243-248

Author(s):

K. NIRANJAN ◽

Y. RAMESH BABU

Keyword(s):

Water Vapour ◽

Solar Flux ◽

Radiosonde Data ◽

Aerosol Extinction ◽

Atmospheric Water ◽

Precipitable Water Vapour ◽

Water Vapour Content ◽

Coastal Station ◽

Atmospheric Water Vapour ◽

Flux Measurements

Integrated atmospheric water vapour content. has been evaluated from the spectral optical depths around the PaT band of water vapour by making directly transmitted solar flux measurements at 800, 935 and 1025 nm. The temporal variation of the total precipitable water vapour shows significant seasonal variation with maximum during~ pre-monsoon and monsoon months and minimum during winter months. The integrated content shows a positive correlation with surface humidity parameters and the correlation is better during monsoon months compared to other seasons. The experimentally derived variations of water vapour are compared with the model variations formulated using radiosonde data. The aerosol extinctions derived from the, multi-spectral solar flux measurements in the visible and near IR regions increase with increasing atmospheric water vapour and this increase shows .a seasonal dependence the surface temperature also seems to affect the, aerosol extinction probably through Its effect on the mixing heights.

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Bias adjustment for threshold-based climate indicators

Advances in Science and Research ◽

10.5194/asr-15-107-2018 ◽

2018 ◽

Vol 15 ◽

pp. 107-116

Author(s):

Peter Hoffmann ◽

Christoph Menz ◽

Arne Spekat

Keyword(s):

Climate Model ◽

Heavy Precipitation ◽

Threshold Value ◽

Maximum Temperature ◽

Climate Projections ◽

Climate Data ◽

Bias Adjustment ◽

Climate Indicators ◽

Climate Model Simulations ◽

The Individual

Abstract. A method is presented which applies bias adjustments to climate indicators that are based on fixed thresholds, e.g., the number of hot days with the maximum temperature exceeding 30 ∘C or the number of days with heavy precipitation in exceedance of 20 mm rainfall. The bias adjustment first identifies the percentile of the required threshold value in reference climate data. Then it computes the value of this percentile for the individual historical climate model simulations – here an ensembles of EURO-CORDEX model runs, including dynamical and statistical models. Finally, the climate indicator is re-calculated for each model. The method is applied to climate projections as well, giving further insight into the projected development of the ensemble for extreme conditions. It is assessed that communication to the public and decision makers is improved by expressing these changes in extremes based on absolute values.

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