Monia Negusini - Academia.edu (original) (raw)

Papers by Monia Negusini

Research paper thumbnail of VLBI-derived troposphere parameters during CONT08

Research paper thumbnail of The measurement of the reference point of the VLBI antenna at Ny-Ålesund using GPS

The precise link between different space geodesy techniques (e.g.: GPS, SLR, DORIS or VLBI) is a ... more The precise link between different space geodesy techniques (e.g.: GPS, SLR, DORIS or VLBI) is a fundamental task at any location where more than one technique is available. In the case of a VLBI antenna this task is, in general, quite difficult due to the dimension of the antenna and the fact that the reference point is, in many cases,

Research paper thumbnail of Italy INAF Data Center Report

... The IRA started to store geodetic VLBI databases in 1989, but the databases archived in Bolog... more ... The IRA started to store geodetic VLBI databases in 1989, but the databases archived in Bologna mostly contain data including European antennas from 1987 onward. ... The Internet address of this computer is sarip.ira.inaf.it. ...

Research paper thumbnail of Ground-Based Water Vapor Retrieval in Antarctica: An Assessment

IEEE Transactions on Geoscience and Remote Sensing, 2016

Research paper thumbnail of GPS-derived Precipitable Water Vapour in Antarctica and validation with radiosoundings

ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximate... more ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximately one third or less than that present at mid latitudes. On the Antarctic Plateau, it drops down to less than a few mm. As a consequence, the use of GPS data in sensing the atmosphere can be reliably applied only on coastal areas, were the PWV is large enough to exceed the sensitivity of the method. Radio-soundings (RS) are periodically performed at several coastal Antarctic stations, where permanent GPS equipments are also installed. The sites to be analyzed were selected according to the radiosonde equipment: the Vaisala sensors' readings were corrected specifically with ad hoc models. The co-location of GPS and radio-soundings allows us to validate the PWV content with totally independent techniques. In this investigation we present the results of the analysis of continuous long time series of GPS data acquired at Mawson (MAW1), Casey (CAS1), Davis (DAV1), McMurdo (MCM4) and Mario Zucchelli (TNB1) stations over twelve years (1999-2010). Particularly, at each site, the PWV is determined with GPS data and the same parameter derived from the analysis of the radio-sounding is used for validation. The GPS analysis is optimized for Antarctic data, using specific atmospheric models (e.g. the Vienna Mapping Function) and particular care in the data screening and elimination. The ZHD values are extracted from a grid model provided by the TU Wien (http://ggosatm.hg.tuwien.ac.at/DELAY/GRID) and bilienarly interpolated at the site location. At MZS, surface met parameters are available and used to compute the ZHD which is compared with the corresponding grid-derived ZHD series. We find discrepancies and a seasonal signal that straightforwardly impact the PW time series.

Research paper thumbnail of 2002 Local Geodetic Survey of VLBI and GPS Reference Points and Eccentricity at Medicina (Italy)

Research paper thumbnail of Medicina and Noto VLBI Radiotelescopes: gravitational deformations evaluated with terrestrial laser scanning

Research paper thumbnail of Multi-technique approach for deriving a VLBI signal extra-path variation model induced by gravity: the example of Medicina

Research paper thumbnail of GPS-derived Precipitable Water Vapour in Antarctica and validation with radiosoundings

ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximate... more ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximately one third or less than that present at mid latitudes. On the Antarctic Plateau, it drops down to less than a few mm. As a consequence, the use of GPS data in sensing the atmosphere can be reliably applied only on coastal areas, were the PWV is large enough to exceed the sensitivity of the method. Radio-soundings (RS) are periodically performed at several coastal Antarctic stations, where permanent GPS equipments are also installed. The sites to be analyzed were selected according to the radiosonde equipment: the Vaisala sensors' readings were corrected specifically with ad hoc models. The co-location of GPS and radio-soundings allows us to validate the PWV content with totally independent techniques. In this investigation we present the results of the analysis of continuous long time series of GPS data acquired at Mawson (MAW1), Casey (CAS1), Davis (DAV1), McMurdo (MCM4) and Mario Zucchelli (TNB1) stations over twelve years (1999-2010). Particularly, at each site, the PWV is determined with GPS data and the same parameter derived from the analysis of the radio-sounding is used for validation. The GPS analysis is optimized for Antarctic data, using specific atmospheric models (e.g. the Vienna Mapping Function) and particular care in the data screening and elimination. The ZHD values are extracted from a grid model provided by the TU Wien (http://ggosatm.hg.tuwien.ac.at/DELAY/GRID) and bilienarly interpolated at the site location. At MZS, surface met parameters are available and used to compute the ZHD which is compared with the corresponding grid-derived ZHD series. We find discrepancies and a seasonal signal that straightforwardly impact the PW time series.

Research paper thumbnail of Terra Nova Bay GPS permanent station

Research paper thumbnail of GPS and Radiosonde Derived Precipitable Water Vapour Content and its Relationship with 5 Years of Long-Wave Radiation Measurements at “Mario Zucchelli” Station, Terra Nova Bay, Antarctica

The GPS data set acquired over a six-year period spanning 2000-2005 by the permanent GPS station ... more The GPS data set acquired over a six-year period spanning 2000-2005 by the permanent GPS station TNB1 installed at Mario Zucchelli station is here analyzed, with the aim of retrieving the Precipitable Water (PW) content. Precise calculations and measurements of the mean ...

Research paper thumbnail of Improved geodetic European very-long-baseline interferometry solution using models of antenna gravitational deformation

Annals of Geophysics, 2010

Research paper thumbnail of Multi-technique approach for deriving a VLBI signal extra-path variation model induced by gravity: the example of Medicina

Research paper thumbnail of Tropospheric Parameters Estimated by Geodetic VLBI Data IVS

Research paper thumbnail of Geodetic techniques applied to the study of the Etna volcano area (Italy)

International Journal of Earth Sciences, 2011

Volcanic behaviour of Mt. Etna is due to the complex interaction between both the local and the r... more Volcanic behaviour of Mt. Etna is due to the complex interaction between both the local and the regional stress field involving the eastern Sicily. Eruptions could trigger (be triggered?) during crust extension and/or compression, which are strictly linked with the dynamics of the lower mantle. In this study, very long baseline interferometry (VLBI) space geodesy technique has been used in

Research paper thumbnail of VLBI telescopes' gravitational deformations investigated with terrestrial surveying methods

Research paper thumbnail of Colocation of VLBI reference point and GPS permanent station using rapid static and kinematic GPS

During a one day measurement campaign carried out in 2001 and 2002, we used rapid static and kine... more During a one day measurement campaign carried out in 2001 and 2002, we used rapid static and kinematic GPS techniques in order to determine the reference point of the VLBI antenna situated at the radioastronomical observatory of Medicina. Triangulation and trilateration using high precision total stations have demonstrated millimetre accuracy but can be very time consuming. This latter approach also

Research paper thumbnail of VLBI height corrections due to gravitational deformation of antenna structures

From an analysis of regional European VLBI data we evaluate the impact of a VLBI signal path corr... more From an analysis of regional European VLBI data we evaluate the impact of a VLBI signal path correction model developed to account for gravitational deformations of the antenna structures. The model was derived from a combination of terrestrial surveying methods applied to telescopes at Medicina and Noto in Italy. We find that the model corrections shift the derived height components

Research paper thumbnail of Height biases and scale variations in VLBI networks due to antenna gravitational deformations

The impact of signal path variations (SPVs) caused by antenna gravity deformations on geodetic VL... more The impact of signal path variations (SPVs) caused by antenna gravity deformations on geodetic VLBI results is evaluated for the first time. Elevation-dependent models of SPV for Medicina and Noto (Italy) telescopes were derived from a combination of terrestrial surveying methods to account for gravitational deformations. After applying these models, estimates of the antenna reference point (ARP) positions are shifted

Research paper thumbnail of IVS Pilot Project - Tropospheric Parameters

In April 2002 the IVS (International VLBI Service for Geodesy and Astrometry) set up the IVS Pilo... more In April 2002 the IVS (International VLBI Service for Geodesy and Astrometry) set up the IVS Pilot Project - Tropospheric Parameters and the Institute of Geodesy and Geophysics (IGG), Vienna, was asked to coordinate the project. After a call for participation six IVS Analysis Centers have joined the project and submitted their estimates of tropospheric parameters (wet and total zenith

Research paper thumbnail of VLBI-derived troposphere parameters during CONT08

Research paper thumbnail of The measurement of the reference point of the VLBI antenna at Ny-Ålesund using GPS

The precise link between different space geodesy techniques (e.g.: GPS, SLR, DORIS or VLBI) is a ... more The precise link between different space geodesy techniques (e.g.: GPS, SLR, DORIS or VLBI) is a fundamental task at any location where more than one technique is available. In the case of a VLBI antenna this task is, in general, quite difficult due to the dimension of the antenna and the fact that the reference point is, in many cases,

Research paper thumbnail of Italy INAF Data Center Report

... The IRA started to store geodetic VLBI databases in 1989, but the databases archived in Bolog... more ... The IRA started to store geodetic VLBI databases in 1989, but the databases archived in Bologna mostly contain data including European antennas from 1987 onward. ... The Internet address of this computer is sarip.ira.inaf.it. ...

Research paper thumbnail of Ground-Based Water Vapor Retrieval in Antarctica: An Assessment

IEEE Transactions on Geoscience and Remote Sensing, 2016

Research paper thumbnail of GPS-derived Precipitable Water Vapour in Antarctica and validation with radiosoundings

ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximate... more ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximately one third or less than that present at mid latitudes. On the Antarctic Plateau, it drops down to less than a few mm. As a consequence, the use of GPS data in sensing the atmosphere can be reliably applied only on coastal areas, were the PWV is large enough to exceed the sensitivity of the method. Radio-soundings (RS) are periodically performed at several coastal Antarctic stations, where permanent GPS equipments are also installed. The sites to be analyzed were selected according to the radiosonde equipment: the Vaisala sensors' readings were corrected specifically with ad hoc models. The co-location of GPS and radio-soundings allows us to validate the PWV content with totally independent techniques. In this investigation we present the results of the analysis of continuous long time series of GPS data acquired at Mawson (MAW1), Casey (CAS1), Davis (DAV1), McMurdo (MCM4) and Mario Zucchelli (TNB1) stations over twelve years (1999-2010). Particularly, at each site, the PWV is determined with GPS data and the same parameter derived from the analysis of the radio-sounding is used for validation. The GPS analysis is optimized for Antarctic data, using specific atmospheric models (e.g. the Vienna Mapping Function) and particular care in the data screening and elimination. The ZHD values are extracted from a grid model provided by the TU Wien (http://ggosatm.hg.tuwien.ac.at/DELAY/GRID) and bilienarly interpolated at the site location. At MZS, surface met parameters are available and used to compute the ZHD which is compared with the corresponding grid-derived ZHD series. We find discrepancies and a seasonal signal that straightforwardly impact the PW time series.

Research paper thumbnail of 2002 Local Geodetic Survey of VLBI and GPS Reference Points and Eccentricity at Medicina (Italy)

Research paper thumbnail of Medicina and Noto VLBI Radiotelescopes: gravitational deformations evaluated with terrestrial laser scanning

Research paper thumbnail of Multi-technique approach for deriving a VLBI signal extra-path variation model induced by gravity: the example of Medicina

Research paper thumbnail of GPS-derived Precipitable Water Vapour in Antarctica and validation with radiosoundings

ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximate... more ABSTRACT In Polar regions, the atmospheric precipitable water vapour (PWV) content is approximately one third or less than that present at mid latitudes. On the Antarctic Plateau, it drops down to less than a few mm. As a consequence, the use of GPS data in sensing the atmosphere can be reliably applied only on coastal areas, were the PWV is large enough to exceed the sensitivity of the method. Radio-soundings (RS) are periodically performed at several coastal Antarctic stations, where permanent GPS equipments are also installed. The sites to be analyzed were selected according to the radiosonde equipment: the Vaisala sensors' readings were corrected specifically with ad hoc models. The co-location of GPS and radio-soundings allows us to validate the PWV content with totally independent techniques. In this investigation we present the results of the analysis of continuous long time series of GPS data acquired at Mawson (MAW1), Casey (CAS1), Davis (DAV1), McMurdo (MCM4) and Mario Zucchelli (TNB1) stations over twelve years (1999-2010). Particularly, at each site, the PWV is determined with GPS data and the same parameter derived from the analysis of the radio-sounding is used for validation. The GPS analysis is optimized for Antarctic data, using specific atmospheric models (e.g. the Vienna Mapping Function) and particular care in the data screening and elimination. The ZHD values are extracted from a grid model provided by the TU Wien (http://ggosatm.hg.tuwien.ac.at/DELAY/GRID) and bilienarly interpolated at the site location. At MZS, surface met parameters are available and used to compute the ZHD which is compared with the corresponding grid-derived ZHD series. We find discrepancies and a seasonal signal that straightforwardly impact the PW time series.

Research paper thumbnail of Terra Nova Bay GPS permanent station

Research paper thumbnail of GPS and Radiosonde Derived Precipitable Water Vapour Content and its Relationship with 5 Years of Long-Wave Radiation Measurements at “Mario Zucchelli” Station, Terra Nova Bay, Antarctica

The GPS data set acquired over a six-year period spanning 2000-2005 by the permanent GPS station ... more The GPS data set acquired over a six-year period spanning 2000-2005 by the permanent GPS station TNB1 installed at Mario Zucchelli station is here analyzed, with the aim of retrieving the Precipitable Water (PW) content. Precise calculations and measurements of the mean ...

Research paper thumbnail of Improved geodetic European very-long-baseline interferometry solution using models of antenna gravitational deformation

Annals of Geophysics, 2010

Research paper thumbnail of Multi-technique approach for deriving a VLBI signal extra-path variation model induced by gravity: the example of Medicina

Research paper thumbnail of Tropospheric Parameters Estimated by Geodetic VLBI Data IVS

Research paper thumbnail of Geodetic techniques applied to the study of the Etna volcano area (Italy)

International Journal of Earth Sciences, 2011

Volcanic behaviour of Mt. Etna is due to the complex interaction between both the local and the r... more Volcanic behaviour of Mt. Etna is due to the complex interaction between both the local and the regional stress field involving the eastern Sicily. Eruptions could trigger (be triggered?) during crust extension and/or compression, which are strictly linked with the dynamics of the lower mantle. In this study, very long baseline interferometry (VLBI) space geodesy technique has been used in

Research paper thumbnail of VLBI telescopes' gravitational deformations investigated with terrestrial surveying methods

Research paper thumbnail of Colocation of VLBI reference point and GPS permanent station using rapid static and kinematic GPS

During a one day measurement campaign carried out in 2001 and 2002, we used rapid static and kine... more During a one day measurement campaign carried out in 2001 and 2002, we used rapid static and kinematic GPS techniques in order to determine the reference point of the VLBI antenna situated at the radioastronomical observatory of Medicina. Triangulation and trilateration using high precision total stations have demonstrated millimetre accuracy but can be very time consuming. This latter approach also

Research paper thumbnail of VLBI height corrections due to gravitational deformation of antenna structures

From an analysis of regional European VLBI data we evaluate the impact of a VLBI signal path corr... more From an analysis of regional European VLBI data we evaluate the impact of a VLBI signal path correction model developed to account for gravitational deformations of the antenna structures. The model was derived from a combination of terrestrial surveying methods applied to telescopes at Medicina and Noto in Italy. We find that the model corrections shift the derived height components

Research paper thumbnail of Height biases and scale variations in VLBI networks due to antenna gravitational deformations

The impact of signal path variations (SPVs) caused by antenna gravity deformations on geodetic VL... more The impact of signal path variations (SPVs) caused by antenna gravity deformations on geodetic VLBI results is evaluated for the first time. Elevation-dependent models of SPV for Medicina and Noto (Italy) telescopes were derived from a combination of terrestrial surveying methods to account for gravitational deformations. After applying these models, estimates of the antenna reference point (ARP) positions are shifted

Research paper thumbnail of IVS Pilot Project - Tropospheric Parameters

In April 2002 the IVS (International VLBI Service for Geodesy and Astrometry) set up the IVS Pilo... more In April 2002 the IVS (International VLBI Service for Geodesy and Astrometry) set up the IVS Pilot Project - Tropospheric Parameters and the Institute of Geodesy and Geophysics (IGG), Vienna, was asked to coordinate the project. After a call for participation six IVS Analysis Centers have joined the project and submitted their estimates of tropospheric parameters (wet and total zenith