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        <titl xml:lang="sv">Horisontella atmosfärsgradienter skattade med hjälp av rymdgeodetiska tekniker</titl>
        <parTitl xml:lang="en">On the information content in linear horizontal delay gradients estimated from space geodesy observations</parTitl>
        <IDNo agency="SND">snd1090-1-1.0</IDNo>
        <IDNo agency="DOI">https://doi.org/10.5878/nswt-yr39</IDNo>
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        <producer xml:lang="en" abbr="SND">Swedish National Data Service</producer>
        <producer xml:lang="sv" abbr="SND">Svensk nationell datatjänst</producer>
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      <holdings URI="https://doi.org/10.5878/nswt-yr39">Landing page</holdings>
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      <titlStmt>
        <titl xml:lang="sv">Horisontella atmosfärsgradienter skattade med hjälp av rymdgeodetiska tekniker</titl>
        <parTitl xml:lang="en">On the information content in linear horizontal delay gradients estimated from space geodesy observations</parTitl>
        <IDNo agency="SND">snd1090-1-1.0</IDNo>
        <IDNo agency="DOI">https://doi.org/10.5878/nswt-yr39</IDNo>
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        <AuthEnty xml:lang="en" affiliation="Department of Space, Earth and Environment, Chalmers University of Technology">Elgered, Gunnar</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Institutionen för rymd-, geo- och miljövetenskap, Chalmers tekniska högskola">Elgered, Gunnar</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="Department of Space, Earth and Environment, Chalmers University of Technology">Forkman, Peter</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Institutionen för rymd-, geo- och miljövetenskap, Chalmers tekniska högskola">Forkman, Peter</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="Department of Space, Earth and Environment, Chalmers University of Technology">Haas, Rüdiger</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Institutionen för rymd-, geo- och miljövetenskap, Chalmers tekniska högskola">Haas, Rüdiger</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="Lantmäteriet">Ning, Tong</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Lantmäteriet">Ning, Tong</AuthEnty>
      </rspStmt>
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      <distStmt>
        <distrbtr xml:lang="en" abbr="SND" URI="https://snd.se">Swedish National Data Service</distrbtr>
        <distrbtr xml:lang="sv" abbr="SND" URI="https://snd.se">Svensk nationell datatjänst</distrbtr>
        <distDate xml:lang="en" date="2019-02-22" />
      </distStmt>
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        <version elementVersion="1.0" elementVersionDate="2019-02-22" />
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      <holdings URI="https://doi.org/10.5878/nswt-yr39">Landing page</holdings>
    </citation>
    <stdyInfo>
      <subject>
        <keyword xml:lang="en" vocab="INSPIRE Spatial Data Themes" vocabURI="http://inspire.ec.europa.eu/theme/ac">Atmospheric conditions</keyword>
        <keyword xml:lang="sv" vocab="INSPIRE Spatial Data Themes" vocabURI="http://inspire.ec.europa.eu/theme/ac">Atmosfäriska förhållanden</keyword>
        <keyword xml:lang="en" vocab="INSPIRE Spatial Data Themes" vocabURI="http://inspire.ec.europa.eu/theme/mf">Meteorological geographical features</keyword>
        <keyword xml:lang="sv" vocab="INSPIRE Spatial Data Themes" vocabURI="http://inspire.ec.europa.eu/theme/mf">Geografiska meteorologiska förhållanden</keyword>
        <topcClas xml:lang="en" vocab="INSPIRE topic categories" vocabURI="http://inspire.ec.europa.eu/metadata-codelist/TopicCategory/geoscientificInformation">Geoscientific Information</topcClas>
        <topcClas xml:lang="sv" vocab="INSPIRE topic categories" vocabURI="http://inspire.ec.europa.eu/metadata-codelist/TopicCategory/geoscientificInformation">Geovetenskap</topcClas>
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      <abstract xml:lang="en" contentType="abstract">The data are produced for a scientific article, https://doi.org/10.5194/amt-2018-318, with the following abstract:

We assess the quality of estimated linear horizontal gradients in the atmospheric propagation delay above ground-based stations receiving signals from the Global Positioning System (GPS). Gradients are estimated from 11 years of observations from five stations in Sweden. Comparing these gradients with the corresponding ones from the European Centre for Medium-Range Weather Forecasts (ECMWF) analyses show that GPS gradients confirm known seasonal effects both in the hydrostatic and the wet components. The two GPS stations equipped with microwave absorbing material below the antenna in general show higher correlation coefficients with the ECMWF gradients compared to the other three stations. We also estimated gradients using GPS data from two collocated antenna installations at the Onsala Space Observatory. Correlation coefficients for the east and the north wet gradients from GPS can for specific months reach up to 0.8 when compared to simultaneously estimated wet gradients from microwave radiometry.  The best agreement is obtained when an elevation cutoff angle of 3° is applied in the GPS data processing, in spite of the fact that the radiometer does not observe below 20°. Based on the four years of results we note a strong seasonal dependence in the correlation coefficients, from 0.3 during months with smaller gradients to 0.8 during months with larger gradients, typically during the warmer, and more humid, part of the year. Finally, a case study using a 15-day long continuous Very Long Baseline Interferometry (VLBI) campaign was carried out.
The comparison of the gradients estimated from VLBI and GPS data indicates that a homogeneous and frequent sampling of the sky is a critical parameter.</abstract>
      <abstract xml:lang="sv" contentType="abstract">Datamängden består av atmosfärsmätningar med hjälp av signaler från globala satellitbaserade navigationssystem. Data är insamlade vid fem platser i Sverige, från 2006 till 2016. Speciellt fokus är på Onsala rymdobservatorium där atmosfärsskattningar från två GNSS-stationer jämförs med motsvarnade skattningar gjorda med data från mikrovågsradiometri och långbasinterferomtri (VLBI = Very Long Baseline Interferomtry) under perioden 2013–2016.</abstract>
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        <nation xml:lang="sv" abbr="SE">Sverige</nation>
        <dataKind xml:lang="en">Numeric</dataKind>
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    <dataAccs>
      <useStmt>
        <restrctn xml:lang="en">Access to data through SND. Data are freely accessible.</restrctn>
        <restrctn xml:lang="sv">Åtkomst till data via SND. Data är fritt tillgängliga.</restrctn>
        <conditions elementVersion="info:eu-repo-Access-Terms vocabulary">openAccess</conditions>
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      <relPubl>
        <citation>
          <titlStmt>
            <titl xml:lang="sv">Elgered, G., Ning, T., Forkman, P., and Haas, R.:
On the information content in linear horizontal delay gradients estimated from space geodesy observations,
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2018-318</titl>
            <parTitl xml:lang="en">Elgered, G., Ning, T., Forkman, P., and Haas, R.:
On the information content in linear horizontal delay gradients estimated from space geodesy observations,
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2018-318</parTitl>
          </titlStmt>
          <distStmt>
            <distDate date="2018">2018</distDate>
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        </citation>
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