\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[ngerman,english]{babel}



\usepackage{float}








\begin{document}

\title{Combination Strategy for the Geocentric Realisation of Regional Epoch
Reference Frames}



\author[1]{Alexander Kehm}%
\author[1]{Laura Sánchez}%
\author[1]{Mathis Bloßfeld}%
\author[1]{Manuela Seitz}%
\author[1]{Hermann Drewes}%
\author[1]{Detlef Angermann}%
\author[1]{Florian Seitz}%
\affil[1]{Deutsches Geodätisches Forschungsinstitut (DGFI-TUM), Technical University of Munich}%


\vspace{-1em}



  
  \date{June 06, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup





\selectlanguage{english}
\begin{abstract}
For high-resolution regional geodetic applications, the International
Terrestrial Reference Frame (ITRF) is complemented by regional
densifications. These are realised either as multi-year solutions
related to a tectonic plate (e.g., EUREF for Europe) or as epoch
reference frames (ERFs) to capture non-linear geophysical effects like
earthquakes or loading displacements (e.g., SIRGAS for Latin America).
These GNSS-only-based regional frames have in common that their geodetic
datum is aligned with the ITRF datum at a specific epoch. Their origin
is thus geocentric only in a mean sense and does not always coincide
with the instantaneous centre of mass. Here, we present studies on a
direct geocentric realisation of regional ERFs. We propose to realise
the geodetic datum for each epoch by combining global GNSS, SLR and VLBI
networks via measured local ties at co-located sites. An
equally-distributed global GNSS network is used to realise the
orientation via a no-net-rotation constraint and is densified by the
stations of the regional subnetwork. The developed combination and
filtering strategy aims to guarantee a stable datum realisation for each
epoch-wise solution. The effectiveness of our methods is validated
against the current operational realisation of the SIRGAS Latin American
reference frame. Comparing with geophysical loading models relating to
the Earth's centres of mass and figure, we show that the realised
geocentric displacement time series directly reflect seasonal
geophysical processes. Moreover, as the approach does not need to rely
on co-location sites in the region of interest, it is conceptually
transferrable to other global regions.%
\end{abstract}%



\sloppy




\selectlanguage{english}
\FloatBarrier
\end{document}

