PUMA publications for /user/geoinst/Gravityhttps://puma.ub.uni-stuttgart.de/user/geoinst/GravityPUMA RSS feed for /user/geoinst/Gravity2024-03-28T15:48:56+01:00Introducing modified total storage deficit index (MTSDI) for drought monitoring using GRACE observationshttps://puma.ub.uni-stuttgart.de/bibtex/2cbf193e450f98938e866d5b757a5ccf0/geoinstgeoinst2019-08-13T14:35:05+02:00Climate and signals,Markazi climate decomposition Gravity Recovery basin,Signal from:tourian Experiment,Large-scale <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Seyed Mohammad Hosseini-Moghari" itemprop="url" href="/person/1b2d26817a6dbb0209cef9826ce17162d/author/0"><span itemprop="name">S. Hosseini-Moghari</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Shahab Araghinejad" itemprop="url" href="/person/1b2d26817a6dbb0209cef9826ce17162d/author/1"><span itemprop="name">S. Araghinejad</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Kumars Ebrahimi" itemprop="url" href="/person/1b2d26817a6dbb0209cef9826ce17162d/author/2"><span itemprop="name">K. Ebrahimi</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Mohammad J. Tourian" itemprop="url" href="/person/1b2d26817a6dbb0209cef9826ce17162d/author/3"><span itemprop="name">M. Tourian</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/PublicationIssue" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="journal">Ecological Indicators</span>, </em> </span>(<em><span>June 2019<meta content="June 2019" itemprop="datePublished"/></span></em>)</span>Tue Aug 13 14:35:05 CEST 2019Ecological Indicatorsjun465--475{Introducing modified total storage deficit index (MTSDI) for drought monitoring using GRACE observations}1012019Climate and signals,Markazi climate decomposition Gravity Recovery basin,Signal from:tourian Experiment,Large-scale Although total storage deficit index (TSDI) is a well-known GRACE-based drought index, it is not efficient for the basins with high consumption because water harvesting in these areas affect GRACE signal. To overcome this limitation, the modified total storage deficit index (MTSDI) is introduced in this paper. To develop MTSDI, residuals of the signal were used instead of total signal. The proposed approach was applied to monitor drought in the Markazi Basin, Iran, during 2002–2016. Based on the obtained results, TSDI detected a moderate drought event in 2012 and a long-term severe drought from 2013 to 2016, which is not compatible with the recorded results of standardized precipitation index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI). Meanwhile MTSDI identified two drought events in 2008–09 and 2010–11 that coincided with droughts detected using SPI and SPEI. Results revealed that MTSDI is highly correlated with SPI and SPEI at a 12 month-scale, showing a correlation coefficient of 0.75 and 0.62, respectively. On the other hand, the coefficient of correlation between TSDI and SPI12 was 0.42 and between TSDI and SPEI12 was 0.26. A pixel-by-pixel analysis showed MTSDI and SPI/SPEI had a significant correlation in most areas of the basin. Further, the investigation of droughts in Markazi Basin revealed that dry years coincide with the occurrence of strong La Ni{\~{n}}a events. Overall, the results indicated a good potential of GRACE observations for developing a drought monitoring system, which its performance can be enhanced with respect to large-scale climate signals.A posteriori de-aliasing of ocean tide error in future double-pair satellite gravity missionshttps://puma.ub.uni-stuttgart.de/bibtex/2b8209142120cda91a5ef5a3e94846699/geoinstgeoinst2019-08-13T14:07:42+02:00mission,Ocean De-aliasing,Future gravity tides,Satellite from:tourian <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="W. Liu" itemprop="url" href="/person/1304515e4d3007d2dcf93d5756e093659/author/0"><span itemprop="name">W. Liu</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="N. Sneeuw" itemprop="url" href="/person/1304515e4d3007d2dcf93d5756e093659/author/1"><span itemprop="name">N. Sneeuw</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="S. Iran Pour" itemprop="url" href="/person/1304515e4d3007d2dcf93d5756e093659/author/2"><span itemprop="name">S. Iran Pour</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="M.J. Tourian" itemprop="url" href="/person/1304515e4d3007d2dcf93d5756e093659/author/3"><span itemprop="name">M. Tourian</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="T. Reubelt" itemprop="url" href="/person/1304515e4d3007d2dcf93d5756e093659/author/4"><span itemprop="name">T. Reubelt</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/Book" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="name">International Association of Geodesy Symposia</span>, </em></span><em> 147, </em>(<em><span>2018<meta content="2018" itemprop="datePublished"/></span></em>)</span>Tue Aug 13 14:07:42 CEST 2019International Association of Geodesy Symposia{A posteriori de-aliasing of ocean tide error in future double-pair satellite gravity missions}1472018mission,Ocean De-aliasing,Future gravity tides,Satellite from:tourian {\textcopyright} Springer International Publishing Switzerland 2016. Ocean tides cause notable aliasing errors in the gravity field from single pair space-borne gravimetry missions like GRACE. Several studies into future gravity missions have shown that constellations with two or more GRACE-like tandems lead to a significant reduction of aliasing error from all kinds of high-frequency signal sources. Despite such reduction, tidal aliasing will remain an error source. We here investigate the efficiency of tidal error de-aliasing in the post-processing mode for such future double-pair missions. To that purpose, we analyze how a certain satellite mission samples each tidal constituent. Given the repeat orbit patterns and the observation time span, we examine and model the alias periods and amplitudes constituent by constituent based on data-driven analysis. Results show that a double-pair formation has indeed better de-aliasing properties than a single-pair formation in terms of distribution and amplitude of ocean tide aliasing error. After least-squares (LS) spectral estimation of the tidal aliases at the derived alias periods, the aliasing error is reduced significantly.GOCE Long-Wavelength Gravity Field Recovery from 1s-Sampled Kinematic Orbits Using the Acceleration Approachhttps://puma.ub.uni-stuttgart.de/bibtex/21d148ccdd30076bbef14d9f3f248288e/geoinstgeoinst2018-06-25T10:22:24+02:00orbits; field; data GOCE; tracking; orbit satellite-to-satellite kinematic variances; weighting from:mantoni gravity <span data-person-type="author" class="authorEditorList "><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Tilo Reubelt" itemprop="url" href="/person/14e9ae2ca88fa663e5b053ecdb384388a/author/0"><span itemprop="name">T. Reubelt</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Oliver Baur" itemprop="url" href="/person/14e9ae2ca88fa663e5b053ecdb384388a/author/1"><span itemprop="name">O. Baur</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Matthias Weigelt" itemprop="url" href="/person/14e9ae2ca88fa663e5b053ecdb384388a/author/2"><span itemprop="name">M. Weigelt</span></a></span>, </span><span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Matthias Roth" itemprop="url" href="/person/14e9ae2ca88fa663e5b053ecdb384388a/author/3"><span itemprop="name">M. Roth</span></a></span>, </span> and <span><span itemtype="http://schema.org/Person" itemscope="itemscope" itemprop="author"><a title="Nico Sneeuw" itemprop="url" href="/person/14e9ae2ca88fa663e5b053ecdb384388a/author/4"><span itemprop="name">N. Sneeuw</span></a></span></span>. </span><span class="additional-entrytype-information"><span itemtype="http://schema.org/Book" itemscope="itemscope" itemprop="isPartOf"><em><span itemprop="name">Gravity, Geoid and Height Systems</span>, </em></span><em>volume 141 of International Association of Geodesy Symposia, </em><em>page <span itemprop="pagination">21--26</span>. </em><em><span itemprop="publisher">Springer International Publishing Switzerland</span>, </em>(<em><span>2014<meta content="2014" itemprop="datePublished"/></span></em>)</span>Mon Jun 25 10:22:24 CEST 2018Gravity, Geoid and Height Systems21--26International Association of Geodesy SymposiaGOCE Long-Wavelength Gravity Field Recovery from 1s-Sampled Kinematic Orbits Using the Acceleration Approach1412014orbits; field; data GOCE; tracking; orbit satellite-to-satellite kinematic variances; weighting from:mantoni gravity