Surveys in Geophysics最新文献

{"title":"North Atlantic Heat Transport Convergence Derived from a Regional Energy Budget Using Different Ocean Heat Content Estimates","authors":"B. Meyssignac,&nbsp;S. Fourest,&nbsp;Michael Mayer,&nbsp;G. C. Johnson,&nbsp;F. M. Calafat,&nbsp;M. Ablain,&nbsp;T. Boyer,&nbsp;L. Cheng,&nbsp;D. Desbruyères,&nbsp;G. Forget,&nbsp;D. Giglio,&nbsp;M. Kuusela,&nbsp;R. Locarnini,&nbsp;J. M. Lyman,&nbsp;W. Llovel,&nbsp;A. Mishonov,&nbsp;J. Reagan,&nbsp;V. Rousseau,&nbsp;J. Benveniste","doi":"10.1007/s10712-024-09865-5","DOIUrl":"10.1007/s10712-024-09865-5","url":null,"abstract":"<div><p>This study uses an oceanic energy budget to estimate the ocean heat transport convergence in the North Atlantic during 2005–2018. The horizontal convergence of the ocean heat transport is estimated using ocean heat content tendency primarily derived from satellite altimetry combined with space gravimetry. The net surface energy fluxes are inferred from mass-corrected divergence of atmospheric energy transport and tendency of the ECMWF ERA5 reanalysis combined with top-of-the-atmosphere radiative fluxes from the clouds and the Earth’s radiant energy system project. The indirectly estimated horizontal convergence of the ocean heat transport is integrated between the rapid climate change-meridional overturning circulation and heatflux array (RAPID) section at 26.5°N (operating since 2004) and the overturning in the subpolar north atlantic program (OSNAP) section, situated at 53°–60°N (operating since 2014). This is to validate the ocean heat transport convergence estimate against an independent estimate derived from RAPID and OSNAP in-situ measurements. The mean ocean energy budget of the North Atlantic is closed to within ± 0.25 PW between RAPID and OSNAP sections. The mean oceanic heat transport convergence between these sections is 0.58 ± 0.25 PW, which agrees well with observed section transports. Interannual variability of the inferred oceanic heat transport convergence is also in reasonable agreement with the interannual variability observed at RAPID and OSNAP, with a correlation of 0.54 between annual time series. The correlation increases to 0.67 for biannual time series. Other estimates of the ocean energy budget based on ocean heat content tendency derived from various methods give similar results. Despite a large spread, the correlation is always significant meaning the results are robust against the method to estimate the ocean heat content tendency.</p></div>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"45 6","pages":"1855 - 1874"},"PeriodicalIF":4.9,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10712-024-09865-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142488941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Geostationary Satellite-Based Approach to Estimate Convective Mass Flux and Revisit the Hot Tower Hypothesis","authors":"Amel Derras-Chouk,&nbsp;Zhengzhao Johnny Luo","doi":"10.1007/s10712-024-09856-6","DOIUrl":"10.1007/s10712-024-09856-6","url":null,"abstract":"<div><p>This study aims to revisit the classic “hot tower” hypothesis proposed by Riehl and Simpson (Malkus) in 1958 and revisited in 1979. Our investigation centers on the convective mass flux of hot towers within the tropical trough zone, using geostationary (GEO) satellite data and an innovative analysis technique, known as ML16, which integrates various data sources, including hot tower heights, ambient profiles, and a plume model, to determine convective mass flux. The GEO-based ML16 approach is evaluated against collocated ground-based radar wind profiler observations, showing broad agreement. Our GEO-based estimate of hot tower convective mass flux, 2.8 × 10¹¹–3.4 × 10¹¹ kg s⁻¹, is similar to the revisited estimate in Riehl and Simpson (1979), 2.6–3.0 × 10¹¹ kg s⁻¹. Additionally, our analysis gives a median count of around 550 hot towers with a median size of about 11 km, in contrast to the previous estimates of 1600–2400 hot towers, each characterized by a fixed size of 5 km. We discuss the causes of these discrepancies, emphasizing the fundamental differences between the two approaches in characterizing tropical hot towers. While both approaches have various uncertainties, the evidence suggests that greater credibility should be placed on results derived from direct satellite observations. Finally, we identify future opportunities in Earth Observations that will provide more accurate measurements, enabling further evaluation of the role played by tropical hot towers in mass transport.</p></div>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"45 6","pages":"1959 - 1977"},"PeriodicalIF":4.9,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10712-024-09856-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142398016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationships Among Variations in the Earth’s Length-of-Day, Polar Oblateness, and Total Moment of Inertia: A Tutorial Review","authors":"Benjamin F. Chao","doi":"10.1007/s10712-024-09858-4","DOIUrl":"https://doi.org/10.1007/s10712-024-09858-4","url":null,"abstract":"<p>We revisit the derivation of the linear relationships connecting the variations of the Earth’s length-of-day (more specifically its mass term ΔLOD_mass), polar oblateness (Δ<i>J</i>₂), and total moment of inertia (Δ<i>T</i>) caused by geophysical mass transports. The three integral quantities are expressed as inner products of the perturbation, either in the form of density change in the Eulerian description or deformation in the Lagrangian description, with pertinent base functions arising from distinct physical principles. We discuss various cases of mass transport processes regarding whether or not <i>T</i> is conserved, or Δ<i>T</i> = 0. When and only when Δ<i>T</i> = 0, the ΔLOD_mass and Δ<i>J</i>₂ become proportional to each other and hence mutually convertible. This latter practice has long been common, albeit often taken for granted, in the literature notably with respect to the mass transports in surface geophysical fluids and by the glacial isostatic adjustment (GIA) that awaits numerical assessments per physics-based GIA models. We point to subtleties and caveats that tend to be misrepresented, namely, the distinction of ΔLOD_mass from the observed ΔLOD, and the extent of the core’s participation in the angular momentum exchanges across the core-mantle boundary.</p>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"224 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Far-Zone Effects for Spherical Integral Transformations II: Formulas for Horizontal Boundary Value Problems and Their Derivatives","authors":"Michal Šprlák,&nbsp;Martin Pitoňák","doi":"10.1007/s10712-024-09842-y","DOIUrl":"10.1007/s10712-024-09842-y","url":null,"abstract":"<div><p>Integral formulas represent a methodological basis for the determination of gravitational fields generated by planetary bodies. In particular, spherical integral transformations are preferred for their symmetrical properties with the integration domain being the entire surface of the sphere. However, global coverage of boundary values is rarely guaranteed. In practical calculations, we therefore split the spherical surface into a near zone and a far zone, for convenience, by a spherical cap. While the gravitational effect in the near zone can be evaluated by numerical integration over available boundary values, the contribution of the far zone has to be precisely quantified by other means. Far-zone effects for the isotropic integral transformations and those depending on the direct azimuth have adequately been discussed. On the other hand, this subject has only marginally been addressed for the spherical integral formulas that are, except for other variables, also functions of the backward azimuth. In this article, we significantly advance the existing geodetic methodology by deriving the far-zone effects for the two classes of spherical integral transformations: (1) the analytical solutions of the horizontal, horizontal–horizontal, and horizontal–horizontal–horizontal BVPs including their generalisations with arbitrary-order vertical derivative of respective boundary conditions and (2) spatial (vertical, horizontal, or mixed) derivatives of these generalised analytical solutions up to the third order. The integral and spectral forms of the far-zone effects are implemented in MATLAB software package, and their consistency is tested in closed-loop simulations. The presented methodology can be employed in upward/downward continuation of potential field observables or for a quantification of error propagation through spherical integral transformations.</p></div>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"45 5","pages":"1663 - 1713"},"PeriodicalIF":4.9,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10712-024-09842-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"METEOSAT Long-Term Observations Reveal Changes in Convective Organization Over Tropical Africa and Atlantic Ocean","authors":"Rémy Roca,&nbsp;Thomas Fiolleau,&nbsp;Viju O. John,&nbsp;Jörg Schulz","doi":"10.1007/s10712-024-09862-8","DOIUrl":"10.1007/s10712-024-09862-8","url":null,"abstract":"<div><p>In the tropics, deep convection, which is often organized into convective systems, plays a crucial role in the water and energy cycles by significantly contributing to surface precipitation and forming upper-level ice clouds. The arrangement of these deep convective systems, as well as their individual properties, has recently been recognized as a key feature of the tropical climate. Using data from Africa and the tropical Atlantic Ocean as a case study, recent shifts in convective organization have been analyzed through a well-curated, unique record of METEOSAT observations spanning four decades. The findings indicate a significant shift in the occurrence of deep convective systems, characterized by a decrease in large, short-lived systems and an increase in smaller, longer-lived ones. This shift, combined with a nearly constant deep cloud fraction over the same period, highlights a notable change in convective organization. These new observational insights are valuable for refining emerging kilometer-scale climate models that accurately represent individual convective systems but struggle to realistically simulate their overall arrangement.</p></div>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"45 6","pages":"1979 - 1998"},"PeriodicalIF":4.9,"publicationDate":"2024-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10712-024-09862-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142374171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Intradecadal Periodic Signals in GPS Displacements and Their Possible Climate Change Influences","authors":"Hao Ding, WeiPing Jiang, Wei Luan, JianCheng Li, YuanJin Pan, Zhao Li","doi":"10.1007/s10712-024-09864-6","DOIUrl":"https://doi.org/10.1007/s10712-024-09864-6","url":null,"abstract":"<p>Intradecadal changes in GPS displacements have garnered significant attention within the research community; however, the existence of relatively stable intradecadal signals, as well as their characteristics and excitation sources, remains to be further confirmed. This study aims to comprehensively investigate this topic by reviewing relevant existing studies and analyzing over 50 diverse datasets. We first reanalyze two different GPS datasets, and based on those reanalyzed results, we unequivocally validate the existence of at least two intradecadal signals in GPS displacements, a significant ~ 5.9 yr periodic signal (with 4.2 ± 0.95 mm excitation amplitude and a <i>Y</i>_2,2 spatial pattern) as some previous studies suggested and a relatively weak ~ 4.8–5.4 yr signal, and we explain why some previous studies cannot detect the ~ 5.9 yr signal or find its actual spatial pattern. Reevaluating the data from the surface air pressure records (and related records), loading displacements, hydrological records, global mean sea level (GMSL), global mean surface temperature (GMST), and various climate indices demonstrate that there are indeed similar 5–7 yr oscillations as previously suggested, but they have clear differences with the ~ 5.9 yr GPS signal. Additionally, the presence of a ~ 4.7–5.3 yr signal in the in situ hydrological records, as well as a ~ 4.5–5.7 yr signal in surface air pressure, contributes to the ~ 4.8–5.4 yr signal observed in the GPS data, thereby influencing the identification of the 5.9 yr signal. The contrasting outcomes derived from hydrological models and in situ hydrological records indicate that the low-frequency components of the hydrological models lack reliability. As for the precise physical mechanism underlying the ~ 5.9 yr GPS signal, although we have eliminated climate changes as potential sources, it is still difficult to deduce a physical mechanism that could reasonably explain it.</p>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"76 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lost in Translation: The Need for Common Vocabularies and an Interoperable Thesaurus in Earth Observation Sciences","authors":"P. A. Strobl, E. R. Woolliams, K. Molch","doi":"10.1007/s10712-024-09854-8","DOIUrl":"https://doi.org/10.1007/s10712-024-09854-8","url":null,"abstract":"<p>The Earth Observation sciences are highly multidisciplinary with long value chains from the development, characterisation and deployment of sensors, through data processing and modelling, to the information services provided to decision makers in, for example, governments, companies and non-governmental organisations. A prerequisite to any multidisciplinary collaboration is effective communication and many communities involved in the value chains have developed vocabularies or terminologies to define terms from a particular viewpoint or legacy. However, these vocabularies are often inconsistent, with circular definitions, contradictions and using technical terms that are not defined. Here, three case studies from Earth Observation disciplines are considered involving challenges in the definition and use of the terms ‘observation’, ‘in-situ’ and ‘interoperable’. An approach is suggested for an initiative, starting in Earth Observation, to build a consistent thesaurus taking inspiration from the ISO 25964:2011 standard.</p>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"58 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discovery of Physically Interpretable Wave Equations","authors":"Shijun Cheng, Tariq Alkhalifah","doi":"10.1007/s10712-024-09857-5","DOIUrl":"https://doi.org/10.1007/s10712-024-09857-5","url":null,"abstract":"<p>Using symbolic regression to discover physical laws from observed data is an emerging field. In previous work, we combined genetic algorithm (GA) and machine learning to present a data-driven method for discovering a wave equation. Although it managed to utilize the data to discover the two-dimensional (<i>x</i>, <i>z</i>) acoustic constant-density wave equation <span>(u_{tt}=v^2(u_{xx}+u_{zz}))</span> (subscripts of the wavefield, <i>u</i>, are second derivatives in time and space) in a homogeneous medium, it did not provide the complete equation form, where the velocity term is represented by a coefficient rather than directly given by <span>(v^2)</span>. In this work, we redesign the framework, encoding both velocity information and candidate functional terms simultaneously. Thus, we use GA to simultaneously evolve the candidate functional and coefficient terms in the library. Also, we consider here the physics rationality and interpretability in the randomly generated potential wave equations, by ensuring that both-hand sides of the equation maintain balance in their physical units. We demonstrate this redesigned framework using the acoustic wave equation as an example, showing its ability to produce physically reasonable expressions of wave equations from noisy and sparsely observed data in both homogeneous and inhomogeneous media. Also, we demonstrate that our method can effectively discover wave equations from a more realistic observation scenario.</p>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"28 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142321266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Global Energy Balance as Represented in Atmospheric Reanalyses","authors":"Martin Wild,&nbsp;Michael G. Bosilovich","doi":"10.1007/s10712-024-09861-9","DOIUrl":"10.1007/s10712-024-09861-9","url":null,"abstract":"<div><p>In this study, we investigate the representation of the global mean energy balance components in 10 atmospheric reanalyses, and compare their magnitudes with recent reference estimates as well as the ones simulated by the latest generation of climate models from the 6th phase of the coupled model intercomparison project (CMIP6). Despite the assimilation of comprehensive observational data in reanalyses, the spread amongst the magnitudes of their global energy balance components generally remains substantial, up to more than 20 Wm⁻² in some quantities, and their consistency is typically not higher than amongst the much less observationally constrained CMIP6 models. Relative spreads are particularly large in the reanalysis global mean latent heat fluxes (exceeding 20%) and associated intensity of the global water cycle, as well as in the energy imbalances at the top-of-atmosphere and surface. A comparison of reanalysis runs in full assimilation mode with corresponding runs constrained only by sea surface temperatures reveals marginal differences in their global mean energy balance components. This indicates that discrepancies in the global energy balance components caused by the different model formulations amongst the reanalyses are hardly alleviated by the imposed observational constraints from the assimilation process. Similar to climate models, reanalyses overestimate the global mean surface downward shortwave radiation and underestimate the surface downward longwave radiation by 3–7 Wm⁻²<i>.</i> While reanalyses are of tremendous value as references for many atmospheric parameters, they currently may not be suited to serve as references for the magnitudes of the global mean energy balance components.</p></div>","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"45 6","pages":"1799 - 1825"},"PeriodicalIF":4.9,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10712-024-09861-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142276091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction: Investigation of Fluid Types in Shale Oil Reservoirs","authors":"Xiaojiao Pang,&nbsp;Guiwen Wang,&nbsp;Lichun Kuang,&nbsp;Jin Lai,&nbsp;Nigel P. Mountney","doi":"10.1007/s10712-024-09851-x","DOIUrl":"10.1007/s10712-024-09851-x","url":null,"abstract":"","PeriodicalId":49458,"journal":{"name":"Surveys in Geophysics","volume":"45 5","pages":"1595 - 1600"},"PeriodicalIF":4.9,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142234213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}