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1

A script-driven approach to mapping satellite-derived topography and gravity data over the Zagros Fold-and-Thrust Belt, Iran

Lemenkova Polina

Artificial Satellites : Journal of Planetary Geodesy

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2022

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Vol. 57, No. 2

110--137

EN

Integrated geophysical mapping benefits from visualizing multi-source datasets including gravity and satellite altimetry data using 2D and 3D techniques. Applying scripting cartographic approach by R language and GMT supported by traditional mapping in QGIS is presented in this paper with a case study of Iranian geomorphology and a special focus on Zagros Fold-and-Thrust Belt, a unique landform of the country affected by complex geodynamic structure. Several modules of GMT and ’tmap’ and ’raster’ packages of R language were shown to illustrate the efficiency of the console-based mapping by scripts. Data sources included high-resolution raster grids of GEBCO/SRTM, EGM-2008, SRTM DEM and vector geologic layers of USGS. The cartographic objective was to visualize thematic maps of Iran: topography, geology, satellite-derived gravity anomalies, geoid undulations and geomorphology. Various cartographic techniques were applied to plot the geophysical and topographic field gradients and categorical variations in geological structures and relief along the Zagros Fold-and-Thrust Belt. The structures of Elburz, Zagros, Kopet Dag and Makran slopes, Dasht-e Kavir, Dasht-e Lut and Great Salt Desert were visualized using 3D-and 2D techniques. The geomorphometric properties (slope, aspect, hillshade, elevations) were modelled by R. The study presented a series of 11 new maps made using a combination of scripting techniques and GIS for comparative geological-geophysical analysis. Listings of R and GMT scripting are provided for repeatability.

2

Studying the Sensitivity of Satellite Altimetry, Tide Gauge and GNSS Observations to Changes in Vertical Displacements

Pająk Katarzyna, Kowalczyk Kamil, Kaminskis Jānis, Idzikowska Magdalena

Geomatics and Environmental Engineering

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2021

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Vol. 15, no. 4

45--58

EN

Tide gauge observations provide sea level relative to the Earth’s crust, while satellite altimetry measures sea level variations relative to the centre of the Earth’s mass. Local vertical land motion can be a significant contribution to the measured sea level change. Satellite altimetry was traditionally used to study the open ocean, but this technology is now being used over inland seas too. The difference of both observations can be used to estimate vertical crustal movement velocities along the sea coast. In this paper, vertical crustal movement velocities were investigated at tide gauge sites along the Adriatic Sea coast by analyzing differences between Tide Gauge (TG) and Satellite Altimetry (SA) observations. Furthermore, the estimated vertical motion rates were compared with those from nearby GNSS measurements. The study determines the practical relationships between these vertical crustal movements and those determined from unrelated data acquired from the neighbouring GNSS stations. The results show general consistence with the present geodynamics in the Adriatic Sea coastal zone.

3

Zmiany poziomu morza : przyczyny, skale czasowe i historia ich poznania

Boski Tomasz, Wilamowski Andrzej

Przegląd Geologiczny

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2020

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Vol. 68, nr 11

820--823

EN

Sea level changes provoked by multiple forcings that act in a wide range of time scales attracted human interest for several millennia. However, the bases of modern understanding of this phenomenon and its quantitative expression were achieved during the last two centuries. At present, owing to a series of altimetric observations made by 4 satellite missions in the last 30years, the mean sea level (MSL) rise calculated for the whole Earth is estimated to be 3-3.5 mm per year, with at least half of this value being attributable to human-induced climate warming. About 125,000 years ago, during the last interglacial (Eemian) that was warmer than the current period, the MSL was about 5 m higher than today. Approximately 116,000 years ago, the sea level began to decline as a result of gradual cooling of the climate that led to glaciation, which in the Northern Hemisphere had a climax at 20-30 ka BP. The transition from the last glacial maximum to the current warm period, covering the last 20,000years, includes the transfer of about 35 106 km3 of water from melting ice caps of the Northern Hemisphere to the oceanic reservoir, causing an increase in sea level of about 130 m. The average rate of MSL rise was about 10 mm per year, although over the last seven millennia, the MSL rising rate dropped to about 1-1.5 mm per year. These changes are considered representative of the natural variability of the Earth's climate system over the past 2 million years.

4

Current state of art of satellite altimetry

Łyszkowicz A. B., Bernatowicz A.

Geodesy and Cartography

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2017

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Vol. 66, no. 2

259--270

EN

One of the fundamental problems of modern geodesy is precise defi nition of the gravitational fi eld and its changes in time. This is essential in positioning and navigation, geophysics, geodynamics, oceanography and other sciences related to the climate and Earth’s environment. One of the major sources of gravity data is satellite altimetry that provides gravity data with almost 75% surface of the Earth. Satellite altimetry also provides data to study local, regional and global geophysical processes, the geoid model in the areas of oceans and seas. This technique can be successfully used to study the ocean mean dynamic topography. The results of the investigations and possible products of altimetry will provide a good material for the GGOS (Global Geodetic Observing System) and institutions of IAS (International Altimetry Service). This paper presents the achievements in satellite altimetry in all the above disciplines obtained in the last years. First very shorly basic concept of satellite altimetry is given. In order to obtain the highest accuracy on range measurements over the ocean improved of altimetry waveforms performed on the ground is described. Next, signifi cant improvements of sea and ocean gravity anomalies models developed presently is shown. Study of sea level and its extremes examined, around European and Australian coasts using tide gauges data and satellite altimetry measurements were described. Then investigations of the phenomenon of the ocean tides, calibration of altimeters, studies of rivers and ice-sheets in the last years are given.

5

Current State of Deep Ocean Bathymetric Exploration

Zwolak K., Felski A.

Annual of Navigation

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2017

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No. 24

257--267

EN

The paper presents current state of bathymetric survey concerning deep ocean rather than shallow areas, which are better surveyed due to safety of navigation concerns. Rules and requirements of the new challenge, called the Shell Ocean Discovery XPRIZE, became a starting point for a discussion about the possibilities of mapping large areas of the ocean using up-to-date and new technology. The amount of bathymetric data available nowadays and the current state of ocean map compilations are also discussed in the paper as a motivation to inspire the new initiatives in the deep ocean.

PL

W artykule przedstawiono obecny stan pomiarów batymetrycznych głębokowodnych obszarów oceanicznych. Zasady najnowszego konkursu Shell Ocean Discovery XPRIZE stały się punktem wyjścia do dyskusji o obecnych możliwościach pozyskiwania danych niezbędnych do tworzenia map oceanów w oparciu o aktualnie dostępne technologie. W artykule poruszono również zagadnienie ilości i cech danych batymetrycznych znajdujących się i udostępnianych w bazach danych gromadzących tego typu informacje.

6

Current State of Art of Satellite Altimetry

Łyszkowicz A., Bernatowicz A.

Annual of Navigation

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2017

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No. 24

31--47

EN

One of the fundamental problems of modern geodesy is precise definition of the gravitational field and its changes in time. This is essential in positioning and navigation, geophysics, geodynamics, oceanography and other sciences related to the climate and Earth’s environment. One of the major sources of gravity data is satellite altimetry that provides gravity data with almost 75% surface of the Earth. Satellite altimetry also provides data to study local, regional and global geophysical processes, the geoid model in the areas of oceans and seas. This technique can be successfully used to study the ocean mean dynamic topography. The results of the investigations and possible products of altimetry will provide a good material for the GGOS (Global Geodetic Observing System) and institutions of IAS (International Altimetry Service). This paper presents the achievements in satellite altimetry in all the above disciplines obtained in the last years.

PL

Jednym z podstawowych problemów współczesnej geodezji jest dokładne określenie pola grawitacyjnego i jego zmian w czasie. Ma to zasadnicze znaczenie dla zastosowań w pozycjonowaniu i nawigacji, w geofizyce, geodynamice, oceanografii i innych naukach związanych z klimatem i środowiskiem Ziemi. Jednym z głównych źródeł danych grawimetrycznych jest altimetria satelitarna, która dostarcza dane grawimetryczne z prawie 75% powierzchni globu ziemskiego. Altimetria satelitarna dostarcza również dane do badania lokalnych, regionalnych i globalnych procesów geofizycznych, modelu geoidy na obszarach mórz i oceanów oraz średniej dynamicznej topografii oceanów. Wyniki badań i potencjalne produkty danych altimetrycznych mają stanowić materiał dla Globalnego Geodezyjnego Systemu Obserwacji GGOS (Global Geodetic Observing System) i instytucji IAS (International Altimetry Service).

7

Non-linear sea level variations in the eastern tropical Pacific

Niedzielski T.

Artificial Satellites : Journal of Planetary Geodesy

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2010

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Vol. 45, No. 1

1--10

EN

The objective of this paper is to provide an insightful interpretation for the non-linearity of the inter-annual signal in sea level change in the eastern tropical Pacific. Such a non-linearity has been already discussed elsewhere for global ocean. Herein, the residual sea level anomaly time series from TOPEX/Poseidon and Jason-1 altimetry is obtained by removing the significant deterministic signals from the original sea level anomaly data. Since the eastern tropical Pacific is a profound region where many processes responsible for driving the El Niño/Southern Oscillation (ENSO) act, it is possible to link a few of them with the non-linearity of sea level change. In particular, not only local, usually weak, oceanatmosphere interactions exist in the eastern equatorial Pacific but this region is also remotely impacted by climatic processes acting in the western equatorial Pacific where the oceanatmosphere coupling is the strongest. The detected non-linearity of sea level change is due to the asymmetry between warm and cold ENSO episodes. Such an asymmetry can be driven by the non-linear dynamical heating associated with strong ENSO events.