The SARSense Campaign: Air- and Space-Borne C- and L-Band SAR for the Analysis of Soil and Plant Parameters in Agriculture

With the upcoming L-band Synthetic Aperture Radar (SAR) satellite mission Radar Observing System for Europe at L-band (ROSE-L) and its combination with existing C-band satellite missions such as Sentinel-1, multi-frequency SAR observations with high temporal and spatial resolution will become available. To investigate the potential for estimating soil and plant parameters, the SARSense campaign was conducted between June and August 2019 at the agricultural test site Selhausen in Germany. In this regard, we introduce a new publicly available, extensive SAR dataset and present a first analysis of C- and L-band co- and cross-polarized backscattering signals regarding their sensitivity to soil and plant parameters. The analysis includes C- and L-band airborne recordings as well as Senitnel-1 and ALOS-2 acquisitions, accompanied by in-situ soil moisture measurements and plant samplings. In addition, soil moisture was measured using cosmic-ray neutron sensing as well as unmanned aerial system (UAS) based multispectral and temperature measurements were taken during the campaign period. First analysis of the dataset revealed, that due to misalignments of corner reflectors during the SAR acquisition, temporal consistency of airborne SAR data is not given. In this regard, a scene-based, spatial analysis of backscatter behaviour from airborne SAR data was conducted, while the spaceborne SAR data enabled the analysis of temporal changes in backscatter behaviour. Focusing on root crops with radial canopy structure (sugar beet and potato) and cereal crops with elongated canopy structure (wheat, barley), the lowest correlations can be observed between backscattering signal and soil moisture, with R&#178; values ranging below 0.35 at C-band and below 0.36 at L-band. Higher correlations can be observed focusing on vegetation water content, with R&#178; values ranging between 0.12 and 0.64 at C-band and 0.06 and 0.64 at L-band. Regarding plant height, at C-band higher correlations with R&#178; up to 0.55 can be seen compared to R&#178; up to 0.36 at L-band. Looking at the individual agricultural corps in more detail, in almost all cases, the backscatter signals of C- and L-band contain a different amount of information about the soil and plant parameters, indicating that a multi-frequency approach is envisaged to disentangle soil and plant contributions to the signal and to identify specific scattering mechanisms related to the crop type, especially related to the different characteristics of root crops and cereals.

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An Intercomparison of GPS RO Retrievals with Colocated Analysis and In Situ Observations within Tropical Cyclones

Advances in Meteorology ◽

10.1155/2010/715749 ◽

2010 ◽

Vol 2010 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Henry R. Winterbottom ◽

Qingnong Xiao

Keyword(s):

Tropical Cyclones ◽

Global Positioning System ◽

Global Analysis ◽

Reanalysis Data ◽

Satellite Mission ◽

Data Set ◽

Global Positioning ◽

In Situ Observations ◽

Atmospheric State

Observations from four Global Position System (GPS) Radio Occultation (RO) missions: Global Positioning System/Meteorology, CHAallenging Minisatellite Payload, Satellite de Aplicaciones Cientificas-C, and Constellation Observing System for Meteorology, Ionosphere and Climate and Taiwan's FORMOsa SATellite Mission #3 (COSMIC/FORMOSAT-3) are collected within a 600 km radius and ±180 minute temporal window of all observed tropical cyclones (TCs) from 1995 to 2006 that were recorded in the global hurricane best-track reanalysis data set (Jarvinen et al. (1984); Davis et al. (1984)). A composite analysis of tropical cyclone radial mean temperature and water vapor profiles is carried out using the GPS RO retrievals which are colocated with global analysis profiles and available in situ radiosonde observations. The differences between the respective observations and analysis profiles are quantified and the preliminary results show that the observations collected within TCs correspond favorably with both the analysis and radiosonde profiles which are colocated. It is concluded that GPS RO observations will contribute significantly to the understanding and modeling of TC structures, especially those related to vertical variability of the atmospheric state within TCs.

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Towards the removal of model bias from ESA CCI SM by using an L-band scaling reference

10.5194/egusphere-egu21-4800 ◽

2021 ◽

Author(s):

Rémi Madelon ◽

Nemesio Rodriguez-Fernandez ◽

Robin Van Der Shalie ◽

Yann Kerr ◽

Tracy Scalon ◽

...

Keyword(s):

Time Series ◽

Soil Moisture ◽

Climate Models ◽

In Situ Measurements ◽

Time Data ◽

Data Set ◽

Spatial Coverage ◽

L Band ◽

Better Than

Merging data from different instruments is required to construct long time data records of soil moisture (SM). This is the goal of projects such as the ESA Climate Change Initiative (CCI) for SM (Gruber et al., 2019), which uses both active and passive microwave sensors. Currently, the GLDAS v2.1 model is used as reference to re-scale active and passive time series by matching their Cumulative Density Function (CDF) to that of the model. Removing the dependency on models is important, in particular for data assimilation applications into hydrological or climate models, and it has been proposed (Van der Schalie et al., 2018) to use L-band data from one of the two instruments specifically designed to measure SM, ESA Soil Moisture and Ocean Salinity (SMOS) and NASA Soil Moisture Active Passive (SMAP) satellites, as reference to re-scale other time series. To investigate this approach, AMSR-2 SM time series obtained from C1-, C2- and X-band observations using LPRM (Land Parameter Retrieval Model) were re-scaled by CDF-matching (Brocca et al., 2011) using different SMAP and SMOS official (SMAP L2 V005, SMOS L3 V300, SMOS NRT V100&V200) and research (SMOS IC V103) SM products as well as the SMAP and SMOS LPRM v6 SM data used by the ESA CCI. The time series re-scaled using L-band remote sensing data were compared to those re-scaled using GLDAS and were evaluated against in situ measurements at several hundred sites retrieved from the International Soil Moisture Network (Dorigo et al., 2011). The results were analyzed as a function of the land cover class and the Koppen-Geiger climate classification. Overall, AMSR-2 time series re-scaled using SMAP L2, SMAP LPRM and SMOS IC data sets as reference gave the best correlations with respect to in situ measurements, similar to those obtained by the time series re-scaled using GLDAS and slightly better than those of the original AMSR-2 time series. These results imply that different SMAP and SMOS products could actually be used to replace GLDAS as reference for the re-scaling of other sensors time series within the ESA CCI. However, one must bear in mind that this study is limited to the re-scaling of AMSR-2 data at a few hundred sites. For a more detailed assessment of the L-band data set to be used for a global re-scaling, it is necessary to investigate other effects such as the spatial coverage or the time series length. SMAP spatial coverage is better than that of SMOS in regions affected by radio frequency interference. In contrast, the length of SMAP time series can be too short to capture the long term SM variability for climate applications in some regions. The CDF of SMOS time series computed from the date of SMAP launch is significantly different to those of the full length SMOS time series in some regions of the Globe. Possible ways of using a coherent SMAP/SMOS L-band data set will be discussed.

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Spatio-Temporal Mapping of L-Band Microwave Emission on a Heterogeneous Area with ELBARA III Passive Radiometer

Sensors ◽

10.3390/s19163447 ◽

2019 ◽

Vol 19 (16) ◽

pp. 3447

Author(s):

Łukasz Gluba ◽

Mateusz Łukowski ◽

Radosław Szlązak ◽

Joanna Sagan ◽

Kamil Szewczak ◽

...

Keyword(s):

Soil Moisture ◽

Water Resources ◽

Microwave Radiometer ◽

European Space Agency ◽

Test Site ◽

Microwave Emission ◽

Satellite Mission ◽

Space Agency ◽

L Band ◽

Spatio Temporal

Water resources on Earth become one of the main concerns for society. Therefore, remote sensing methods are still under development in order to improve the picture of the global water cycle. In this context, the microwave bands are the most suitable to study land–water resources. The Soil Moisture and Ocean Salinity (SMOS), satellite mission of the European Space Agency (ESA), is dedicated for studies of the water in soil over land and salinity of oceans. The part of calibration/validation activities in order to improve soil moisture retrieval algorithms over land is done with ground-based passive radiometers. The European Space Agency L-band Microwave Radiometer (ELBARA III) located near the Bubnów wetland in Poland is capable of mapping microwave emissivity at the local scale, due to the azimuthal and vertical movement of the horn antenna. In this paper, we present results of the spatio-temporal mapping of the brightness temperatures on the heterogeneous area of the Bubnów test-site consisting of an area with variable organic matter (OM) content and different type of vegetation. The soil moisture (SM) was retrieved with the L-band microwave emission of the biosphere (L-MEB) model with simplified roughness parametrization (SRP) coupling roughness and optical depth parameters. Estimated soil moisture values were compared with in-situ data from the automatic agrometeorological station. The results show that on the areas with a relatively low OM content (4–6%—cultivated field) there was good agreement between measured and estimated SM values. Further increase in OM content, starting from approximately 6% (meadow wetland), caused an increase in bias, root mean square error (RMSE), and unbiased RMSE (ubRMSE) values and a general drop in correlation coefficient (R). Despite a span of obtained R values, we found that time-averaged estimated SM using the L-MEB SRP approach strongly correlated with OM contents.

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Paleoenvironmental analysis of the Hautawa Shellbed, Whanganui Basin

10.26686/wgtn.17134148.v1 ◽

2021 ◽

Author(s):

◽

Joanna Eveline Grace Elliott

Keyword(s):

Principal Component ◽

Data Set ◽

Sequence Stratigraphic ◽

Fine Grained ◽

Temporal And Spatial ◽

On Farm ◽

Subunit B ◽

Lateral Variations ◽

Paleoenvironmental Analysis

The Hautawa Shellbed, Whanganui Basin is described in detail to uncover lateral variations in depositional paleoenvironment. This was achieved through the in situ documentation of the macrofaunal assemblage and its taphonomic attributes at three localities. The sites from west to east are: Ridge Road, Old Hautawa Road, and the type section on West Road. They are all exposures on farm tracks and cover a 20-km range across the central Whanganui Basin. The descriptions were collected at 15-cm intervals and analysed using k-means clustering and Principal Component Analysis (PCA) to uncover trends within the data set. Combining the assemblage data with the taphonomic has allowed six major biofacies to be recognised. In turn, the arrangement of the biofacies in the sections suggest three subunits: A, B, and C. Subunits A and C are laterally continuous between all of the sections and always relate to the lowermost and upper-most portions of the Hautawa Shellbed. In contrast, subunit B is only observed to occur at West Road overlying subunit A. These subunits have can also be equated to sequence stratigraphic terminology. Subunits A and B form an onlap shellbed and subunit C a backlap shellbed. Hence, the Hautawa Shellbed represents deposition during the transgressive systems tract of a single cyclothem. This study is unique compared to other Whanganui Basin stratigraphic research in its statistically robust approach for comparing data gathered at various sites along outcrop strike to better understand the preserved paleoenvironment. To support the macro-faunal investigation, census counts of foraminifera were conducted for samples collected from the fine-grained sediments encompassing the Hautawa Shellbed at each of the three sites. Together, the macrofaunal and foraminiferal studies reveal temporal and spatial paleoenvironmental changes within the Hautawa Shellbed. The presence of biostratigraphically important fauna within the Hautawa Shellbed has been used to link the unit to other similar formations in both the Whanganui and East Coast Basins. This key assemblage which highlights the Nukumaruan-Mangapanian Stage boundary at 2.40 Ma includes: Zygochlamys delicatula, Crassostrea ingens, Phialopecten thomsoni, Phialopecten triphooki, and Mesopeplum convexum. The paleoenvironmental variations observed and presented here for the Hautawa Shellbed have been combined with published work on other parallel formations to produce a paleogeographic map of the Whanganui Basin for 2.40 Ma.

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Paleoenvironmental analysis of the Hautawa Shellbed, Whanganui Basin

10.26686/wgtn.17134148 ◽

2021 ◽

Author(s):

◽

Joanna Eveline Grace Elliott

Keyword(s):

Principal Component ◽

Data Set ◽

Sequence Stratigraphic ◽

Fine Grained ◽

Temporal And Spatial ◽

On Farm ◽

Subunit B ◽

Lateral Variations ◽

Paleoenvironmental Analysis

The Hautawa Shellbed, Whanganui Basin is described in detail to uncover lateral variations in depositional paleoenvironment. This was achieved through the in situ documentation of the macrofaunal assemblage and its taphonomic attributes at three localities. The sites from west to east are: Ridge Road, Old Hautawa Road, and the type section on West Road. They are all exposures on farm tracks and cover a 20-km range across the central Whanganui Basin. The descriptions were collected at 15-cm intervals and analysed using k-means clustering and Principal Component Analysis (PCA) to uncover trends within the data set. Combining the assemblage data with the taphonomic has allowed six major biofacies to be recognised. In turn, the arrangement of the biofacies in the sections suggest three subunits: A, B, and C. Subunits A and C are laterally continuous between all of the sections and always relate to the lowermost and upper-most portions of the Hautawa Shellbed. In contrast, subunit B is only observed to occur at West Road overlying subunit A. These subunits have can also be equated to sequence stratigraphic terminology. Subunits A and B form an onlap shellbed and subunit C a backlap shellbed. Hence, the Hautawa Shellbed represents deposition during the transgressive systems tract of a single cyclothem. This study is unique compared to other Whanganui Basin stratigraphic research in its statistically robust approach for comparing data gathered at various sites along outcrop strike to better understand the preserved paleoenvironment. To support the macro-faunal investigation, census counts of foraminifera were conducted for samples collected from the fine-grained sediments encompassing the Hautawa Shellbed at each of the three sites. Together, the macrofaunal and foraminiferal studies reveal temporal and spatial paleoenvironmental changes within the Hautawa Shellbed. The presence of biostratigraphically important fauna within the Hautawa Shellbed has been used to link the unit to other similar formations in both the Whanganui and East Coast Basins. This key assemblage which highlights the Nukumaruan-Mangapanian Stage boundary at 2.40 Ma includes: Zygochlamys delicatula, Crassostrea ingens, Phialopecten thomsoni, Phialopecten triphooki, and Mesopeplum convexum. The paleoenvironmental variations observed and presented here for the Hautawa Shellbed have been combined with published work on other parallel formations to produce a paleogeographic map of the Whanganui Basin for 2.40 Ma.

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Modeling of an in-situ diffusion experiment in granite at the Grimsel Test Site

MRS Proceedings ◽

10.1557/opl.2014.632 ◽

2014 ◽

Vol 1665 ◽

pp. 85-91 ◽

Cited By ~ 2

Author(s):

Josep M. Soler ◽

Jiri Landa ◽

Vaclava Havlova ◽

Yukio Tachi ◽

Takanori Ebina ◽

...

Keyword(s):

Effective Diffusion ◽

Test Site ◽

Diffusion Experiment ◽

Bulk Rock ◽

Disturbed Zone ◽

Mean Grain Size ◽

Grimsel Test Site ◽

In Situ Diffusion

ABSTRACTMatrix diffusion is a key process for radionuclide retention in crystalline rocks. Within the LTD project (Long-Term Diffusion), an in-situ diffusion experiment in unaltered non-fractured granite was performed at the Grimsel Test Site (www.grimsel.com, Switzerland). The tracers included 3H as HTO, 22Na+, 134Cs+ and 131I- with stable I- as carrier.The dataset (except for 131I- because of complete decay) was analyzed with different diffusion-sorption models by different teams (NAGRA / IDAEA-CSIC, UJV-Rez, JAEA, Univ. Poitiers) using different codes, with the goal of obtaining effective diffusion coefficients (De) and porosity (ϕ) or rock capacity (α) values. A Borehole Disturbed Zone (BDZ), which was observed in the rock profile data for 22Na+ and 134Cs+, had to be taken into account to fit the experimental observations. The extension of the BDZ (1-2 mm) was about the same magnitude as the mean grain size of the quartz and feldspar grains.De and α values for the different tracers in the BDZ are larger than the respective values in the bulk rock. Capacity factors in the bulk rock are largest for Cs+ (strong sorption) and smallest for 3H (no sorption). However, 3H seems to display large α values in the BDZ. This phenomenon will be investigated in more detail in a second test starting in 2013.

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Non-intrusive in-situ permittivity measurements dedicated to the development of a P and L band dielectric model of wood

10.1109/igarss47720.2021.9553733 ◽

2021 ◽

Author(s):

F. Demontoux ◽

M. Gati ◽

M. el Boudali ◽

L. Villard ◽

JP Wigneron ◽

...

Keyword(s):

Dielectric Model ◽

L Band ◽

Permittivity Measurements

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Für Wetter und Klima – Maritim-Meteorologische Observationen beim DWD

10.5194/dach2022-300 ◽

2021 ◽

Author(s):

Axel Andersson ◽

Henry Kleta ◽

Hildrun Otten-Balaccanu ◽

Thomas Möller

Keyword(s):

Wird Eine ◽

Data Set ◽

Ocean Atmosphere ◽

Global Data

Die Erfassung und &#220;berwachung des Wetters und des Klimas auf den Weltmeeren hat eine lange Tradition beim Deutschen Wetterdienst (DWD) und seinen Vorg&#228;ngerorganisationen in Hamburg. Seit dem 19. Jahrhundert werden auf Schiffen systematisch meteorologische und ozeanographische Informationen gesammelt, die ein detailliertes Verst&#228;ndnis des maritimen Wetters und des Klimas erm&#246;glichen. Bis heute sind die meteorologischen Schiffsbeobachtungen eine wichtige Datenquelle f&#252;r die Wettervorhersage und die Klima&#252;berwachung. Der Deutsche Wetterdienst betreibt ein gro&#223;es meteorologisches maritimes Messnetz, welches mehr als 500 Schiffe umfasst, die regelm&#228;&#223;ig Wetterbeobachtungen auf allen Weltmeeren durchf&#252;hren. Diese Schiffe beteiligen sich am internationalen Voluntary Observing Ship (VOS) Scheme und ihre Beobachtungen werden in Echtzeit &#252;ber das globale Telekommunikationssystem (GTS) der WMO verbreitet. Dabei wird eine zunehmende Anzahl von Beobachtungen von automatischen Wetterstationen an Bord von Schiffen geliefert. Neben der Nutzung f&#252;r die operationelle Wettervorhersage sind die maritim-meteorologischen Observationen ein wichtiger Beitrag zu klimatologischen Archiven wie der In-situ Datenbank des maritimen Klimadatenzentrums des DWD. Diese Datenbank besteht aus qualit&#228;tskontrollierten Daten aus Echtzeit- und delayed mode Datenstr&#246;men, sowie aus einer gro&#223;en Menge historischer Daten. Der Datenbestand w&#228;chst kontinuierlich durch aktuelle operationelle Dateneing&#228;nge, aber auch durch die Digitalisierung alter meteorologischer Schiffsjournale und reicht von heute bis weit zur&#252;ck in das 19 Jahrhundert. Im Rahmen des internationalen Datenaustauschs &#252;ber die WMO / IOC VOS Global Data Assembly Centres (GDACs) werden die maritimen Klimadaten regelm&#228;&#223;ig in den International Comprehensive Ocean-Atmosphere Data Set (ICOADS) integriert. Des Weiteren werden die Daten f&#252;r eine Vielzahl von Klimaanwendungen verwendet, z.B. als Input f&#252;r Reanalysen, f&#252;r die operationelle Klima&#252;berwachung, klimatologische Analysen und Datenprodukte, sowie f&#252;r die Kalibrierung von Satellitenbeobachtungen.

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Two decades of in-situ temperature measurements in the upper troposphere and lowermost stratosphere from IAGOS long-term routine observation

10.5194/acp-2017-494 ◽

2017 ◽

Author(s):

Florian Berkes ◽

Patrick Neis ◽

Martin G. Schultz ◽

Ulrich Bundke ◽

Susanne Rohs ◽

...

Keyword(s):

Weather Forecast ◽

Global Scale ◽

Temperature Trend ◽

Data Set ◽

Medium Range Weather Forecast ◽

Upper Troposphere ◽

Temperature Trends ◽

Geographical Regions

Abstract. Despite several studies on temperature trends in the tropopause region, a comprehensive understanding of the evolution of temperatures in this climate-sensitive region of the atmosphere remains elusive. Here we present a unique global-scale, long-term data set of high-resolution in-situ temperature data measured aboard passenger aircraft within the European Research Infrastructure IAGOS (In-service Aircraft for a Global Observing System, www.iagos.org). This data set is used to investigate temperature trends within the global upper troposphere and lowermost stratosphere (UTLS) for the period 1995 to 2012 in different geographical regions and vertical layers of the UTLS. The largest amount of observations is available over the North Atlantic. Here, a neutral temperature trend is found within the lowermost stratosphere. This contradicts the temperature trend in the European Centre for Medium Range Weather Forecast (ECMWF) ERA-Interim reanalysis, where a significant (95 % confidence) temperature increase of +0.56 K/decade is obtained. Differences between trends derived from observations and reanalysis data can be traced back to changes in the temperature bias between observation and model data over the studied period. This study demonstrates the value of the IAGOS temperature observations as anchor point for the evaluation of reanalyses and its suitability for independent trend analyses.

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