The International DORIS Service (IDS) - Recent Developments in Preparation for ITRF2013

The International DORIS Service (IDS) was created in 2003 under the umbrella of the International Association of Geodesy (IAG) to foster scientific research related to the French DORIS tracking system and to deliver scientific products, mostly related to the International Earth rotation and Reference systems Service (IERS). We first present some general background related to the DORIS system (current and planned satellites, current tracking network and expected evolution) and to the general IDS organization (from Data Centers, Analysis Centers and Combination Center). Then, we discuss some of the steps recently taken to prepare the IDS submission to ITRF2013 (combined weekly time series based on individual solutions from several Analysis Centers). In particular, recent results obtained from the Analysis Centers and the Combination Center show that improvements can still be made when updating physical models of some DORIS satellites, such as Envisat, Cryosat-2 or Jason-2. The DORIS contribution to ITRF2013 should also benefit from the larger number of ground observations collected by the last generation of DGXX receivers (first instrument being onboard Jason-2 satellite). In particular for polar motion, sub-millarcsecond accuracy seems now to be achievable. Weekly station positioning internal consistency also seems to be improved with a larger DORIS constellation

Bureau of Networks and Observations

Role of the Bureau: To advocate and encourage implementation of the Core and Co-location Network to satisfy GGOS requirements, to monitor the status of the network and project its future condition, and to support and advocate for infrastructure critical for the development of data products essential to GGOS

Update on the activities of the GGOS Bureau of Networks and Observations

The recently reorganized GGOS Bureau of Networks and Observations has many elements that are associated with building and sustaining the infrastructure that supports the Global Geodetic Observing System (GGOS) through the development and maintenance of the International Terrestrial and Celestial Reference Frames, improved gravity field models and their incorporation into the reference frame, the production of precision orbits for missions of interest to GGOS, and many other applications. The affiliated Service Networks (IVS, ILRS, IGS, IDS, and now the IGFS and the PSMSL) continue to grow geographically and to improve core and co-location site performance with newer technologies. Efforts are underway to expand GGOS participation and outreach. Several groups are undertaking initiatives and seeking partnerships to update existing sites and expand the networks in geographic areas void of coverage. New satellites are being launched by the Space Agencies in disciplines relevant to GGOS. Working groups now constitute an integral part of the Bureau, providing key service to GGOS. Their activities include: projecting future network capability and examining trade-off options for station deployment and technology upgrades, developing metadata collection and online availability strategies; improving coordination and information exchange with the missions for better ground-based network response and space-segment adequacy for the realization of GGOS goals; and standardizing site-tie measurement, archiving, and analysis procedures. This poster will present the progress in the Bureau's activities and its efforts to expand the networks and make them more effective in supporting GGOS

Liver-Targeting of Interferon-Alpha with Tissue-Specific Domain Antibodies

PMCID: PMC3581439This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Sen2Like: Paving the Way towards Harmonization and Fusion of Optical Data

Satellite Earth Observation (EO) sensors are becoming a vital source of information for land surface monitoring. The concept of the Virtual Constellation (VC) is gaining interest within the science community owing to the increasing number of satellites/sensors in operation with similar characteristics. The establishment of a VC out of individual missions offers new possibilities for many application domains, in particular in the fields of land surface monitoring and change detection. In this context, this paper describes the Copernicus Sen2Like algorithms and software, a solution for harmonizing and fusing Landsat 8/Landsat 9 data with Sentinel-2 data. Developed under the European Union Copernicus Program, the Sen2Like software processes a large collection of Level 1/Level 2A products and generates high quality Level 2 Analysis Ready Data (ARD) as part of harmonized (Level 2H) and/or fused (Level 2F) products providing high temporal resolutions. For this purpose, we have re-used and developed a broad spectrum of data processing and analysis methodologies, including geometric and spectral co-registration, atmospheric and Bi-Directional Reflectance Distribution Function (BRDF) corrections and upscaling to 10 m for relevant Landsat bands. The Sen2Like software and the algorithms have been developed within a VC establishment framework, and the tool can conveniently be used to compare processing algorithms in combinations. It also has the potential to integrate new missions from spaceborne and airborne platforms including unmanned aerial vehicles. The validation activities show that the proposed approach improves the temporal consistency of the multi temporal data stack, and output products are interoperable with the subsequent thematic analysis processes

Sen2Like: a processor for harmonising and fusing optical imaging data

Earth Observation (EO) is becoming a vital source of information for land surface monitoring. The concept of Virtual Constellation (VC) is born with the increasing number of satellites / sen-sors in operation, sensors having the same characteristics. The creation of a single VC is intend-ing to offer many new possibilities for most application domains, in particular in the fields of monitoring and change detection. In this context, this paper describes the Copernicus Sen2Like software, a solution for harmonizing and fusing Landsat 8 / Landsat 9 data and Sentinel-2 data. The Copernicus Sen2Like software process a large collection of Level 1 / Level 2A products and generates highly qualified Level 2 Analysis Ready Data (ARD) products as part of an harmo-nized (Level 2H products) and/or fuzzed (Level 2F products) spatio-temporal dataset. For these purposes, we re-used and developed a broad spectrum of pre-processing / processing method-ologies including geometric co registration, atmospheric corrections, spectral co-registration, Bi-directional Reflectance Distribution Function (BRDF) corrections and up scaling to 10.0 meter for relevant Landsat bands. The Sen2Like software has been developed as a VC framework. It is therefore a convenient tool to compare processing algorithms together. It is also opportunity to appreciate efforts required to integrate a new mission such as spaceborne, airborne, uav mis-sions. The validation activities show that the proposed approach improves temporal consistency of multi temporal data stack and output products are interoperable with subsequent thematic analysis process. This software solution is based on free and open-source libraries and is public-ly available from https://github.com/senbox-org/sen2lik

Dishevelled stabilization by the ciliopathy protein Rpgrip1l is essential for planar cell polarity.

International audienceCilia are at the core of planar polarity cellular events in many systems. However, the molecular mechanisms by which they influence the polarization process are unclear. Here, we identify the function of the ciliopathy protein Rpgrip1l in planar polarity. In the mouse cochlea and in the zebrafish floor plate, Rpgrip1l was required for positioning the basal body along the planar polarity axis. Rpgrip1l was also essential for stabilizing dishevelled at the cilium base in the zebrafish floor plate and in mammalian renal cells. In rescue experiments, we showed that in the zebrafish floor plate the function of Rpgrip1l in planar polarity was mediated by dishevelled stabilization. In cultured cells, Rpgrip1l participated in a complex with inversin and nephrocystin-4, two ciliopathy proteins known to target dishevelled to the proteasome, and, in this complex, Rpgrip1l prevented dishevelled degradation. We thus uncover a ciliopathy protein complex that finely tunes dishevelled levels, thereby modulating planar cell polarity processes

The impact of methane leakage on the role of natural gas in the European energy transition

Abstract Decarbonising energy systems is a prevalent topic in the current literature on climate change mitigation, but the additional climate burden caused by methane emissions along the natural gas value chain is rarely discussed at the system level. Considering a two-basket greenhouse gas neutrality objective (both CO2 and methane), we model cost-optimal European energy transition pathways towards 2050. Our analysis shows that adoption of best available methane abatement technologies can entail an 80% reduction in methane leakage, limiting the additional environmental burden to 8% of direct CO2 emissions (vs. 35% today). We show that, while renewable energy sources are key drivers of climate neutrality, the role of natural gas strongly depends on actions to abate both associated CO2 and methane emissions. Moreover, clean hydrogen (produced mainly from renewables) can replace natural gas in a substantial proportion of its end-uses, satisfying nearly a quarter of final energy demand in a climate-neutral Europe

CHIME Level 2A and 2B: Atmospheric Correction and Higher-Level Processing

Challenge. CHIME (Copernicus Hyperspectral Imaging Mission for the Environment), planned to be launched in 2028, aims to complement the existing Copernicus satellites for observing land and coastal areas. The mission is synergetic with Sentinel-1, -2, -3 and LSTM, and also with other international hyperspectral missions such as SBG, EnMAP (by DLR) and PRISMA (by ASI). The imaging spectrometer covers the visible, near and shortwave infra-red spectral range from 400 nm to 2500 nm at intervals of at most 10 nm and at spatial resolutions of at most 30 m. These Earth observation capabilities will in particular support services for food security, agriculture and raw materials. Based on Top-Of-Atmosphere (TOA) radiances in cartographic or sensor geometry, Bottom-Of-Atmosphere (BOA) reflectance will be generated fulfilling the CEOS ARD surface and aquatic reflectance specifications. Also, a range of higher-level high priority products related to canopy and leaf level and soil and mineralogy will be provided. Methodology. CHIME Level 2A and 2B processors will be provided as open source and integrated in the Copernicus Expansion Mission Product Algorithms Laboratory (CEM-PAL) and for Level 2A in ESA’s operational processing environments for systematic product generation and distribution to users. The CHIME Level 2A processor will use several features of PACO (Python-based Atmospheric COrrection), duly optimized for CHIME, and optimized atmospheric corrections for land and water surfaces. First, it masks pixels, e.g. land-water, cloud-haze-cirrus-clear. It then derives atmospheric parameters based on mission-external Copernicus Atmosphere Monitoring Service (CAMS) and mission-internal instrument data. Next, it determines the reflectance for all types of terrain using the Copernicus DEM and based on Look-Up-Tables containing various atmospheric profiles and radiative transfers using libRadTran. Finally, the surface anisotropy quantified by Bidirectional Reflectance Distribution Function (BRDF) models is corrected. The CHIME Level 2B processor will apply well-established approaches for the retrieval of Canopy and Leaf Nitrogen and Water Content, Leaf Mass per Area for vegetated pixels, and Soil Organic Carbon (SOC) content and Kaolinite abundance for non-vegetated pixels. Due to the influence of cover fractions of green photosynthetic active vegetation (PV), dry non-photosynthetic vegetation (NPV) and bare soil per pixel, these will be estimated by an improved and tailored pixel masking. Results. To derive the atmospheric profile, air temperature and total ozone columns are extracted based on CAMS. Aerosol Optical Thickness (AOT) retrieval is based on dark reference areas in different wavelength ranges, e.g. 2100 nm, 660 nm, 470 nm for land and 850 nm, 660 nm for water, and especially in typical spectral relations. Water Vapour (WV) is estimated based on absorption regions at 945 nm, 1130 nm. Other molecular absorbers are expected to have constant mixing ratios. Vegetation products are based on a hybrid model blending the physics described by coupled canopy-leaf radiative transfers related to multiple states of vegetation characteristics and the efficiency of machine learning regression algorithms. For SOC content products, first dominant soil pixels are selected and then a SOC reference soil database is used for the parametrization of the machine learning retrieval model. For kaolinite abundance products, first kaolinite-bearing pixels are selected and then the kaolinite abundance and uncertainty are determined using machine learning techniques. The uncertainty analysis for the outputs considers the input uncertainties and uncertainty tree diagrams for the processing to account precisely for error contributors and to achieve consistency for Level 2A and 2B. Propagation is performed through analytical or Monte Carlo methods, depending on the applicability of assumptions on Gaussian probability distributions and linear measurement functions in the range of errors. Outlook for the future. L2H/F (harmonized / fused) extends Level 2A processing based on CHIME and SBG Level 1C products by considering co-registration to a reference image, inter-calibration, and spectral band adjustment, to obtain denser (and longer) time series. The realization of Level 2A and 2B processors will start by Q4/2023 and first prototypical versions are expected for Q4/2024 and Q2/2026, respectively, and final operational versions one year before CHIME satellite launch. In particular after launch, the Calibration and Validation (Cal/Val) of Level 2A and 2B products will extensively consider uncertainty information to ensure the mission performs within specified limits and to verify the accuracy of the derived products, usually by comparing it to a reference standard traceable to the International System of Units (SI) or to other internationally accepted standards and to independent ground-based measurements, e.g. RadCalNet and AERONET, or other mission products like NASA SBG and ESA TRUTH