Studies on site diversity to mitigate cloud blockage in satellite-ground optical communications based on long-term ground meteorological observation data [International Communications Satellite Systems Conference]

AbstractEvidences of an association between air pollution and Covid-19 infections are mixed and inconclusive. We conducted an ecological analysis at regional scale of long-term exposure to air-borne particle matter and spread of Covid-19 cases during the first wave of epidemics. Global air pollution and climate data were calculated from satellite earth observation data assimilated into numerical models at 10 km resolution. Main outcome was defined as the cumulative number of cases of Covid-19 in the 14 days following the date when > 10 cumulative cases were reported. Negative binomial mixed effect models were applied to estimate the associations between the outcome and long-term exposure to air pollution at the regional level (PM10, PM2.5), after adjusting for relevant regional and country level covariates and spatial correlation. In total we collected 237,749 Covid-19 cases from 730 regions, 63 countries and 5 continents at May 30, 2020. A 10 μg/m3 increase of pollution level was associated with 8.1% (95% CI 5.4%, 10.5%) and 11.5% (95% CI 7.8%, 14.9%) increases in the number of cases in a 14 days window, for PM2.5 and PM10 respectively. We found an association between Covid-19 cases and air pollution suggestive of a possible causal link among particulate matter levels and incidence of COVID-19.

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Evaluations of Surface PM10 Concentration and Chemical Compositions in MERRA-2 Aerosol Reanalysis over Central and Eastern China

Remote Sensing ◽

10.3390/rs13071317 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1317

Author(s):

Xiaodan Ma ◽

Peng Yan ◽

Tianliang Zhao ◽

Xiaofang Jia ◽

Jian Jiao ◽

...

Keyword(s):

Eastern China ◽

Mainland China ◽

Chemical Components ◽

Chemical Compositions ◽

Observation Data ◽

Causative Factors ◽

Routine Sampling ◽

Aerosol Compositions ◽

Modern Era

The chemical composition dataset of Aerosol Reanalysis of NASA’s Modern-Era Retrospective Analysis for Research and Application, version 2 (MERRAero) has not been thoroughly evaluated with observation data in mainland China due to the lack of long-term chemical components data. Using the 5-year data of PM10 mass concentrations and chemical compositions obtained from the routine sampling measurements at the World Meteorological Organization the Global Atmosphere Watch Programme regional background stations, Jing Sha (JS) and Lin’An (LA), in central and eastern China, we comprehensively evaluate the surface PM10 concentrations and chemical compositions such as sulfate (SO42−), organic carbon (OC) and black carbon (BC) derived from MERRAero. Overall, the concentrations of PM10, SO42−, OC and BC from the MERRAero agreed well with the measurements, despite a slight and consistent overestimation of BC concentrations and a moderate and persistent underestimation of PM10 concentrations throughout the study period. The MERRAero reanalysis of aerosol compositions performs better during the summertime than wintertime. By considering the nitrate particles in PM10 reconstruction, MERRAero performance can be significantly improved. The unreasonable seasonal variations of PM10 chemical compositions at station LA by MERRAero could be causative factors for the larger MERRAero discrepancies during 2016–2017 than the period of 2011–2013.

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Long-Term Observations of Beach Variability at Hasaki, Japan

Journal of Marine Science and Engineering ◽

10.3390/jmse8110871 ◽

2020 ◽

Vol 8 (11) ◽

pp. 871

Author(s):

Masayuki Banno ◽

Satoshi Nakamura ◽

Taichi Kosako ◽

Yasuyuki Nakagawa ◽

Shin-ichi Yanagishima ◽

...

Keyword(s):

Morphological Change ◽

High Frequency ◽

Climate Changes ◽

Wave Climate ◽

Time Interval ◽

Observation Data ◽

Beach Profile ◽

Water Level Variations ◽

Monthly Variations

Long-term beach observation data for several decades are essential to validate beach morphodynamic models that are used to predict coastal responses to sea-level rise and wave climate changes. At the Hasaki coast, Japan, the beach profile has been measured for 34 years at a daily to weekly time interval. This beach morphological dataset is one of the longest and most high-frequency measurements of the beach morphological change worldwide. The profile data, with more than 6800 records, reflect short- to long-term beach morphological change, showing coastal dune development, foreshore morphological change and longshore bar movement. We investigated the temporal beach variability from the decadal and monthly variations in elevation. Extremely high waves and tidal anomalies from an extratropical cyclone caused a significant change in the long-term bar behavior and foreshore slope. The berm and bar variability were also affected by seasonal wave and water level variations. The variabilities identified here from the long-term observations contribute to our understanding of various coastal phenomena.

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Using Long-Term Earth Observation Data to Reveal the Factors Contributing to the Early 2020 Desert Locust Upsurge and the Resulting Vegetation Loss

Remote Sensing ◽

10.3390/rs13040680 ◽

2021 ◽

Vol 13 (4) ◽

pp. 680

Author(s):

Lei Wang ◽

Wen Zhuo ◽

Zhifang Pei ◽

Xingyuan Tong ◽

Wei Han ◽

...

Keyword(s):

Soil Moisture ◽

Land Surface ◽

Arabian Peninsula ◽

Vegetation Coverage ◽

Observation Data ◽

Desert Locust ◽

Meteorological Observations ◽

Earth Observation Data ◽

Vegetation Loss

Massive desert locust swarms have been threatening and devouring natural vegetation and agricultural crops in East Africa and West Asia since 2019, and the event developed into a rare and globally concerning locust upsurge in early 2020. The breeding, maturation, concentration and migration of locusts rely on appropriate environmental factors, mainly precipitation, temperature, vegetation coverage and land-surface soil moisture. Remotely sensed images and long-term meteorological observations across the desert locust invasion area were analyzed to explore the complex drivers, vegetation losses and growing trends during the locust upsurge in this study. The results revealed that (1) the intense precipitation events in the Arabian Peninsula during 2018 provided suitable soil moisture and lush vegetation, thus promoting locust breeding, multiplication and gregarization; (2) the regions affected by the heavy rainfall in 2019 shifted from the Arabian Peninsula to West Asia and Northeast Africa, thus driving the vast locust swarms migrating into those regions and causing enormous vegetation loss; (3) the soil moisture and NDVI anomalies corresponded well with the locust swarm movements; and (4) there was a low chance the eastwardly migrating locust swarms would fly into the Indochina Peninsula and Southwest China.

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PROCEDURE OF CALCULATING THE REDUCED COSTS FOR DESIGNING A COMBINED LOW-ORBIT SATELLITE SYSTEM

International scientific journal Internauka Series Economical Sciences ◽

10.25313/2520-2294-2021-3-7015 ◽

2017 ◽

Author(s):

Vitaly Pochernyaev ◽

◽

Tetiana Kadatska ◽

Keyword(s):

Satellite System ◽

Observation Data ◽

Satellite Systems ◽

Capital Costs ◽

Ground Segment ◽

Rocket Carrier ◽

Approximate Cost ◽

Main Component ◽

The Cost ◽

Space Segment

The article provides a method for calculating the costs when designing a promising embodiment of a low-bit satellite system. For Ukraine, the prospects for this option lies in the fact that their own means of achieving a large number of satellites in orbit are applied. At the same time, satellites are multifunctional and used to organize communication and broadcasting, the sounding of the atmosphere and the surface of the Earth, subsurface locations, cosmic observation, data collection from the Internet sensors. The space group consists of mini, macro-, nanosterans, which are delivered to the orbit of a domestic rocket carrier into orbit. The technical and economic efficiency of the satellite system lies not only in the above advantages, but also in its hierarchical construction - combination of the root satellite, ministerial repeater, macrovers. The article provides an analysis of other low-bit satellite systems. A feature of the study of the combined LEO is the fact that the proposed construction of the satellite system allows the use of technological distributed registries as one of the through digital technologies. In digital transformation of the economy, the technology of distributed registers plays the same role as Internet things, cloud computing, 5G and Big Data technologies. The method of calculating the presented costs is to calculate the cost of the development, production and operation of the system at the stage of its design. The costs of developing space and ground segments are included in the total capital costs. The costs of developing a space segment are highlighted on the cost of developing a root satellite, a minivan-repeater, microscope. The same approach is also laid for the cost of exploitation of the space segment. When calculating the costs of the ground segment as the main component of earth stations, antenna systems, radio transmission microwaves and radio receiving microwaves, information processing devices, terminal equipment are taken as the main components of earth stations. The approximate cost of serial production of root sieuine, mini satellite, retrograder, microsatellite is indicated. The estimated cost of one minute of access in the studied combined LEO and in the existing "close" to the appointment of a low-bit satellite system is given.

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Technical Considerations for Modernizing Nova Scotia’s Coordinate Referencing System

GEOMATICA ◽

10.5623/cig2016-201 ◽

2016 ◽

Vol 70 (2) ◽

pp. 85-96 ◽

Cited By ~ 1

Author(s):

Jason Bond

Keyword(s):

Passive Control ◽

Global Navigation Satellite Systems ◽

Observation Data ◽

Crowd Sourcing ◽

Satellite Systems ◽

Network Location ◽

Land Administration ◽

New Strategy ◽

Global Navigation Satellite ◽

Technical Considerations

The Nova Scotia Coordinate Referencing System (NSCRS) is Nova Scotia's current framework for providing location-based information. The NSCRS is the foundation for the province's geographic data, includ ing the land administration system. In 2012, the province began developing a modernization strategy to better execute its coordinate referencing program to address ongoing accuracy and accessibility needs. A net work of active control stations (ACSs) tracking global navigation satellite systems (GNSS) is at the core of the new strategy. In addition to providing better accuracy and accessibility to the NSCRS, the tech nol ogy has created new opportunities to sustain its passive control infrastructure. In 2015, the installation of 40 ACSs across the province was completed, providing industry with access to real-time, centimetre-level positioning. Over the course of the NSCRS modernization project, several tech nical considerations needed to be addressed pertaining to the design of the network, location of the ACSs, flow of the ACS data and the crowd sourcing of GNSS observation data to maintain the passive con trol sys tem. These technical considerations are reviewed and the solutions implemented to address the needs of this initiative are presented.

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A SLR Pre-Processing Algorithm Based on Satellite Signature Effect

Applied Sciences ◽

10.3390/app11198880 ◽

2021 ◽

Vol 11 (19) ◽

pp. 8880

Author(s):

Bowen Guan ◽

Cunbo Fan ◽

Ning An ◽

Ricardo Cesar Podesta ◽

Dra Ana Pacheco ◽

...

Keyword(s):

Mean Value ◽

Observation Data ◽

Short Term ◽

Error Sources ◽

Effect Model ◽

The Mean ◽

The Stability ◽

First Time ◽

Satellite Signature Effect

As one of the major error sources, satellite signature effect should be reduced or even erased from the distribution of the post-fit residuals to improve the ranging precision. A simulation of satellite signature effect removal process for normal point algorithm is conducted based on a revised model of satellite response, which fully considers the structural and distribution characteristics of retroreflectors. In order to eliminate both long-term and short-term satellite signature effect, a clipping method for SLR data processing is proposed by defining the clipping location as 5.6 mm away from the mean value of the long-term fit residuals to select effective returns for normal points. The results indicate that, compared to normal points algorithm, the RMS per NP of LAGEOS-1 observation data processed by the clipping method is reduced from 62.90 ± 9.9 mm to 56.07 ± 4.69 mm, and the stability of RMS is improved 53%. This study improves the satellite signature effect model and simulates the fluctuation of normal points caused by satellite signature effect for the first time. The new method based on the simulation of satellite signature effect has stronger robustness and applicability, which can further minimize the influence of satellite signature effect on the SLR production and significantly improve the data property.

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Bird trends from long-term observation data at sites in the Hudson Bay Lowlands

Avian Conservation and Ecology ◽

10.5751/ace-01821-160110 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Rodney W. Brook ◽

Lisa A. Pollock ◽

Kenneth F. Abraham ◽

Glen S. Brown

Keyword(s):

Hudson Bay ◽

Observation Data ◽

Hudson Bay Lowlands ◽

Long Term Observation

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Analysis of the Effect of Different Combinations of Observation Satellites on the Resolving Accuracy of GNSS Observation Data

E3S Web of Conferences ◽

10.1051/e3sconf/202020603025 ◽

2020 ◽

Vol 206 ◽

pp. 03025

Author(s):

Junze Wang ◽

Maohua Yao ◽

Wenting Zhou ◽

Xiangping Chen

Keyword(s):

Measurement Accuracy ◽

Control Point ◽

Satellite System ◽

Base Stations ◽

Observation Data ◽

Control Points ◽

Level Control ◽

Satellite Systems ◽

Beidou Navigation Satellite System ◽

Stable Measurement

In this paper, 24 C-level control points under different terrain conditions were selected to be the testing points. The binary-satellite system (GPS+GLONASS) and the triple-satellite system with BeiDou Navigation Satellite System (BDS) (BDS+GPS+GLONASS) were adopted for static measurement; and the observation data from BeiDou Ground-based Augumentation System (GBAS) base stations in Guangxi were collected for solution. By comparing the residuals of GPS tri-dimensional baseline vectors and the internal accord accuracy of each control point under the binary and triple-satellite systems, the effect of data collected by different satellite systems under different terrain conditions on measurement accuracy was studied. According to the results, (1) the triple-satellite system with BDS showed more stable measurement accuracy; (2) in plane, the two systems were of equivalent measurement accuracy in mountainous and flat areas; in elevation, the triple-satellite system showed higher and more stable measurement accuracy.

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