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This paper discusses the process of validating active fire ‘yes/no’ binary fire detection products from moderate-resolution satellite sensors. General concepts and practical issues are illustrated by the validation of the Moderate Resolution Imaging Spectroradiometer (MODIS) active fire product in Siberia. Coincident Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery is used to characterize spatial patterns of flaming at sub-MODIS pixel scale. It is shown that for proper evaluation reference fire observations are needed at the scale of the satellite pixel, as only 60% of the MODIS footprints contain single contiguous clusters of ASTER fire pixels. In Siberia the size of a single ASTER fire cluster within the MODIS footprint that has a 50% probability of being flagged as ‘fire’ is ∼60, compared to ∼45 in the Brazilian Amazon, whereas previous radiative transfer simulations suggested similar detection probabilities. The lower-than-expected detection rates in Siberia are largely attributable to flaming underneath heavy smoke, which is not detected by the current MODIS algorithm. Pixel-based and cluster-based omission error rates are derived, and it is shown that the probability of flagging as ‘fire’ a MODIS pixel which contains a given number of 30-m ASTER fire pixels is typically 3–5 times lower than detecting a contiguous cluster with the same number of ASTER fire pixels. The procedures described are recommended for a consensus active fire validation protocol, but with the inclusion of multiplatform sensor configurations to complement the near-nadir angular sampling from single-platform observations such as MODIS and ASTER on Terra. [ABSTRACT FROM AUTHOR]

Abstract: Attitude dynamics of the first Russian nanosatellite TNS-0 is considered. The satellite is equipped with an attitude control system comprising a strong permanent magnet mounted along the satellite axis of symmetry and a number of hysteresis rods as a damper. It was expected that the satellite axis of symmetry traces the induction vector of the geomagnetic field. When the satellite has been orbited its angular momentum was unexpectedly high. To interpret motion of the satellite using mathematical study and flight data processing is the purpose of this paper. Three elementary sun sensors are installed on the satellite corp and their measurements analysis shows that the satellite angular velocity was decreasing with a time early in the mission. The analytical study of the motion is carried out. To examine the asymptotical stability of the motion the approximating model of the hysteresis was involved. Finally, the satellite probably reached the following motion: it rotates; the magnet direction precession-averaged follows the induction vector of the geomagnetic field; the angle between the magnet and the induction vector is not rather small and without tendency to be smaller. Actually, the satellite reached a permanent rotation mode almost without energy dissipation. Such a mode was mentioned in the 1960s and now it is explained and recognized in flight. [Copyright &y& Elsevier]

Abstract: This paper presents the results of a combined analysis of the experimental data of vertical- and oblique-incidence ionospheric sounding in the northeastern region of Russia and of the DMSP satellite data from 1999 to 2003. During geomagnetic disturbances period on ionograms we can see anomalous diffuse signals, which propagates outside great circle arc. The joint data analysis permits to suggest that the appearance of additional anomalous signals is connected with radio waves refraction in auroral oval and main ionospheric trough areas and with scattering on small-scale field-aligned irregularities close to auroral oval equatorial boundary in the region of electron diffuse precipitation. The basic attention is given to diagnostics of main ionospheric trough boundary and auroral oval zones position during geomagnetic disturbances periods. [Copyright &y& Elsevier]

Monitoring glacier changes in remote Arctic regions are strongly facilitated by satellite data. This is especially true for the Russian Arctic where recently increased optical and SAR satellite imagery (Landsat 8 OLI, Sentinel 1/2) and digital elevation models (TanDEM-X, ArcticDEM) are becoming available. These datasets offer new possibilities to create high-quality glacier inventories. Here, we present a new glacier inventory derived from a fusion of multi-source satellite data for Novaya Zemlya in the Russian Arctic. We mainly used Landsat 8 OLI data to automatically map glaciers with the band ratio method. Missing debris-covered glacier parts and misclassified lakes were manually corrected. Whereas perennial snow fields were a major obstacle in glacier identification, seasonal snow was identified and removed using Landsat 5 TM scenes from the year 1998. Drainage basins were derived semi-automatically using the ArcticDEM (gap-filled by the ASTER GDEM V2) and manually corrected using fringes from ALOS PALSAR. The new glacier inventory gives a glacierized area of 22,379 ± 246.2 km² with 1474 glacier entities >0.05 km². The region is dominated by large glaciers, as 909 glaciers <0.5 km² (62% by number) cover only 156 ± 1.7 km² or 0.7% of the area, whereas 49 glaciers >100 km² (3.3% by number) cover 18,724 ± 205.9 km² or 84%. In total, 41 glaciers are marine terminating covering an area of 16,063.7 ± 118.8 km². The mean elevation is 596 m for all glaciers in the study region (528 m in the northern part, 641 in the southern part). South-east (north-west) facing glaciers cover >35% (20%) of the area. For the smaller glaciers in the southern part we calculated an area loss of 3.4% (-52.5 ± 3.1 km²) from 2001 to 2016. [ABSTRACT FROM AUTHOR]

The article offers information on whether the Russian navigation satellite can help the accuracy of a survey, if its data is received and processed with global positioning system (GPS) data. It has been emphasized that utilizing more satellites in the sky will improve the accuracy, integrity and reliability of the receiver geographic positioning capability at any part of the world. The paper titled "GLONASS Goes Civil," which was published in the previous issue, discusses the announcement of Russian Defense Minister Sergei Ivanov to lift all precision restrictions on the Russian military-controlled Global Navigation Satellite System (GLONASS) for accurate and unlimited commercial use.

The article discusses the methods of estimating the anthropogenic heat fluxes in urban and industrial territories in Moscow, Russia . It explains the use of direct measurements of the heat fluxes, remote satellite measurements, and summing of all consumers of the heat and electric energy in the city for estimating anthropogenic heat flux in cities including Toulouse, Lodz, and Manchester. Moreover, a database on the energy consumption, population, and area of the largest urban agglomerations in Russia and in the world based on the analysis of the national statistical data were developed. Also cited is the idea of constructing the agglomeration circles comparable by their area with other megapolises and to focus on the administrative boundaries.