Issledovanie Zemli iz Kosmosa

Enhanced wind-driven water upwelling was observed off the north-west coast of the Japan Sea in the summer of 2022. The upwelling index calculation showed that the coastal upwelling was induced by offshore Ekman transport. The offshore transport is largely controlled by mesoscale processes, involving mesoscale eddies and filaments. Based on the multisatellite and meteorological data sets our results provide opportunity to observe the upwelling response to the strong Typhoon Hinnamnor (September 2022). The typhoon resulted in the separation of the upwelling core from the coast and subsequent advective transport of cold waters toward the deep part of the northern Japan Sea. The intensification of advection was determined by the interaction of upwelling waters with the mesoscale anticyclonic meander of the Tsushima Current. Under the influence of strong winds of typhoon, a sharp temperature decrease in upwelling filaments was observed. The typhoon increased upwelling in the western shelf region of the Tartar Strait. In September 2022 coastal upwelling resulted in the formation of a negative surface temperature anomaly in the northern part of the Japan Sea.

Spatiotemporal distribution of sulfur dioxide content during the strong 2019 Raikoke stratovolcano eruption was studied using satellite data. The total mass of SO₂ emitted at an altitude of 15 km was determined. The influence of stratospheric aerosols on the Earth’s ozone layer was assessed, and changes in ozone content in the atmospheric column were detected based on the analysis of multiannual time series of aerosol optical depth change. The values of aerosol optical depth increased (up to 2.3), which was related to the active transformation of sulfur dioxide into the sulfuric acid and the generation of sulfate aerosols. A sharp decrease in ozone content (by 73 DU) was detected after the end of volcanic activity, which was followed by a significant decrease in temperatures in the stratosphere (by 8–17°C). It was found that increased values of the extracted mass of SO₂ persisted for several days after the eruption and then decreased exponentially with time. Changes in the total ozone content in the atmospheric column were consistent with variations in temperatures in the stratosphere.

To improve climatic conditions, preserve agricultural yields and protect against deflation, 8 state protective forest belts (SPFB), with a total length of 5320 km, were designed 76 years ago. Currently, current data on the state of forest protection areas are not publicly available, so determining the current state of protective forest belts based on remote sensing data is relevant. The purpose of the study is to determine the main changes in the spectral brightness coefficients (SBC) of the predominant rocks at the Penza-Kamensk State Forestry Plant based on remote sensing data and inventory work carried out. The object of the study is the state protective forest belt “Penza-Kamensk”, which runs through the territory of the Volgograd region. Mapping of the design boundaries of the research object was carried out using ultra-high-resolution data. The determination of the safety of the Penza-Kamensk State Forestry Landscape was carried out using high-resolution data from the Sentinel-2 satellite based on the NDVI vegetation index). When performing desk research, 6949.62 hectares of the project area of the state protective forest belt were allocated, the area inside the contours was 6317.91 hectares, and the overall safety of the studied object was 90.91%. During the inventory work, more than 59 different types of combinations were described to determine the tree-species composition, the average height of the plantings was calculated, the density in the plots was calculated, and quality classes were assigned according to the Orlov table. As a result of the inventory, it was determined that the predominant species are: English oak (Quercus robur L.), Pennsylvania ash (Fraxinus pennsylvanica Marshall) and Elm (Ulmus L.), for which the CFC was calculated. The data obtained demonstrate a significant difference between the coefficients of the predominant tree species from channel 6 to 8A; high values are observed in sections with a pure elm species composition and a mixed composition. The minimum indicators of CSI in the analysis were obtained in areas with pure ash stands.

This work is focused on georeferencing of the measurements data of the Russian MTVZA-GYa scanner/sounder, installed on board the “Meteor-M” No. 2–3 spacecraft. This instrument was put into operation in August 2023 and continues to operate normally at present. The failure of the spacecraft’s centimeter communication line in October 2023 significantly reduced the coverage area of MTVZA-GYa measurements. Currently, it is limited to direct visibility of the satellite by ground-based receiving stations. The absence of all-season clear boundaries of the “sea/land surface” transition in the observation area makes it impossible to assess the quality and correct the georeference of MTVZA-GYa measurements. In this regard, within the framework of the presented paper, measurement data with global coverage over the globe, carried out by this instrument in August-September 2023, were analyzed. Based on positive experience with previous versions of MTVZA’s instruments, the authors used similar methods for assessing the georeferencing quality and searching for angles that correct it. At the same time, the existing design differences of the sample device under consideration (changed scanning directions, changed observation sectors) required some changes to be made to the algorithm for implementing georeferencing. Research has shown that the optical axes of this instrument, corresponding to individual groups of frequency channels, have different orientations. In this regard, the search for georeferencing-correcting angles was performed for each group separately. During performing a differentiated approach to georeferencing different groups of frequency channels using the found values of corrective roll, pitch and yaw angles, the authors managed to achieve the following accuracy indicators: for a group of channels 10.6–23.8 GHz – (4.59 ± 8.22) km; for a group of channels 31.5–48.0 GHz – (5.51 ± 8.83) km; for a group of channels 52 – 91.65 GHz – (8.03 ± 11.69) km.

This paper analyzes the impact of changes in surface wind (SW) speed and direction in the northern and southern parts of the Chilean upwelling (CA) on the interannual and interdecadal variability of the Ekman upwelling index. Satellite data were used for the period 1988 – 2022’s. It is shown that the increase in wind speed in the northern part of the CA region during 1997–2004 was mainly accompanied by the change in the direction of SW in the coastal zone which favors the upwelling intensification. For other periods (with the exception of certain years) this pattern was not case. In general, wind speed changes in the northern part of the CA region impact a little bit more effectively the changes in the upwelling index than changes in the SW direction. In the southern CA part, the change in the Ekman upwelling index is mostly determined by the change in the SW speed. Long-term variability of wind speed in the upwelling zone is realized in the form of a multidecadal oscillation, the period of which is estimated at 65-70 years which coincides with the typical period of the Atlantic multidecadal oscillation.