Sea ice plays a major role in our planet’s climate. It’ acts as a reflector of solar energy, mainly in spring and summer. Sea ice covered with fresh snow can reflect 75-90% of solar energy, the open sea reflects just 5-15%. Sea ice acts as an insulator in autumn and winter. This insulating effect limits the amount of both heat and moisture the ocean loses to the atmosphere. The declining sea ice disrupts the climate, societies and fauna of Polar areas, but encourages the econcmic and industrial development. The relevance of this study is related to current trends in the use of remote sensing in solving problems of a different nature in environmental monitoring. The sea ice was analyzed and mapped according to the European Space Agency data (ESA), acquired by sensors of Sentinel-1 SAR (Synthetic Aperture Radar), Sentinel- 2MSI (Multi Spectral Instrument), Sentinel- 3 and GIS. The subject of the study is to demonstrate the dynamics, during the summer season from 2015 to 2019, around the coastline of Livingston Island, New Shetland Islands in Antarctica and Longyearbyen in the Arctic. Changes in environmental objects are indicated by radar images through different processing approaches. The results clearly show that sea ice melting can be best recorded by using SAR data through the C-band. The results obtained are data in the form of thematic maps showing the spatial reflectance of sea ice and its dynamics over time.
Climate components are closely related to one of the most dynamic elements of the Earth's surface, such as wet snow. It is an element which influences most of the flood-related models. The subject of the research is a specific event registered on 10/07/2018 in Urupema, the wet snow, which remained for only a few days. Urupema is a Brazilian city with an average annual temperature of 13C, located in the southern part of Santa Catarina and heavy winters regularly bring frost, snow and frozen water in the area.The aim of the study is to demonstrate different approaches for short-lived snow coverage monitoring based on SAR and optical satellite data. The subject of the study is to demonstrate the dynamics for a short period of time. The results obtained are data in the form of thematic maps showing the spatial reflectance of wet snow and its dynamics over time. A methodology based on SAR and optical satellite data for wet snow exploration has been developed. The methodology was applied to the city of Urupema. Brazil includes a wide range of meteorological conditions on a large area and diversified relief, which is why there is no optical data with good quality. This requires the use of SAR data that has the advantage over the visible and NIR ranges. Various spectral indices and indicators, calculated on a Sentinel database in Copernicus have been used. Results have been obtained for the dynamics of the particular region over a given time period.
Data-driven innovations bring significant benefits to societies directly affected by global warming, as they underpin Global and European climate change policy. The application of a synchronous approach and interoperability of data from different sources for environmental monitoring in one of the most vulnerable to climate change regions in the world is the aim of this research. The research was conducted at Hannah Point peninsula, near the Bulgarian Antarctic base "St. Kliment Ohridski" on Livingstone Island, South Shetland Islands, Antarctica. The study area has high ecological importance for tracking the dynamics of processes not only on a local but also on a global scale. Various research sites with different groups of objects serving as environmental benchmarks were selected to be studied. The study objects include snow cover, wet snow, water, ice (including sea ice), herbaceous vegetation, lichens, mosses, soils, and sand. For each of the objects, ground GPS points were defined and in situ spectrometric measurements were performed. Data from an innovative Automatic recording Weather Station (AWG), as well as various indicators and indices based on the spectral reflectance characteristics of the investigated objects in the optical and microwave range, were used. For their generation were used satellite images from Sentinel-1 and Sentinel-2 sensors of European Space Agency. Multiple optical indices were used to demonstrate the changes in the state of the objects for the summer season of 2022-2023. The data obtained and models used will serve the Bulgarian initiative for the construction of the Digital Twins, which is being on pilot developed in the Department of Aerospace Information (SRTI-BAS) and could be used by a wide range of scientists in the field of polar research as well as for climate change education. Open Data were used in this study, to promote the open science policy and FAIR principles as much as possible.
The present work traces the development of an illegal landfill near the town of Svoge in Bulgaria. After 2016, a waste management plan is prepared on the territory of the municipality and a decision is made to dispose of it by depositing it in a regional landfill for municipal waste in the town of Kostinbrod. The aim of the study is to trace the development of biochemical processes that took place on the territory of the former landfill and whether their impact continues to this day. Data from the Open Data Portal (https://data.egov.bg/), the National Spatial Data Portal INSPIRE (https://inspire.egov.bg/bg), satellite data and GIS, several spectral profiles and indices such as Normalized difference vegetation index (NDVI), Tasseled Cap Transformation (TCT) were used. Composite images from the multispectral instrument (MSI) of the Sentinel 2 platform and radar (SAR) from the Sentinel 1 platform of the Copernicus program of the European Space Agency were used. The surface temperature of the landfill was calculated using the heat channels from the Landsat 5-7 (ETM) and Landsat 8 and Landsat 9 (OLI / TIRS) sensors. A combination of radar and optical data was made. Data from different seasons and years were used in order to monitor the dynamics of thermal pollution in the study area. Quantitative and qualitative assessment of the territory on which the landfill is located has been made. Last but not least, the role of high-value open data in environmental monitoring has been demonstrated, which will reduce the administrative burden of making responsible decisions for each smaller municipality and will be successfully implemented in future methodologies for improving Digital twins through technical work in Destination Earth (DestinE) and information about any point, area or globally significant territories.
Snow cover monitoring shows the great importance of this rainfall, the time-lines of the data from this event, and the spatial range and area of the observed object. The main aim of the presented research is to trace the use of different satellite data and approaches to track the dynamics of the development of the short-lived snow coverage. The subject of the study is short-lived snow coverage and its dynamics for 12 and 13 March 13, 2017 for Sofia city area, Bulgaria. The objects were analyzed and mapped according to ESA data, acquired by sensors Sentinel-1 SAR and Sentinel-2 MSI. Results have been obtained for quantitative changes of wet snow cover and its dynamics. The data used are with a high time-spatial resolution, which is imperative when it is need to study a short-lived event such as the wet snow coverage. The importance of this monitoring is that the remote sensing and reliable data required calculating models of climate, natural disasters and crashes have been obtained.
One of the main issues that concerns mankind today is the problem of domestic waste and how it affects climate change, air pollution and the environment. In the present work the heat pollution from the waste disposal site is tracked at various time points. The waste disposal site near Vidin was selected for the purpose of the research. Optical satellite data from the Sentinel 2 multi-spectral instrument (MSI) and synthetic – aperture radar (SAR) data from the Sentinel 1 platform of the Copernicus program of the European Space Agency were used. The Landsat 5 -7 (ETM) and Landsat 8 (OLI / TIRS) sensors were used to calculate the surface thermal pollution of the waste disposal sites. Orthogonalization of satellite imagery was made to trace the dynamics of the main components of the Earth's surface - vegetation, moisture and soil. On this basis, a correlation is made to trace the link between the different components of the Earth's surface at different time points. Climate data on average air temperature, evapotranspiration, radiation and rainfall was used and a comparative analysis of surface temperature from landfill and climatic data was made.
