# An Overview of the Applications of Earth Observation Satellite Data: Impacts and Future Trends
## 1 Introduction  
Sustainable development and climate change are problems demanding prompt solutions, and solutions to both are essential to the present and future well-being of humanity [1, 2, 3]. Through the promotion of its Sustainable Development Agenda and the United Nations Framework Convention on Climate Change (UNFCCC), the United Nations aims to seek a sustainable development model for this generation and future generations and to achieve shared prosperity for people and the planet [2, 3]. The 2030 Agenda for Sustainable Development includes 169 aspirational targets and 232 global indicators for annualfollow-up and review. EO can provide direct measurements or indirect support for 71 (42%) of these targets and 30 (13%) of the indicators [4; 5]. At present, a significant gap remains before the Sustainable Development Goals (SDGs) can be achieved completely [3; 6]; Earth observation technology is a very effective and indispensable tool that can be used toward fulfilling the SDGs [4; 7; 8; 9; 10; 11; 12]. EO provides an effective way of exploring the physical, chemical, and biological information related to the Earth and of supporting the sustainable development of modern human civilization and the global environment by monitoring and assessing natural and artificial environmental conditions and changes [7; 13; 14]. EO satellites monitor the Earth's land, ocean, atmosphere, cryosphere, and carbon cycle from space in real-time and constantly transmit that information to the ground. The emerge of EO was promoted by the invention of the photography, and the first recorded EO image was captured by [PERSON] from a balloon in 1858. After that, various vehicles were used for EO such as kites and pigeons. The idea of using orbiting spacecraft to make observations of the ground was first explored by [PERSON] in his 1928 book, The Problem of Space Travel. Vanguard 2, designed by the United States Naval Research Laboratory, is the first satellite designed specifically for Earth observation to measure cloud cover distribution. Since then, many important EO satellites and sensors including Landsat, Advanced Very High-Resolution Radiometer (AVHRR), Moderate-resolution Imaging Spectroradiometer (MODIS), and Sentinel have been launched [15]. According to the database of the Committee on Earth Observation Satellites (CEOS), in October 2020, 327 EO satellite missions and 845 instruments were either currently operating or were planned for launch in the next 15 years--this database, however, is incomplete (CEOS has around 30 national space agencies as members). After more than 60 years of development, EO satellites have flourished. The significant advances in the spatial, spectral, and temporal resolution of remote sensing data brought about by improvements in remote sensing technology have dramatically changed how we observe the Earth [15]. Multi-spectral and hyper-spectral technologies, microwave radiometer, spaceborne radar, and synthetic aperture radar (SAR) as well as lasers on EO satellites now satisfy the needs of many types of research [16; 17; 18]. Additionally, as the costs of instruments and launching satellites have fallen, EO data have become more widely available. In addition to large multi-sensor platforms, the number of small satellites and unmanned aerial vehicles (UAVs) has exploded [18; 19]. Thus, in many ways, EO is positively affecting our lives. The information obtained by EO satellites is widely used in various research fields, especially in relation to the environment, where the measurements made by EO satellites are indispensable [19].