Planet Earth is a dynamic body, which is home to 7.8 billion people, and strong interactions exist between the human population and the Earth's different components (land, ocean, biosphere, cryosphere and atmosphere). The impacts of such interactions are observed from the day-today changes in weather, solar radiation, cloudy conditions, poor visibility, rainfall and frequency of natural hazards around the globe. The dynamic nature of the Earth is evident at the ocean coast through the ocean waves, the nature of these waves varies from day-today and also morning to evening. For example, the heights of waves can now be predicted through ocean modelling studies, which requires input from ground and satellite data. The Earth's components, the lithosphere, hydrosphere, cryosphere and biosphere, interact closely with the human population (Figure 1). As a result, changes may not be visualized on a day-today basis; however, short-and long-term changes can be observed by using various Earth-observation systems. Over the years, the Earth has become more complex, due to strong interactions between the various components of the Earth's systems and the influence of population living and interacting closely. Such interactions lead to degradation of the environment and to the depletion of resources, raise question of sustainability and pose a threat for our survival on Earth. This calls for the attention of all section of scientists to understand interaction, which is a challenging job in this complex system of systems. This also calls the attention of everyone on this Earth planet. The population is increasing, and the projection is that in the next three decades, the carrying capacity of the Earth will become saturated. We all learn how to take care of our babies, how to monitor their growth. We learn 'remote sensing' using 'cameras', to take daily, weekly, monthly and yearly photos and compare the changes of the baby. Similarly, scientists, use observations at different platforms to monitor various components of the Earth at spatial and temporal scales. Over the last three decades, different types of observing systems have been placed on the land and ocean around the globe; multi-sensor satellites orbit the globe. The observing systems provide real-time data, which are being used to forecast extreme weather events, cyclones/typhoons/hurricanes and other kinds of natural disaster that help to provide an alert to people who will be affected by an event. In the year 1900, the Galveston hurricane took lives of 10,000 people because there was no observing system (Singh, 2017). Now, the use of real-time data from observing system allow for people are evacuated, and lives are saved. Every year, many parts of the world suffer with extreme precipitation causing floods. People in the affected areas are trapped