How do the earth systems affect each other?
Earth systems affect each other by cause and effect. Like the biosphere producing more than usual co2 affecting the atmosphere.
How can an understanding of environmental science aid in handling natural disasters?
Understanding environmental science can help you handle natural disasters because you can avoid a tornado by staying in the geosphere.
What efforts can we make to create a sustainable future?
You can try to limit your co2 footprint. For example using reusable bags and, not plastic ones.