The sphere that caused an event depends on the specific event in question, as Earth's system consists of four interconnected spheres: the lithosphere (land/rock), atmosphere (air), hydrosphere (water), and biosphere (living things). An event can be caused by changes or interactions in one or more of these spheres. For example:

• A volcanic eruption originates from the lithosphere.
• A hurricane is caused by atmospheric conditions.
• A flood involves the hydrosphere.
• A forest fire may involve the biosphere.

Events often result from interactions among these spheres, and one sphere's change can trigger effects in others. For instance, a volcanic eruption (lithosphere) releases particles into the atmosphere, which can affect the hydrosphere (rainfall) and biosphere (plant growth)

. Therefore, identifying which sphere caused an event requires knowing the nature of the event itself, as events are typically linked to one or more of Earth's spheres acting or interacting