Question

Changes in reflectivity of visible light affect how much energy enters Earth's system. What term is used by scientists to describe the reflectivity of a surface? A. Contrastivity B. Libido C. Mirror-effect D. Alluvium E. Albedo

Short answer

E. Albedo

Step-by-step solution

- Understand the Question

The question is asking for the scientific term that describes the reflectivity of a surface, specifically in the context of how much energy from visible light enters Earth's system.

- Analyze Each Option

Review each of the given options to determine which one correctly matches the term for reflectivity of a surface.

- Contrastivity

Contrastivity sounds like it might refer to contrast, which is not related to the reflectivity of surfaces.

- Libido

Libido is a term related to sexual drive or desire and has no relevance to the reflectivity of surfaces.

- Mirror-effect

Mirror-effect might suggest reflectivity, but it is not the scientific term used to describe the reflectivity of a surface.

- Alluvium

Alluvium refers to sediment deposited by flowing water, and it has no connection to reflectivity.

- Albedo

Albedo is the scientific term that describes the reflectivity of a surface. It quantifies how much light that hits a surface is reflected without being absorbed. It is the correct answer.

Key concepts

Reflectivity

Reflectivity is a crucial concept when studying how light interacts with surfaces. It describes how much light is bounced off a surface and sent back into space, rather than being absorbed. This measure is essential in understanding the energy dynamics of Earth's system, as highly reflective surfaces, like ice and snow, can significantly influence global temperatures.

The term 'albedo' is often used to denote the reflectivity of a surface. A higher albedo means more light is reflected, and less is absorbed. This concept is vital for scientists studying climate change patterns.

For instance, if the albedo of Arctic ice decreases due to melting ice (replaced by darker ocean water), less sunlight is reflected, leading to more heat absorption. This can result in further warming and ice melting, creating a feedback loop called the ice-albedo positive feedback mechanism. It is important for students to grasp these principles for a better understanding of climate science.

Energy Balance

The energy balance of Earth is a delicate equilibrium between incoming energy from the Sun and the outgoing energy back into space. This balance determines Earth's climate and temperature.

Solar energy reaches Earth in the form of visible light and other electromagnetic radiation. Some of this energy is reflected back into space by clouds, atmospheric particles, and the Earth's surface (measured as albedo). The rest is absorbed, warming our planet. Earth then emits this absorbed energy as infrared radiation.

If Earth retains more energy than it emits, global temperatures rise. Conversely, if it emits more than it absorbs, temperatures drop. Factors affecting this balance include Earth's surface albedo, atmospheric composition, and cloud cover.

• High albedo surfaces like snow reflect more sunlight, cooling the Earth.
• Low albedo surfaces, like oceans and forests, absorb more sunlight, warming the Earth.

Understanding energy balance helps in predicting climate patterns and is pivotal in combating climate change.

Earth's System

Earth's system is a complex interplay of the atmosphere, lithosphere, hydrosphere, and biosphere. These components work together to sustain life and regulate the planet's environment.

The atmosphere involves layers of gases that protect life from harmful solar radiation and help regulate temperature. The lithosphere includes all solid ground, affecting geological activities and soil formation. The hydrosphere encompasses all water bodies, playing a critical role in energy transfer and supporting diverse ecosystems. Lastly, the biosphere represents all living organisms and their interactions with each other and their environments.

These systems are interdependent. For example, plant life (biosphere) absorbs carbon dioxide from the atmosphere and releases oxygen, affecting air quality and climate. Similarly, ocean currents (hydrosphere) distribute heat around the globe, influencing weather patterns and marine biodiversity.

Reflectivity (albedo) and energy balance are intertwined with these systems. Changes in one component, like deforestation (impacting the biosphere), can lead to increased atmospheric carbon dioxide, altering the energy balance and impacting the global climate. Understanding Earth's system helps in recognizing how human actions can lead to chain reactions affecting the planet's stability.