Layers of the Atmosphere

Front

Atmosphere Noun

---

[at-mo-sfeer]

Back

Atmosphere

---

The entire envelope of gases surrounding the Earth, divided into distinct layers based on temperature and composition.

---

Example: This diagram shows the five main layers of Earth's atmosphere, ordered by altitude, with key characteristics like temperature and common phenomena for each layer.

Front

Troposphere Noun

---

[troh-po-sfeer]

Back

Troposphere

---

The lowest layer of Earth's atmosphere, where weather occurs and temperature generally decreases with an increase in altitude.

---

Example: This diagram shows the Troposphere is the lowest layer of Earth's atmosphere, extending from the surface to about 12 km, where airplanes fly and weather happens.

Front

Stratosphere Noun

---

[strat-o-sfeer]

Back

Stratosphere

---

The atmospheric layer above the troposphere that contains the ozone layer and where temperature increases with altitude.

---

Example: This diagram shows the Stratosphere as the second layer of the atmosphere, located above the Troposphere, where supersonic jets and stratospheric balloons fly.

Front

Mesosphere Noun

---

[mes-o-sfeer]

Back

Mesosphere

---

The middle layer of the atmosphere, known as the coldest layer, where most meteors burn up upon entry.

---

Example: This diagram shows the Mesosphere as the layer of the atmosphere above the Stratosphere, where meteors burn up upon entering from space.

Front

Thermosphere Noun

---

[thur-mo-sfeer]

Back

Thermosphere

---

The hottest and uppermost layer of the atmosphere, which contains the ionosphere and where auroras are frequently observed.

---

Example: This diagram shows the Thermosphere's location and altitude (50-400 km) relative to the other layers of Earth's atmosphere, starting from the ground up.

Front

Exosphere Noun

---

[ek-so-sfeer]

Back

Exosphere

---

The outermost region of the atmosphere that gradually fades into the vacuum of space, containing very few particles.

---

Example: This diagram shows the Exosphere as the final, outermost layer of Earth's atmosphere, where the atmosphere thins out and merges with outer space.

Front

Ozone Layer Noun

---

[oh-zone lay-er]

Back

Ozone Layer

---

A region of high ozone concentration within the stratosphere that absorbs the majority of the sun's harmful ultraviolet radiation.

---

Example: This diagram shows the ozone layer surrounding Earth and how it protects the planet by blocking most of the sun's harmful ultraviolet (UV) radiation.

Front

Ionosphere Noun

---

[ahy-on-o-sfeer]

Back

Ionosphere

---

A region of charged particles within the thermosphere that can reflect radio waves, enabling long-distance communication.

---

Example: This diagram shows the main layers of Earth's atmosphere and highlights the Ionosphere, a region in the upper atmosphere that overlaps several other layers.

Front

Altitude Noun

---

[al-ti-tood]

Back

Altitude

---

The height of an object or point in relation to sea level or ground level, a key factor in atmospheric properties.

---

Example: This diagram shows that as altitude (height) increases from sea level to a mountain top, the air becomes less dense, causing atmospheric pressure to decrease.

Front

Air Pressure Noun

---

[air presh-er]

Back

Air Pressure

---

The force exerted onto a surface by the weight of the air in the atmosphere, which decreases with increasing altitude.

---

Example: This image shows that air pressure is higher at lower altitudes because there are more air molecules above, and lower at higher altitudes with fewer molecules.