hemisphere
Definition
A hemisphere is half of a sphere. The term hemisphere is often used to refer to the Earth's hemispheres, but it can also be used to refer to the hemispheres of other spheres, such as the moon or a planet.
The Earth's hemispheres are divided by imaginary lines called the equator and the prime meridian. The equator is an imaginary line that circles the Earth halfway between the North Pole and the South Pole. The prime meridian is an imaginary line that runs from the North Pole to the South Pole through Greenwich, England.
The Northern Hemisphere is the half of the Earth that is north of the equator. The Southern Hemisphere is the half of the Earth that is south of the equator. The prime meridian divides the Earth into the Eastern Hemisphere and the Western Hemisphere.
The Earth's hemispheres have different climates, vegetation, and animal life. The Northern Hemisphere is generally warmer than the Southern Hemisphere. The Northern Hemisphere also has more landmass than the Southern Hemisphere.
How can the word be used?
The Western Hemisphere is the half of the Earth that is west of the prime meridian.
Different forms of the word
Noun: hemisphere.
Adjective: hemispheric.
Adverb: hemispherically.
Etymology
The word "hemisphere" comes from the Greek words "hemi", meaning "half", and "sphaira", meaning "sphere". It was first used in English in the 16th century to describe one of the two halves of a sphere.
Question
What is a hemisphere?
AQA Science Exam Question and Answer
Question:
Explain the concept of a hemisphere and discuss how the Earth's hemispheres differ in terms of climate and seasons due to axial tilt.
Answer:
A hemisphere refers to half of a sphere or a circular object. In the context of Earth, there are two main hemispheres: the Northern Hemisphere and the Southern Hemisphere. The equator, an imaginary line circling the Earth horizontally, divides these hemispheres.
The Earth's hemispheres experience different climates and seasons due to their axial tilt. The axial tilt causes varying angles of sunlight to reach different parts of the planet at different times of the year. When one hemisphere is tilted toward the Sun, it experiences summer, characterised by longer days and warmer temperatures. Conversely, when tilted away, it undergoes winter, with shorter days and cooler temperatures.
For instance, during the Northern Hemisphere's summer, the Sun's rays strike this region more directly, resulting in warmer weather and longer days. At the same time, the Southern Hemisphere experiences winter, with shorter days and cooler temperatures. As Earth orbits the Sun, these conditions reverse, leading to opposite seasons in each hemisphere.
This hemispheric variation in climate and seasons influences weather patterns, ecosystems, and human activities. Understanding the Earth's hemispheres and axial tilt provides insights into the dynamic interactions between the Sun, Earth, and atmosphere, which shape our planet's diverse environments and contribute to the cycles of nature.