Phase line (cartography)
Encyclopedia
In cartography
, a phase line is a line to show some positional dependency or relation to the passage of time, most often changing phases of a military operation, or changing borders in histogeographic maps.
to refer to an imaginary line on a map used to coordinate phases of operations.
They are usually distinguished with different code names, varying by the particulars of the mission such as location and nature. By the same token, phase lines are frequently used after a battle or a military campaign
by historian
s to describe what territory was controlled by which side at a given phase of the campaign.
of the era such as the expansion of the Roman Empire
, the spread of Islam
or Christianity
. Other familiar phase line mapping most experience in late elementary or middle school classes would be the extent of various ice ages or the Ice Age
consequential shrinkage or extension of continental landmasses down the continental shelves as the results of such climate changes.
Cartography
Cartography is the study and practice of making maps. Combining science, aesthetics, and technique, cartography builds on the premise that reality can be modeled in ways that communicate spatial information effectively.The fundamental problems of traditional cartography are to:*Set the map's...
, a phase line is a line to show some positional dependency or relation to the passage of time, most often changing phases of a military operation, or changing borders in histogeographic maps.
Military usage
The term is also used in military terminologyMilitary terminology
Military terminology refers to the terms and language of military organizations and personnel as belonging to a discrete category, as distinguishable by their usage in military doctrine, as they serve to depoliticise, dehumanise, or otherwise abstract discussion about its operations from an actual...
to refer to an imaginary line on a map used to coordinate phases of operations.
They are usually distinguished with different code names, varying by the particulars of the mission such as location and nature. By the same token, phase lines are frequently used after a battle or a military campaign
Military campaign
In the military sciences, the term military campaign applies to large scale, long duration, significant military strategy plan incorporating a series of inter-related military operations or battles forming a distinct part of a larger conflict often called a war...
by historian
Historian
A historian is a person who studies and writes about the past and is regarded as an authority on it. Historians are concerned with the continuous, methodical narrative and research of past events as relating to the human race; as well as the study of all history in time. If the individual is...
s to describe what territory was controlled by which side at a given phase of the campaign.
Historical geography
Historical geographers use such techniques in a similar way, but written upon a longer time period. Dated phase lines on a map would indicate the growth or shrinkage of a great powerGreat power
A great power is a nation or state that has the ability to exert its influence on a global scale. Great powers characteristically possess military and economic strength and diplomatic and cultural influence which may cause small powers to consider the opinions of great powers before taking actions...
of the era such as the expansion of the Roman Empire
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....
, the spread of Islam
Islam
Islam . The most common are and . : Arabic pronunciation varies regionally. The first vowel ranges from ~~. The second vowel ranges from ~~~...
or Christianity
Christianity
Christianity is a monotheistic religion based on the life and teachings of Jesus as presented in canonical gospels and other New Testament writings...
. Other familiar phase line mapping most experience in late elementary or middle school classes would be the extent of various ice ages or the Ice Age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
consequential shrinkage or extension of continental landmasses down the continental shelves as the results of such climate changes.