Definition

Noun: 1. A line on a map connecting points of equal atmospheric pressure: In meteorology, an isobar is a line drawn on a weather map that links locations with the same barometric pressure at a specific time. These lines are crucial for visualizing pressure patterns, which help in forecasting wind and weather. 2. (Chemistry) One of two or more atoms of different chemical elements that have the same atomic mass number: In nuclear physics and chemistry, an isobar is any of a group of nuclides (atoms) of different elements that share the same total number of protons and neutrons (mass number, A) but have different numbers of protons (atomic number, Z).

Examples of Usage

• Meteorology:
  • The weather map showed a series of tightly packed isobars, indicating strong winds.
  • Meteorologists analyze the spacing of isobars to predict wind speed and direction.
• Chemistry/Physics:
  • Carbon-14 and Nitrogen-14 are isobars, as both have a mass number of 14.
  • The study of nuclear stability often involves comparing different isobars.

Advanced Usage

• "Isobaric" (Adjective): Pertaining to or characterized by constant pressure.
  • An isobaric process in thermodynamics is one where the pressure remains constant.
• "Isobaric surface": A surface in the atmosphere where the pressure is the same at every point.
  • Weather balloons measure conditions on various isobaric surfaces.

Variants and Related Words

• Isobaric (adj): Relating to equal pressure or to isobars.
• Isobarism (n, rare): The state or condition of being isobaric.
• Isogram / Isopleth (n): A more general term for a line on a map connecting points of equal value (e.g., isotherm for temperature, isobar for pressure).

Synonyms

• Meteorology: Pressure contour, isopleth (specifically for pressure).
• Chemistry: None are perfect synonyms, but related terms include nuclide (a type of atom) and isotone (atoms with the same number of neutrons).

Related Phrases

• "To draw/follow an isobar": To plot or trace a line of equal pressure on a map.
  • The student learned to draw an isobar by connecting all the 1013-millibar stations.
• "A family of isobars": In chemistry, a group of nuclides with the same mass number.
  • The chart displayed the entire family of isobars for mass number 40.

Noun

1. (meteorology)an isogram connecting points having equal barometric pressure at a given time