buys-ballot's law
Very low frequencyTechnical / Scientific
Definition
Meaning
A meteorological rule describing the relationship between wind direction and atmospheric pressure in the Northern Hemisphere.
A law stating that in the Northern Hemisphere, if you stand with your back to the wind, the atmospheric pressure is lower to your left; the reverse is true in the Southern Hemisphere. It's a practical application of the Coriolis effect and geostrophic wind balance for weather prediction.
Linguistics
Semantic Notes
This is a proper noun (a law named after the Dutch meteorologist Christophorus Buys Ballot). It refers to a specific, fixed principle, not a general concept. Use is almost exclusively within meteorology, oceanography, and navigation contexts.
Dialectal Variation
British vs American Usage
Differences
No differences in meaning or application. Spelling conventions for the possessive 's' may sometimes be omitted or presented differently (e.g., 'Buys Ballot Law'), but the core term is identical.
Connotations
Purely technical, with no regional connotative differences.
Frequency
Extremely rare in general discourse in both varieties. Slightly more likely to be encountered in British maritime or educational contexts due to historical navigation training.
Vocabulary
Collocations
Grammar
Valency Patterns
[Subject] follows/obeys Buys Ballot's law.Buys Ballot's law applies to [meteorological situation].One can deduce [pressure] from Buys Ballot's law.Vocabulary
Synonyms
Neutral
Weak
Usage
Context Usage
Business
Virtually never used.
Academic
Used in meteorology, physics, geography, and navigation textbooks and courses.
Everyday
Extremely rare; only in specific hobbies like sailing or storm chasing.
Technical
Primary context. Used by meteorologists, pilots, mariners, and climatologists to interpret weather maps and make short-term forecasts.
Examples
By Part of Speech
adjective
British English
- The Buys-Ballot principle is taught in navigation school.
- A Buys-Ballot-type relationship can be observed.
American English
- The Buys Ballot relationship is key to understanding cyclones.
- He made a Buys-Ballot-based prediction.
Examples
By CEFR Level
- Sailors sometimes use Buys Ballot's law to guess where a storm is.
- According to Buys Ballot's law, the low-pressure centre was north-west of our position, given the easterly wind.
- While geostrophic balance provides the theoretical foundation, Buys Ballot's law offers a readily applicable heuristic for mariners to locate pressure systems relative to their position.
Learning
Memory Aids
Mnemonic
Back to the Wind, Low to the Left (in the North). Think 'Buys Ballot's = Back to breeze, low left'.
Conceptual Metaphor
WIND IS A POINTER / PRESSURE IS A LANDSCAPE (The wind 'points' from high to low pressure, and you navigate this invisible landscape using the law).
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid direct translation of 'buys' as 'покупает'. It is a surname.
- The possessive 's' is part of the name, not indicating ownership. It is 'закон Бейс-Балло'.
- Do not confuse with Boyle's law (физика) or other scientific laws with similar structure.
Common Mistakes
- Misspelling: 'Buys Ballot Law', 'Buys-Ballot's Law', 'Buys Ballots Law'.
- Incorrect application to the Southern Hemisphere without reversal.
- Using it to describe wind speed instead of the pressure-direction relationship.
Practice
Quiz
Buys Ballot's law is primarily used in which field?
FAQ
Frequently Asked Questions
No, it is reversed. In the Southern Hemisphere, with your back to the wind, low pressure is to your right.
Christophorus Henricus Didericus Buys Ballot (1817–1890) was a Dutch chemist and meteorologist who formulated this law in 1857.
It is a reliable rule of thumb for large-scale weather systems but can be inaccurate near the equator (where the Coriolis effect is weak) or in complex, turbulent conditions.
The Coriolis effect is the physical phenomenon causing deflection of moving objects on a rotating planet. Buys Ballot's law is a practical, observational rule derived from the interplay of the Coriolis effect, pressure gradient force, and geostrophic wind.