So you want to abolish time zones (2015)

Original Article ↗ Hacker News Discussion ↗

A proposal to abolish time zones and put the world on a single UTC-based clock highlights tension between technical simplicity and everyday social reality. Commenters largely agree that standardizing on UTC for servers and software is beneficial, but argue that removing local time zones would badly misalign clock time with daylight, disrupt social and legal norms, and simply replace time-zone lookups with more complex “when are people actually awake or working there?” questions. Abolishing daylight saving time is widely seen as a safer, more practical reform, though opinions diverge on whether permanent “winter time” or “summer time” would be better.

Daylight Saving Time vs. Standard Time

  • Many consider abolishing DST “very safe” and beneficial for health and simplicity; several regions that dropped it report few issues.
  • Debate over permanent standard vs permanent summer time:
    • Scientists are said to strongly favor year‑round standard time.
    • Some at higher latitudes value summer time for light evenings; others argue early morning light and safety (school/commute) matter more.
    • Prior experiments with permanent summer time quickly became unpopular.

Arguments For a Single Global Time (UTC Only)

  • Proponents say:
    • It removes timezone math for events, flights, and cross‑border coordination.
    • One universal timestamp avoids “is this Eastern/Central/local?” ambiguity.
    • People already adapt to UTC in some online games and technical work.
    • Tools could answer “when is a good time to call?” directly, factoring in culture, daylight, and business hours.
  • Some argue timezones mostly rephrase an underlying problem (availability) and that simplifying the model benefits everyone, not just programmers.

Arguments Against Abolishing Time Zones

  • Critics say it just relocates complexity:
    • You still must learn “awake/business hours” for each place instead of offsets.
    • People reason about time relative to the Sun; decoupling clocks from day/night would push them to informal local times, effectively creating countless ad‑hoc “shadow timezones.”
  • Concerns about splitting local days across calendar dates, complicating language like “today,” religious/secular law, and everyday scheduling.
  • Real‑world resistance is expected: examples include unofficial local time in western China and factory staff rejecting visible UTC clocks.

Alternative Schemes

  • Proposals include infinite/local solar time zones, per‑person “published hours,” or smoothly varying “continuous time.”
  • Opponents argue highly granular local time is worse: small distance ≈ minutes of difference, buses and events need minute‑level precision, and would rely heavily on GPS and software.

Software and Data Engineering Practices

  • Broad agreement on technical best practices:
    • Run servers on UTC; store timestamps as UTC plus a timezone identifier.
    • Use standard libraries and up‑to‑date zoneinfo; avoid homegrown date math.
    • Distinguish exact timestamps (store in UTC) from recurring/local events (store in local civil time).