daylight saving time
Let an agent explain daylight saving time, relay history, rules by region, effects and abolition debates from time standards, government and research sources with positions attributed, describe the named zones and regional practices, and distinguish DST from standard time, time zones, UTC offsets in general and permanent daylight time proposals.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent explain daylight saving time, relay history, rules by region, effects and abolition debates from time standards, government and research sources with positions attributed, describe the named zones and regional practices, and distinguish DST from standard time, time zones, UTC offsets in general and permanent daylight time proposals.
The practice of advancing clocks, usually by one hour, during the warmer months so that evenings have more daylight, called summer time in Europe, where the EU synchronises changes on the last Sundays of March and October, and daylight saving time in North America, as with Eastern Daylight Time; first adopted widely by Germany and Austria-Hungary in 1916, it is used in many but not all countries, with Italy and others following EU rules, and debates about abolishing clock changes, including a 2019 European Parliament vote not implemented by member states and US proposals for permanent daylight time, are attributed, citing effects on health, energy and safety.
What it is for: Shifting clock time to use evening daylight.
It can be explain history and rules; relay regional practices; describe named zones; present abolition debates with attribution.
Distinguishing features
Seasonal change
One-hour shift typical
Regional variation
Contested benefits
What it looks like
Not a physical object; seen in clock changes and time zone abbreviations.
Physical character
first national adoption: 1916 year - Germany and Austria-Hungary
EU summer time rules: last Sunday of March to last Sunday of October note - Directive 2000/84/EC
European Parliament vote to end changes: 2019 year - not implemented, check current status
How it is recognised
Seasonal clock advance
Eastern Daylight Time, summer time in Europe, daylight saving time in Italy
Standard time is the base; time zones are regions; UTC offsets define local time; permanent daylight time would end changes
Related models
is a kind of - in registry terms
is regulated by - in the EU
includes -
is contrasted with -
In practice
Families and kinds
European summer time
North American daylight time
southern hemisphere DST
double summer time historically
Standards and regulation
EU Directive 2000/84/EC
US Energy Policy Act of 2005 DST dates
IANA time zone database
Failure modes and hazards
Stale rules and dates
Partisan framing of abolition debates
Scheduling errors across zones
Also called
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Understand What daylight saving time is.
Attribution.
Definition
Definition.
Definition
Definition.
- What is daylight saving time, and how does it differ from standard time, time zones, UTC offsets and permanent daylight time? definition
- Is the question about current clock change dates, which need current sources, history or health debates? boundary
Zones
Named zones.
Zones
Zones.
- What are Eastern Daylight Time, European summer time and Italy s practice? definition
- Which entry fits the specific zone? action
History History.
Sources.
Origins
Origins.
Origins
Origins.
- How did Willett s proposal and the 1916 wartime adoption start DST? provenance
- Which references are standard? provenance
Rules
Current rules.
Rules
Rules.
- What are current DST rules in the EU and US, checked against current sources? provenance
- Which sources are cited? provenance
Effects Effects and debates.
Attribution.
Health
Health effects.
Health
Health.
- What do sleep researchers and medical bodies say about clock changes and health, with positions attributed? provenance
- Is the presentation neutral and attributed? boundary
Energy
Energy savings.
Energy
Energy.
- What do studies find about energy savings from DST, with findings attributed? provenance
- Which entry fits daylight saving time energy studies? action
Context Policy.
Regulation.
EU
EU abolition proposal.
EU
EU.
- What happened to the EU proposal to end clock changes, checked against current sources? provenance
- Is the information current? boundary
Time zone data
IANA database.
Time zone data
Time zone data.
- How does the IANA time zone database track DST changes for software? provenance
- Which entry fits tz database? action
What the second pass must settle
- How should the status of EU and US abolition proposals be kept current?
- Should national DST histories be separate entries?
- How should the IANA database be linked?