4.2 kiloyear event
E89401
The 4.2 kiloyear event was a major global climatic downturn around 2200 BCE, marked by widespread aridification and cooling that is thought to have contributed to the collapse or transformation of several ancient civilizations.
All labels observed (2)
| Label | Occurrences |
|---|---|
| 4.2 kiloyear event canonical | 4 |
| 4.2 kyr event | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T742185 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: 4.2 kiloyear event Context triple: [Holocene, containsEvent, 4.2 kiloyear event]
-
A.
8.2 kiloyear event
The 8.2 kiloyear event was a sudden, short-lived global cooling episode during the early Holocene, likely triggered by massive meltwater outbursts disrupting North Atlantic ocean circulation.
-
B.
Holocene climatic optimum
The Holocene climatic optimum was a warm period roughly 9,000–5,000 years ago when global temperatures, especially in the Northern Hemisphere, were higher than today, influencing the spread of forests and early human civilizations.
-
C.
Cretaceous–Paleogene boundary
The Cretaceous–Paleogene boundary marks the geological transition 66 million years ago associated with a mass extinction event that wiped out non-avian dinosaurs and many other species, likely triggered by a large asteroid impact.
-
D.
Holocene
The Holocene is the current geological epoch, beginning around 11,700 years ago, characterized by relatively stable climate conditions and the development of human civilizations.
-
E.
Eocene–Oligocene climate transition
The Eocene–Oligocene climate transition was a major global cooling event around 34 million years ago that marked the shift from a greenhouse to an icehouse Earth, including the formation of large Antarctic ice sheets.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: 4.2 kiloyear event Target entity description: The 4.2 kiloyear event was a major global climatic downturn around 2200 BCE, marked by widespread aridification and cooling that is thought to have contributed to the collapse or transformation of several ancient civilizations.
-
A.
8.2 kiloyear event
The 8.2 kiloyear event was a sudden, short-lived global cooling episode during the early Holocene, likely triggered by massive meltwater outbursts disrupting North Atlantic ocean circulation.
-
B.
Holocene climatic optimum
The Holocene climatic optimum was a warm period roughly 9,000–5,000 years ago when global temperatures, especially in the Northern Hemisphere, were higher than today, influencing the spread of forests and early human civilizations.
-
C.
Cretaceous–Paleogene boundary
The Cretaceous–Paleogene boundary marks the geological transition 66 million years ago associated with a mass extinction event that wiped out non-avian dinosaurs and many other species, likely triggered by a large asteroid impact.
-
D.
Holocene
The Holocene is the current geological epoch, beginning around 11,700 years ago, characterized by relatively stable climate conditions and the development of human civilizations.
-
E.
Eocene–Oligocene climate transition
The Eocene–Oligocene climate transition was a major global cooling event around 34 million years ago that marked the shift from a greenhouse to an icehouse Earth, including the formation of large Antarctic ice sheets.
- F. None of above. chosen
Statements (53)
| Predicate | Object |
|---|---|
| instanceOf |
Holocene climatic anomaly
ⓘ
climatic event ⓘ |
| affects |
East Asia
ⓘ
Eastern Mediterranean ⓘ Middle East ⓘ
surface form:
Near East
North Africa ⓘ North Atlantic area ⓘ
surface form:
North Atlantic region
South Asia ⓘ |
| alsoKnownAs |
4.2 ka BP event
ⓘ
4.2 ka event ⓘ 4.2 kiloyear event ⓘ
surface form:
4.2 kyr event
|
| associatedWith |
collapse of the Akkadian Empire
ⓘ
collapse of the Indus Valley Civilization ⓘ crop failures ⓘ decline of the Old Kingdom of Egypt ⓘ famine ⓘ societal stress and migration ⓘ transformations in Early Bronze Age societies in the Levant ⓘ urban abandonment in some regions ⓘ widespread drought ⓘ |
| characterizedBy |
aridification
ⓘ
cooling ⓘ increased climate variability ⓘ |
| chronologyMethod |
layer counting in ice cores
ⓘ
radiocarbon dating ⓘ |
| classifiedAs | global-scale climatic perturbation ⓘ |
| duration | several centuries ⓘ |
| endTime | circa 1900 BCE ⓘ |
| hasCause |
changes in atmospheric circulation
ⓘ
shifts in monsoon systems ⓘ |
| hasEvidence |
archaeological data
ⓘ
ice core records ⓘ lake sediment records ⓘ marine sediment cores ⓘ pollen records ⓘ speleothem records ⓘ |
| impactOn |
Indus Valley
ⓘ
surface form:
Indus Valley urban centers
ancient Egyptian civilization ⓘ ancient Mesopotamian civilizations ⓘ pastoral and agricultural systems ⓘ |
| partOf | Holocene ⓘ |
| recognizedBy |
archaeologists
ⓘ
geologists ⓘ paleoclimatologists ⓘ |
| relatedTo |
8.2 kiloyear event
ⓘ
Holocene climatic optimum ⓘ Little Ice Age ⓘ |
| significance | considered one of the most severe Holocene climate events ⓘ |
| startTime | circa 2200 BCE ⓘ |
| timePeriod |
approximately 4.2 thousand years before present
ⓘ
around 2200 BCE ⓘ |
| uncertainty | spatial extent and exact mechanisms are debated ⓘ |
| usedIn | studies of climate–society interactions ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: 4.2 kiloyear event Description of subject: The 4.2 kiloyear event was a major global climatic downturn around 2200 BCE, marked by widespread aridification and cooling that is thought to have contributed to the collapse or transformation of several ancient civilizations.
Referenced by (5)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
4.2 kyr event