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OIPC (Online Isotopes in Precipitation Calculator)

Definition

A web-based tool and database compiling the IAEA GNIP station network data and providing interpolated δ18O and δ2H predictions for any geographic coordinate. One of the main reference resources for forensic isoscape queries.

Data source
IAEA GNIP station network
Outputs
Interpolated δ18O and δ2H predictions by coordinate
Access
Web-based tool

Common questions

How is OIPC used in a forensic geographic origin case?+

An examiner compares isotope ratios measured in hair, bone, or teeth against OIPC's predicted precipitation values for candidate regions to narrow down where a person likely lived or traveled before death.

What limits the precision of OIPC-based conclusions?+

Predictions are interpolated between sparse monitoring stations and reflect precipitation, not tissue, isotope values directly, so results narrow a probable region rather than pinpoint a single location.

Related terms

δ18O (Delta-18-O)
The ratio of oxygen-18 to oxygen-16 in a sample expressed in per-mil deviation from the Vienna Standard Mean Ocean Water (VSMOW) standard....
δ2H (Delta Deuterium)
The ratio of deuterium to hydrogen in a sample expressed in per-mil deviation from VSMOW. Covaries with δ18O along the global meteoric...
Global Meteoric Water Line (GMWL)
The linear relationship δ2H = 8 × δ18O + 10 that describes the global co-variation of O and H isotopes in precipitation....
Isoscape
A map of isotope ratio variation across a geographic area, derived from systematic sampling of soil, water, plant, or mineral material; used...
Tissue-Specific Incorporation
The principle that different tissues record isotope signals over different time windows: enamel permanently records childhood; hair records month-by-month recent history; bone...

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