Microclimate
Definition
The localised temperature and humidity conditions immediately at the body surface, which often differ from the nearest weather-station record by several degrees. Using ambient station data without a microclimate correction is one of the most common sources of PMI error.
- Scope
- Temperature and humidity at the body surface
- Typical deviation
- Several degrees from the nearest weather station
- Relevance
- Accurate PMI and ADD estimation
- Common error
- Using raw station data uncorrected
Common questions
What causes the gap between station data and body-site conditions?+
Shade, indoor enclosure, vehicle interiors, clothing, and burial all buffer or amplify temperature relative to an open weather station, so the air actually touching the body rarely matches the regional record exactly.
How do entomologists correct for this in practice?+
They deploy a data logger at the actual scene for a period after discovery and compare it against the nearest station's simultaneous readings to derive a site-specific correction, which is then applied retrospectively to the historical station record.
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