The effect of weather conditions on burnt bone fragmentation.

This research assesses how weather conditions, such as temperature and rainfall, affect the fragmentation of burnt bone. The recovery of human remains from fatal fire scenes is often hampered by the fragmentary nature of the material, and through understanding how weather factors affect this fragmentation, it may be possible to adjust recovery timelines and protocols to maximise the quantity and quality of condition of the material recovered. These data are also valuable as a baseline for expected fragmentation, and expected differences in fragmentation, under different weather conditions. Sus scrofa (domestic pig) limbs were burned in a series of wood fires spaced over a period of eight months, from winter through fall, in a warm summer continental climate (Köppen-Geiger classification Dfb). Bone fragments were sorted by size and the proportional weights of each size category were compared to isolate any differences in fragmentation. Results suggest that in freezing conditions with remains recovery occurring the day after the fire, increased fragmentation is observed in younger remains but not in older remains. In older remains fragmentation is highest when temperatures fluctuate around 0 °C. It was observed that when remains recovery is delayed, fluctuating temperatures have a larger impact on fragmentation in the short term and freezing conditions are more significant in the longer term. Wet weather conditions increase levels of fragmentation.