Clue from nature AD 1517

The year before the 1518 dancing plague: a severe spring drought

Two independent witnesses. Tree rings (Old World Drought Atlas) near Strasbourg: summer soil moisture in 1517 is the 4th lowest of 901 years (1000 to 1900), z = -2.69. Written records (Glaser and Kahle's monthly index for Germany): March to June 1517 is tied for the 3rd driest spring in 400 years (1500 to 1900), behind only 1540, the great megadrought, and 1893; June 1516 to June 1517 is the 12th driest 13 months. The summer of 1516 was dry too. July and August 1517 then turned wet. June 1517, when rye flowers and ergot infects it, was dry. Note on the tree-ring number: the drought atlas measures summer soil moisture, which carries over from earlier months (soil memory), so its very low 1517 value reflects the dry 1516 and the dry spring of 1517 more than the wet July and August.

How it connects

This clue from nature supports this hunch Strasbourg 1518 came after a great drought and two years of dear bread two independent records show a severe drought in 1516 to 1517

This clue from nature argues against The dancing plagues were ergot poisoning June 1517 was dry: bad for ergot

This clue from nature is a clue for What caused the dancing plagues (1374, 1518 and others)?

This clue from nature we read it in Glaser and Kahle 2020, Reconstructions of droughts in Germany since 1500, Climate of the Past 16, 1207; monthly precipitation and temperature indices from written records, tambora.org

This clue from nature we read it in Cook et al. 2015, Old World Drought Atlas: tree-ring summer scPDSI on a 0.5 degree grid, AD 0 to 2012, NOAA study 19419

This clue from nature came from this step Tested the dancing plagues against ergot weather