Quirks & Quarks

Priests and traders collected climate data 600 years ago

Historical records - kept for religious and economic reasons - of the critical dates of freezing and thawing of lakes and rivers, help climate scientists today.

Unique climate records record freezing and thawing in history

(Terhi Korhonen)
Precise collection of data about temperatures and changing climate is mostly a modern practice, as climate scientists seek to better understand the impact of greenhouse gases on global temperature and climate patterns. But the recent discovery of accurate recording of important climate phenomenon, stretching back six centuries is providing a unique and valuable perspective on recent climate change.

Dr. Sapna Sharma, a biologist from York University, and her colleagues, have analysed records kept since the late 15th century by Japanese priests, recording the date on which a particular lake froze; and a second set of records, kept by traders since the 17th century, noting the time ice broke up on a river in Finland.

They found accurate parallels with "proxy" records from tree rings and lake sediments that further confirm Industrial Age climate warming, and recent climate instability.

Related Links

Paper in Nature Scientific Reports
- York University release
- CBC News story
Smithsonian Magazine story
National Geographic story
- Dr. Sharma previously on Quirks