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Historical Records

The richest trove of maritime weather information is waiting to be explored


In climate research, long datasets are invaluable. They help scientists to establish a baseline of weather and climate variability, against which to measure changes over time, feed into models for sophisticated reanalysis efforts going back to the 1800s, and illuminate interactions between different components of the climate system. Unfortunately, pre-19th century instrumental data from regions beyond Europe and North America is sparse. A growing field of scholarship addresses this gap by interpreting historical records. Historic documentation (e.g., navy, merchant, and whaling ship logbooks, colonial port records) contain untapped potential for daily, quantifiable maritime weather information. Recording atmospheric conditions in the nautical context was essential to safe travel. One of the richest troves of maritime weather information is contained in the vast archives of ships’ logs, in which officers routinely recorded weather information during their voyages.

New England whaling ship logbooks

This project taps an as-yet unexamined trove of climate data: U.S. whaling ship logbooks for voyages around the world starting in the late 1700s. The records whalers generated predate most extant instrumental climate data. 18th to 19th-century ships’ logbooks and related maritime documentation contain systematic weather observations, including estimates of wind strength and direction, sea state, precipitation, and notable storm events over several centuries; notable changes in weather were also recorded each day. Although pre-instrument maritime weather measurements were not recorded in a quantitative numerical format, they were nevertheless highly systematic, and conformed to a rigorous, standardized classification scheme commonly used by professional mariners across the English-speaking world.

New Bedford Whaling Museum~2,500
New Bedford Free Public Library500
Providence Public Library~800
Nantucket Historical Association~400
Mystic Seaport (Blunt White Library)250

This logbook-derived data can lead to a better understanding of modern climate records and help predict future changes.”

Timothy Walker, University of Massachusetts, Dartmouth, left with co-investigator, Caroline Ummenhofer, Woods Hole Oceanographic Institution, right.


Walker TD, and Ummenhofer CC. (2024). Extracting global maritime weather data from New England whaling and Portuguese Navy logbooks (1740-1960). Mainsheet, 1, 108-123, doi:10.61355/001c.94790. Reprint

Ummenhofer CC. (2019). Mining historical and environmental archives for climate information. Poster at 9th Bonn Humboldt Award Winners’ Forum “Frontiers in Biogeography, Ecology, Anthropology, and Evolution. Humboldt and the ‘Cosmos’ revisited in the 21st Century”, Oct. 16-20, 2019, Bonn, Germany.

Ummenhofer CC and Walker TD (2021). Mining five centuries of climate and maritime weather data from historic records. NAS Ocean shot contributions for U.S. Launch of U.N. Decade of Oceans, Feb. 2021.

Walker TD (2019). Team up to study climate change. Historic Nantucket, 69 (2), 31.

Walker TD and Ummenhofer CC. (2019). Assessing historic changes in climate in the Indian Ocean using American whaling logbooks and other New England maritime archival sources (circa 1785-1910). Biennial Whaling History Symposium, Apr 27-28, 2019, New Bedford, MA, USA.

Ummenhofer CC, Münch B, Meeker E, Johnson V, and Walker TD. (2022). Historic changes in Southern Hemisphere wind patterns since the late 1700s from reanalyses and American whaling ship logbooks. Oral presentation for 13th ICSHMO Conference, Feb. 8-12, 2022, Christchurch, NZ.

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