New England whaling ship logbooks and reanalyses reveal shifts in global wind patterns since the late 1700s

Abstract

Maritime weather data contained in U.S. whaling ship logbooks are used to assess historical changes in global wind patterns. We focus on unexploited caches of archival documentation, namely U.S. whaling logbooks of voyages spanning the period 1790 to 1910 from New England archives housed by the New Bedford Whaling Museum, Nantucket Historical Association, and Providence Public Library. The logbooks, often covering multi-year voyages around the globe, contain systematic weather observations (e.g., wind strength/direction, sea state, precipitation) at daily to sub-daily temporal resolution. The qualitative, descriptive wind recordings of wind strength and direction by the whalers are quantified and compared with reanalysis products where applicable. Following extensive quality control, we find overall good agreement in wind strength and direction for the whaling logbook wind records with reanalysis products for mean and seasonal climatologies. Variations in wind fields associated with modes of variability, such as the North Atlantic Oscillation or El Niño-Southern Oscillation, are also captured by the whaling ship recordings for North Atlantic and Pacific surface wind patterns. The quantified wind recordings are also employed to help address contemporary questions in climate science, such as long-term shifts in position and strength of the Southern Hemisphere westerlies since the late 1700s, strengthening of the Pacific equatorial trade winds since the 19th century, as well as changes in South Asian monsoon characteristics. Our results demonstrate that the historical records provide an important long-term context for changing maritime wind patterns in remote ocean regions lacking observational records during the 19th century.