High-resolution paleo-storm reconstructions from Eastern Canada align with late Holocene northwestern Atlantic hurricane records

Abstract

Atlantic Canada experiences frequent major storms, particularly tropical cyclones transitioning into post-tropical storms. Events such as Hurricane Fiona (2022), Dorian (2019), and Juan (2003) have caused significant damage, loss of life, and coastal erosion, exacerbated by sea level rise and warming waters. Despite this, centennial- to millennial-scale storm records in the region remain scarce. Existing studies in North America focus primarily on marine and coastal overwash records, with limited use of aeolian mineral inputs in ombrotrophic peatlands as storm proxies. Here, we address these gaps by analysing grain-size and geochemical data from two peatlands in Quebec, Canada’s Magdalen Islands. Our 4000-year peat-based storm reconstructions reveal consistent storm signals with three key intervals of increased activity: 800–550 BCE, 500–750 CE, and 1300–1700 CE. These records align with marine overwash archives from eastern Canada, the US, and the Bahamas, supporting reduced storminess during the Medieval Climate Anomaly and heightened activity during the Little Ice Age. This regional coherence suggests storm variability at higher latitudes is strongly influenced by local climatic drivers, such as sea surface temperature gradients and storm intensification mechanisms, rather than tropical cyclone formation alone. Despite broad similarities, notable discrepancies in geochemical and mineralogical profiles between our two peatlands highlight the influence of site-specific factors, including proximity to sediment sources, bog size, and local geomorphology, on sediment deposition and storm signal strength. These findings underscore the importance of site selection and local context when interpreting peat-based storm records. Furthermore, challenges remain in calibrating peat proxies to historical storm events, limiting direct event attribution over the past 150 years. Our study demonstrates the complementary value of peatland archives alongside marine overwash records in reconstructing paleo-storm activity, enriching understanding of storm dynamics and expanding potential reconstruction sites, particularly in mid-latitude coastal regions. Continued research is needed to refine calibration methods and clarify climatic mechanisms driving storm variability, which is essential for projecting future storm impacts in Atlantic Canada.