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Abstract Proxy‐based reconstructions of long‐term Atlantic tropical cyclone (TC) variability reveal low‐frequency oscillations in regional TC landfalls over the Common Era. However, the limited spatial coverage and increased uncertainty of the proxy records complicates assessments of this feature. Here we present a new multi‐ensemble set of synthetic TCs downscaled from the Last Millennium Reanalysis project, which is based on sea surface temperatures that more accurately reflect past conditions. Throughout ensemble members, there are coherent multi‐centennial shifts in landfalls with persistent intervals of increased (decreased) occurrence along the eastern US concurrent with inverse activity in the southwest Caribbean and Gulf of Mexico, associated with basin‐scale redistributions of storm tracks. The emergent TC‐dipole from modeled climate provides context and support for its presence within proxy‐reconstructions. Furthermore, dipole recurrence across ensembles demonstrates that it arises from sea surface temperature‐informed climate processes. However, timing differences between ensembles indicate that transient atmospheric variability influences dipole position. 

Abstract The short and biased observational record of tropical cyclones (TCs) limits scientific understanding of how these destructive storms respond to climate forcing. Paleohurricane records use natural archives (tree rings, coarse‐grained sediment) to reconstruct TC properties (frequency and intensity of rainfall, wind) over the past few hundreds to thousands of years. However, different sensitivities and sampling biases in the various paleohurricane proxies restrict our ability to compile these records into regional or basin‐scale TC estimates. Here we test how well pseudo tree‐ring records of paleohurricanes capture TC rainfall and occurrence. Using a large set of statistically downscaled storms forced with the Max Planck Institute (MPI‐ESM‐P) model as boundary conditions for the past millennium, we generate a 1000‐member ensemble of pseudo tree‐ring records of latewood width from southern Mississippi using a Poisson process‐based random draw. Pseudo records convert synthetic TC rainfall into latewood width using a previously published statistical calibration and seasonal sensitivity. We show that fourth quantile thresholds applied to pseudo latewood data successfully identify years with TC strikes. Comparing pseudo tree‐ring records with pseudo sediment records from the Gulf Coast indicates promise in combining proxies sensitive to TC rainfall with proxies sensitive to storm overwash. Sediment records that are sensitive to lower intensity storms (≥Saffir Simpson Category 1) are more compatible with tree‐ring records, suggesting a need for more of these low intensity threshold records in the Gulf to facilitate future multi‐proxy efforts to reconstruct past TC properties.