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Sediment cores from blue holes have emerged as a promising tool for extending the record of long‐term tropical cyclone (TC) activity. However, interpreting this archive is challenging because storm surge depends on many parameters including TC intensity, track, and size. In this study, we use climatological‐hydrodynamic modeling to interpret paleohurricane sediment records between 1851 and 2016 and assess the storm surge risk for Long Island in The Bahamas. As the historical TC data from 1988 to 2016 is too limited to estimate the surge risk for this area, we use historical event attribution in paleorecords paired with synthetic storm modeling to estimate TC parameters that are often lacking in earlier historical records (i.e., the radius of maximum wind for storms before 1988). We then reconstruct storm surges at the sediment site for a longer time period of 1851–2016 (the extent of hurricane Best Track records). The reconstructed surges are used to verify and bias‐correct the climatological‐hydrodynamic modeling results. The analysis reveals a significant risk for Long Island in The Bahamas, with an estimated 500‐year stormtide of around 1.63 ± 0.26 m, slightly exceeding the largest recorded level at site between 1988 and 2015. Finally, we apply the bias‐corrected climatological‐hydrodynamic modeling to quantify the surge risk under two carbon emission scenarios. Due to sea level rise and TC climatology change, the 500‐year stormtide would become 2.69 ± 0.50 and 3.29 ± 0.82 m for SSP2‐4.5 and SSP5‐8.5, respectively by the end of the 21st century. Plain Language Summary: Paleohurricane sediment records can capture tropical cyclone (TC) landfall and associated storm surge severity over several millennia, providing an extended record to quantify long‐term storm surge risk. Interpretation of these records is difficult because storm surge depends on many parameters such as TC intensity, track, and size. In this study, we use hydrodynamic modeling to identify which historical TCs between 1851 and 2016 transported sediment into underwater sinkholes near Long Island in The Bahamas. Supplementing the historical record with synthetic TCs created by a computer model, we leverage our interpretation of the paleorecord to approximate the size and surge level for storms prior to 1988 for which observations are unavailable. Next, we integrate the reconstructed storm surge levels and climatological‐hydrodynamic modeling to estimate long‐term storm surge hazards for the area. Finally, we apply the integrated model to assess storm surge risk for Long Island under future climates (SSP2‐4.5 and SSP5‐8.5) and sea level rise and find a significant increase in TC hazard risk for this location by the end of the century. Key Points: Hydrodynamic modeling is used to identify event beds in paleorecordsStorm sizes and surges at the sediment site are reconstructed for 1850–2016 to bias‐correct climatological‐hydrodynamic modeling resultsThe surge risk under two carbon emission scenarios (SSP2‐4.5, SSP5‐8.5) and sea level rise is quantified for Long Island, Bahamas [ABSTRACT FROM AUTHOR]

Hurricane Dorian (2019), a category-5 tropical cyclone (TC), was characterized by a large spread in track forecasts as it moved northwest. A set of 80 ensemble forecasts from the Hurricane Analysis and Forecast System (HAFS) was produced to evaluate Dorian's track spread and the factors that contributed to it. Track spread was particularly critical at long lead times (5–7 days after initialization near the Lesser Antilles), because of the uncertainty in the location of landfall and hazards. Four clusters of members were analyzed based on the 7-day track, characterized by Dorian moving: 1) slowly near the northern Bahamas (closest to reality), 2) across the Florida Peninsula, 3) slowly into Florida's east coast, and 4) quickly north of the Bahamas. Ensemble sensitivity techniques were applied to identify areas that were most critical for Dorian's track. Key differences were found in the strength of the subtropical ridge over the western Atlantic Ocean with a weaker ridge and slower easterly steering flow in the offshore groups. Subtle differences in the synoptic pattern over the United States also appeared to affect the timing of Dorian's northward turn, specifically the strength of a shortwave trough moving over the Ohio Valley. Despite some early track differences, the correlation between early and late track errors was not significant. An examination of four members further highlights the differences in steering and the strength of the subtropical ridge. This study demonstrates the utility of ensemble datasets for studying TC forecast uncertainty and the importance of medium-range modeling of synoptic-scale steering features to accurately predict the track of tropical cyclones. Significance Statement: Hurricane Dorian was a catastrophic hurricane for the Bahamas and got very close to Florida without directly impacting the state. Some early forecasts showed the storm moving directly into or across Florida; others correctly showed the storm stalling over the Bahamas and then turning northward. This track forecast uncertainty made preparations in Florida challenging; therefore, we wanted to better understand why Dorian took the track that it did, to see what this tells us about the factors that affect hurricane tracks, and learn for future storms. We looked at an ensemble of 80 runs of a hurricane model, initiated at the same time. Some runs showed a Florida landfall; others showed Dorian stalling over the Bahamas. The strength of the subtropical ridge over the Atlantic north of Dorian and an upper-level trough of low pressure over the United States were key influences on storm path. These two large-scale features were better forecast in the ensemble members that correctly showed Dorian stalling and turning northward. This study shows how useful ensembles can be for understanding the processes driving hurricane motion and also shows that it is critical to forecast multiple synoptic-scale features correctly to accurately predict a hurricane's track 5–7 days in advance. [ABSTRACT FROM AUTHOR]

The article discusses speculation regarding where explorer Christopher Columbus first made landfall in the Americas. The author notes that while San Salvador, also known as Cat Island, had been accepted as the probable location of Columbus' landfall, historian Martin de Navarrete suggested Columbus may have landed on Turk Island. British naval captain A.B. Becher asserted that Columbus has landed on Watling Island, a suggestion supported by historians Justin Winsor and Rudolph Cronau. An excerpt from a journal written by Columbus regarding his landfall and the sighting of lights on one of the islands is presented. The author notes changes to Spanish maps of the Bahamas.