A decadally-resolved paleohurricane record archived in the late Holocene sediments of a Florida sinkhole

Abstract

A 4500-year record of hurricane-induced storm surges is developed from sediment cores collected from a coastal sinkhole near Apalachee Bay, Florida. Recent deposition of sand layers in the upper sediments of the pond was found to be contemporaneous with significant, historic storm surges at the site modeled using SLOSH and the Best Track, post-1851 A.D. dataset. Using the historic portion of the record for calibration, paleohurricane deposits were identified by sand content and dated using radiocarbon-based age models. Marine-indicative foraminifera, some originating at least 5 km offshore, were present in several modern and ancient storm deposits. The presence and long-term preservation of offshore foraminifera suggest that this site and others like it may yield promising microfossil-based paleohurricane reconstructions in the future. Due to the sub-decadal (~ 7 year) resolution of the record and the site's high susceptibility to hurricane-generated storm surges, the average, local frequency of recorded events, approximately 3.9 storms per century, is greater than that of previously published paleohurricane records from the region. The high incidence of recorded events permitted a time series of local hurricane frequency during the last five millennia to be constructed. Variability in the frequency of the largest storm layers was found to be greater than what would likely occur by chance alone, with intervals of both anomalously high and low storm frequency identified. However, the rate at which smaller layers were deposited was relatively constant over the last five millennia. This may suggest that significant variability in hurricane frequency has occurred only in the highest magnitude events. The frequency of high magnitude events peaked near 6 storms per century between 2800 and 2300 years ago. High magnitude events were relatively rare with about 0-3 storms per century occurring between 1900 to 1600 years ago and between 400 to 150 years ago. A marked decline in the number of large storm deposits, which began around 600 years ago, has persisted through present with below average frequency over the last 150 years when compared to the preceding five millennia.

Shipwreck rates reveal Caribbean tropical cyclone response to past radiative forcing

“…3E). Reduced seventeenth-century CTC activity has also been recorded in an array of Caribbean and Gulf of Mexico lowerresolution TC proxies (10)(11)(12)(23)(24)(25) and is concurrent with increased ocean stratification-possibly linked to reduced TCinduced mixing-near Great Bahama Bank (26) and increased aridity in various proxy records from the circum-Caribbean region (27,28).…”

“…The Maunder Minimum (MM; 1645-1715 CE), the most severe change in solar irradiance in documented history (7,8), is of particular interest in this context, but TC proxy records that cover this period are scarce, often present a conservative estimate of the total number of storm events (9), and largely have insufficient time resolution to distinguish the MM (6,(10)(11)(12). Documentary data sets are the main source of paleotempestology information of appropriate temporal resolution, but most document-based TC studies have primarily focused on long-term TC climatology (e.g., seasonality, recurrence intervals) rather than interannual or decadal-scale variability (13,14).…”

Extreme flood event reconstruction spanning the last century in the El Bibane Lagoon (southeastern Tunisia): a multi-proxy approach

“…These fields of research were successfully applied in the western North Atlantic (Donnelly and Woodruff, 2007), northwestern Florida (Liu and Fearn, 2000;Lane et al, 2011;Das et al, 2013), the northeastern United States (Parris et al, 2010), the central Pacific (Toomey et al, 2013), southern Japan (Woodruff et al, 2009), western Australia (Nott, 2011), northeastern New Zealand (Page et al, 2010), northern Europe (Sorrel et al, 2012), or the western Mediterranean (Dezileau et al, 2011(Dezileau et al, , 2016Sabatier et al, 2012;Raji et al, 2015;Degeai et al, 2015). Such studies are still scarce in southern Tunisia, despite the importance of these topics in Mediterranean coastal areas.…”

Science Needs for Sea-Level Adaptation Planning: Comparisons among Three U.S. Atlantic Coastal Regions

“…Presentation topics on cross-disciplinary research included observational and geological reconstructions of former sea levels (e.g., Kemp et al 2011;Horton et al 2013), tropical cyclone climatologies and storm surge modeling (e.g., Mann et al 2009;Lane et al 2011), and semi-empirical models of global sea-level rise (e.g., Vermeer and Rahmstorf 2009). The afternoon had two components: (a) two to four presentations by invited local experts on planning issues in their regions (one additional science presentation was made in the afternoon of the North Carolina workshop); and (b) breakout groups that discussed key information needs for sea level and coastal inundation planning.…”