Last Millennium Hurricane Activity linked to Endogenous Climate Variability

Abstract

Although Atlantic hurricane risk is expected to increase in a warming climate, projecting trends in hurricane frequency over the present century is still highly uncertain. The short instrumental record limits our understanding of hurricane activity and its relationship to climate, especially on multi-decadal and longer time scales. Here we extend the instrumental hurricane frequency record using two independent sources of information: (1) a reconstruction of basin-wide Atlantic hurricane frequency over the last millennium, developed from sedimentary paleohurricane records; (2) a statistical model of hurricane activity using sea surface temperatures (SSTs) from the Last Millennium Reanalysis (LMR) datasets. We find statistically significant agreement between the two estimates, suggesting that a robust climate signal of hurricane frequency over the past millennium can be captured from proxy data. Neither estimate of hurricane frequency indicates that the late 20th century hurricane frequency is outside the range seen over the past millennium. Numerical simulations using a hurricane-permitting climate model suggest that hurricane activity over the last millennium was likely driven by endogenous climate variability and linked to anomalously warm SSTs over the Atlantic Main Development Region (MDR) as well as cold phases of Interdecadal Pacific Oscillation (IPO) SSTs. The forced signal estimated from the Last Millennium Ensemble (LME) project suggests that volcanic eruptions can induce peaks in hurricane activity, but such peaks would likely be too weak to be detected from reconstruction records due to large endogenous variability.

Northeastern Caribbean Rainfall Variability Linked to Solar and Volcanic Forcing

“…Moreover, sedimentary archives do not necessarily record high precipitation events, and tropical cyclones and depressions with comparably weak wind speeds or storm surges can still bring a considerable amount of δ 18 O depleted rainfall (e.g., Govender et al., 2013; Warken, Kuchalski, et al., 2022). Interestingly, our record shares a similar pattern with a recent study combining sedimentary paleo‐hurricane records and a statistical reconstruction of hurricane activity dependent on SSTs (Yang et al., 2024) (Figure 3). Taking dating uncertainties into account, periods of lower speleothem δ 18 O values appear to coincide with times of higher statistical probability of hurricane occurrence associated with warmer SSTs (Yang et al., 2024).…”

“…Interestingly, our record shares a similar pattern with a recent study combining sedimentary paleo‐hurricane records and a statistical reconstruction of hurricane activity dependent on SSTs (Yang et al., 2024) (Figure 3). Taking dating uncertainties into account, periods of lower speleothem δ 18 O values appear to coincide with times of higher statistical probability of hurricane occurrence associated with warmer SSTs (Yang et al., 2024). We interpret this common pattern such that warmer SSTs generally support enhanced convection and cyclogenesis, from tropical waves, depressions, tropical storms, and hurricanes, which altogether result in higher rainfall amounts affecting Puerto Rico.…”

“… Comparison of several tropical cyclone (TC) reconstructions. From top to bottom: (a) Atlantic hurricane activity index reconstruction (Burn & Palmer, 2015); (b) tropical Atlantic hurricane activity reconstruction (Yang et al., 2024); (c) PR‐LA‐C2 δ 18 O record (this study); (d) Puerto Rican hurricane activity reconstructed from coral luminescence records from Puerto Rico (Nyberg et al., 2007); (e) historical counts of hurricane/tropical cyclones per 5 years in Puerto Rico as archived in the HURDAT2 database (Landsea & Franklin, 2013). Blue bars indicate times of low speleothem δ 18 O values indicative of enhanced convective activity and higher rainfall amounts.…”

“…In this respect, evidence of a dominant influence of natural forcing, that is, solar activity and energetic volcanic eruptions, on Caribbean multidecadal to centennial SSTs and hydroclimate changes has been found by a number of studies (Black et al., 1999; Burn & Palmer, 2014; Haase‐Schramm et al., 2003; Hodell et al., 2001; Pollock et al., 2016; Ridley et al., 2015; Smirnov et al., 2017; Waite et al., 2020; Warken et al., 2021; Winter et al., 2015; Yang et al., 2024). For example, a reconstruction of Mesoamerican precipitation based on a speleothem record from the Yucatán Peninsula revealed a strong association between the occurrence of multidecadal drying phases during the past three centuries and clusters of strong tropical volcanic eruptions (Winter et al., 2015).…”

“…The spatial and temporal distribution of rainfall in Central America and the Caribbean is mainly controlled by the Inter‐Tropical Convergence Zone (ITCZ) and the North Atlantic Subtropical High (NASH), which are responsible for the characteristic seasonal cycle with enhanced convection, cyclogenesis, and associated rainfall amounts in the warm summer season (Martinez et al., 2019). In addition, their long‐term variability affects rainfall patterns and tropical cyclone (TC) activity on decadal to centennial timescales (Hernández Ayala, 2019; Pausata & Camargo, 2019; Taylor et al., 2002; Yang et al., 2024).…”