Hurricane Frequency Research Articles

Hurricanes threaten species and alter evolutionary trajectories on tropical islands

Hurricanes are natural phenomena, but anthropogenic climate change will cause hurricanes to be stronger and more frequent in the future. It has long been known that hurricanes impact plants and animals, but only recently has the impact on biodiversity been mapped globally, showing that species at risk of extinction due to hurricanes are largely restricted to tropical islands. Tropical islands harbor many plants and animals found nowhere else, many of which are currently threatened, and tropical islands have already suffered a disproportionate number of species extinctions due to human activity and introductions of non-native species. The big question is whether species on tropical islands are adapted to hurricane disturbance and will be able to cope with stronger and more frequent storms, or whether tropical islands will see a wave of hurricane-induced extinctions in the future. Here, we discuss this question and how hurricanes will reshuffle interactions between species - such as those between nectarivorous birds and their flowers - and will alter evolutionary trajectories for coadapted species. Moreover, we discuss the role of life history and other taxa-specific traits, such as diet preferences and dispersal ability, both to survive the direct and indirect impact of hurricanes and to recolonize islands when local populations have been eliminated. We also highlight how topographic complexity and island area may buffer against hurricanes; thus, biodiversity on small and low-lying islands should be more impacted than biodiversity on large and mountainous islands. We end by discussing conservation efforts to diminish the detrimental ecological and evolutionary effects of stronger and more frequent hurricanes on tropical islands.

MODERN TRENDS IN GLOBAL ENERGY IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT AND DECARBONIZATION

The article presents data from authoritative international organizations on the noticeable change in the planet's climate compared to the pre-industrial period. It is emphasized that in recent years, climate change has become especially intense. One of the results of climate change is the increase in the frequency and destructive effects of hurricanes in various parts of the planet, droughts and crop losses in agriculture, floods, and rising sea levels, which leads to large economic losses. An important area of decarbonization of the global economy is the production of electricity using climate-neutral energy sources. The article provides a comprehensive comparative analysis of the efficiency of traditional large nuclear reactors and small modular reactors (SMRs). Significant technological, environmental and economic advantages of SMRs are noted. A comprehensive model for the development of global energy in the context of decarbonization is proposed, which includes innovative areas: SMRs, large nuclear power plants, wind, solar energy and the use of biofuels.

A temperature tipping point in hypoxic zone size

AbstractTemperature increases will have ubiquitous effects on aquatic food webs, from microbes to consumers, and affect the quality and quantity of carbon flows within and between water layers. A decline in the biological pump moving carbon from surface to lower layers is anticipated. We reviewed 37 years of data on hypoxic zone size and water quality in the northern Gulf of Mexico to determine if air and bottom water temperature increases (0.5°C decade−1) are significantly related to variations in its areal size. There was no significant decline in important river water quality in the 24 years since the national Hypoxia Action Plan was developed to reduce its size. Changes in the ratio of km2 hypoxia per 1000 mt nitrate loading from the Mississippi River from 2000 to 2023 reveals a tipping point in the hypoxic zone size that is driven by ocean warming. Biological factors varying with temperature such as ectotherm growth rates, zooplankton grazing, cell sinking rates, and diatom sequestration of Si or N are apparently more important influences on recent hypoxic zone size than variations in physical factors. This tipping point may be common to similarly warmed and eutrophic coastal waters where warming will likely result in diminished oxygen deficiency (< 2 mgO2 L−1). Hypoxia and food web models assuming a stationary equipoise of nutrient loadings, ratios and food webs will be deficient as coastal waters warm further, coastal storm and hurricane frequency increase and land uses in the watershed are altered with climate change.

Modeling the Effects of Increased Hurricane Frequency on the Tropical Forest Carbon Cycle

Models project that climate change is increasing the frequency of severe storm events such as hurricanes. Hurricanes are an important driver of ecosystem structure and function in tropical coastal and island regions and thus impact tropical forest carbon (C) cycling. We used the DayCent model to explore the effects of increased hurricane frequency on humid tropical forest C stocks and fluxes at decadal and centennial timescales. The model was parameterized with empirical data from the Luquillo Experimental Forest (LEF), Puerto Rico. The DayCent model replicated the well-documented cyclical pattern of forest biomass fluctuations in hurricane-impacted forests such as the LEF. At the historical hurricane frequency (60 years), the dynamic steady state mean forest biomass was 80.9 ± 0.8 Mg C/ha during the 500-year study period. Increasing hurricane frequency to 30 and 10 years did not significantly affect net primary productivity but resulted in a significant decrease in mean forest biomass to 61.1 ± 0.6 and 33.2 ± 0.2 Mg C/ha, respectively (p < 0.001). Hurricane events at all intervals had a positive effect on soil C stocks, although the magnitude and rate of change of soil C varied with hurricane frequency. However, the gain in soil C stocks was insufficient to offset the larger losses from aboveground biomass C over the time period. Heterotrophic respiration increased with hurricane frequency by 1.6 to 4.8%. Overall, we found that an increasing frequency of tropical hurricanes led to a decrease in net ecosystem production by − 0.2 ± 0.08 Mg C/ha/y to − 0.4 ± 0.04 Mg C/ha/y for 30–10-year hurricane intervals, respectively, significantly increasing the C source strength of this forest. These results demonstrate how changes in hurricane frequency can have major implications for the tropical forest C cycle and limit the potential for this ecosystem to serve as a net C sink.

Potential for mitigating hurricane wind impact on informally-constructed homes in Puerto Rico under current and future climate scenarios

This study investigates the resilience of informally-constructed light-frame timber houses in Puerto Rico, a region where households with limited resources face significant risks from climate hazards, notably hurricanes. This study conducts a component-based, performance-based wind engineering assessment of informally-constructed house typologies, defined based on extensive fieldwork, under both existing and projected future climate conditions. Key findings highlight the effectiveness of certain mitigation strategies, such as reinforcing roof-to-wall connections, in significantly reducing the probability of failure. Fully-mitigated cases, which involve applying mitigation measures to the roof envelope, roof-to-wall connections, and shear walls, exhibited annual probabilities of failure that are much closer to, but do not necessarily meet, the threshold targeted by American building standards (i.e., ASCE 7). The results also show a dramatic increase in probability of failure of these houses projected by the adopted climate change model scenarios, driven by the increased frequency and intensity of hurricanes in Puerto Rico. Results from feedback from those working in the informal construction sector also identify challenges hindering the effective implementation of mitigation measures in Puerto Rican communities, including a lack of knowledge about how to implement the mitigation strategies and barriers related to real and perceived costs. Taken together these results underscore the urgent need for changes in building practices and revising building standards and suggesting potentially feasible mitigation strategies to improve those practices.

Characterization of per- and polyfluoroalkyl substances (PFAS) and other constituents in MSW landfill leachate from Puerto Rico

Elevated per- and polyfluoroalkyl substance (PFAS) concentrations have been reported in municipal solid waste (MSW) landfill leachate with higher levels in wet and warmer subtropical climates. Information about landfill leachate characteristics is much more limited in tropical climates. In this study, 20 landfill leachate samples were collected from three MSW landfills on the tropical island of Puerto Rico and results were compared against landfills nationally and within Florida, USA. The samples collected in Puerto Rico underwent physical-chemical analysis, as well as a quantitative analysis of 92 PFAS. Samples described in this study include discrete leachate types, such as leachate, gas condensate, and leachate which has undergone on-site treatment (e.g., RO treatment, phytoremediation, lagoons). A total of 51 PFAS were detected above quantitation limits, including perfluorohexylphosphonic acid, a perfluoroalkyl acid (PFAA) which has not been reported previously in landfill leachate. ∑PFAS concentrations in this study (mean: 38,000 ng L−1), as well as concentrations of individual PFAS, are significantly higher than other reported MSW landfill leachate concentrations. The profiles of leachates collected from on-site treatment systems indicate possible transformation of precursor PFAS as a result of treatment processes – oxidizing conditions, for example, may facilitate aerobic transformation, increase the concentrations of PFAAs, and possibly increase the apparent ∑PFAS concentration. Extreme climate events, including rising temperatures and more frequent hurricanes, have placed additional strain on the solid waste management infrastructure on the island – adding complexity to an already challenging PFAS management issue. As concern grows over PFAS contamination in drinking water, these findings should inform solid waste and leachate management decisions in order to minimize PFAS emissions in island environments.

Succession and seasonality drive tropical butterfly assembly after an extreme hurricane

AbstractThe composition and biodiversity of insect community assemblages are mediated by a complex set of biotic and abiotic factors. Among these factors are forest structure and atmospheric variables (like temperature and humidity), which are heavily influenced by frequent hurricane activity in the Caribbean. Despite this, changes in Caribbean insect assemblages as forests recover from hurricane disturbance are poorly documented. Butterflies represent a charismatic model taxon in biodiversity and conservation, and are thus an ideal subject for exemplifying these shifts in insect abundances and diversity across ecological succession. Here, we monitored butterfly communities in two Puerto Rican forests differing in structure (i.e., canopy height, tree size) to assess butterfly diversity, abundances, and community level wing traits (size and color) over 1 year, beginning 6 months after Hurricane Maria. Monthly sampling over the course of 1 year revealed no relationships between abundances and canopy openness or humidity; instead, species abundances fluctuated seasonally and were nonlinearly correlated with temperature. In contrast, wing size and color were linearly correlated with abiotic variables. Specifically, wings were larger in cooler and more open conditions. Wing color saturation and brightness were negatively correlated with humidity. Our results suggest that, first, a functional approach may provide better insight into the factors mediating species responses to disturbances. Second, further disentangling abundance seasonality from impacts of extreme disturbances necessitates long‐term monitoring.Abstract in Spanish is available with online material.

Aftereffects of Hurricanes Irma and Ian on queen conch Aliger gigas in the Florida Keys, USA

Hurricanes can have substantial impacts on shallow-water marine habitats and species. Populations of slow-moving benthic species that are subject to depensation such as the queen conch Aliger gigas may be particularly vulnerable to hurricanes. The species is protected in Florida (USA), which allowed us to investigate the effects of Hurricanes Irma (2017) and Ian (2022) on the population without the confounding effects of fishing. Adult queen conch density had declined over 80% at sites resurveyed immediately after the passage of Hurricane Irma. Additionally, the sites closest to the eye of Hurricane Irma had a significant increase in the percent cover of sand. The sand mobilized by the storm likely buried numerous conch and caused mortality. Subsequent Florida Keys-wide annual monitoring did not show any substantial recovery in adult density prior to Hurricane Ian. Adult density had declined by &amp;#126;45% at sites resurveyed after Hurricane Ian. Unlike after Irma, we did not detect any significant correlation in the change to the percent cover of sand with distance from Ian. This was probably because the eye of Hurricane Ian was farther away from the main portion of the Keys than that of Hurricane Irma. Nevertheless, after both hurricanes, adult density dropped below the minimum threshold for mating in the Keys, demonstrating the depensatory implications of hurricanes for conch populations. Consequently, fishery managers must consider the synergistic effects of hurricanes and harvest on exploited populations, especially since the intensity, longevity, and frequency of hurricanes are expected to increase due to climate change.

The effect of repeated hurricanes on the age of organic carbon in humid tropical forest soil.

Increasing hurricane frequency and intensity with climate change is likely to affect soil organic carbon (C) stocks in tropical forests. We examined the cycling of C between soil pools and with depth at the Luquillo Experimental Forest in Puerto Rico in soils over a 30-year period that spanned repeated hurricanes. We used a nonlinear matrix model of soil C pools and fluxes ("soilR") and constrained the parameters with soil and litter survey data. Soil chemistry and stable and radiocarbon isotopes were measured from three soil depths across a topographic gradient in 1988 and 2018. Our results suggest that pulses and subsequent reduction of inputs caused by severe hurricanes in 1989, 1998, and two in 2017 led to faster mean transit times of soil C in 0-10 cm and 35-60 cm depths relative to a modeled control soil with constant inputs over the 30-year period. Between 1988 and 2018, the occluded C stock increased and δ13C in all pools decreased, while changes in particulate and mineral-associated C were undetectable. The differences between 1988 and 2018 suggest that hurricane disturbance results in a dilution of the occluded light C pool with an influx of young, debris-deposited C, and possible microbial scavenging of old and young C in the particulate and mineral-associated pools. These effects led to a younger total soil C pool with faster mean transit times. Our results suggest that the increasing frequency of intense hurricanes will speed up rates of C cycling in tropical forests, making soil C more sensitive to future tropical forest stressors.

Assessing elevated home slab retrofitting method for residential coastal buildings under hurricane loads

With an increase in the frequency and intensity of hurricanes in the United States, effective mitigation solutions should be considered by individuals and governments. This paper investigates the slab elevation retrofit method as a mitigation strategy for residential timber buildings to reduce structural damage and associated economic losses due to hurricane loads. More specifically, a holistic assessment was performed to compare the structural response for typical coastal residential buildings with and without slab elevation incorporated and assess the impact of this retrofitting scheme on the overall building performance. A detailed finite element model was generated for a typical archetype and was used to conduct dynamic analyses for various wind and flood load conditions. The results of the progressive failure analyses were then used to perform loss assessments based on the methodology of the HAZUS hurricane manual. Based on the results of this study, when implementing the slab elevation retrofit method, the damage and associated economic losses due to hurricane-induced loads were reduced. It was observed for all analysis cases that damage due to flood loading dominated the response and economic losses. A noticeable reduction in the recovery time (in days) was also obtained for the considered elevated structures.

Severe hurricanes increase recruitment and gene flow in the clonal sponge Aplysina cauliformis.

Upright branching sponges, such as Aplysina cauliformis, provide critical three-dimensional habitat for other organisms and assist in stabilizing coral reef substrata, but are highly susceptible to breakage during storms. Breakage can increase sponge fragmentation, contributing to population clonality and inbreeding. Conversely, storms could provide opportunities for new genotypes to enter populations via larval recruitment, resulting in greater genetic diversity in locations with frequent storms. The unprecedented occurrence of two Category 5 hurricanes in close succession during 2017 in the U.S. Virgin Islands (USVI) provided a unique opportunity to evaluate whether recolonization of newly available substrata on coral reefs was due to local (e.g. re-growth of remnants, fragmentation, larval recruitment) or remote (e.g. larval transport and immigration) sponge genotypes. We sampled A. cauliformis adults and juveniles from four reefs around St. Thomas and two in St. Croix (USVI). Using a 2bRAD protocol, all samples were genotyped for single-nucleotide polymorphisms (SNPs). Results showed that these major storm events favoured sponge larval recruitment but did not increase the genetic diversity of A. cauliformis populations. Recolonization of substratum post-storms via clonality was lower (15%) than expected and instead was mainly due to sexual reproduction (85%) via local larval recruitment. Storms did enhance gene flow among and within reef sites located south of St. Thomas and north of St. Croix. Therefore, populations of clonal marine species with low pelagic dispersion, such as A. cauliformis, may benefit from increased frequency and magnitude of hurricanes for the maintenance of genetic diversity and to combat inbreeding, enhancing the resilience of Caribbean sponge communities to extreme storm events.

HEvOD: A database of hurricane evacuation orders in the United States

Assessing and improving the effectiveness of evacuation orders is critical to improving hurricane emergency response, particularly as the frequency of hurricanes increases in the United States. However, our understanding of causal relationships between evacuation orders and evacuation decision-making is still limited, in large part due to the lack of standardized, high-temporal-resolution data on historical evacuation orders. To overcome this gap, we developed the Hurricane Evacuation Order Database (HEvOD) – a comprehensive database of hurricane evacuation orders issued in the United States between 2014 and 2022. The database features evacuation orders that were systematically retrieved and compiled from a wide range of resources and includes information on order type, announcement time, effective time, and evacuation area. The rich collection of attributes and the resolution of the data in the database will allow researchers to systematically investigate the impact of evacuation orders, as a vital public policy instrument, and can serve as an important resource to identify gaps in current policies, leading to more effective policy design in response to hurricanes.

Catastrophic storms, forest disturbance, and the natural history of Swainson's warbler.

The core breeding range of Swainson's warbler (Limnothlypis swainsonii) overlaps a zone of exceptionally high tornado frequency in southeastern North America. The importance of tornadoes in creating breeding habitat for this globally rare warbler and other disturbance-dependent species has been largely overlooked. This paper estimates tornado frequency (1950-2021) and forest disturbance in the 240 counties and parishes in which breeding was documented from 1988 to 2014. The frequency of destructive tornadoes (EF1-EF5) varied 6-fold across the breeding range with a peak in the Gulf Coast states. Counties from east Texas to Alabama experienced the lowest median return interval of 5.4 years per 1000 km2, resulting in approximately 2477 ha of forest damage per 1000 km2 per century, based on current forestland cover. Tornadoes were significantly less frequent north and east of the core breeding range, with return intervals increasing to 9.1 years per 1000 km2 for breeding counties on the Atlantic coastal plain, 10.2 years per 1000 km2 in the Ozark Mountains, and 32.3 years per 1000 km2 in the Appalachian Mountains. Breeding counties within 150 km of the coastline from east Texas to North Carolina are also subjected to the highest frequency of hurricanes in the Western Hemisphere. Hurricanes often cause massive forest damage but archived meteorological and forestry data are insufficient to estimate the aggregate extent of forest disturbance in breeding counties. Nevertheless, the combined impact of tornadoes and hurricanes in the pre-Anthropogenic era was likely sufficient to produce a dynamic mosaic of early-successional forest crucial for the breeding ecology of Swainson's warbler. To ensure the long-term survival of this rare warbler, it is advisable to develop habitat management plans that incorporate remote sensing data on early-successional forest generated by catastrophic storms as well as anthropogenic activities.

Climate risk in mortgage markets: Evidence from Hurricanes Harvey and Irma

AbstractUsing the Credit Risk Transfers (CRTs) issued by Fannie Mae and Freddie Mac, we study how, absent government intervention, mortgage markets would price hurricane risk. Currently, such risk is priced equally across locations even if it is location‐specific. We hand collect a novel and detailed database to exploit CRTs' heterogeneous exposure to Hurricanes Harvey and Irma. Using a diff‐in‐diff specification, we estimate the reaction of private investors to hurricane risk. We use the previous results to calibrate a model of mortgage lending. We simulate hurricane frequencies and mortgage default probabilities in each US county to derive the market price of mortgage credit risk, that is, the implied guarantee fees (g‐fees). Market‐implied g‐fees in counties most exposed to hurricanes would be 70% higher than inland counties.

Stronger Hurricanes and Climate Change in the Caribbean Sea: Threats to the Sustainability of Endangered Coral Species

An increasing sea surface temperature as a result of climate change has led to a higher frequency and strengthening of hurricanes across the northeastern Caribbean in recent decades, with increasing risks of impacts to endangered corals and to the sustainability of coral reefs. Category five Hurricanes Irma and María during 2017 caused unprecedented damage to coral reef ecosystems across northeastern Puerto Rico, including mechanical destruction, localized sediment bedload (horizontal sediment transport and abrasion), and burial by hurricane-generated rubble fields. Hurricanes inflicted significant site-, depth-, and life history trait-specific impacts to endangered corals, with substantial and widespread mechanical damage to branching species, moderate mechanical damage to foliose species, and moderate to high localized damage to small-sized encrusting and massive morphotypes due to sediment bedload and burial by rubble. There was a mean 35% decline in Acropora palmata live cover, 79% in A. cervicornis, 12% in Orbicella annularis, 7% in O. faveolata, 12% in O. franksi, and 96% in Dendrogyra cylindrus. Hurricane disturbances resulted in a major regime shift favoring dominance by macroalgae, algal turf, and cyanobacteria. Recovery from coral recruitment or fragment reattachment in A. palmata was significantly higher on more distant coral reefs, but there was none for massive endangered species. Stronger hurricanes under projected climate change may represent a major threat to the conservation of endangered coral species and reef sustainability which will require enhancing coral propagation and restoration strategies, and the integration of adaptive, ecosystem-based management approaches. Recommendations are discussed to enhance redundancy, rapid restoration responses, and conservation-oriented strategies.

Last millennium hurricane activity linked to endogenous climate variability

Despite increased Atlantic hurricane risk, projected trends in hurricane frequency in the warming climate are still highly uncertain, mainly due to short instrumental record that limits our understanding of hurricane activity and its relationship to climate. Here we extend the record to the last millennium using two independent estimates: a reconstruction from sedimentary paleohurricane records and a statistical model of hurricane activity using sea surface temperatures (SSTs). We find statistically significant agreement between the two estimates and the late 20th century hurricane frequency is within the range seen over the past millennium. Numerical simulations using a hurricane-permitting climate model suggest that hurricane activity was likely driven by endogenous climate variability and linked to anomalous SSTs of warm Atlantic and cold Pacific. Volcanic eruptions can induce peaks in hurricane activity, but such peaks would likely be too weak to be detected in the proxy record due to large endogenous variability.

Giant mobile coralliths from the Florida Keys, USA

Coralliths are spherical, free-living (motile), scleractinian colonies inhabiting present day and ancient coral reefs. They form by the coral rolling on the seabed which can occur through biological and/or physical processes. While diving and snorkeling in nearshore environments in the upper Florida Keys, we observed hundreds of coralliths of varying sizes and species. This included colonies of Porites astreoides, Siderastrea radians, and Solenastrea bournoni. The largest coralliths we observed were all S. bournoni and ranged between 0.5 and 1.4 m in diameter. The exceptionally large colonies identified (&gt;1 m) may be the largest and oldest spherical coralliths described to date. Relatively frequent movement of a corallith is key to their formation as all colony surfaces must be exposed to sunlight and currents periodically to maintain their spherical shape. Intuitively, the larger a corallith grows, the stronger the current energy must be to initiate movement. Considering the shallow depth of the corallith habitat and the high frequency of tropical storms and hurricanes impacting south Florida, we hypothesized that the forces generated by shoaling, breaking storm waves would be sufficient to cause the formation of these giant coralliths. Calculations based on hydrodynamic forces and field observations after the passage of a storm support the efficacy of storm-generated waves and surge to move and roll these giant coralliths. The tropical storm/hurricane return time where we found these large colonies in the Florida Keys is one in every seven years. This return time is apparently frequent enough to maintain their spherical morphology and assist in the formation of these giant coralliths.

The Impact of Projected Changes in Hurricane Frequencies on U.S. Hurricane Wind and Surge Damage

Abstract We use a simple risk model for U.S. hurricane wind and surge economic damage to investigate the impact of projected changes in the frequencies of hurricanes of different intensities due to climate change. For average annual damage, we find that changes in the frequency of category-4 storms dominate. For distributions of annual damage, we find that changes in the frequency of category-4 storms again dominate for all except the shortest return periods. Sensitivity tests show that accounting for landfall, uncertainties, and correlations leads to increases in damage estimates. When we propagate the distributions of uncertain frequency changes to give a best estimate of the changes in damage, the changes are moderate. When we pick individual scenarios from within the distributions of frequency changes, we find a significant probability of much larger changes in damage. The inputs on which our study depends are highly uncertain, and our methods are approximate, leading to high levels of uncertainty in our results. Also, the damage changes we consider are only part of the total possible change in hurricane damage due to climate change. Total damage change estimates would also need to include changes due to other factors, including possible changes in genesis, tracks, size, forward speed, sea level, rainfall, and exposure. Nevertheless, we believe that our results give important new insights into U.S. hurricane risk under climate change. Significance Statement We investigate how changes in the frequencies of hurricanes of different intensities as a result of climate change may contribute to changes in U.S. economic damage due to wind and surge. We find that economic damage will likely increase as a result of projected increases in the frequency of landfalling hurricanes. Analysis of our results shows that increases in the frequency of category-4 storms are the main driver of the changes. Our best estimate results, based on a multimodel ensemble, give modest increases in damage, but within the ensemble there are individual scenarios that give much larger increases in damage. The large range of individual damage estimates is a motivation for continuing efforts to reduce the uncertainty around hurricane projections under climate change.

More Frequent Hurricane Passage Across the Bahamian Archipelago During the Little Ice Age

AbstractThe year 2020 Common Era (CE) experienced the highest number of named tropical cyclones in the Atlantic Ocean since 1850 CE, but the short instrumental record makes it challenging to assess if this level of activity is statistically meaningful. Here, we present two near‐annually resolved hurricane reconstructions from sediment archived in two blue holes located only 300 m apart on the northern margin of Grand Bahama. These two blue holes provide a replicated signal of hurricanes passing within a 50–100 km radius over the last 1,800 years, and the long‐term reconstructions document multiple 50‐to‐150‐year intervals when hurricane frequency was significantly higher than it has been over the last 100 years. These two records were first merged into a single stack, and then compiled with five other high‐resolution reconstructions from across the Bahamian Archipelago to form a single 1500‐year record of Bahamian hurricane frequency. This new Bahamian Compilation documents more hurricanes passing ∼75°W from 21°N to 26°N during the Little Ice Age (LIA; 1300–1850 CE) relative to the prior millennium and the last 170 years. The US Eastern Seaboard also experienced heightened hurricane activity during the LIA, whereas the Gulf of Mexico and Southern Caribbean were inactive. This suggests that despite a globally cooler climate, regional climate conditions during the LIA remained favorable for cyclogenesis and intensification along certain Atlantic hurricane pathways. Perhaps heightened Sahel rainfall during the LIA indicates an increase in African Easterly waves, which in turn possibly seeded more tropical cyclones in the Atlantic Main Development Region.

Hurricane wind regimes for forests of North America

Despite the ubiquity of tropical cyclones and their impacts on forests, little is known about how tropical cyclone regimes shape the ecology and evolution of tree species. We used a simple meteorological model (HURRECON) to estimate wind fields from hurricanes in the Western North Atlantic and Eastern North Pacific tropical cyclone basins from storms occurring between 1851 and 2022. We characterize how the intensity and frequency of hurricanes differ among geographically distinct hurricane regimes and define four hurricane regimes for North America (Continental, Inland, Coastal, and Fringe). Along this coastal-to-inland gradient, we found major differences in the frequency and intensity of hurricane wind regimes. The Fringe regime experiences category 1 winds relatively frequently [return period (RP) 25 y], whereas the Inland regime experiences category 1 winds very infrequently (RP ~3,000 y). We discuss how species traits related to tree windfirmness, such as mechanical properties and crown traits, may vary along hurricane regime gradients. Quantitative characterization of forest hurricane regimes provides a critical step for understanding the evolutionary and ecological role of hurricane regimes in wind-prone forests.