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Tropical cyclone (TC)-induced rainfall is one of the most extreme rain phenomena, usually resulting in severe flooding and inundation when a TC makes landfall and is still considered the biggest challenge for TC forecasting. This study focuses on developing a R-CLIPER (Tropical Cyclone Rainfall Climatology and Persistence) model for TC-induced rainfall forecasting over the Vietnam region using precipitation data from GSMaP (Global Satellite Mapping of Precipitation) and TRMM (The Tropical Rainfall Measuring Mission). We used the best track data for 199 TCs affecting the Vietnam region during the period 2000–2021, obtained from the Regional Specialized Meteorological Center (RSMC) Tokyo Typhoon Center. The performance of the established R-CLIPER models for TC rainfall forecasting was assessed under different circumstances by categorizing the rain thresholds and TC intensities. The evaluations are conducted by comparing the 24-hour R-CLIPER model's rainfall forecast against satellite-estimated and surface-observed rains, indicating a reasonable prediction of two model versions, namely, the R-GSMaP and R-TRMM models, with slight outperformance of the R-GSMaP over the R-TRMM model. In detailed analyses of three case studies, we found that the results of predicted TC-induced rainfall largely vary depending on both weather conditions and TC tracks. In addition, using the developed R-CLIPER model as a baseline, we evaluate the performances of three global NWP models in TC-induced rainfall prediction by calculating a percentage of improvement in the statistical scores over those of the R-CLIPER model. The results revealed the greatest improvement in the forecast by the Integrated Forecasting System (IFS) model. [ABSTRACT FROM AUTHOR]

The article "Remnants--Hurricane Debby (2024) and Far Beyond" from the Journal of Psychohistory discusses the destructive path of Hurricane Debby in August 2024, which caused widespread devastation along the U.S. east coast and into Canada. The text reflects on the aftermath of the hurricane, drawing parallels to historical events and questioning whether remnants of past catastrophes can ever truly become history rather than prophecy. The author, Howard F. Stein, explores the concept of recurring storms and their lasting impact on society, urging readers to consider the implications of these remnants on our collective future. [Extracted from the article]

Tropical cyclones (TCs) pose a substantial threat to human life and property, with China being among the most affected countries. In this study, a significant increasing trend is detected for TC destructiveness, primarily measured by precipitation, and for TC‐induced damage, measured by direct economic losses (DELs), in the inland areas of East China. In contrast, a similar trend cannot be observed in the coastal regions. The rapid increase of TC‐induced damage in the inland areas of East China is directly related to an increase of the annual number of disastrous TCs, which is a result of the increased TC landfall frequency and the increased TC decay timescale after landfall. The increase in specific humidity, soil moisture, and the decrease in vertical wind shear in East China favor the survival of TCs inland. Our results highlight the significance of TC disaster prevention in the inland regions. Plain Language Summary: The damage induced by tropical cyclones (TCs) shows a long‐term increasing trend in mainland China. In general, the occurrence of TC disasters is more frequent in coastal areas than inland. However, inland areas lack resilience toward TC attacks, resulting in substantial damage when a TC reaches. This study focuses on the long‐term variations of TC destructiveness and the damage that results in inland areas, and a significant increasing trend has been observed, particularly in East China. The rapid increase of TC‐induced damage in the inland areas of East China is essentially due to the increased annual number of disastrous TCs in this region. Such an increase of the disastrous TC number is not only attributed to the increasing TC landfall frequency but also related to the increasing post‐landfall TC decay timescale. It is further demonstrated that the increase in specific humidity, soil moisture, and the decrease in vertical wind shear in East China favor the survival of TCs in inland areas. Our findings highlight the significance of TC disaster prevention in the inland areas. Key Points: A significant increasing trend is detected for TC destructiveness and its resulting damage in the inland areas of East ChinaThe increase of TC‐induced damage is primarily due to an increase in the annual number of disastrous TC eventsThe increase in disastrous TC events is related to an increase in TC landfall frequency and in decay timescale of TCs after landfall [ABSTRACT FROM AUTHOR]

This study quantified the relative impact of microphysics parameterization (MP) and cumulus parameterization (CP) schemes on storm prediction using a non‐hydrostatic weather research and forecasting model for an intense Medicane: IANOS. All the simulations agreed with the main observed characteristics of this storm, with some discrepancies in magnitude and location, which vary with CP and MP schemes. These discrepancies were larger during the mature phase of the storm. In the CP‐on simulations, the non‐scale aware Kain–Fritsch (KF) scheme typically resulted in higher precipitation, while the Betts‐Miller‐Janjic (BMJ) scheme led to lower precipitation compared to the CP‐off simulations (C0). The tendency of the KF scheme to consume available convective potential energy at a relatively high rate (i.e., short time scale) resulted in high mass fluxes and latent heat release, leading to strengthened convective activity and, hence, precipitation. The multi‐scale aware (MSKF) substantially reduces the precipitation compared to KF due to the reduced contribution of convective scale precipitation. It also modulates the spatial structure precipitation compared to KF, especially light precipitation over the outer bands, and the contribution of grid‐scale precipitation to total precipitation. KF shows the lowest contribution, around 50%, whereas BMJ exhibits a slightly higher contribution, and MSKF versions nearly reach 100%, making it closer to CP‐off. The improved performance in MSKF compared to KF highlights the importance of MSKF convection parameterization for gray zone (~1–4 km) simulation. The persistent discrepancy in landfall location in CP‐on and CP‐off simulation underscored the need of further investigating other physics parameterizations and dynamical mechanisms. Plain Language Summary: This study made an effort to unravel model sensitivity to microphysics parameterization (MP) and cumulus parameterization in convection‐permitting simulations, considering as a case study the intense cyclone "IANOS" that passed over the Mediterranean Sea. All simulations agreed with the main observed storm characteristics, though high‐resolution observations are still lacking to increase the results' confidence. The multi‐scale aware substantially reduces the precipitation compared to non‐scale aware Kain–Fritsch due to the reduced contribution of convective scale precipitation; however, the magnitude of the precipitation reduction varies its pairing with MP, indicating how the need for careful selection of microphysics and cumulus schemes is crucial. None of the sensitivity experiments successfully reproduced the accurate storm landfall location, prompting the need for additional research about the influence of alternative physics parameterizations such as planetary boundary layer and radiation as well as exploring other dynamical processes such as air‐sea coupling. Key Points: Simulations of Medicane IANOS at 3 km horizontal resolution are highly sensitive to microphysics and cumulus parameterization schemesMulti‐scale aware Kain–Fritsch (MSKF) improves the performance compared to Kain–Fritsch, which varies with microphysics parameterizationsMSKF's ability to generate optimal contributions of convective and grid‐scale precipitation makes it effective for gray zone (~1–4 km) simulation [ABSTRACT FROM AUTHOR]

The inner core of a typhoon plays a crucial role in storm intensification and is especially critical for rapid increases in storm intensity. Most of the energy exchange occurs in the inner core, including the eyewall. Moist air rising from the warm ocean releases latent heat, increasing wind speeds and sustaining the warm-core structure through secondary circulations. A deeper understanding of the physical processes in the inner core is essential for improving intensity forecasts and disaster preparedness and mitigation. This paper reviews key studies on the inner core. We focus on lead–lag relationships, eyewall replacement cycles, and waves and oscillations, which are topics that can greatly enhance forecasting capabilities. We highlight limitations of current research and propose key scientific questions that would provide essential insights to improve forecasts and support disaster reduction strategies. These include: (1) what are the physical processes that drive the lead–lag relationship between eyewall convection and intensity changes, and how does the time lag vary across typhoons? (2) What conditions favor merging of the inner and outer eyewalls and completion of the eyewall replacement cycle, potentially leading to rapid intensification before landfall? (3) How do waves and oscillations in the eyewall influence typhoon intensity variations? [ABSTRACT FROM AUTHOR]

Utilizing the best typhoon track data, district and county scale disaster data in Jilin Province, meteorological data, and geographical data, the combined weighting method of AHP-EWM (Analytic Hierarchy Process–Entropy Weight Method) and game theory is employed to conduct a comprehensive risk analysis and comparison of the disaster risk caused by two typhoons, Maysak and Haishen, in Jilin Province. Game theory enhances precision in evaluation beyond conventional approaches, effectively addressing the shortcomings of both subjective and objective weighting methods. Typhoon Maysak and Typhoon Haishen exhibit analogous tracks. They have successively exerted an impact on Jilin Province, and the phenomenon of overlapping rain areas is a crucial factor in triggering disasters. Typhoon Maysak features stronger wind force and greater hourly rainfall intensity, while Typhoon Haishen has a longer duration of rainfall. Additionally, Typhoon Maysak causes more severe disasters in Jilin Province. With regard to the four dimensions of disaster risk, the analysis of hazards reveals that the areas categorized as high risk and above in relation to the two typhoons are mainly located in the central-southern and eastern regions of Jilin Province. Typhoon Maysak has a slightly higher hazard level. During the exposure assessment, it was determined that the high-risk areas occupied 16% of the gross area of Jilin Province. It is mainly concentrated in three economically developed cities, as well as some large agricultural counties. In the context of vulnerability analysis, regions classified as high risk and above constitute 54% of the overall area. The areas classified as having high vulnerability are predominantly located in Yushu, Nong'an, and Songyuan. From the analysis of emergency response and recovery ability, Changchun has strong typhoon disaster prevention and reduction ability. This is proportional to the local level of economic development. The mountainous areas in the east and the regions to the west are comparatively weak. Finally, the comprehensive typhoon disaster risk zoning indicates that the zoning of the two typhoons is relatively comparable. When it comes to high-risk and above areas, Typhoon Maysak accounts for 38% of the total area, while Typhoon Haishen occupies 47%. The regions with low risk are predominantly found in Changchun, across the majority of Baicheng, and at the intersection of Baishan and Jilin. Upon comparing the disasters induced by two typhoons in Jilin Province, it was observed that the disasters caused by Typhoon Maysak were considerably more severe than those caused by Typhoon Haishen. This finding aligns with the intense wind and heavy rainfall brought by Typhoon Maysak. [ABSTRACT FROM AUTHOR]

In this study, a super cyclonic storm (Amphan) over Bay of Bengal was analyzed with the National Center for Medium-Range Weather Forecasting, Unified Model (NCUM) and National Center for Environmental Prediction (NCEP) global model data. Further, the weather research and forecasting (WRF) model has been utilized to simulate this super cyclonic storm with NCUM and NCEP data as initial and boundary conditions. The model is integrated, for every 12 h interval from 16 May 0000 UTC to 18 May 1200 UTC with horizontal resolution of 9 km and vertically at 34 levels. The results reveal that the track of the cyclone, central pressure of the cyclone, intensity of the cyclone, and landfall time of the cyclone are simulated by the model reasonably well in both the cases that are with NCUM-GFS and NCEP-GFS. However, the WRF simulations with NCEP data are closer to IMD's estimated track and intensity, when compared with the simulations with NCUM data. The relatively higher errors in simulations with NCUM could be due to the differences in the initial cyclone vortex against the observation in some initial conditions. [ABSTRACT FROM AUTHOR]

This study reveals the possible future changes in tropical cyclone (TC) landfalling activity along the East Asian coast under different climate change scenarios based on global circulation model (GCM) simulations. We first identify those GCMs that have the "best" performance in simulating the TC activity over the western North Pacific (WNP) during the current climate (1979-2014) by examining the simulated TCs in each of the GCMs and then compare these simulated TCs with the observed TC climatological features of annual frequency, track densities and genesis locations. Based on such comparisons, we have identified five (TaiESM1, EC-Earth3, ACCESS-CM2, ACCESS-ESM1-5 and HadGEM3-GC31-LL) models among all the available GCMs. A multi-model ensemble gives a further improvement when compared with observations. Future projections from some of these models are then used to identify the frequency of TC activity over the entire WNP as well as landfalling TCs in six East Asia coastal regions under two climate change scenarios (SSP2-4.5 and SSP5-8.5) for two periods, 2041-70 and 2071-2100. A bias-correction method is also applied to the projected intensity of these landfalling TCs to estimate the landfall intensity. In general, these GCMs project a possible decrease in TC genesis frequency over the entire WNP, consistent with the results of most of the other studies. At mid-century, decreases in TC genesis frequency are projected to be around 10% for both scenarios. Towards the end of the century, the decreases will be more significant, with the percentage changes of 14.9% (SSP2-4.5) and 22.4% (SSP5-8.5). For landfalling TCs, the northern part of the East Asian coast will likely have an increase in frequency, ranging from 17 to 60% but a decrease of 14-27% in the southern part. In general, the average intensity of landfalling TCs will likely increase although the percentages are not large, ranging from 2 to 14%. [ABSTRACT FROM AUTHOR]

During February-March 2023, the record-breaking tropical cyclone (TC) Freddy caused widespread flooding and damages across southeastern Africa. While <5 % of TCs make landfall into southern Africa, TC Freddy made landfall twice and is the only TC in the past two decades that has tracked over 8000 km across the entire southern Indian Ocean. To understand why TC Freddy was so unique, this study investigated the evolution, track and atmospheric-oceanic mechanisms driving TC Freddy using the ERA5, CFSv2, OSTIA, NCEP-NCAR datasets and track data from various sources. It was found that SSTs were >27 °C during TC Freddy's lifetime, while TC Dingani and a split Mascarene High played a role in steering TC Freddy across the southern Indian Ocean. Leading up to the development of TC Freddy, conditions were favourable for TC genesis, as indicated by the levels of the Genesis Potential Parameter (GPP) and its modified version (GPPI), the tropical cyclone heat potential levels, and elevated SSTs. Ridging subtropical anticyclones and the Mascarene High alongside favourable steering flow and GPP (and GPPI) conditions resulted in Freddy's double landfall in Mozambique. In assessing the tracks, it was found that there are discrepancies in the track of the commonly used IBTrACS when compared to ERA5 and RSMC tracks, which has implications for impact studies due to the underestimation of landfall considerations. This study reveals the unique characteristics and atmospheric-oceanic mechanisms driving TC Freddy, emphasising the importance of accurate representation of favourable conditions and track data for enhancing TC forecasting and impact assessments. [ABSTRACT FROM AUTHOR]

Hurricane Nicholas was classified as a Category 1 tropical cyclone (TC) at 0000 UTC on 14 September 2021 and made landfall along the upper Texas Gulf Coast at 0530 UTC with maximum sustained winds of 33 m s−1. Much of the electrical activity during Nicholas was monitored by the Houston Lightning Mapping Array (HLMA) network. Thunderstorm activity developed in the rainband at 1700 UTC on 13 September, diminished by 2030 UTC, and re‐intensified after 2200 UTC. At 2004 UTC (13 September), a curved megaflash (∼220 km) was observed by the HLMA in the stratiform precipitation region of the outer rainband. By 0130 UTC on 14 September 2021, vigorous storm cells developed in the eastern eyewall region and propagated cyclonically to the western eyewall region. At least four "jet‐like" transient luminous events (TLEs) were observed by the HLMA emanating from a storm cell in the western eyewall region between 0230 and 0300 UTC with VHF source points ranging from 30 to 45 km in altitude. Moreover, the TLEs occurred within a region of strong wind shear, upper‐level graupel‐ice crystal collisions (∼15 km), and strong cloud top divergence. Charge analysis of the thunderstorm activity during Nicholas revealed an overall normal dipole structure, while the megaflash and TLE cases exhibited inverted dipole charge structures. Dissipation of the upper‐level screening charge layer resulting from cloud top divergence likely played a role in the observed TLE VHF sources escaping to altitudes exceeding 30 km. Plain Language Summary: Hurricane Nicholas rapidly intensified and impacted the Texas Gulf Coast just after midnight on 14 September 2021. Nicholas moved inland southwest of Houston and rapidly weakened throughout the day. Powerful low‐ and mid‐level winds blew counterclockwise around the eye while upper‐level winds were blowing from the southwest. This created wind shear and removal of upper‐level air, or divergence, which helped to intensify updrafts and thunderstorm development in the rainband and eyewall. The Houston Lightning Mapping Array, a network of lightning detectors, identified frequent lightning activity within the rainband a few hours before Nicholas became a hurricane. The thunderstorms in the rainband produced a large, curved "megaflash" that was 220 km across. Vigorous eyewall lightning activity was observed a few hours after Nicholas was designated as a hurricane. The thunderstorms in the eyewall produced rarely observed lightning, called transient luminous events. This type of lightning travels upwards from the tops of the thunderclouds toward space. The wind shear along with the timing and location of the lightning events gave important clues about Nicholas' intensification. The results of this study can be used in future efforts to investigate hurricane strengthening and potential impacts. Key Points: A megaflash and at least four transient luminous events were observed as Hurricane Nicholas approached the Texas Gulf CoastStrong cloud top divergence of air parcels, wind shear, and moisture impact the location and magnitude of lightning activityCharge structure evolution in tropical convection reflects physical processes related to the likelihood of rare lightning events [ABSTRACT FROM AUTHOR]

The Ang Pagtanom og Binhi Project is a University–Community partnership and community-based participatory research project exploring the health benefits of food sovereignty practices in the Philippines. In late 2021, in the midst of data collection, Super Typhoon Odette made landfall in the Philippines causing massive environmental and structural devastation. In the aftermath of the storm, community partners in the Philippines and members of the research team in the United States shared photos, texts, and updates. These messages included descriptions of structural and environmental damage caused by the storm and stories of mutual aid efforts and actions taken by individuals and small organizations, each highlighting connections between food sovereignty efforts in the Philippines and the impacts of climate change. Due to the richness of the stories, the interconnectedness between these conversations and the research topic, and the alignment within the theoretical foundations of the project, the researchers understood that these communications should be included as data. With feedback from the Community Advisory Board, the Research and Design Team amended project protocols, research questions, and consent forms to incorporate this emergent data. This manuscript describes the process that the team undertook and some of the lessons learned by taking this approach. [ABSTRACT FROM AUTHOR]

Hurricane Ian in 2022 was a destructive category 4 Atlantic hurricane striking the state of Florida, which caused hundreds of deaths and injuries, catastrophic property damage, and an economic loss of more than $112 billion. Before the landfall of Ian in Florida, the state government issued evacuation orders in high-risk zones to reduce casualties and injuries. However, there is limited data available to monitor the actual evacuation patterns and compliance with the evacuation orders at a large geographic scale. This study utilizes human mobility data (i.e. SafeGraph Weekly Pattern) to analyse the spatial patterns of evacuation during Hurricane Ian in 2022. The objectives of the study include three key aspects: 1) proposing an analytical workflow that utilizes human mobility data to detect mobility patterns in disasters and other emergency events; 2) identifying significant evacuation patterns, and 3) revealing the spatial variations in the compliance with evacuation orders in the affected areas. Using data science and spatial analysis techniques, this study detected notable changes in population movements, both within Florida and nationwide, which are potentially linked to the hurricane-induced population evacuation. The distance decay pattern of population flows from Florida demonstrates a propensity for individuals to relocate to nearby areas during the hurricane. Furthermore, the increase in population outflows from the impacted areas suggests the effectiveness of mandatory evacuation orders. A more pronounced increase in outflows from designated mandatory evacuation areas points to the public awareness of the evacuation zone designation. This study provides large-scale, fine-resolution analysis of evacuation behaviours in natural disasters which cannot be easily detected in traditional data sources. The analytical workflows provide actionable tools for government agencies and policymakers to evaluate the effectiveness of evacuation orders and improve evacuation plans in future disasters. [ABSTRACT FROM AUTHOR]

Previous work identified hurricane deposits in the back-barrier lagoon of Laguna Playa Grande (LPG) in Vieques, Puerto Rico, dating back over 5000 years, with periods of increased storm-induced overwash activity attributed to variability in regional hurricane climatology. In 2017, Hurricane Maria made direct landfall on LPG just below category 5 strength, providing the opportunity to revisit the site to improve upon interpretations of storm-induced deposition. Maria caused widespread wave-induced overwash of the barrier beach and extensive mangrove mortality with roughly a 40% reduction in vegetative cover along the barrier. Sediment trapping and overwash deposition occurred within ripped up and broken mangrove debris during the hurricane, which prevented sediments from being carried further landward into the lagoon. Thus, no measurable overwash deposition was observed in the larger, western portion of the lagoon where previous hurricane reconstructions are derived. Significant overwash deposition (1–27 cm thick) was observed in the smaller, eastern portion of the lagoon where human cut paths through the mangroves allowed for unobstructed flow. Early historical photos support 53% reduced vegetation in 1936 followed by revegetation towards present day that prevented sandy overwash deposits from Maria in the western side, explaining the discrepancy between previously observed hurricane overwash record compared to restricted deposition solely to locations with modern footpaths for Maria. Hurricanes occurring during the recovery-revegetation phase of such storms likely result in greater overwash deposition in back-barrier lagoons due to less barrier vegetation relative to periods with robust mangrove vegetation cover. Results highlight the important role of fringing mangrove forests in flood mitigation, and the vulnerability of back-barrier environments to enhanced flooding following both anthropogenic and event-driven vegetation loss. [ABSTRACT FROM AUTHOR]

After landfall, tropical cyclone (TC) remnants may maintain or even rejuvenate and incur catastrophic disasters. What leads to the revival of TC remnants over land remains elusive. In this study, the revival mechanism of Typhoon Doksuri (2023) remnants is extensively explored. Doksuri brought severe damage to the Chinese mainland after its landfall. The remnants vortex of Doksuri sustained an inland trajectory for 3 days and underwent a total maintenance of 60 h, with a revival of 18 h. Based on multi-source observations and ERA5 reanalysis data, by calculation of moist potential vorticity and analysis of slantwise vorticity development (SVD), this study unveils that while maintaining a significant warm-core structure over the course of maintenance and revival, the Doksuri remnants transported sufficient moisture in the mid–lower troposphere, which intensified the north–south temperature and humidity gradients, causing tilting of the isentropic surfaces remarkably. According to the SVD theory, the tilting gave rise to vorticity development and forced upward air motion on the northern side of the remnant vortex. Moreover, numerical sensitivity experiments based on the WRF model reveal that the topography of Taihang Mountains and the diabatic heating associated with surface and convective latent heat fluxes also played important roles in the revival of the Doksuri remnants. The dynamic and thermodynamic mechanisms derived by this study will help improve understanding and prediction of the disasters induced by TC remnants. [ABSTRACT FROM AUTHOR]

India's coastal states are particularly susceptible to tropical cyclones, frequently occurring and directly impacting human life and property. According to the National Cyclone Risk Management Project (NCRMP), managing cyclones in India's coastal states consumes nearly 2% of India's GDP and 12% of federal government revenue. Areas of the country vulnerable to cyclones are home to more than 37 million people. When compared to other regions of the world, the Bay of Bengal exhibits the highest number of cyclone formations, indicating that it is a region that is very prone to cyclone occurrences. Nearly 20% of all major cyclones that struck India's east coast made landfall in Odisha, mainly from April to May and September to November. The State Disaster Management Authority (OSDMA) reports that in the previous 20 years, Odisha has experienced ten cyclones. A powerful cyclone hits the coast of Odisha around every two to three decades. This study will examine various structural and nonstructural mitigation strategies that mitigate and prevent tropical cyclones' effects in the Odisha region. This study intends to develop a comprehensive framework for cyclone mitigation in the coastal state of Odisha, India, by integrating structural and non-structural measures to enhance resilience and reduce cyclone-related risks. [ABSTRACT FROM AUTHOR]

This study projects the changes in tropical cyclone (TC) landfalls in the western North Pacific under shared socioeconomic pathway (SSPs) scenarios during the TC peak season by using low‐resolution global climate models participating in the Coupled Model Intercomparison Project phase 6 (CMIP6). Projections are based on the relationship between mid‐ and lower‐level atmospheric circulation and TC landfall frequency during the historical period from 1985 to 2014 and the future climate period from 2015 to 2100. The landfall areas for TCs are divided into northern East Asia (NEA), middle East Asia (MEA) and southern East Asia (SEA); the TC peak seasons are July–September for NEA and MEA, and July–November for SEA. To evaluate reproducibility, both ensemble and individual model outputs for mid‐ and lower‐level atmospheric circulations associated with TC landfall in each East Asian subregion are compared to the reanalysis. An ensemble of seven models with stable results for all three regions is more reasonable in simulating atmospheric circulation patterns than an ensemble of all CMIP6 models. The findings suggest that TC landfall is projected to increase by about 12% and 32% in NEA and MEA, respectively, in the late 21st century under the SSP5‐8.5 scenario compared to the historical period, while decreasing by 13% in SEA. These changes are consistent under both warming scenarios, and are more pronounced in the SSP5‐8.5 scenario compared to SSP1‐2.6, particularly in the later period of this century. An analysis of future atmospheric circulations suggests that global warming will weaken the western North Pacific subtropical high and cause its boundary to retreat eastward. This will lead to changes in the steering flow, which is closely related to TC tracks, resulting in TC landfalls to increase or decrease depending on the East Asian subregion. [ABSTRACT FROM AUTHOR]

Population displacement from Puerto Rico to the United States following Hurricane Maria is considered and distinguished from ongoing outmigration from the island. Administrative data from two sources is used to estimate displacement with a capture-recapture method which, unlike existing estimates, excludes outmigration that occurs independent of the hurricane. The estimates are compared with preceding trends in outmigration from the US Census Bureau. The results show that nearly 90,000 individuals or about 2.7% of Puerto Ricans (95% CI: 2.5%, 2.9%) were displaced through May 2018. Displacement was highest (approximately 4.7%) from southeastern Puerto Rico where the hurricane made landfall and, counter to earlier outmigration patterns indicated by data from the American Community Survey, was comparatively low from the region near San Juan (4.0% pre-hurricane outmigration against 2.4% post-hurricane displacement). Displacement rates were higher in areas with higher levels of Federal Emergency Management Agency-certified damage to housing (3.3% in areas with high damage against 2.2% in areas with low damage) but did not consistently differ by indicators of socioeconomic disadvantage, including poverty and unemployment rates. Households’ intent to return indicates that those who will not return are more likely to be younger or be unemployed (86% of individuals under the age of 30 will not return, whereas 58% of individuals aged 65 and up will not return, and 84% of employed households will return, whereas 68% of unemployed ones will); these characteristics align with those commonly observed among outmigrants in the decade prior to the hurricane. [ABSTRACT FROM AUTHOR]

Based on the 6‐hourly tropical cyclone best track and global reanalysis data, statistical analyses and a machine learning approach are used to identify/quantify factors that affect the relative weakening rate (RWR) of landfalling TCs (LTCs) over China mainland during 1980–2020. Results show that the enhanced RWR of LTC events usually occurs when LTCs move into regions with large environmental vertical wind shear (VWS), large surface roughness (SURR), high land surface soil temperature (SOILT), low surface latent heat flux (SLHF), and with relatively faster translational speeds (SPD). The SPD and SURR are dominant factors determining the RWR of LTCs over China mainland, contributing about 20% and 18.5% to the RWR of LTCs. VWS is also a key factor affecting RWR of LTCs with mid‐level VWS contributing 17.8% to RWR of LTCs and low‐ and deep‐level VWS contributing about 12.9% and 11.2%, respectively. Furthermore, factors affecting the LTC weakening rate in south and north China are different. In north China, the VWS at different levels are all highly correlated with LTC RWR after landfall, whereas the influence of mid‐layer VWS shows significant correlation with LTC RWR in south China. In addition, surface characteristics, including SURR, SLHF, and SOILT, have significant correlation with LTC RWR in south China. But the relationships between surface characteristics and LTC RWR in north China are not statistically significant. It is worth noting that although the correlation between DIV200 and LTC RWR is insignificant for the whole China mainland, it presents highly negative and positive correlations in south and north China, respectively. Plain Language Summary: In this study, statistical analyses and a machine learning approach (XGBoost) are used to identify and quantify factors affecting the relative weakening rate (RWR) of landfalling tropical cyclones (LTCs) in China mainland. Results show that the large environmental vertical wind shear (VWS, no matter in the deep‐layer or in the lower‐layer), large surface roughness (SURR), high land surface soil temperature (SOILT), low surface latent heat flux (SLHF), and faster translational speed (SPD) are key factors, which enhanced the weakening rate of LTC over China mainland. Among them, the SPD and SURR play the most important role in the LTC weakening rate over China mainland. Furthermore, factors affecting LTC weakening rate in south and north are explored. In south China, LTC weakening rate highly correlated with the surface conditions (including SLHF, SOILT, and SURR), upper‐level divergence (DIV200), and SPD. However, the main factors affecting LTC weakening rate over North China are dynamical variables, including VWS, DIV200 and SPD. Although the correlation between DIV200 and LTC RWR is insignificant for the whole China mainland, it presents highly negative and positive correlations in south and north China, respectively. Key Points: A machine learning approach is used to quantify factors affecting the weakening rate of landfalling TCsThe translation speed of TCs and the surface roughness contribute most to the weakening rate of LTCs over China mainlandThe effect of upper‐level divergence to the weakening rate of LTCs is opposite over south and north China [ABSTRACT FROM AUTHOR]

This study analyses the landfall intensity of tropical cyclones (TCs) affecting the Pacific coast of Japan and found that the proportion of strong typhoons increased significantly in the second 22 years from 1977 to 2020. With an objective cluster analysis of TC tracks, one could isolate a cluster of TCs originating from the southeastern part of the western North Pacific (WNP), which plays a dominant role in increasing landfalls of strong typhoons. These TCs are characterized by a long‐recurving track and could achieve significantly higher intensity and larger size. Further analysis of TC trajectories and the environmental steering flow show a greater tendency for TCs originating from the southeastern WNP to approach the Pacific coast of Japan, even though there was a dramatic decrease in TC genesis number during autumn. Meanwhile, a notable earlier onset of strong typhoons occurred within this cluster of TCs due to more favorable atmospheric and oceanic conditions in summer. The results of this study emphasize the impacts of TC track change and seasonal advance of strong typhoons on the variation of intensity and potential destructiveness of landfalling TCs. [ABSTRACT FROM AUTHOR]

The North Indian Ocean (NIO) is one of the areas with the highest frequency of tropical cyclones (TCs) occurrence in the world. This study explores the spatial distribution patterns of North Indian Ocean tropical cyclone (NIOTC) trajectories and examines the relationship between the South Asian summer monsoon index (SASMI) and NIOTC using historical data spanning from 1959 to 2020. The annual average number of NIOTC is 4.92, with the highest frequency of occurrence being in the collection of cyclonic storms (34–47 kt) and severe cyclonic storms (48–63 kt). Based on the divergent and convergent trends in the interannual quantity sequences of SASMI and NIOTC, their relationship is categorized into two phases: positive and negative, each spanning 32 and 29 years, respectively. During the positive phase, the landfall frequency and the average intensity of TCs on the eastern coast of India are generally higher and the frequency of TCs' trajectories in the northeast Arabian Sea is significantly higher than during the negative phase, with an average difference of 19.13 trajectories within the range of 14°N-24°N and 61°E-73°E. While NIO is more inclined to generate stronger TCs during the positive phase, extremes are more likely to occur during the negative phase. [ABSTRACT FROM AUTHOR]

While tidal marshes are valued for their ability to reduce the impact of storm waves on shores, there is still more limited understanding of how storm waves impact the integrity of tidal marshes, particularly in mudflat‐marsh transition zones with patchy vegetation cover. This study aims to investigate changes in hydrodynamics, sediment bed elevation, and patchy vegetation cover along the sea‐to‐land elevation gradient in response to super typhoon IN‐FA, making landfall in 2021 in a mudflat‐marsh transition zone of the Yangtze Estuary (China). Utilizing in‐situ measurements and drone surveys, our results show: (1) A landward decrease in storm‐induced wave energy, flow velocities, turbulence, and erosion across a 200‐m mudflat‐marsh transition zone; (2) Elevation‐dependent spatial reconfiguration of marsh vegetation patches in response to the storm; (3) Different marsh response below and above an elevation threshold where a shift between marsh gain and marsh loss occurred. The observed landward decrease in storm‐induced marsh loss is attributed to a trade‐off between reduced disturbances due to landward increasing friction from the sediment bed and vegetation, and the landward increasing capacity of the vegetation to cope with disturbances. Our findings provide new insights relevant to the response of marsh systems to storms, and highlight the importance of the gradual and adequately wide sea‐to‐land gradient in delivering marsh resistance to extreme events. [ABSTRACT FROM AUTHOR]

A storm surge, classified as an extreme natural disaster, refers to unusual sea level fluctuations induced by severe atmospheric disturbances such as typhoons. Existing reanalysis data, such as ERA5, significantly underestimates the location and maximum wind speed of typhoons. Therefore, this study initially assesses the accuracy of tropical cyclone positions and peak wind speeds in the ERA5 reanalysis dataset. These results are compared against tropical cyclone parameters from the IBTrACS (International Best Track Archive for Climate Stewardship). The position deviation of tropical cyclones in ERA5 is mainly within the range of 10 to 60 km. While the correlation of maximum wind speed is significant, there is still considerable underestimation. A wind field reconstruction model, incorporating tropical cyclone characteristics and a distance correction factor, was employed. This model considers the effects of the surrounding environment during the movement of the tropical cyclone by introducing a decay coefficient. The reconstructed wind field significantly improved the representation of the typhoon eyewall and high-wind-speed regions, showing a closer match with wind speeds observed by the HY-2B scatterometer. Through simulations using the FVCOM (Finite Volume Community Ocean Model) storm surge model, the reconstructed wind field demonstrated higher accuracy in reproducing water level changes at Tanxu, Gaoqiao, and Zhangjiabang stations. During the typhoon's landfall in Shanghai, the area with the greatest water level increase was primarily located in the coastal waters of Pudong New Area, Shanghai, where the highest total water level reached 5.2 m and the storm surge reached 4 m. The methods and results of this study provide robust technical support and a valuable reference for further storm surge forecasting, marine disaster risk assessment, and coastal disaster prevention and mitigation efforts. [ABSTRACT FROM AUTHOR]

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The propagation and dissipation of typhoon-induced surface waves are vital to morphological evolution and related engineering within coastal and estuarine regions. An observation system was operated during Typhoon Higos, and TELEMAC--TOMAWAC numerical modeling was performed for Typhoons Hagupit, Hato, and Higos along the central coast of Guangdong and the Pearl River Estuary in China to explore variations in wave propagation and dissipation during typhoons. The results showed that wind waves were dominant before typhoon landfall, and the intense wind waves dissipated rapidly during typhoon decay, while they could stay longer within the estuarine regions. Landward wave propagation had a tendency to convert from being convergence-dominated to being dissipation-dominated with the morphological change and tended to converge at the mouth-bar region. Within the estuarine regions, waves dissipated more rapidly at the prismatic estuary than at the bell-shaped bays due to the limited width and rapid contraction of the outlet. Moreover, the track and scale of typhoons had critical effects on the generated wave field, and they dominated the intensity, propagation, and dissipation of the overall wave field. Specifically, typhoons with broader scales and longer moving tracks within the coastal regions of Guangdong Province enhanced the wind--wave interaction and induced a stronger and wider wave field, despite that their typhoon intensities were comparable (i.e., Hagupit vs. Hato). Furthermore, waves generated by compact and regular cyclone structures dissipated more strongly along the moving track of typhoons (i.e., Hato and Higos). Except for typhoons directly attacking the Pearl River Estuary, waves within the estuarine regions tended to dissipate/converge when located on the right/left side of the moving track of typhoons. [ABSTRACT FROM AUTHOR]

Atlantic tropical cyclones (TCs) are known to develop from African easterly waves (AEWs) that propagate across North Africa and out over the Atlantic Ocean. The relationship between AEWs and TCs has been the subject of numerous previous studies. There are, however, many Atlantic TCs that do not have AEW origins. In this study, we provide a novel analysis of the characteristics and trends of Atlantic TCs both with and without AEW origins using 43 years of observational and reanalysis data. To conduct this research, we identified TCs with and without AEW origins from the observational record between 1980 and 2022, and ran objective tracking algorithms on reanalysis data to identify the AEWs and TCs during this time period. We found statistically significant differences in the characteristics and environments of TCs with and without AEW origins. TCs with AEW origins are stronger and costlier, experience more favorable environmental conditions, and are more likely to make landfall in the Gulf of Mexico and the Caribbean when compared to TCs without AEW origins. Additionally, the 43‐year increasing trend in Atlantic TC activity is primarily driven by an increase in TCs with AEW origins that is associated with increasing AEW frequency and strength, with anthropogenic aerosols potentially driving this trend. In contrast, we found no trend in TCs without AEW origins. [ABSTRACT FROM AUTHOR]

The present study evaluated the performance of the Weather Research and Forecasting (WRF) model in the forecast of a very severe cyclonic storm (VSCS) Vardah that developed over the Bay of Bengal (BoB) and make landfall over the Tamil Nadu coast on 12 December 2016. The study examined the impact of microwave humidity sounder (MHS) satellite radiance data assimilation to forecast of structure, intensity and rainfall of Vardah cyclone near to the coast using two different land surface model (LSM; Noah and Noah-MP). The mean track error is about 33 and 38 km with data assimilation using Noah and Noah-MP LSM respectively and this error is about 41 km in without data assimilation using Noah and Noah-MP LSM. The predicted intensity of the storm in terms of the maximum surface wind is also slightly better predicted in data assimilation experiment with Noah LSM, this is due to the improved initial condition. Accumulated rainfall and the maximum reflectivity in terms of spatial distribution and magnitude of the VSCS Vardah is well simulated in all the experiments but slightly better in data assimilation experiments. Hovmoller diagram is also presented to see the shifting pattern of accumulated rainfall across the region during simulation period. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs) displace millions every year. While TCs pose hardships and threaten lives, their negative impacts can be reduced by anticipatory actions like evacuation and humanitarian aid coordination. In addition to weather forecasts, impact forecast enables more effective response by providing richer information on the numbers and locations of people at risk of displacement. We introduce a fully open-source implementation of a globally consistent and regionally calibrated TC-related displacement forecast at low computational costs, combining meteorological forecast with population exposure and respective vulnerability. We present a case study of TC Yasa which hit Fiji in December 2020. We emphasise the importance of considering the uncertainties associated with hazard, exposure, and vulnerability in a global uncertainty analysis, which reveals a considerable spread of possible outcomes. Additionally, we perform a sensitivity analysis on all recorded TC displacement events from 2017 to 2020 to understand how the forecast outcomes depend on these uncertain inputs. Our findings suggest that for longer forecast lead times, decision-making should focus more on meteorological uncertainty, while greater emphasis should be placed on the vulnerability of the local community shortly before TC landfall. Our open-source codes and implementations are readily transferable to other users, hazards, and impact types. This paper proposes an open-source, impact-based forecast for tropical cyclone population displacement using both cyclone forecasts and population settlements and vulnerabilities. This is applied to Tropical Cyclone Yasa, striking Fiji in 2020. [ABSTRACT FROM AUTHOR]

Post‐tropical cyclone Fiona made landfall in Nova Scotia, Canada, in September 2022 with the force of a Category 2 hurricane. Using 'risk society' as an analytical framework, and Thomas A. Birkland's 'focusing event' concept, this paper seeks to understand how publics construct risk in the context of climate change and how institutions engage with those narratives. A qualitative content analysis of 439 newspaper articles from across Canada reveals that most media provide a superficial description of hazard impacts. When media are critical, they connect Fiona to climate change, other extreme events, social vulnerability, and systemic inequality. In response to Fiona and industry trends, insurance representatives indicate a withdraw from covering low‐probability, high‐consequence events owing to ambiguity in risk analysis and financial interests, complicating hazard relief. Political actors' rhetoric is strong—delivering relief in unprecedented ways and offering new adaptive policy. However, a history of unfulfilled political promises to act on climate change elicits scepticism from media sources. [ABSTRACT FROM AUTHOR]

Numerous studies focus on the impacts of ENSO diversity on tropical cyclone (TC) activities in the western North Pacific (WNP). In recent years, there is a growing threat of landfalling and northward-moving TCs in East Asia, accompanying an increase in central Pacific (CP) El Niño. Here, we aim to discover variations in landfalling TCs during various types of CP El Niño (CP-I and CP-II El Niño). It is found that significant changes in landfalling and going northward TCs over East Asia north 20°N are modulated by CP-I El Niño. During CP-I El Niño, TCs tend to landfall more often over the mainland of China with longer duration, moving distance, and stronger power dissipation index (PDI) after landfall and increased TC-induced rainfall, due to favorable conditions (beneficial steering flow, weak vertical wind shear, increased specific humidity, increased soil moisture, and temperature), especially significant over the northeastern part. The situation over the mainland of China is reversed during eastern Pacific (EP) El Niño and CP-II El Niño, with a significant decrease in the characteristics with corresponding unfavorable environments. Over the Korean Peninsula and Japan, the frequency of TC landfalls, as well as the duration and the moving distance after landfall, exhibits greater levels during CP-I and CP-II El Niño than during EP El Niño due to favorable steering flow, and thus, TC-induced rainfall enhances correspondingly. Regarding the PDI over the Korean Peninsula and Japan, it remains relatively consistent across all El Niño types. However, a notable increase in the PDI during EP El Niño could be attributed to the higher intensity of TCs prior to landfall. [ABSTRACT FROM AUTHOR]

Prehistoric Polynesian voyaging into high latitudes with landfall in Antarctica remains a widely credited proposition. We examine it through archaeological and environmental evidence from the Subantarctic region of the southwest Pacific, focussing upon an extensive archaeological site at Sandy Bay on Enderby Island. Combining a new set of radiocarbon ages with former, older, ages we show that the site is now within the same rapid expansion phase in which South Polynesia was first colonised. Radiocarbon ages across the site indicate a single continuous settlement, probably of some decades. Consideration of limiting factors in Subantarctic settlement, including of seafaring capability and critical resources, suggests that the site was about as far south as prehistoric habitation could be sustained and was probably vacated at the onset of the Little Ice age (LIA) in the late 14th century. An absence of prehistoric remains on islands further south also suggests that Polynesian exploration reached a boundary 2000 km short of Antarctica. The southern case is discussed briefly in the wider context of Polynesian expansion. [ABSTRACT FROM AUTHOR]

Floods are consistently identified as the most serious global natural hazard, causing devastating loss of life and economic damage that runs into multiple billions of US dollars each year. At the coastline, many flood disasters are in fact compound flood events, with two or more flood drivers occurring concurrently or in quick succession. In coastal regions the combined effect of fluvial (river) and coastal (storm tides – storm surges and high astronomical tides) floods has a greater impact than if each occurred separately. Deltas in south-east Asia are particularly exposed to coastal compound floods as they are low-lying, densely populated regions subject to the intense rainfall storm surges frequently associated with tropical cyclone (TC) activity. For our study we used a sophisticated 1D river model, combined with 2D storm tide levels, to analyse past–present and future compound flood hazard and exposure for the Mekong River delta, one of the most flood-vulnerable deltas in the world. We found that with compound flooding, a greater area of the delta will be inundated, and some parts will flood to greater flood depth. Central areas around An Giang and the Dong Thap provinces are particularly impacted in our plausible scenario, where a TC makes landfall near the mouth of one Mekong River distributary. In the future delta, the impact of compound flooding is potentially more significant, as the same compound flood scenario inundates a greater area relative to the present case and to greater depth in many locations, and floods last longer. Compound flooding therefore has clear implications for flood managers of the future delta, who will need to ensure that existing and future flood defences are to the right standard and in the right locations to offer effective protection against this future risk. [ABSTRACT FROM AUTHOR]

Decisions on humanitarian responses to natural disasters are subject to considerable epistemic uncertainty. This paper advocates for postponing the decision point of pre-positioning relief supplies as close to landfall as possible and searching social media right post-landfall so that the demands can be estimated more accurately. We use a realistic hurricane preparedness case to demonstrate the effectiveness of our models and parametric estimation using social media data. The optimal timing to deploy relief supplies before hurricane landfall is noted to be 12 h in advance, which reduces the total cost by 13% more than if relief supplies are deployed 18+ hours in advance. Meanwhile, utilizing social media information can reduce the total cost as well as all kinds of specific costs being considered, excluding the point of dispensing (POD) sites setup cost, by approximately 15%. As the attitude toward risk goes from optimistic, to neutral, and to pessimistic, the number of PODs increases from 3 to 7, and to 8. A similar pattern can be noted in the total costs incurred by these decision-makers. Further, as the aversion to risk increases, locations tend to be chosen farther from landfall with these farther locations serving the less severe patients. [ABSTRACT FROM AUTHOR]

The Sundarbans is the world's largest contiguous mangrove forest with an area of about 10,000 square kilometers and shared between Bangladesh and India. This world-renowned mangrove forest, located on the lower Ganges floodplain and facing the Bay of Bengal, has long served as a crucial barrier, shielding southern coastal Bangladesh from cyclone hazards. However, the Sundarbans mangrove ecosystem is now increasingly threatened by climate-induced hazards, particularly tropical cyclones originating from the Indian Ocean. To assess the cyclone vulnerability of this unique ecosystem, using geospatial techniques, we analyzed the damage caused by past cyclones and the subsequent recovery across three salinity zones, i.e., Oligohaline, Mesohaline, and Polyhaline. Our study also examined the relationship between cyclone intensity with the extent of damage and forest recovery. The findings of our study indicate that the Polyhaline zone, the largest in terms of area and with the lowest elevation, suffered the most significant damage from cyclones in the Sundarbans region, likely due to its proximity to the most cyclone paths. A correlation analysis revealed that cyclone damage positively correlated with wind speed and negatively correlated with the distance of landfall from the center of the Sundarbans. With the expectation of more extreme weather events in the near future, the Sundarbans mangrove forest faces a potentially devastating outlook unless both natural protection processes and human interventions are undertaken to safeguard this critical ecosystem. [ABSTRACT FROM AUTHOR]

Tropical cyclones (TCs), often characterized by high wind speeds and heavy rainfall, cause widespread devastation, affecting millions of people and leading to economic losses worldwide. TC-specific research in Georgia is scarce, likely due to the minimal geographical extent of its coast and the infrequency of direct landfalls. Research on Georgia TCs does not account for storms that make landfall in other southeastern states (e.g., Florida) and continue north, northeast, or northwest into Georgia. This study used the North Atlantic Basin hurricane database (HURDAT2) to quantify the spatiotemporal patterns of direct and indirect landfalling of Georgia tropical cyclones (>16 ms−1) from 1851 to 2021. TC-induced rainfall was also quantified using rainfall data (nClimGrid-Daily and nClimGrid) from 1951 to 2021 to estimate the proportion of Georgia's total annual and monthly rainfall attributed to TCs. A multi-methodological approach, incorporating statistics and mapping, is employed to assess the trends of Georgia's tropical cyclones and the associated rainfall. The study analyzed 113 TCs and found that, on average, less than one TC annually ( x ¯ = 0.66) traverses the state. September averaged the highest percentage (25%) of TC-induced rainfall, followed by October (14%), and August (13%). This pattern aligns with the TC season, with the highest frequency of TCs occurring in September (n = 35), followed by August (n = 25), and October (n = 18). We found that 10% of tropical storms make landfall on the coastline, while the remaining 91% enter Georgia by making landfall in Florida (92%), Louisiana (7%), or South Carolina (1%) first. A threat of TCs during the peak of the season emphasizes the importance of heightened awareness, increased planning practices, and resource allocation during these periods to protect Georgia's history and natural beauty, and its residents. [ABSTRACT FROM AUTHOR]

In this study, the storm surge processes and characteristics of Tide-Surge Interactions (TSI) induced by the sequential tropical cyclones (TCs) BARIJAT and MANGKHUT (2018) in the Northern South China Sea (NSCS) are investigated using the numerical model. By comparing the impacts of the two TCs, we find that storm surges are significantly influenced by multiple factors. Notably, bays situated on the western side of the cyclone's landfall point exhibit a double peak pattern in storm surge. In addition, TSI exhibits a pronounced impact across bays affected by the two TCs, with amplitude fluctuations ranging from -0.3 to 0.3 meters and contributing approximately -5% to -20% to the peaks of storm surge. Comparative analysis of TSI variations reveals that tides act as the primary determinant, significantly influencing both the magnitude and period of TSI. Dynamic analysis further highlights that variations in TSI are dominated by barotropic pressure gradient and bottom friction stress. Moreover, TSI affects the frequency of storm surges, introducing high-frequency tidal signals to storm surges and reducing the frequency of storm surges. [ABSTRACT FROM AUTHOR]

Rainfall associated with landfalling tropical cyclones (TCs) along the Northern Vietnam coast is examined to develop an asymmetric parametric TC‐induced rainfall model starting from the axisymmetric Rain‐Climatology and Persistence (R‐CLIPER) model. We recalibrated the R‐CLIPER model (original R‐CLIPER denoted as NHC) against observed rainfall patterns of 14 landfalling TCs from 2001 to 2021 in the Northern Vietnam coast, while relaxing the model's underlying linear relationships. The recalibrated R‐CLIPER (denoted as Fit‐Ax), still axisymmetric, suggests that some parameters are better correlated with the normalized maximum wind speed using logarithmic and exponential relationships. Fit‐Ax reduces the 12‐hr total rainfall overall root‐mean‐square errors (RMSEs) and Bias magnitudes in the before‐ and after‐landfall periods from NHC for the entire 500‐km TC domain. We further redistribute the Fit‐Ax rainfall intensity across the four quadrants with respect to the TC forward motion to account for the observed large asymmetry in quadrant rainfall (version denoted as Fit‐As). The vertical wind shear (VWS) and landfall (before or after) are considered in this redistribution. Fit‐As generally outperforms Fit‐Ax and NHC in reproducing the observed rainfall distribution for the 14 TCs. At the quadrant level, both Fit‐Ax and Fit‐As show significant improvement in Bias over NHC. Fit‐As is further better overall in RMSE and Skill when weighted by quadrant rainfall volume. In pattern matching, Fit‐As produces the best grid‐averaged Pearson correlation coefficients for 11 TCs. In addition, its equitable threat scores (ETSs) are best beyond the 20‐mm rainfall threshold, with the maximum of 0.299 at the 90‐mm rainfall threshold. Thus, our locally fitted asymmetric rainfall model demonstrates improved capability in reproducing the historical TC‐induced rainfall along the Northern Vietnam coast. [ABSTRACT FROM AUTHOR]

Crisis response involves extensive planning and coordination within and across a multitude of agencies and organisations. This study explores how on‐the‐ground crisis response efforts align with crisis response guidelines. These guidelines are key to the effectiveness of crisis response. To this end, we construct, analyse and compare emergency response networks by using network analysis and natural language processing methods. Differences between plans and practice, that is, false positives (actions delivered but not prescribed) and false negatives (actions prescribed but not delivered), can impact response evaluation and policy revisions. We investigate collaboration networks at the federal, state and local level extracted from official documents (prescribed networks) and empirical data (observed networks) in the form of situational reports (n = 109) and tweets (n = 28,050) from responses to major hurricanes that made landfall in the United States. Our analyses reveal meaningful differences between prescribed and observed collaboration networks (mean node overlap ~9.94%, edge overlap ~3.94%). The observed networks most closely resemble federal‐level networks in terms of node and edge overlap, highlighting the prioritisation of federal response guidelines. We also observed a high ratio of false positives, that is, nongovernmental, nonprofit and volunteer organizations, that play a critical role in crisis response and are not mentioned in response plans. These findings enable us to evaluate the current best practices for response and inform emergency response policy planning. [ABSTRACT FROM AUTHOR]

El Niño-Southern Oscillation (ENSO) tropical cyclones (TCs) are important moisture sources in semiarid, mountainous Northwestern Mexico. Studies conducted in this region have not expressed differences between coastal and mountainous regions under different ENSO scenarios, instead, changes have been explored in the entire region as a whole. Attempting to fill this gap, the present study conducted an analysis of observed changes in rainfall contribution of landfalling tropical cyclones under five scenarios: (1) El Niño, (2) La Niña, (3) El Niño to La Niña, (4) La Niña to El Niño, and (5) Neutral on mountainous, foothill and coastal regions. In addition, the changes observed were explored under five scenarios in monthly precipitation peak and seasonal cumulative precipitation, which are important characteristics during the North American Monsoon (NAM). The results indicate that most changes occur in the coastal region during La Niña, El Niño to La Niña and Neutral scenarios, where more than half of the stations recorded average precipitation above their regional climatology. Thus, six TCs made landfall with an average of 73% of stations that recorded accumulations above their regional climatology (i.e. NAM precipitation) mainly affecting the southern foothill region. Although the observed changes do not show a well-defined seasonal pattern distinguishing the three regions, changes may be identified and explained by the latitudinal gradient, relief and soil moisture characteristics strongly influenced by local factors. Unfortunately, these results make it difficult to forecast the precipitation response under the different scenarios. [ABSTRACT FROM AUTHOR]

Simple Summary: Low-pressure systems frequently occur during the summer in coastal areas and can be detrimental to commercial poultry houses. The effects of air temperature and humidity vary across different periods. Throughout the generation of low-pressure systems, landfall, and disappearance, air temperature and humidity changes can interfere with the housing environment. However, farmers often overlook the impact of low-pressure systems on large-scale poultry houses, which may impair the production of laying hens. This study investigated the effects of the different low-pressure systems on the housing environment and egg production in large-scale poultry houses in China. The results indicated that a single low-pressure system reduced the laying performance, whereas a sustained low-pressure system mitigated the impact on egg production. This study aimed to determine the effect of low-pressure systems on the environment and the laying performance of large-scale poultry houses during the summer and to provide a basis for farmers to adjust their environmental control strategies under extreme weather conditions. Low-pressure systems (LPSs) are among the most critical weather systems, producing excessive precipitation that causes air temperatures to drop and rise considerably. Acute temperature changes directly affect poultry feed intake (FI) and laying performance. To explore the effects of LPSs on hens, the parameters of air temperature, relative humidity, egg production, and feed utilization efficiency were evaluated during different LPSs in three houses. Results indicated that about 2.8 ± 0.7 d, 2.4 ± 0.5 d, and 2.4 ± 0.5 d before the LPS landfall in houses 1, 2, and 3, respectively, the indoor air temperature started to decrease, with the average decreases being 1.7 °C ± 0.4 °C, 2.4 °C ± 0.6 °C, and 1.8 °C ± 0.4 °C, respectively. Significant differences were observed between different LPSs for reducing indoor air temperature (p < 0.05) in the three houses. In house 1, the egg production rates (EPRs) were decreased by 6.6% and 1.1% when LPSs 1 and 2 landed. The average egg weight (AEW) and FI during the LPS landfall were significantly higher than those before the LPS landfall (p < 0.01). Under successive LPSs landfall in the three houses, the EPRs initially reduced by 3.9%, 4.0%, and 0.5%, respectively, but the second LPS event increased the EPRs by 1.8%, 5.3%, and 1.0%, respectively. Furthermore, the LPS landfall increased the feed conversion ratio (FCRe) in the three houses, all above 2.00. In conclusion, LPSs can reduce heat stress, lower the EPRs, and lead to higher FI, FCRe, and AEW. [ABSTRACT FROM AUTHOR]

Previous research has shown that people use a benchmark hurricane as part of their preparation and evacuation decision-making process. While hurricanes are a common occurrence along the Gulf Coast, research on personal memories of past storms is lacking. Particularly, how well do people remember the track and geophysical hazards (wind speed, storm surge, and total rainfall) of past storms? The accurate or inaccurate recollection and perception of previous storm details can influence personal responses to future storms, such as the decision to evacuate or take other life-saving actions. Survey responses of residents in Alabama and Mississippi were studied to determine if people were accurately able to recall a notable storm's name when seeing an image of the storm's track. Those who were able to identify the storm by its track were also asked if they could remember the storm's maximum reported rainfall, maximum sustained winds, and storm surge at landfall. Results showed that there were statistically significant differences between the levels of accurate recall for different storms, with Hurricanes Katrina and Michael having the most correct responses. Regardless of the storm, most people struggled to remember geophysical hazards. The results of this study are important as they can inform broadcast meteorologists and emergency managers on forecast elements of the storm to better emphasize in future communication in comparison to the actual values from historical benchmark storms. [ABSTRACT FROM AUTHOR]

A standalone Advanced Circulation (ADCIRC) model for the east coast of India with a high-resolution grid of 100 m near the coast is used to evaluate coastal inundation resulting from the storm tides generated by recent cyclones. A directional surface roughness parametrization that alters wind speed and Manning's n friction coefficient to compute bottom friction based on land use/land cover (LULC) at a particular location is incorporated in the model. ERA5 reanalysis winds highlight that the cyclonic winds over the land are less intensive than nearby coastal oceans, particularly during landfall time, by approximately 29%–50%. Experiments are also designed to quantify the impact of surface and bottom friction on wind speed and the inward propagation of storm tides. A comparison of cyclonic wind speed after incorporating LULC data in the model is made with an automatic surface observation system (ASOS). It suggests a 15%–29% reduction, consistent with ASOS. The inundated area computed for the cyclones advocates a significant reduction (15%–50%) due to LULC. Sensitivity experiments with LULC are performed to examine the impact of mangroves in the Krishna estuary located in between two concave-shaped coastal geometries. Replacing wetlands with Mangroves results in a simultaneous decline in wind speed (12.5%) and inundated area (13.4%). It also highlights that bottom friction contributes (9.4%) in the inundated area against surface friction (4%). This study infers that further investigation and planning are mandatory to ensure coastal mangrove restoration initiatives and effective coastal management practices. [ABSTRACT FROM AUTHOR]

Observations and climate projections suggest a larger increase in tropical cyclone (TC)‐induced rainfall than that can be explained by the Clausius‐Clapeyron relationship of 7% increase in vapor content for each 1°C degree rise in temperature. However, these studies using diverse data sources and methods over various periods show inconsistencies regarding the location of this increase ‐ whether in the TC inner core or outer regions ‐ and offer differing explanations for the reported trends. This study uses the Pseudo‐global warming methodology on simulations of 117 western North Pacific TCs making landfall in Southeast Asia to investigate changes in TC rainfall structure by the end of the century under the SSP2‐4.5 and SSP3‐7.0 scenarios. Specifically, it tests the sensitivity of changing trends to various analysis methods used in previous studies and identifies the underlying physical mechanisms driving these changes. The findings indicate an amplified increase in rainfall in the TC inner core across all future scenarios, along with potentially decreased rainfall in the outer region under certain future climate conditions. Among TC categories, Supertyphoons exhibit the most significant increased rainfall across future states. Changes in TC primary and secondary circulations, TC structure, and the convergence of heat and moisture are the main factors shaping future rainfall patterns, outweighing the effects of changes in atmospheric and convective stability. Plain Language Summary: Tropical cyclone (TC)‐related rainfall is increasing with global warming. Typically, a 1°C increase in temperature leads to about a 7% increase in the atmosphere's water vapor holding capacity. However, the rise in TC rainfall outpaces this rate. Observations indicate this enhanced increase occurs in the TC outer region due to greater environmental moisture. Contrarily, modeling future projections suggest this concentrates in the inner core due to intensified TCs. This study analyzes a large data set of 819 simulations from 117 TCs making landfall in Southeast Asia to capture changes in future rainfall patterns under two contemporary climate change scenarios. Our findings reveal that the enhanced increase occurs in the TC inner core in all future states, while rainfall in the outer region decreases under specific climate conditions. Supertyphoons generate the heaviest rainfall, with minimal variations observed across climate scenarios. Variations of all dynamic and thermodynamic factors closely tied to TC rainfall are investigated to provide a comprehensive picture of the physics behind the changes. The interplay between TC dynamics (e.g., primary and secondary circulations), TC structure, and thermodynamic conditions (e.g., convergence of moisture, and temperatures), plays a critical role in the changing behaviors of TC rainfall. Key Points: Rainfall increases in the cyclone's inner core across all future states but decreases in the outer region under specific statesVariations in cyclone circulations, structure, convergence of moisture and heat in future climates drive rainfall changing patternsSupertyphoons cause the heaviest rainfall compared to other categories, with slight variations noted across climate conditions [ABSTRACT FROM AUTHOR]

Among the set of phenological traits featuring mangrove ecosystems, litterfall production stands out with marked intra-annual and longer-term variation. Furthermore, mangrove forests resilience is one of the most important ecological attribute, reconciling the juxtaposed terrestrial and marine environment such transitional systems occupy. However, world's mangroves are nowadays facing recurrent climatic events, reflected in anomalies depicted by major drivers, including temperature and precipitation. This physical-environmental setting may either constrain or favor overall forest productivity. A combination of time series analysis (spectral density and cross-correlation techniques) and statistical model fitting (General additive model) was implemented to explore trends in total litterfall of a well-developed mangrove forest in southeastern Gulf of Mexico (Celestun Lagoon, SE Mexico) and potential association with the varying behavior of temperature (°C) and precipitation (mm month-1), highlighting their anomalies. The results are consistent with a synchronous response between litterfall production and climatic variables (mean monthly temperature and total monthly precipitation). Concurrent peak litterfall production in Celestun lagoon with high temperatures and precipitation occurred during June and October, featuring a two-month time lag for the response time. More than half of the litterfall anomalies (53.5%) could be reflecting either multiple sources of climatic anomalies (maximum, minimum, and monthly average temperature and monthly total precipitation) or single point events (cyclone landfall). This relationship dynamics showed an interannual persistence (1999–2010). The structure portrayed by the litterfall time-series was not unequivocally related to climatic anomalies. Arguably, climatic anomalies behave with different intensities and even may exhibit complex interactions among them. The study of anomalies provides a baseline for a better grasp of: i) mangrove anomalies responses and ii) their vulnerability to these extremes. [ABSTRACT FROM AUTHOR]

Hurricane Harvey was the second costliest storm to impact the U.S. More research is needed to understand the mental health consequences of these extreme events in children and adolescents extending beyond the acute recovery period. Daily anonymized Crisis Text Line (CTL) conversations were used to understand patterns in crisis responses for youth one year before and after Harvey's landfall. A quasi-experimental difference-in-differences analysis compared changes in texts for stress/anxiety, depression, thoughts of suicide, and self-harm following Harvey between exposed and unexposed youth in Texas. CTL users with Texas-based area codes (N = 23,016) were compriesd largely of youth who self-identified as female (78.1 %), 14–17 year old (50.4 %), white (38.9 %), and LGBTQ+ (51.2 %). We observed parallel increases in crisis texts for depression and thoughts of suicide in most months following Harvey among exposed and unexposed youth. However, non-impacted youth had significantly larger increases in texts for depression up to three months post-Harvey and thoughts of suicide one year after Harvey compared to directly impacted communities. Sample size was restricted to texters who completed the post-conversation demographics survey, who may fundamentally differ from those who declined to respond. Harvey exposure was determined using texter area code and county-level disaster declarations, limiting our ability to guarantee individual-level exposure. Texas youth traditionally considered unexposed experienced nearly identical increases in concerns of depression and thoughts of suicide to those directly exposed. Findings suggest spillover effects (e.g., economic concerns, media exposure) may contribute to statewide impacts on youth mental health after natural disasters. • More research on mental health impacts of climate disasters in youth is needed. • Causal difference-in-difference model measured crisis response in youth post-Harvey. • Depression and thoughts of suicide increased statewide in Texas youth after Harvey. • Findings suggest need for broader dissemination of crisis support services in youth. [ABSTRACT FROM AUTHOR]

Zonal extensions of the Western Pacific subtropical high (WPSH) strongly modulate extreme rainfall activity and tropical cyclone (TC) landfall over the Western North Pacific (WNP) region. These zonal extensions are primarily forced on seasonal timescales by inter‐basin zonal sea surface temperature (SST) gradients. However, despite the presence of large‐scale zonal SST gradients, the WPSH response to SSTs varies from year to year. In this study, we force the atmosphere‐only NCAR Community Earth System Model version 2 simulations with two real‐world SST patterns, both featuring the large‐scale zonal SST gradient characteristic of decaying El Niño‐developing La Niña summers. For each of these patterns, we performed four experimental sets that tested the relative contributions of the tropical Indian Ocean, Pacific, and Atlantic basin SSTs to simulated westward extensions over the WNP during June–August. Our results indicate that the subtle differences between the two SST anomaly patterns belie two different mechanisms forcing the WPSH's westward extensions. In one SST anomaly pattern, extratropical North Pacific SST forcing suppresses the tropical Pacific zonal SST gradient forcing, resulting in tropical Atlantic and Indian Ocean SSTs being the dominant driver. The second SST anomaly pattern drives a similar westward extension as the first pattern, but the underlying SST gradient driving the WPSH points to intra‐basin forcing mechanisms originating in the Pacific. The results of this study have implications for understanding and predicting the impact of the WPSH's zonal variability on tropical cyclones and extreme rainfall over the WNP. Plain Language Summary: Westward extensions of the Western North Pacific subtropical high (WPSH) drive rainfall extremes over the Western North Pacific basin, and is important for the prediction of summer rainfall, including monsoonal rainfall and tropical cyclone activity. Studies have previously highlighted the importance of tropical large‐scale zonal sea surface temperature (SST) gradient—warm tropical Indian Ocean in conjunction with cold equatorial eastern Pacific Ocean—in developing and maintaining the summer WPSH and westward extensions. Here, we further show that even with very similar SST patterns, the large‐scale zonal SST pattern may belie forcing from inter‐basin SSTs versus intra‐basin SSTs. We find that the net influence from the Pacific basin determines whether inter‐basin remote SST gradients versus intra‐basin Pacific SST gradients are the predominant driver of westward extensions. Key Points: Two similar SST patterns belie two different mechanisms forcing the subtropical high's westward extensionsTropical Pacific SST gradient forcing of westward extensions can be suppressed by its extratropical SST forcingRemote Atlantic SST forcing drives westward extensions when the local net Pacific forcing is weak [ABSTRACT FROM AUTHOR]