Assimilation of aircraft observations over the Indian monsoon region: Investigation of the effects of COVID-19 on a reanalysis

Since March 2020, the COVID-19 pandemic has significantly reduced the availability of global aircraft-based observations (ABOs), which has been restored later in 2021. This study focuses on the impact of ABOs on a regional reanalysis. Indian Monsoon Data Assimilation and Analysis (IMDAA) is a regional reanalysis for a period from 1979 to 2020 (originally up to 2018) over India and surrounding regions produced at the National Centre for Medium Range Weather Forecasting (NCMRWF), India, in collaboration with the UK Met Office. A comparison of the impact of ABOs on other conventional and satellite observations assimilated in the NCMRWF global model and IMDAA during 2019 and 2020 revealed the importance of ABOs, particularly in IMDAA, since it did not assimilate the latest satellite data as the IMDAA system was frozen in October 2016. A data denial experiment that removes all the ABOs from the IMDAA assimilation system for a period from March to November 2019 is designed. The results from the IMDAA reanalysis run, which assimilates ABOs during the same period, are compared with the data denial experiment. Assimilation of ABOs strengthened the upper tropospheric circulation, the Tropical Easterly Jet (TEJ), during the Indian summer monsoon compared to the data denial experiment. Analysis of the features of two cyclones that developed over the North Indian Ocean during the study period revealed that ABO assimilation played a key role in simulating the track and intensity of these cyclones when they were in the ‘severe' category. Since the sample is small, more cyclone cases need to be analysed to consolidate the result. © 2023 Royal Meteorological Society.

Cyclone Harold and the role of traditional knowledge in fostering resilience in Vanuatu

This article examines the role of traditional knowledge, skills, and values in fostering resilience in Vanuatu, the world's most at-risk country from natural hazards. We study responses to severe Tropical Cyclone (TC) Harold, which devastated the nation's northern islands in April 2020 just as a state of emergency had been declared in response to COVID-19. This necessitated severe restrictions on the delivery of relief supplies and a ban on the arrival of overseas humanitarian workers, forcing remote communities to adopt local responses to the emergency and cope with food insecurity through traditional resilience strategies and values that promote resource-sharing and cooperation. We use a mixed methods approach to analyse the content, extent, and transmission of traditional knowledge in Vanuatu and link this to evidence of its usefulness during TC Harold. Quantitative data from field surveys with two groups of respondents are combined with reports on responses to TC Harold both nationally and along the remote western coast of Santo Island. We also review the extent of traditional knowledge in current educational curricula in Vanuatu. Results illustrate how traditional ecological knowledge and social capital played a key role in disaster response and recovery, but such knowledge is mainly held by older people, and its use by younger generations is declining. We conclude that with rising global temperatures predicted to generate more extreme weather events, and external funds for disaster relief likely to decline, there is a need to build greater adaptive capacity at the local level through the revival of centuries-old informal transmission pathways of knowledge and values. (PsycInfo Database Record (c) 2022 APA, all rights reserved)

iStage: a deep learning based framework to determine the stage of disaster management cycle from a social media message

Purpose: This study aims to propose iStage, i.e. an intelligent hybrid deep learning (DL)-based framework to determine the stage of the disaster to make the right decisions at the right time. Design/methodology/approach: iStage acquires data from the Twitter platform and identifies the social media message as pre, during, post-disaster or irrelevant. To demonstrate the effectiveness of iStage, it is applied on cyclonic and COVID-19 disasters. The considered disaster data sets are cyclone Fani, cyclone Titli, cyclone Amphan, cyclone Nisarga and COVID-19. Findings: The experimental results demonstrate that the iStage outperforms Long Short-Term Memory Network and Convolutional Neural Network models. The proposed approach returns the best possible solution among existing research studies considering different evaluation metrics – accuracy, precision, recall, f-score, the area under receiver operating characteristic curve and the area under precision-recall curve. Originality/value: iStage is built using the hybrid architecture of DL models. It is effective in decision-making. The research study helps coordinate disaster activities in a more targeted and timely manner. © 2023, Emerald Publishing Limited.

iRelevancy: a framework to identify the relevancy of a social media message to a disaster

Purpose: This study aims to propose a novel deep learning (DL)-based framework, iRelevancy, for identifying the disaster relevancy of a social media (SM) message. Design/methodology/approach: It is worth mentioning that a fusion-based DL model is introduced to objectively identify the relevancy of a SM message to the disaster. The proposed system is evaluated with cyclone Fani data and compared with state-of-the-art DL models and the recent relevant studies. The performance of the experiments is assessed by the accuracy, precision, recall, f1-score, area under receiver operating curve and precision–recall curve score. Findings: The iRelevancy leads to a better performance in accuracy, precision, recall, F-score, the area under receiver operating characteristic and area under precision-recall curve, compared to other state-of-the-art methods in the literature. Originality/value: The predictive performance of the proposed model is illustrated with experimental results on cyclone Fani data, along with misclassifications. Further, to analyze the performance of the iRelevancy, the results on other cyclonic disasters, i.e. cyclone Titli, cyclone Amphan and cyclone Nisarga are presented. In addition, the framework is implemented on catastrophic events of different natures, i.e. COVID-19. The research study can assist disaster managers in effectively maneuvering disasters during distress. © 2023, Emerald Publishing Limited.

Evacuation dilemmas of coastal households during cyclone Amphan and amidst the COVID-19 pandemic: a study of the Southwestern region of Bangladesh.

Cyclone Amphan battered the coastal communities in the southwestern part of Bangladesh in 2020 during the COVID-19 pandemic. These coastal communities were experiencing such a situation for the first time and faced the dilemma of whether to stay at home and embrace the cyclone or be exposed to the COVID-19 virus in the cyclone shelters by evacuating. This article intends to explore individuals' decisions regarding whether to evacuate in response to cyclone Amphan and in light of the risks of the COVID-19 pandemic. Consequently, this study investigated evacuation behaviors among the households and explored the impacts of COVID-19 during the evacuation procedures. We conducted household surveys to collect primary information and undertook 378 samples for interviews at a precision level of 0.05 in fourteen villages. Despite the utmost effort of the government, the results demonstrated that 96.6% of people in the coastal area received a cyclone evacuation order before the cyclone's landfall, and only 42% of people followed the evacuation order. The majority of households chose to stay at home because of fear of COVID-19 exposure in the crowded shelters. Although half of the evacuees were housed in cyclone shelters, COVID-19 preventive measures were apparently not set in place. Thus, this study will assist in crafting future government policies to enhance disaster evacuation plans by providing insights from the pandemic that can inform disaster management plans in the Global South.

SARS-CoV-2: a systematic review of indoor air sampling for virus detection.

In a post-pandemic scenario, indoor air monitoring may be required seeking to safeguard public health, and therefore well-defined methods, protocols, and equipment play an important role. Considering the COVID-19 pandemic, this manuscript presents a literature review on indoor air sampling methods to detect viruses, especially SARS-CoV-2. The review was conducted using the following online databases: Web of Science, Science Direct, and PubMed, and the Boolean operators "AND" and "OR" to combine the following keywords: air sampler, coronavirus, COVID-19, indoor, and SARS-CoV-2. This review included 25 published papers reporting sampling and detection methods for SARS-CoV-2 in indoor environments. Most of the papers focused on sampling and analysis of viruses in aerosols present in contaminated areas and potential transmission to adjacent areas. Negative results were found in 10 studies, while 15 papers showed positive results in at least one sample. Overall, papers report several sampling devices and methods for SARS-CoV-2 detection, using different approaches for distance, height from the floor, flow rates, and sampled air volumes. Regarding the efficacy of each mechanism as measured by the percentage of investigations with positive samples, the literature review indicates that solid impactors are more effective than liquid impactors, or filters, and the combination of various methods may be recommended. As a final remark, determining the sampling method is not a trivial task, as the samplers and the environment influence the presence and viability of viruses in the samples, and thus a case-by-case assessment is required for the selection of sampling systems.

Cyclone Harold and the role of traditional knowledge in fostering resilience in Vanuatu

This article examines the role of traditional knowledge, skills, and values in fostering resilience in Vanuatu, the world’s most at-risk country from natural hazards. We study responses to severe Tropical Cyclone (TC) Harold, which devastated the nation’s northern islands in April 2020 just as a state of emergency had been declared in response to COVID-19. This necessitated severe restrictions on the delivery of relief supplies and a ban on the arrival of overseas humanitarian workers, forcing remote communities to adopt local responses to the emergency and cope with food insecurity through traditional resilience strategies and values that promote resource-sharing and cooperation. We use a mixed methods approach to analyse the content, extent, and transmission of traditional knowledge in Vanuatu and link this to evidence of its usefulness during TC Harold. Quantitative data from field surveys with two groups of respondents are combined with reports on responses to TC Harold both nationally and along the remote western coast of Santo Island. We also review the extent of traditional knowledge in current educational curricula in Vanuatu. Results illustrate how traditional ecological knowledge and social capital played a key role in disaster response and recovery, but such knowledge is mainly held by older people, and its use by younger generations is declining. We conclude that with rising global temperatures predicted to generate more extreme weather events, and external funds for disaster relief likely to decline, there is a need to build greater adaptive capacity at the local level through the revival of centuries-old informal transmission pathways of knowledge and values © The Author(s) 2022. (Copyright notice)

Risk Governance Perspectives for compounding hazards: a case study in Megacity Kolkata

The Kolkata Megacity is vulnerable to several hazards ranging from weather related to biological: tidal upsurge, earthquake, cyclone, urban storm/heavy rain-induced flooding and waterlogging, and others. The Kolkata Metropolitan Area is a continuous stretch of the urban and peri-urban area along with the east and west coast of the Hooghly River, which is surrounded by some rural regions acting as a green belt as protecting cover of the city. Cyclone Amphan on May 2020 made landfall and wreaked havoc when the world was already reeling under the COVID-19 pandemic. The twin disasters—hydrometeorological and biological hazard compounded—and the cascading impacts have affected a significant population on West Bengal. Present study explores the risk governance perspectives in the context of dual disasters. The study also reflects the need of risk informed community preparedness for immediate response and early recovery as the key element for the resilience building. © 2022 Elsevier Inc. All rights reserved.

Hydrometeorological disasters during COVID-19: Insights from topic modeling of global aid reports.

Since the beginning of the COVID-19 pandemic, the world has experienced numerous hydrometeorological disasters along with it. The pandemic has made disaster relief work more challenging for humanitarian organizations and governments. This study aims to provide an overview of the topics/issues of concern in the countries while responding to hydrometeorological extreme events (e.g., floods and cyclones) during the pandemic. Latent Dirichlet Allocation (LDA), a computational topic modeling technique, is employed to reduce the numerous (i.e., 1771) humanitarian reports/news to key terms and meaningful topics for 24 countries. Several insights are derived from the LDA results. It is identified that countries have suffered multiple crises (such as locust attacks, epidemics and conflicts) during the pandemic. Maintaining social distancing while disaster evacuation and circumventing the lockdown for relief work have been difficult. Children are an important topic for most countries; however, other vulnerable groups such as women and the disabled also need to be focused upon. Hygiene is not a highly weighted topic, which is of concern during a pandemic that mandates good sanitation to control it effectively. However, health is of great importance for almost all countries. The novelty of the paper lies in its interdisciplinary approach (usage of a computational technique in disaster management studies) and the timely examination of disaster management experiences during the ongoing pandemic. The insights presented in the study may be helpful for researchers and policy-makers to initiate further bottom-up work to address the challenges in responding to hydrometeorological disasters during a pandemic.

Environmental Effects on Viable Virus Transport and Resuspension in Ventilation Airflow.

To understand how SARS-CoV-2 spreads indoors, in this study bovine coronavirus was aerosolized as simulant into a plexiglass chamber with coupons of metal, wood and plastic surfaces. After aerosolization, chamber and coupon surfaces were swiped to quantify the virus concentrations using quantitative polymerase chain reaction (qPCR). Bio-layer interferometry showed stronger virus association on plastic and metal surfaces, however, higher dissociation from wood in 80% relative humidity. Virus aerosols were collected with the 100 L/min wetted wall cyclone and the 50 L/min MD8 air sampler and quantitated by qPCR. To monitor the effect of the ventilation on the virus movement, PRD1 bacteriophages as virus simulants were disseminated in a ¾ scale air-conditioned hospital test room with twelve PM2.5 samplers at 15 L/min. Higher virus concentrations were detected above the patient's head and near the foot of the bed with the air inlet on the ceiling above, exhaust bottom left on the wall. Based on room layout, air measurements and bioaerosol collections computational flow models were created to visualize the movement of the virus in the room airflow. The addition of air curtain at the door minimized virus concentration while having the inlet and exhaust on the ceiling decreased overall aerosol concentration. Controlled laboratory experiments were conducted in a plexiglass chamber to gain more insight into the fundamental behavior of aerosolized SARS-CoV-2 and understand its fate and transport in the ambient environment of the hospital room.

Vehicular Relaxation And Amphan Cyclone: Is It A Double Threat To India Towards Combat Of COVID-19

The COVID-19 spread as a pandemic and more than 185 countries have suffered from it. Various strategies have been devised to combat the virus and prevent it from spreading. In India, lockdown had been initiated since 24th March 2020 and social gatherings had been restricted. But due to the slump in the economy and to boost up trade, certain manufacturing sectors have been opened and vehicular movement was relaxed. PM2.5 and NO2 levels started to rise drastically, which were initially reduced during the lockdown. Moreover, the recent Amphan super cyclonic storm may have increased the risk of COVID spread. A statistical Spearman correlation analysis of the air quality index (AQI) parameters with meteorological variables was carried out to ascertain the significance. Detailed epidemiological studies are warranted to confirm the spike in COVID positive cases may have been related to unforeseen torrential rains as a result of Amphan the cyclone and increased vehicular pollution. © 2021 - Kalpana Corporation

A Robot Assisted High-flow Portable Cyclone Sampler for Bacterial and SARS-CoV-2 Aerosols

Airborne transmission of infectious diseases attracts great attention since the COVID-19 pandemic. Yet, there has been an intense dispute about aerosol transmission of the disease, which is largely due to lack of qualified instruments for studying the subject. Air sampling plays a critical role in all air pollution related study, and particularly critical for airborne pathogen detection. Here, we designed and evaluated a portable and high volume (400 L min-1) cyclone sampler named as Yao-CSpler using aerosolized Polystyrene (PS) uniform microspheres, Bacillus subtilis var. niger, Pseudomonas fluorescens, and both indoor and outdoor air particles. The experimental cutoff size of the Yao-CSpler was demonstrated to be 0.58 m (while the calculated theoretical value is 1.84 m), and the sampler has shown stable microbial collection performances for bacteria, fungi, and even viruses. The sampler had a physical collection efficiency of close 100% for particles of larger than 1 m. Jet-to-liquid distance and sampling duration were shown to substantially influence the sampler performance. Given the same sampling duration, the performances of the Yao-CSpler were significantly higher than those of the traditional BioSampler (SKC Inc.) in terms of samples' bacterial diversity. The developed sampler coupled with a robot has been successfully applied to sampling airborne SARS-CoV-2 in both Wuhan and Beijing during the COVID-19 outbreaks. With a high sampling flow, the Yao-CSpler was shown to be able to collect the SARS-CoV-2 with a detectable concentration level down to 9-219 viruses m-3 in clinical settings housing COVID-19 patients. Further more efficient bioaerosol sampler, which is able to rapidly capture low level pathogenic agents, is urgently required to better understand and confront airborne transmission of infectious diseases.

From the Cyclone Idai disaster to the COVID-19 pandemic: An account of inadvertent social capital enhancement in Eastern Chimanimani, Zimbabwe.

Zimbabwe suffered a devastating meteorological disaster when Cyclone Idai affected the southeast part of the country in March 2019. Barely a year after the cyclonic event, the coronavirus disease 2019 (COVID-19) pandemic emerged, leading to the declaration of a nationwide lockdown that paralysed socio-economic systems. This article examines how social capital was autonomously cultivated and eventually utilised by the Cyclone Idai disaster survivors in Eastern Chimanimani to face the fresh socio-economic challenges of the COVID-19 pandemic. In this article, a qualitative method embedded in a case study design was used. Data was collected using 30 purposively selected key respondents who interacted with victim communities from March to July 2020. A thematic content analysis approach was applied to obtain opinion patterns and subsequent inferences. The study results revealed a lack of immediate external disaster intervention during the Cyclone Idai disaster in Chimanimani. Accordingly, a strong sense of collective action developed between victim communities, thus enabling them to perform hasty operations meant to salvage lives and property. The enhanced social capital helped the Cyclone Idai victims to face the new COVID-19 lockdown challenges. This article recommends pro-active and well-coordinated government and private sector disaster response strategies supporting local area initiatives to minimise loss of lives and property during disaster situations.

High-volume sampler for size-selective sampling of bioaerosols including viruses.

Owing to the recent global spread of the new coronavirus SARS-CoV-2, the development of technology to effectively detect viruses in crowded public places is urgently needed. In this study, a three-stage high-volume bioaerosol sampler was developed for the size-selective sampling of bioaerosols through the suction of air at a high flow rate of 1000 L/min. In stage 1, an omnidirectional inlet cyclone separator that can draw air from all directions was applied to collect bioaerosols larger than 10 µm in the collection fluid. In stage 2, an axial flow cyclone separator was used to collect bioaerosols sized between 2.5 and 10 µm in the collection fluid. In stage 3, bioaerosols smaller than 2.5 µm were collected on a filter and extracted in a solution through an elution process using a sodium phosphate buffer. To simulate the suspension of bioparticles including viruses that are attached to other particles in the atmosphere, the aerosol samples were prepared by coagulating aerosolized bacteriophages with Arizona test dust. Then, the coagulated particles were collected for 30 min using the developed bioaerosol sampler, and the samples collected in each stage were analyzed via polymerase chain reaction (PCR) method. The PCR analysis results confirmed that the high-volume bioaerosol sampler enables size-selective bioaerosol sampling even at a high airflow rate of 1000 L/min. The developed high-volume bioaerosol sampler will be useful in detecting viruses through PCR analysis because it can collect bioaerosols within a specific size range.

Understanding the nexus between public risk perception of COVID-19 and evacuation behavior during cyclone Amphan in Bangladesh.

In May 2020, when Bangladesh was struggling with community transmission of COVID-19, the country had to face the strongest tropical storm- Cyclone Amphan -which puts the evacuation process in jeopardy. Thus, it is crucial to measure the public risk perception about COVID-19 and its influence on the evacuation decision. This study explores the nexus between COVID-19 risk perception and coastal peoples' evacuation decisions during cyclone Amphan. With an analysis of 378 sample households survey data of the Satkhira district, this study developed the COVID-19 risk perception index using Principal Component Analysis (PCA) and categorized the respondents based on the score. The result shows that 1.85 %, 21.43 %, 45.77 %, 25.13 %, and 5.82 % have very low, low, moderate, high, and very high-risk perceptions, respectively. The analysis also reveals that 96.6 % of the respondents received an evacuation order during Amphan, but only 42 % complied with the order. The t-test analysis and common language effect size test of the survey data reveal that the respondents with a high perception score are 65 % less likely to evacuate than the respondents with low perception scores. This study has important implications in guiding concerned authorities to combat natural disasters during COVID-19 and other similar public health emergencies in the future.

Bioaerosol monitoring by integrating DC impedance microfluidic cytometer with wet-cyclone air sampler.

The recent outbreak of COVID-19 has highlighted the seriousness of airborne diseases and the need for a proper pathogen detection system. Compared to the ample amount of research on biological detection, work on integrated devices for air monitoring is rare. In this work, we integrated a wet-cyclone air sampler and a DC impedance microfluidic cytometer to build a cyclone-cytometer integrated air monitor (CCAM). The wet-cyclone air sampler sucks the air and concentrates the bioaerosols into 10 mL of aqueous solvent. After 5 min of air sampling, the bioaerosol-containing solution was conveyed to the microfluidic cytometer for detection. The device was tested with aerosolized microbeads, dust, and Escherichia coli (E. coli). CCAM is shown to differentiate particles from 0.96 to 2.95 µm with high accuracy. The wet cyclone air-sampler showed a 28.04% sampling efficiency, and the DC impedance cytometer showed 87.68% detection efficiency, giving a total of 24.59% overall CCAM efficiency. After validation of the device performance, CCAM was used to detect bacterial aerosols and their viability without any separate pretreatment step. Differentiation of dust, live E. coli, and dead E. coli was successfully performed by the addition of BacLight bacterial viability reagent in the sampling solvent. The usage could be further extended to detection of specific species with proper antibody fluorescent label. A promising strategy for aerosol detection is proposed through the constructive integration of a DC impedance microfluidic cytometer and a wet-cyclone air sampler.

Influence of Super Cyclone "Amphan" in the Indian Subcontinent amid COVID-19 Pandemic.

Tropical cyclone "Amphan" developed as a super cyclone on 19 May 2020 and caused severe impact on the landmass with very high torrential precipitation (>250 mm day-1), and extremely high wind speed (>150 km h-1) after landfall on 20 May 2020. The tropical cyclone Amphan largely affected agricultural land (78.2%) and forest, including mangroves (10.8%) in eastern India and Bangladesh. The built-up area over the trajectory of the cyclone and its proximity, including eastern parts of the Kolkata metropolitan area, was considerably affected by the cyclone due to the high population density and poor structural and community planning. Although the regions with close proximities to cyclones' trajectory (2033 km2 area under <2 km proximity) were affected severely, the presence of mangrove forest in Sundarban substantially reduced the magnitude of the tropical cyclone. A considerable decrease (~30%) in aerosol optical depth (AOD) in April-May 2020 as compared to that in 2019 is considered one of the major causes of the development of the warm pool and cyclogenesis in the Bay of Bengal. The number of COVID-19 cases increased by ~70% in the post-cyclonic period (29 May 2020) compared to that in the pre-cyclonic period (19 May 2020) illustrating the impact of the cyclonic hazard.

Convergence of climate-driven hurricanes and COVID-19: The impact of 2020 hurricanes Eta and Iota on Nicaragua.

The 2020 Atlantic hurricane season was notable for a record-setting 30 named storms while, contemporaneously, the COVID-19 pandemic was circumnavigating the globe. The active spread of COVID-19 complicated disaster preparedness and response actions to safeguard coastal and island populations from hurricane hazards. Major hurricanes Eta and Iota, the most powerful storms of the 2020 Atlantic season, made November landfalls just two weeks apart, both coming ashore along the Miskito Coast in Nicaragua's North Caribbean Coast Autonomous Region. Eta and Iota bore the hallmarks of climate-driven storms, including rapid intensification, high peak wind speeds, and decelerating forward motion prior to landfall. Hurricane warning systems, combined with timely evacuation and sheltering procedures, minimized loss of life during hurricane impact. Yet these protective actions potentially elevated risks for COVID-19 transmission for citizens sharing congregate shelters during the storms and for survivors who were displaced post-impact due to severe damage to their homes and communities. International border closures and travel restrictions that were in force to slow the spread of COVID-19 diminished the scope, timeliness, and effectiveness of the humanitarian response for survivors of Eta and Iota. Taken together, the extreme impacts from hurricanes Eta and Iota, compounded by the ubiquitous threat of COVID-19 transmission, and the impediments to international humanitarian response associated with movement restrictions during the pandemic, acted to exacerbate harms to population health for the citizens of Nicaragua.