Background: Effective risk communication is critical to help vulnerable groups prepare for increasing health threats from climate change, such as extreme heat and flooding. Message content, delivery mechanisms, and messenger trust all play a role in effective communication and are particularly important during health emergencies. Cities that have diverse populations in terms of culture and health-related risk factors face additional challenges targeting communication about various hazards to vulnerable communities in a way that is timely, effective, and culturally competent. Methods: This review assesses current knowledge and gaps relating to communication of health risks, particularly surrounding life-threatening flooding events, to diverse urban populations facing climate-related hazards. It uses New York City (NYC) as a case study in terms of emergency-related communication successes and failures. Results: Diverse populations necessitate targeted communication strategies and emergency planning that consider language, culture, communication methods, and access needs. Vulnerability, messenger trust, and message effectiveness may vary, and timing is an important consideration. Conclusion: The effectiveness of risk messages and decisions depends on cultural considerations, location, resource access, and timing. Although NYC’s renter majority, public transit dependence, and diversity distinguish it from other cities, these considerations can be applied widely in strategic communication to reduce adverse health outcomes.

Background: Flooding in New York City is an increasing challenge. Recent storm events, such as Hurricane Ida, brought flash floods to the city for the first time, with property damage and deaths. The identification of vulnerable populations and how to increase flood resilience to coastal and pluvial events are climate change adaptation goals for city officials, bureaucrats, scholars, and stakeholders. Methods: This analysis examines coastal and pluvial flood vulnerability by census tract in New York City. A variety of data sources are combined to create flood vulnerability maps using the exposure-sensitivityadaptive capacity framework. A principal components analysis (PCA) with orthogonal rotation of social variables identifies four distinct hazard-sensitive populations clustered in different parts of the city. Publicly provided adaptive capacity resource (transportation and evacuation, health, communications and information, and hazard mitigation) accessibility is defined by distance. Moderate and extreme flooding levels from coastal and pluvial storm events define exposure. Results: We identify specific areas in the city where flood exposure and hazard sensitivity are high and access to adaptive capacity resources is low. These locations are defined as high flood-vulnerable areas. Within the high flood-vulnerable areas, there are differences in the size of hazard-sensitive group populations (Hispanic poor, Asian immigrant, elderly living in high-rise buildings, and African American low-income). Conclusions: The spatial combination of these variables identifies locations where targeted policies can promote hazard resilience. Our results illustrate a potential model to address and enhance flood vulnerability policy in the city.

This chapter of the New York City Panel on Climate Change 4 (NPCC4) report provides an overview of energy trends in New York City and the State of New York, as well as accompanying challenges and barriers to the energy transition-with implications for human health and wellbeing. The link between energy trends and their impact on health and wellbeing is brought to the fore by the concept of "energy insecurity," an important addition to the NPCC4 assessment.

This chapter of the New York City Panel on Climate Change 4 (NPCC4) report discusses the many intersecting social, ecological, and technological-infrastructure dimensions of New York City (NYC) and their interactions that are critical to address in order to transition to and secure a climate-adapted future for all New Yorkers. The authors provide an assessment of current approaches to "future visioning and scenarios" across community and city-level initiatives and examine diverse dimensions of the NYC urban system to reduce risk and vulnerability and enable a future-adapted NYC. Methods for the integration of community and stakeholder ideas about what would make NYC thrive with scientific and technical information on the possibilities presented by different policies and actions are discussed. This chapter synthesizes the state of knowledge on how different communities of scholarship or practice envision futures and provides brief descriptions of the social-demographic and housing, transportation, energy, nature-based, and health futures and many other subsystems of the complex system of NYC that will all interact to determine NYC futures.

Energy plays an integral role in New Yorkers' lives. It powers the economy, moves people and goods, keeps homes and workplaces at a livable temperature, and runs critical infrastructure that keeps people healthy and safe. Reliable energy systems are easy to take for granted, but many aspects of these systems are vulnerable to weather and climate hazards. This chapter discusses how climate change is affecting and will increasingly affect New York State's energy supply, delivery, and end uses. It provides insights into current and future climate vulnerabilities as New York's energy system transitions to clean energy sources. This assessment also highlights opportunities to adapt current and future energy systems and to build resilience to climate impacts.

New York City (NYC) faces many challenges in the coming decades due to climate change and its interactions with social vulnerabilities and uneven urban development patterns and processes. This New York City Panel on Climate Change (NPCC) report contributes to the Panel's mandate to advise the city on climate change and provide timely climate risk information that can inform flexible and equitable adaptation pathways that enhance resilience to climate change. This report presents up-to-date scientific information as well as updated sea level rise projections of record. We also present a new methodology related to climate extremes and describe new methods for developing the next generation of climate projections for the New York metropolitan region. Future work by the Panel should compare the temperature and precipitation projections presented in this report with a subset of models to determine the potential impact and relevance of the "hot model" problem. NPCC4 expects to establish new projections-of-record for precipitation and temperature in 2024 based on this comparison and additional analysis. Nevertheless, the temperature and precipitation projections presented in this report may be useful for NYC stakeholders in the interim as they rely on the newest generation of global climate models.

While nations have made commitments to address climate change, scholars estimate that even if these commitments are met, there remains an emissions gap between where we are and where we want to be to keep the globe under 1.5°C. Cities around the world are working to reduce this gap. Asian cities are large greenhouse gas (GHG) emitters and will be so over the next few decades. It is therefore urgent to identify ways in which the region’s cities can become more efficient and less polluting. This study is an APN research project that examines the GHG emissions at the sub-city level across 5 Asian cities (Tokyo, Beijing, Taipei, Seoul and Bangkok) as well as in New York City. The attempt is to identify potential strategies for low-carbon pathways. The research demonstrates that, in most cases, national and urban emissions are increasing, although the APN research teams identified stable emissions over the past few years in Beijing and Tokyo. However, the emissions profiles are different. Therefore, reducing emissions will require different strategies across the region’s cities. The study identifies some general policy priorities for cities based on the results of case studies.

EDITORIAL article Front. Built Environ., 18 April 2023Sec. Urban Science Volume 9 - 2023 | https://doi.org/10.3389/fbuil.2023.1194813

Electrical power outages are of increasing interest to US urban scholars, government officials and stakeholders, as they have increased in number and duration with significant health and economic, among other, impacts. This analysis examines reports of power outages in New York City in relation to socioeconomic and health characteristics of neighborhoods. Using the city's 311-call database we examine complaint calls for power outages from 2014 to 2022. While 311-calls for power outages occur all year long, volume trended higher during the warmer months (June, July and August), and as minimum daily temperatures exceeded 20 degrees C (68 degrees F), the number of calls increased dramatically. Spatial clusters of high call areas were in Census tracts with high energy burdens, lower-income households, and high percentages of people of color. Furthermore, we found the higher call areas were associated with higher vulnerability to heat-exacerbated deaths. As climate change is expected to raise temperatures and increase the frequency and intensity of heat waves around the world, and as power outages are becoming more common, these findings will help to provide guidance for adaptation and energy reliability policies in New York City and have implications for other cities globally.

Over the past decades, the world has experienced increasing heatwave intensity, frequency, and duration. This trend is projected to increase into the future with climate change. At the same time, the global population is also projected to increase, largely in the world’s cities. This urban growth is associated with increased heat in the urban core, compared to surrounding areas, exposing residents to both higher temperatures and more intense heatwaves than their rural counterparts. Regional studies suggest that Asia and Africa will be significantly affected. How many people may be exposed to levels of extreme heat events in the future remains unclear. Identifying the range in number of potentially exposed populations and where the vulnerable are located can help planners prioritize adaption efforts. We project the ranges of population exposed to heatwaves at varying levels to 2,100 for three future periods of time (2010–2039, 2040–2069, 2070–2099) using the Shared Socio-Economic Pathways (SSPs) and the Representative Concentration Pathways (RCPs). We hypothesize that the largest populations that will be exposed to very warm heatwaves are located in Asia and Africa. Our projections represent the warmest heatwaves for 15 days during these three periods. By the 2070–2099 period, the exposure levels to extreme heatwaves (>42°) exceed 3.5 billion, under the sustainability scenario (RCP2.6-SSP1). The number of those exposed in cities climbs with greater projected climate change. The largest shares of the exposed populations are located in Southern Asia and tropical countries Western and Central Africa. While this research demonstrates the importance of this type of climate change event, urban decision-makers are only recently developing policies to address heat. There is an urgent need for further research in this area.

Cities are at the forefront of climate change action and planning for futures that are concomitantly more resilient and equitable, making local goals imperative for global sustainability. Under the multiple challenges of changing climatic, ecological and socio-economic conditions, cities need the means to meet these goals. We know cities are and will continue to be points of concentrated and diverse populations, socioeconomic vulnerability, amplified exposure, transformed ecosystems and are responsible for the bulk of the world’s greenhouse gas emissions. Yet, much is also unknown and intrinsically uncertain about urban futures: there is a range of potential plausible futures which have differing implications for both potential mitigation and adaptation actions. To better assess these plausible futures, the “global change” research community developed a framework including scenarios that are applicable for global and regional policy, entitled the Shared Socio-economic Pathways (SSPs) and scenarios exploring future emissions that will drive climate change, entitled Representative Concentration Pathways (RCPs). Importantly, this global scale framework does not include specific city-level perspectives or data at the spatial scales necessary to address questions of local relevance. While the SSPs address many of the key population and socioeconomic drivers of climate change, they do not address important concerns that are particularly relevant to cities, such as racial justice, ecosystem change or migration. Nevertheless, city-level impacts will evolve, in part, as a function of the global scale change characterized by the SSPs, and in part based on demographic and social processes already underway. As such, applying a modification of this framework to cities has the potential to help limit local climate impacts, and create a more resilient, equitable city. To address these needs and respond to city and regional stakeholders, we propose a framework for science-based narratives and quantitative projections for cities and metropolitan areas, such as Greater New York City. In this paper, we review a wide-range of existing approaches to generate estimates of future populations and identify their vulnerabilities to climate-change hazards, ranging from subnational population projections or the spatially-explicit allocation of populations linked to SSPs for the US and selected cities, city-specific population forecasting without climate considerations, and participatory approaches to future scenario development and fine-scale, within-city land use change models. By showcasing the strengths and limitations of various approaches and modeling efforts, their spatial and temporal scales, and thematic breadth, we propose a novel framework that leverages state-of-the art quantitative approaches and couples it with stakeholder engagement that can help cities plan equitably under uncertainty.

During early 2020, the world encountered an extreme event in the form of a new and deadly disease, COVID-19. Over the next two years, the pandemic brought sickness and death to countries and their cities around the globe. One of the first and initially the hardest hit location was New York City, USA. This article is an introduction to the Special Issue in this journal that highlights the impacts from and responses to COVID-19 as an extreme event in the New York City metropolitan region. We overview the aspects of COVID-19 that make it an important global extreme event, provide brief background to the conditions in the world, and the US before describing the 10 articles in the issue that focus on conditions, events and dynamics in New York City during the initial phases of the pandemic.

Coronavirus disease 2019 (COVID-19) has impacted cities around the world. Global cities theory suggests that cities articulated to the global economy should be affected by such flows similarly. We start from this perspective and examine the impacts and outcomes of COVID-19 in three global cities: New York City, London and Tokyo. Our results focus on the speed, intensity, scale and characteristics of COVID-19 related cases and deaths in these cities and their respective countries. We find that while there are similarities between the experiences of global cities, there are also significant differences. The differences can be partially explained by policy, socio-economic and cultural differences. Our findings suggest that cities articulated to the global system could benefit from developing their own locally unique early warning and emergency response system, integrated with but separate from national systems.

This research describes the change in temperatures across approximately 270 tropical cities from 1960 to 2020 with a focus on urban warming. It associates urban growth indicators with temperature variations in tropical climate zones (tropical rainforest, tropical monsoon, and tropical wet-dry savanna). Our findings demonstrate that over time while temperatures have increased across the tropics, urban residents have experienced higher temperatures (minimum and maximum) than those living outside of cities. Moreover, in certain tropical zones, over the study period, temperatures have risen faster in urban areas than the background (non-urban) temperatures. The results also suggest that with continuing climate change and urban growth, temperatures will continue to rise at higher than background levels in tropical cities unless mitigation measures are implemented. Several fundamental characteristics of urban growth including population size, population density, infrastructure and urban land use patterns are factors associated with variations in temperatures. We find evidence that dense urban forms (compact residential and industrial developments) are associated with higher temperatures and population density is a better predictor of variation in temperatures than either urban population size or infrastructure in most tropic climate zones. Infrastructure, however, is a better predictor of temperature increases in wet-dry savanna tropical climates than population density. There are a number of potential mitigation measures available to urban managers to address heat. We focus on ecological services, but whether these services can address the projected increasing heat levels is unclear. More local research is necessary to untangle the various contributions to increasing heat in cities and evaluate whether these applications can be effective to cool tropical cities as temperature continue to rise. Our methods include combining several different datasets to identify differences in daily, seasonal, and annual maximum and minimum temperatures.

Urbanization and climate change are among the most important global trends affecting human well-being during the twenty-first century. One region expected to undergo enormous urbanization and be significantly affected by climate change is Africa. Studies already find increases in temperature and high temperature events for the region. How many people will be exposed to heat events in the future remains unclear. This paper attempts to provide a first estimate of the number of African urban residents exposed to very warm 15-day heat events (>42 degrees C). Using the Shared Socio-economic Pathways and Representative Concentration Pathways framework we estimate the numbers of exposed, sensitive (those younger than 5 and older than 64 years), and those in low-income nations, with gross national products of $4000 ($2005, purchasing power parity), from 2010 to 2100. We examine heat events both with and without urban heat island estimates. Our results suggest that at the low end of the range, under pathways defined as sustainable (SSP 1) and low relative levels of climate change (RCP 2.6) without including the urban heat island effect there will be large populations (>300 million) exposed to very warm heat wave by 2100. Alternatively, by 2100, the high end exposure level is approximately 2.0 billion for SSP 4 under RCP 4.5 where the urban heat island effect is included.

Cities in South Asia commonly experience high heat events. These so-called heat waves, however, are increasing in intensity and are projected to increase in frequency, as the climate continues to change. Given the large and growing urban population in the region, urban planners need information on the state and trends of urban heat, the risk of this heat to human wellbeing, and ways to modify heat within the city. This chapter attempts to broadly address these issues by providing an overview of the state and trends of urban heat, urban heat-island formation, urbanization, climate change-related future heat, human risk to heat waves, and the potential for ecosystem mitigation in South Asia. The chapter complements other chapters in this volume by providing the background to the importance of future heat shock events and the potential for blue-green infrastructure to address these hazards.