Effects Of Extreme Weather Events Research Articles

Effects of the El Niño Southern Oscillation phenomenon and sowing dates on soybean yield and on the occurrence of extreme weather events in southern Brazil

ABSTRACT Brazil accounts for 32% of world soybean production and potential yield losses related to climate variability in the country can have an adverse effect on global supply. Recent soybean production declines in Brazil (e.g. The 15.6% soybean yield drop occurred during the 2011/12 growing season) were a consequence of extreme weather events caused by the effects of the El Nino Southern Oscillation (ENSO) phenomenon. ENSO is one of the most important atmospheric-oceanic phenomena responsible for climate and crop yield variability in several agricultural producing regions of Brazil. The greatest challenge related to adapting to ENSO climate cycles is to understand how to minimize the negative impacts and take advantage of favorable conditions to improve yields. Thus, the aim of this study was to determine the spatial and temporal impacts of sowing dates and ENSO phases on soybean yield and the frequency of extreme weather events (high, low temperature and dry period) during the vegetative and reproductive soybean phenological phases in southern Brazil. For that, soybean yields for 16 different sowing dates (from September to February) were simulated using a well-calibrated crop growth and development model (CROPGRO-Soybean) for 12 locations across southern Brazil and considering historical weather series of 56 years (1961-2016). Homogeneous regions related to ENSO impacts were defined by cluster analysis to facilitate the understanding and use of the information produced. Alternative ENSO phases were found to affect the frequency of extreme weather events and soybean yields across the region studied. Potential negative ENSO effects could be minimized by adjusting the sowing windows according to the expected climate cycle. Our results revealed that ENSO impacts on soybean yields in southern Brazil vary according to the location and can be categorized into three main groups: Group I, where the impacts of the El Nino phase on soybean yield tend to be positive, and its positive impact did not vary with the different sowing dates; Group II, where the negative soybean yield anomalies were more frequent in Neutral years; and Group III, where the positive and negative impacts of ENSO phases varied with sowing dates.

Multiple Ecosystem Effects of Extreme Weather Events in the Arctic

The Arctic is getting warmer and wetter. Here, we document two independent examples of how associated extreme precipitation patterns have severe implications for high Arctic ecosystems. The events stand out in a 23-year record of continuous observations of a wide range of ecosystem parameters and act as an early indication of conditions projected to increase in the future. In NE Greenland, August 2015, one-quarter of the average annual precipitation fell during a 9-day intensive rain event. This ranked number one for daily sums during the 1996–2018 period and caused a strong and prolonged reduction in solar radiation decreasing CO2 uptake in the order of 18–23 g C m−2, a reduction comparable to typical annual C budgets in Arctic tundra. In a different type of event, but also due to changed weather patterns, an extreme snow melt season in 2018 triggered a dramatic gully thermokarst causing rapid transformation in ecosystem functioning from consistent annual ecosystem CO2 uptake and low methane exchange to highly elevated methane release, net source of CO2, and substantial export of organic carbon downstream as riverine and coastal input. In addition to climate warming alone, more frequent occurrence of extreme weather patterns will have large implications for otherwise undisturbed tundra ecosystems including their element transport and carbon interactions with the atmosphere and ocean.

The economic costs of Hurricane Harvey attributable to climate change

Hurricane Harvey is one of the costliest tropical cyclones in history. In this paper, we use a probabilistic event attribution framework to estimate the costs associated with Hurricane Harvey that are attributable to anthropogenic influence on the climate system. Results indicate that the “fraction of attributable risk” for the rainfall from Harvey was likely about at least a third with a preferable/best estimate of three quarters. With an average estimate of damages from Harvey assessed at about US$90bn, applying this fraction gives a best estimate of US$67bn, with a likely lower bound of at least US$30bn, of these damages that are attributable to the human influence on climate. This “bottom-up” event-based estimate of climate change damages contrasts sharply with the more “top-down” approach using integrated assessment models (IAMs) or global macroeconometric estimates: one IAM estimates annual climate change damages in the USA to be in the region of US$21.3bn. While the two approaches are not easily comparable, it is noteworthy that our “bottom-up” results estimate that one single extreme weather event contributes more to climate change damages in the USA than an entire year by the “top-down” method. Given that the “top-down” approach, at best, parameterizes but does not resolve the effects of extreme weather events, our findings suggest that the “bottom-up” approach is a useful avenue to pursue in future attempts to refine estimates of climate change damages.

Human–Environment Natural Disasters Interconnection in China: A Review

This study aimed to assess the interrelationship among extreme natural events and their impacts on environments and humans through a systematic and quantitative review based on the up-to-date scientific literature. Namely, the main goal was to add additional knowledge to the existing evidence of the impacts related to floods, droughts, and landslides on humans and the environment in China; this in order to identify knowledge gaps in research and practice to aid in improving the adaptation and mitigation measures against extreme natural events in China. In this study, 110 documents were analyzed in the evaluation of several impacts triggered by extreme events. Records were obtained from Scopus and Web of Science and examined with a text mining instrument to assess the pattern of publications over the years; the problems linked to extreme weather events were investigated, and the study gaps were discussed. This paper extends work by systematically reviewing recent evidence related to floods, droughts, and landslides in China. We listed the critical studies that focused on the impact of extreme events on both humans and the environment described in current reviews. The findings revealed that goods safety, social safety, and financial losses are of significant concern to the scientific community due to extreme natural events, which from our analysis resulted in being more frequent and intense. It is still underdeveloped to implement distant sensing and imaging methods to monitor and detect the impact of severe weather occurrences. There are still significant study gaps in the fields of the effects of extreme weather events. The analysis result shows that extreme events are increased during the time, so more in-depth investigation and efforts on adaptation, mitigation measures, and strategical governance plans are desperately required.

ENVIRONMENTAL DEGRADATION AND VIOLENT CONFLICT BETWEEN HERDERS AND FARMERS IN NIGERIA

This paper addressed the concern that the herders-farmers conflict debate in Nigeria has overlooked the role of climate change. It notes that although, commentators, especially official position on the issue usually blame it on ethnic politics, religious differences, indigene-settler wrangling, population explosion, expansion of farmland, blocking of grazing routes, ‘xenophobia’ and most recently, passage of anti-open grazing laws by some states et cetera. Conversely, as plausible as these narratives sound, they overlooked the contribution of climate change as threat multiplier in the phenomena. By overlooking this fact, they fail to capture and account for effects of extreme weather events like drought, desertification, change in precipitation and shrinking of water bodies, which compel herders to migrate southwards in search of arable land, water points and pasture for their cattle. Designed as a desk study, the paper noted the point that it was the struggle over access and use rights in addition to attempt by both parties to secure the available natural resources for themselves that usually result in these conflicts.

Determining the Effect of Extreme Weather Events on Human Participation in Recreation and Tourism: A Case Study of the Toronto Zoo

This study devises a novel approach for defining extreme weather events and assessing their effects on human participation in recreation and tourism, based on a case study of attendance at the Toronto Zoo (Toronto, ON, Canada). Daily zoo attendance data from 1999 to 2018 was obtained and analyzed in connection with daily weather data from local weather stations for the maximum temperature, minimum temperature, total precipitation, and maximum wind speed. The “climatic distance” method, used for evaluating representative weather stations for case studies in applied climatology, was employed to rank and select surrounding weather stations that most accurately captured daily weather observations recorded at the Toronto Zoo from 1990 to 1992. Extreme weather events can be defined as lying in the outermost (most unusual) 10 percent of a place’s history. Using this definition as the foundation, a percentile approach was developed to identify and assess the effects of extreme weather events across the following thresholds: the 99th percentile, the 95th percentile, and the 90th percentile, as well as less than the 1st percentile, less than the 5th percentile, and less than the 10th percentile. Additionally, revealed, theoretical, and binary thresholds were also assessed to verify their merit and determine their effects, and were compared to the extreme weather events defined by the percentiles approach. Overall, extreme daily weather events had statistically significant negative effects on zoo attendance in Toronto, apart from a few cases, such as the positive effect of usually warm daytime temperatures in the winter and usually cool nighttime temperatures in the summer. The most influential weather event across all seasons was extremely hot temperatures, which has important implications for climate change impact assessments.

How Does Climate Change Affect the Transition of Power Systems: The Case of Germany

The effects of extreme weather events, such as heat waves and droughts are taken into account in both global and European policies. Accordingly, the protection of critical infrastructures and in particular, the resilience of the energy sector was the subject of intense research. There are regional differences in the degree of exposure to extreme events. In Northern Europe, their intensity has increased dramatically within a decade. In our analysis we identify emerging risks of extreme weather events, in particular, droughts and high temperatures, for the German power sector. Furthermore, we consider how European policy addressed these severe risks. Our analysis is based on extensive datasets covering temperature and drought data for the last 40 years. We find evidence of a higher frequency of power plants outages as a consequence of droughts and high temperatures. We investigate increases in the wholesale electricity price and price volatility and develop a capacity-adjusted drought index. The results are used to assess the monetary loss of power plant outages due to heatwaves and droughts. We stress that increasing frequencies of such extreme weather events will aggravate the observed problem, especially with respect to the transition of the power sector.

How does Climate Change Affect the Transition of Power Systems: The Case of Germany

The effects of extreme weather events, such as heat waves and droughts are taken into account in both global and European policies. Accordingly, the protection of critical infrastructures and in particular, the resilience of the energy sector was the subject of intense research. There are regional differences in the degree of exposure to extreme events. In Northern Europe, their intensity has increased dramatically within a decade. In our analysis we identify emerging risks of extreme weather events, in particular, droughts and high temperatures, for the German power sector. Furthermore, we consider how European policy addressed these severe risks. Our analysis is based on extensive datasets covering temperature and drought data for the last 40 years. We find evidence of a higher frequency of power plants outages as a consequence of droughts and high temperatures. We investigate increases in the wholesale electricity price and price volatility and develop a capacity-adjusted drought index. The results are used to assess the monetary loss of power plant outages due to heatwaves and droughts. We stress that increasing frequencies of such extreme weather events will aggravate the observed problem, especially with respect to the transition of the power sector.

Impact of heatwaves and cold spells on the morbidity of respiratory diseases: A case study in Lanzhou, China

More than four hundred million people suffer from respiratory diseases each year. Respiratory diseases are associated with a large disease burden. Heatwaves and cold spells, the two most common extreme weather events, have been shown to have crucial negative effects on the prevalence of respiratory diseases. However, impacts of extreme weather on the prevalence of respiratory diseases has been largely overlooked in western China, where more intense and frequent extreme temperature events have been occurring over the past decades. This research gap will obtain an attribution bias in the effects of extreme weather events on the prevalence of respiratory diseases. Therefore, in this study, we analyzed the impact of heatwaves and cold spells on the morbidity of respiratory diseases using a distributed lag nonlinear model with daily disease cases from 2013 to 2016 in Lanzhou, one of the largest cities in western China. A reverse U-shaped relationship depicted the relationship between temperature and the morbidity of respiratory diseases. The highest relative risk was found at 2.6 °C by 1.15 (95% confidence interval: 1.09–1.21). Furthermore, we found a significant decrease in the relative risk for heatwaves and a significant increase in the relative risk of cold spells when the temperature exceeded the corresponding threshold by 1 °C. Heatwaves and cold spells play harvest effects on the morbidity of respiratory diseases. Our study suggest that the relative risk of respiratory diseases will increase as the climate warms in the future, and thus a preventive system is needed for individuals and medical policy-makers.

Assessing the potential effect of extreme weather on water quality and disinfection by-product formation using laboratory simulation

Increased frequency and severity of extreme weather events (i.e., floods and droughts) combined with higher temperatures can threaten surface water quality and downstream drinking water production. This study characterized the effects of extreme weather events on dissolved organic matter (DOM) washout from watershed soils and the corresponding contribution to disinfection by-product (DBP) precursors under simulated weather conditions. A laboratory simulation was performed to assess the effects of temperature, drought, rainfall intensity, sea level rise, and acid deposition on the amount of DOM released from soil samples. DBP formation potentials (DBPFPs) were obtained to assess the effect of extreme weather events on DBP formation and drinking water quality. The results demonstrated that the dissolved organic carbon (DOC) and carbonaceous DBP levels increased with increasing temperature in a dry (drought) scenario. Regardless of the watershed from which a soil sample was obtained and the incubation temperature during rewetting or chlorination processes, the DOC and carbonaceous DBP levels also increased with increasing temperature. Brominated DBP formation was increased when bromide was present during the rewetting of soil, indicating the effect of sea level rise. When bromide was present during the chlorination of water for DBPFP tests, only the level of brominated DBPs increased. Acid deposition had various effects under different weather conditions. The results of heavy rainfall simulations suggested that water quality deteriorates at the beginning of an extreme rainfall event. Abundant DOM was washed out of soil, leading to a peak in the DBPFP level. The level of DOM in seepage water was less than that of the surface runoff water during rainfall. The situation was more severe when the rainfall came after a long drought and the drought–rewetting cycle effect occurred.

ACTIONS TO REDUCE RISK OF OLDER ADULTS DURING EXTREME WEATHER EVENTS THAT THREATEN HEALTH AND LIFE

Climate change places many older adults at unique risk for adverse, potentially life-threatening consequences. Compared to younger adults, older adults are more susceptible to the effects of extreme weather events and at greater risk for heat stroke and hypothermia. With advanced age, some people have vulnerabilities, such as social isolation and physical and mental health conditions that predispose them to a greater level of danger. Loss of power, that leaves people without functioning cooling or heating systems, can cause death because it exacerbates preexisting medical conditions and impairs thermoregulatory function for those with medical illnesses or taking certain medications. Many older adults who function independently may not self-identify as being vulnerable and take necessary precautions to remain safe. This presentation will describe recent research that found that many older adults are unaware of hypothermia and hyperthermia symptoms and the actions needed to maintain health and life.

Perceptions of Climate Change and Adaptation of Climate Smart Technology by the Tea Smallholders: A Case Study of Ratnapura District in Sri Lanka

Climate change impacts such as rainfall variability, rise in ambient temperature, extreme dry spells and excessive wet periods cause low productivity and quality of tea. Ratnapura District in Sri Lanka, having the largest number of tea smallholders, is highly vulnerable to natural disasters and other negative impacts of climate change. This study was conducted to assess the status of climate change using long term meteorological data, to determine the perception of tea smallholders on short term changes in the climate and to assess the level of adaptation of climate-smart technologies by tea smallholders. Four Divisional Secretariat Divisions were selected for the study. Using multistage sampling, a hundred farmers were selected for the social survey. Meteorological data for 42 years was collected from the Department of Agriculture Sri Lanka. Both descriptive and inferential statistics were used in the analysis. Results showed that there was a significant (p<.05) increasing trend in daily maximum temperature. A slightly increasing trend in consecutive wet days was also observed. The perception of the majority of smallholders about changes in daytime temperature, number of wet days and rainfall distribution was in line with actual changes. Further, the overall level of adaptation to climate-smart technologies was at a moderate level. Shade management practices were at a higher level while moisture conservation practices were at a lower level. It was pivotal to make people aware of the severity of the impacts of climate change on their livelihoods and introduce climate-smart technologies to manage the consequences of extreme weather events.

The global effect of extreme weather events on nutrient supply: a superposed epoch analysis

To date, the effects of extreme weather events on nutrient supply within the population have not been quantified. In this study, we investigated micronutrient, macronutrient, and fibre supply changes during 175 extreme weather events within 87 countries in the year that a major extreme weather event occurred, with a targeted focus on low-income settings. We collected data from the International Disasters Database and the Global Expanded Nutrient Supply model for the period 1961-2010, and applied superposed epoch analysis to calculate the percentage change in nutrient supply during the year of an extreme weather event relative to its historical context. We composited globally and by subgroup (EU, landlocked developing countries, least developed countries, low-income food deficit countries, and net food-importing developing countries). Lastly, we reported nutrient supply changes in terms of recommended dietary allowance for children aged 1-3 years. Globally, all micronutrient supplies had a modest negative percentage change during the year of an extreme weather event; of these effects, those that reached an α=0·05 significance level included calcium, folate, thiamin, vitamin B6, and vitamin C, with nutrient supply changes ranging from -0·40 to -1·73% of the average supply. The effect of an extreme weather event was especially magnified among landlocked developing countries and low-income food deficit countries, with significant nutrient supply changes ranging from -1·61 to -7·57% of the average supply. Furthermore, the observed nutrient supply deficits in landlocked developing countries constituted a large percentage (ranging from 1·95 to 39·19%) of what a healthy child's sufficient average dietary intake should be. The global effects of extreme weather events on nutrient supply found in this study are modest in isolation; however, in the context of nutrient needs for healthy child development in low-income settings, the effects observed are substantial. Australian-American Fulbright Commission.

Assessing the Impacts of Drought on Grassland Net Primary Production at the Global Scale

Quantitatively assessing the impacts of drought on grassland has significant implications to understand the degradation mechanism and prevention degraded grassland. In this study, we analyzed the relationship between grassland drought and grassland Net Primary Productivity (NPP) based on the self-calibrated Palmer Drought Severity Index (scPDSI) from 1982 to 2008. The results showed that the global grassland scPDSI value had a slightly increasing trend with the rate of 0.0119 per year (R2 = 0.195), indicating that the global grassland drought lighter to some extent during study period. Moreover, the correlation coefficient between annual grassland NPP and scPDSI was from −0.83 to 0.92. The grassland NPP decreased under mild drought from 1992 to 1996. Additionally, the correlation coefficient between scPDSI and NPP for each grassland type was: Closed Shrublands > Non-woody grassland > Savannas > Open Shrublands > Woody Savannas, indicating that drought had difference influences on the different grassland types. Our results might provide the underlying insights needed to be guide for the effects of extreme weather events on grassland NPP.

Effect of Extreme Weather Events on the Sedimentation of the Bay of Samaná, Dominican Republic (1900–2016)

The Bay of Samaná, formed by tectonism and sedimentation, is delimited to the north by the peninsula of the same name, to the south by the north slope of the Eastern Mountain Range and Los Haitises National Park, to the east by the Atlantic Ocean, and to the west by the ancient Gran Estero, today the Lower Yuna. There follows a process of continuous degradation by the existing tectonic forces and the sediment contributions by the Yuna, Yabón, and La Yeguada rivers to the south as well as by the landslides of the mountainous area of the Samaná Peninsula, during periods of storms and hurricanes. The coastal area of Samaná Bay has altered by 2.17 km2 at the mouth of the Yuna River from 2003–2015. The high turbidity level has affected coral reefs and marine species.  The  mangroves  are  lost  faster  than  they  are  regenerated  by  the  coastline’s change. Variations in the elemental compositions of calcium and iron show the terrigenous influence on the dynamics of the bay during Extreme Weather Events (EWP) in the river basins that flow into it. Abrupt changes in the rainfall regime produced an equal change in the estuary sedimentation regime, according to the 210Pb. In the 2007–2016 period, a column of sediment that reached 38 cm and a 12 cm to 8.4 km column were deposited 4 km southeast of the municipality of Sánchez and east of the mouth of the Yuna River. The Sedimentary Accumulation Rate is very high, and
 the content of heavy metals exceeds the threshold values of Table SQuirt.

Analysis of the Effects of High Precipitation in Texas on Rainfed Sorghum Yields

Most of the recent studies on the consequences of extreme weather events on crop yields are focused on droughts and warming climate. The knowledge of the consequences of excess precipitation on the crop yield is lacking. We attempted to fill this gap by estimating reductions in rainfed grain sorghum yields for excess precipitation. The historical grain sorghum yield and corresponding historical precipitation data are collected by county. These data are sorted based on length of the record and missing values and arranged for the period 1973–2003. Grain sorghum growing periods in the different parts of Texas is estimated based on the east-west precipitation gradient, north-south temperature gradient, and typical planting and harvesting dates in Texas. We estimated the growing season total precipitation and maximum 4-day total precipitation for each county growing rainfed grain sorghum. These two parameters were used as independent variables, and crop yields of sorghum was used as the dependent variable. We tried to find the relationships between excess precipitation and decreases in crop yields using both graphical and mathematical relationships. The result were analyzed in four different levels; 1. Storm by storm consequences on the crop yield; 2. Growing season total precipitation and crop yield; 3. Maximum 4-day precipitation and crop yield; and 4. Multiple linear regression of independent variables with and without a principal component analysis (to remove the correlations between independent variables) and the dependent variable. The graphical and mathematical results show decreases in rainfed sorghum yields in Texas for excess precipitation could be between 18% and 38%.

Extreme Weather Events in Agriculture: A Systematic Review

Despite the increase of publications focusing on the consequences of extreme weather events (EWE) for the agricultural sector, a specific review of EWE related to agriculture is missing. This work aimed at assessing the interrelation between EWE and agriculture through a systematic quantitative review of current scientific literature. The review analysed 19 major cropping systems (cereals, legumes, viticulture, horticulture and pastures) across five continents. Documents were extracted from the Scopus database and examined with a text mining tool to appraise the trend of publications across the years, the specific EWE-related issues examined and the research gaps addressed. The results highlighted that food security and economic losses due to the EWE represent a major interest of the scientific community. Implementation of remote sensing and imagery techniques for monitoring and detecting the effects of EWE is still underdeveloped. Large research gaps still lie in the areas concerning the effects of EWE on major cash crops (grapevine and tomato) and the agronomic dynamics of EWE in developing countries. Current knowledge on the physiological dynamics regulating the responses of main crops to EWE appears to be well established, while more research is urgently needed in the fields of mitigation measures and governance systems.

The Effect of Natural Disasters on Cancer Care: A Systematic Review

Introduction:As the incidence of cancer and the frequency of extreme weather events rise, disaster mitigation is becoming increasingly relevant to oncology care.Aim:To investigate the effect of natural disasters on cancer care and the associated health effects on patients with cancer through the means of a systematic review.Methods:Between database inception and November 12, 2016, Embase, ScienceDirect, MEDLINE, Scopus, PsycINFO, Web of Science, and CINAHL were searched for articles. Those identifying the effect of natural disasters on oncology services, or the associated health implications for patients with cancer, were included. Only articles published in English were included. Data extraction was done by two authors independently and then verified by all authors. The effects of disaster events on oncology services, survival outcomes, and psychological issues were assessed.Results:Natural disasters cause substantial interruption to the provision of oncology care. Of the 4,593 studies identified, only 85 articles met all the eligibility criteria. Damage to infrastructure, communication systems, medication, and medical record losses substantially disrupt oncology care. The effect of extreme weather events on survival outcomes is limited to only a small number of studies, often with inadequate follow-up periods.Discussion:To the best the authors’ knowledge, this is the first systematic review to assess the existing evidence base on the health effects of natural disaster events on cancer care. Disaster planning must begin to take into consideration patients with cancer.

Invasion windows for a global legume invader are revealed after joint examination of abiotic and biotic filters.

Successful alien plant invasion is influenced by both climate change and plant-plant interactions. We estimate the single and interactive effects of competition and extreme weather events on the performance of the global legume invader Lupinus polyphyllus (Lindl.). In three experimental studies we assessed (i) the stress tolerance of seedling and adult L.polyphyllus plants against extreme weather events (drought, fluctuating precipitation, late frost), (ii) the competitive effects of L.polyphyllus on native grassland species and vice versa, and (iii) the interactive effects of extreme weather events and competition on the performance of L.polyphyllus. Drought reduced growth and led to early senescence of L.polyphyllus but did not reduce adult survival. Fluctuating precipitation events and late frost reduced the length of inflorescences. Under control conditions, interspecific competition reduced photosynthetic activity and growth of L.polyphyllus. When subjected to competition during drought, L.polyphyllus conserved water while simultaneously maintaining high assimilation rates, demonstrating increased water use efficiency. Meanwhile, native species had reduced performance under drought. In summary, the invader gained an advantage under drought conditions through a smaller reduction in performance relative to its native competitors but was competitively inferior under control conditions. This provides evidence for a possible invasion window for this species. While regions of high elevation or latitude with regular severe late frost events might remain inaccessible for L.polyphyllus, further spread across Europe seems probable as the predicted increase in drought events may favour this non-native legume over native species.

Urban bus ridership, income, and extreme weather events

Climate change is projected to worsen weather extremes, such as heat waves and days of heavy precipitation, which could pose serious health and economic risks to U.S. cities. These extreme weather events could also affect urban mobility, since people who walk or bike may shift to public transit or avoid travel if they cannot afford a vehicle. To address these concerns, this study examines the effects of extreme weather events on bus ridership and the extent to which this relationship varies by income and destination. This study analyzes highly detailed micro-level bus data between 2012 and 2017 for a county in the Pacific Northwest using a negative binomial regression model. Results suggest modest reductions in bus ridership on very hot and cold days, as well as on days with heavy rainfall, with impacts differing between weekdays and weekends. Findings also show that bus ridership is more sensitive to extreme weather events in lower-income areas relative to the wealthiest neighborhoods, which may be partly driven by a large university student population who can ride the bus for free. Finally, results show that bus ridership around commercial areas and parks increases on very cold days and days with heavy precipitation, reinforcing the importance of public transit during these weather events. These results suggest extreme weather events affect urban mobility, with greater impacts in lower-income neighborhoods, parks and commercial areas. Transit agencies and policymakers should consider ways to increase accessibility and mobility during these weather events, especially for lower-income households.