Publications

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2017
Vanos, JK, Herdt AJ, Lochbaum MR.  2017.  Effects of physical activity and shade on the heat balance and thermal perceptions of children in a playground microclimate. Building and Environment. 126:119-131.   10.1016/j.buildenv.2017.09.026   AbstractWebsite

Outdoor thermal comfort (TC) is an important parameter in assessing the value and health utility of a recreational space. Given the public health significance of child heat illness, the ability to model children's heat balance and TC during activity has received little attention. The current pilot study tests the performance of an outdoor human heat balance model on children playing in warm/hot outdoor environments in sun and shade. Fourteen children aged 9-13 participated in the 8-day study in Texas in spring 2016, performing physical activity while wearing heartrate monitors and completing thermal perception surveys (e.g., actual thermal sensation (ATS)). Surveys were compared to predicted thermal sensation (PTS) based on principles of human-environment heat exchange using personal data and a suite of on-site microclimate information. Results demonstrate the model to significantly predict ATS votes (Spearman's rho = 0.504). Subjective preferred change was also significantly correlated to modeled PTS (rho = -0.607). Radiation, air temperature, windspeed, and level of tiredness were significant predictors of ATS. Finally, the mean human energy balance was significantly lower in the shade (-168 W m(-2)), thus lowering heat stress potential, with the model predicting ATS with little-to-no error (0.2 and 0.0 scale error units in sun and shade, respectively). This study demonstrates an ability to estimate a child's heat balance while accounting for changes in major heat contributors (e.g., radiation, metabolism), and is the first study to evaluate TC of children during activity in outdoor built environments. New insights of heat perception may aid in recognition of often under-recognized heat stress. (C) 2017 Elsevier Ltd. All rights reserved.

Mehdipoor, H, Vanos JK, Zurita-Milla R, Cao GF.  2017.  Short communication: emerging technologies for biometeorology. International Journal of Biometeorology. 61:S81-S88.   10.1007/s00484-017-1399-9   AbstractWebsite

The first decade of the twenty-first century saw remarkable technological advancements for use in biometeorology. These emerging technologies have allowed for the collection of new data and have further emphasized the need for specific and/or changing systems for efficient data management, data processing, and advanced representations of new data through digital information management systems. This short communication provides an overview of new hardware and software technologies that support biometeorologists in representing and understanding the influence of atmospheric processes on living organisms.

Grundstein, A, Knox JA, Vanos J, Cooper ER, Casa DJ.  2017.  American football and fatal exertional heat stroke: a case study of Korey Stringer. International Journal of Biometeorology. 61:1471-1480.   10.1007/s00484-017-1324-2   AbstractWebsite

On August 1, 2001, Korey Stringer, a Pro Bowl offensive tackle for the Minnesota Vikings, became the first and to date the only professional American football player to die from exertional heat stroke (EHS). The death helped raise awareness of the dangers of exertional heat illnesses in athletes and prompted the development of heat safety policies at the professional, collegiate, and interscholastic levels. Despite the public awareness of this death, no published study has examined in detail the circumstances surrounding Stringer's fatal EHS. Using the well-documented details of the case, our study shows that Stringer's fatal EHS was the result of a combination of physiological limitations, organizational and treatment failings, and extreme environmental conditions. The COMfort FormulA (COMFA) energy budget model was used to assess the relative importance of several extrinsic factors on Stringer's EHS, including weather conditions, clothing insulation, and activity levels. We found that Stringer's high-intensity training in relation to the oppressive environmental conditions was the most prominent factor in producing dangerous, uncompensable heat stress conditions and that the full football uniform played a smaller role in influencing Stringer's energy budget. The extreme energy budget levels that led to the fatal EHS would have been avoided according to our modeling through a combination of reduced intensity and lower clothing insulation. Finally, a long delay in providing medical treatment made the EHS fatal. These results highlight the importance of modern heat safety guidelines that provide controls on extrinsic factors, such as the adjustment of duration and intensity of training along with protective equipment modifications based on environmental conditions and the presence of an emergency action plan focused on rapid recognition and immediate on-site aggressive cooling of EHS cases.

Kuras, ER, Richardson MB, Calkins MM, Ebi KL, Hess JJ, Kintziger KW, Jagger MA, Middel A, Scott AA, Spector JT, Uejio CK, Vanos JK, Zaitchik BF, Gohlke JM, Hondula DM.  2017.  Opportunities and Challenges for Personal Heat Exposure Research. Environ Health Perspect. 125:085001.   10.1289/ehp556   Abstract

BACKGROUND: Environmental heat exposure is a public health concern. The impacts of environmental heat on mortality and morbidity at the population scale are well documented, but little is known about specific exposures that individuals experience. OBJECTIVES: The first objective of this work was to catalyze discussion of the role of personal heat exposure information in research and risk assessment. The second objective was to provide guidance regarding the operationalization of personal heat exposure research methods. DISCUSSION: We define personal heat exposure as realized contact between a person and an indoor or outdoor environment that poses a risk of increases in body core temperature and/or perceived discomfort. Personal heat exposure can be measured directly with wearable monitors or estimated indirectly through the combination of time-activity and meteorological data sets. Complementary information to understand individual-scale drivers of behavior, susceptibility, and health and comfort outcomes can be collected from additional monitors, surveys, interviews, ethnographic approaches, and additional social and health data sets. Personal exposure research can help reveal the extent of exposure misclassification that occurs when individual exposure to heat is estimated using ambient temperature measured at fixed sites and can provide insights for epidemiological risk assessment concerning extreme heat. CONCLUSIONS: Personal heat exposure research provides more valid and precise insights into how often people encounter heat conditions and when, where, to whom, and why these encounters occur. Published literature on personal heat exposure is limited to date, but existing studies point to opportunities to inform public health practice regarding extreme heat, particularly where fine-scale precision is needed to reduce health consequences of heat exposure. https://doi.org/10.1289/EHP556.

Graham, DA, Vanos JK, Kenny NA, Brown RD.  2017.  Modeling the Effects of Urban Design on Emergency Medical Response Calls during Extreme Heat Events in Toronto, Canada. International Journal of Environmental Research and Public Health. 14   10.3390/ijerph14070778   AbstractWebsite

Urban residents are at risk of health-related illness during extreme heat events but the dangers are not equal in all parts of a city. Previous studies have found a relationship between physical characteristics of neighborhoods and the number of emergency medical response (EMR) calls. We used a human energy budget model to test the effects of landscape modifications that are designed to cool the environment on the expected number of EMR calls in two neighborhoods in Toronto, Canada during extreme heat events. The cooling design strategies reduced the energy overload on people by approximately 20-30 W m(-2), resulting in an estimated 40-50% reduction in heat-related ambulance calls. These findings advance current understanding of the relationship between the urban landscape and human health and suggest straightforward design strategies to positively influence urban heat-health.

Vanos, JK, McKercher GR, Naughton K, Lochbaum M.  2017.  Schoolyard shade and sun exposure: Assessment of personal monitoring during children's physical activity. Photochemistry and Photobiology. 93:1123-1132.   10.1111/php.12721   AbstractWebsite

Childhood exposure to ultraviolet radiation ( UVR) is a major risk factor for the development of melanoma later in life. However, it is challenging to accurately determine personal outdoor exposure to UVR, specifically erythemally weighted UVR (UVEry), due to technological constraints, variable time- activity patterns, and the influence of outdoor environmental design. To address this challenge, this study utilized mobile and stationary techniques to examine the UVEry exposures of 14 children in a schoolyard in Lubbock, TX, in spring 2016. The aims of the study were to examine the influence of artificial shade on personal UVEry exposures and to assess full sun exposure ratios (ERs) within the same playground microenvironment. On average, personal wrist dosimeters worn during play in the sun measured 18% of the total onsite UVEry measured by a stationary UV pyranometer. Shade was found to significantly reduce the personal UVEry exposures by 55%, UVB280-315 nm exposures by 91%, and the overall solar radiation by 84%. Substantial benefits can be garnered through focused design of children's recreational space to utilize shade- both natural and artificial-to reduce UVR exposures during play, and to extend safe outdoor stays. Finally, although the wrist is a practical location for a dosimeter, it often underestimates full exposures, particularly during physical activity.

McKercher, GR, Salmond JA, Vanos JK.  2017.  Characteristics and applications of small, portable gaseous air pollution monitors. Environmental Pollution. 223:102-110.   10.1016/j.envpol.2016.12.045   AbstractWebsite

Background: Traditional approaches for measuring air quality based on fixed measurements are inadequate for personal exposure monitoring. To combat this issue, the use of small, portable gas-sensing air pollution monitoring technologies is increasing, with researchers and individuals employing portable and mobile methods to obtain more spatially and temporally representative air pollution data. However, many commercially available options are built for various applications and based on different technologies, assumptions, and limitations. A review of the monitor characteristics of small, gaseous monitors is missing from current scientific literature. Purpose: A state-of-the-art review of small, portable monitors that measure ambient gaseous outdoor pollutants was developed to address broad trends during the last 5-10 years, and to help future experimenters interested in studying gaseous air pollutants choose monitors appropriate for their application and sampling needs. Methods: Trends in small, portable gaseous air pollution monitor uses and technologies were first identified and discussed in a review of literature. Next, searches of online databases were performed for articles containing specific information related to performance, characteristics, and use of such monitors that measure one or more of three criteria gaseous air pollutants: ozone, nitrogen dioxide, and carbon monoxide. All data were summarized into reference tables for comparison between applications, physical features, sensing capabilities, and costs of the devices. Results: Recent portable monitoring trends are strongly related to associated applications and audiences. Fundamental research requires monitors with the best individual performance, and thus the highest cost technology. Monitor networking favors real-time capabilities and moderate cost for greater reproduction. Citizen science and crowdsourcing applications allow for lower-cost components; however important strengths and limitations for each application must be addressed or acknowledged for the given use. (C) 2016 Elsevier Ltd. All rights reserved.

Liu, Y, Zhao N, Vanos JK, Cao G.  2017.  Effects of synoptic weather on ground-level PM2.5 concentrations in the United States. Atmospheric Environment. 148:297-305.   10.1016/j.atmosenv.2016.10.052   Abstract

It is known that individual meteorological factors affect the concentrations of fine particulate matter with aerodynamic diameters ≤2.5 μm (PM2.5), yet the specific meteorological effects found in previous studies are largely inconsistent and even conflicting. This study investigates influences of daily and short term changes in synoptic weather on ground-level PM2.5 concentrations in a large geographical area (75 cities across the contiguous United States (U.S.)) by using ten-year (2001–2010) spatial synoptic classification (SSC) data. We find that in the spring, summer, and fall the presence of the tropical weather types (i.e., dry-tropical (DT) and moist-tropical (MT)) is likely to associate with significantly higher levels of PM2.5 as compared to an all-weather-type-day average, and the presence of the polar weather types (i.e., dry-polar (DP) and moist-polar (MP)) is associated with significantly lower PM2.5 concentrations. The short-term (day to day) changes in synoptic weather types in a region are also likely to lead to significant variance in PM2.5 concentrations. For example, the largest increase in PM2.5 concentration occurs with the synoptic weather type changing from DP-to-MT. Conversely, a MT-to-DP weather type change results in the largest decrease in PM2.5 concentrations. Compared to air temperature, the effects of atmospheric moisture on PM2.5 concentration tend to be subtle, demonstrating that in conjunction with moderate temperature, neither the dry nor the moist air (except moist-moderate (MM) in summer) are associated with significantly high or low PM2.5 concentrations. Finally, we find that the effects of the synoptic weather type on PM2.5 concentrations may vary for different seasons and geographical areas. These findings suggest that interactions between atmospheric factors and seasonal and/or geographical factors have considerable impacts on the PM2.5 concentrations, and therefore should be considered in addition to the SSC when conducting environment health assessments.

Solís, P, Vanos JK, Forbis RE.  2017.  The Decision-Making/Accountability Spatial Incongruence Problem for Research Linking Environmental Science and Policy. Geographical Review. 107:680-704.   10.1111/gere.12240   Abstract

Increasingly, scholars engage policy makers around fundamental, complex questions on environmental change in interdisciplinary settings. Researchers attempting to develop robust contributions to knowledge that can support policymaker understandings in this context face significant inferential challenges in dealing with the spatial dimension of their phenomenon of interest. In this paper, we extend an understanding of well-defined methodological challenges familiar to applied spatial scientists by explicitly articulating the Decision-Making/Accountability, Spatial Incongruence Problem, or DASIP. Three case studies illustrate how spatial incongruences matter to researchers who work on complex, interdisciplinary problems, while seeking to understand decision-making or policy-related phenomenon: urban heat-island mitigation research in Arizona, water transfer conflicts in Kansas, and hydraulic-fracturing debates in Texas. With such examples, we aim to evoke a deeper understanding of this problem in applied research and also inspire thinking about how scholars might innovate methods for creating knowledge about environmental change that supports spatially accountable decision making.

2016
Graham, DA, Vanos JK, Kenny NA, Brown RD.  2016.  The relationship between neighbourhood tree canopy cover and heat-related ambulance calls during extreme heat events in Toronto, Canada. Urban Forestry & Urban Greening. 20:180-186. AbstractWebsite
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Cakmak, S, Hebbern C, Cakmak JD, Vanos J.  2016.  The modifying effect of socioeconomic status on the relationship between traffic, air pollution and respiratory health in elementary schoolchildren. Journal of Environmental Management. 177:1-8.   10.1016/j.jenvman.2016.03.051   Abstract

The volume and type of traffic and exposure to air pollution have been found to be associated with respiratory health, but few studies have considered the interaction with socioeconomic status at the household level. We investigated the relationships of respiratory health related to traffic type, traffic volume, and air pollution, stratifying by socioeconomic status, based on household income and education, in 3591 schoolchildren in Windsor, Canada. Interquartile range changes in traffic exposure and pollutant levels were linked to respiratory symptoms and objective measures of lung function using generalised linear models for three levels of income and education. In 95% of the relationships among all cases, the odds ratios for reported respiratory symptoms (a decrease in measured lung function), based on an interquartile range change in traffic exposure or pollutant, were greater in the lower income/education groups than the higher, although the odds ratios were in most cases not significant. However, in up to 62% of the cases, the differences between high and low socioeconomic groups were statistically significant, thus indicating socioeconomic status (SES) as a significant effect modifier. Our findings indicate that children from lower socioeconomic households have a higher risk of specific respiratory health problems (chest congestion, wheezing) due to traffic volume and air pollution exposure.

Dixon, GP, Allen M, Gosling SN, Hondula DM, Ingole V, Lucas R, Vanos J.  2016.  Perspectives on the Synoptic Climate Classification and its Role in Interdisciplinary Research. 10:164.   10.1111/gec3.12264   Abstract

Synoptic climatology has a long history of research where weather data are aggregated and composited to gain a better understanding of atmospheric effects on non-atmospheric variables. This has resulted in an applied scientific discipline that yields methods and tools designed for applications across disciplinary boundaries. The spatial synoptic classification (SSC) is an example of such a tool that helps researchers bridge methodological gaps between disciplines, especially those studying weather effects on human health. The SSC has been applied in several multi-discipline projects, and it appears that there is ample opportunity for growth into new topical areas. Likewise, there is opportunity for the SSC network to be expanded across the globe, especially into mid-latitude locations in the Southern Hemisphere. There is some question of the utility of the SSC in tropical locations, but such decisions must be based on the actual weather data from individual locations. Despite all of the strengths and potential uses of the SSC, there are some research problems, some locations, and some datasets for which it is not suitable. Nevertheless, the success of the SSC as a cross-disciplinary method is noteworthy because it has become a catalyst for collaboration.

Vanos, JK, Middel A, McKercher G, Kuras ER, Ruddell B.  2016.  Hot playgrounds and children's health: a multiscale analysis of surface temperatures in Arizona, USA. Landscape and Urban Planning. 146:29-42. Abstract
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Cakmak, S, Hebbern C, Vanos J, Crouse DL, Burnett R.  2016.  Ozone exposure and cardiovascular-related mortality in the Canadian Census Health and Environment Cohort (CANCHEC) by spatial synoptic classification zone. Environmental Pollution. 214:589-599.: Elsevier Abstract
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2015
Hondula, DM, Balling RC, Vanos JK, Georgescu M.  2015.  Rising Temperatures, Human Health, and the Role of Adaptation. Current Climate Change Reports. 1:144-154.   10.1007/s40641-015-0016-4   Abstract

There is near consensus in the scientific community that humans will experience higher future temperatures due to the ongoing accumulation of greenhouse gases in the atmosphere. The human response to this climatic change, particularly if accompanied by a surge in extreme heat events, is a key topic being addressed by scientists across many disciplines. In this article, we review recent (2012–2015) research on human health impacts of observed and projected increases in summer temperature. We find that studies based on projected changes in climate indicate substantial increases in heat-related mortality and morbidity in the future, while observational studies based on historical climate and health records show a decrease in negative impacts during recent warming. The discrepancy between the two groups of studies generally involves how well and how quickly humans can adapt to changes in climate via physiological, behavioral, infrastructural, and/or technological adaptation, and how such adaptation is quantified.

Vanos, JK, Cakmak S, Kalkstein LS, Yagouti A.  2015.  Association of weather and air pollution interactions on daily mortality in 12 Canadian cities. Air Qual Atmos Health. 8:307-320.   10.1007/s11869-014-0266-7   Abstract

It has been well established that both meteorological attributes and air pollution concentrations affect human health outcomes. We examined all cause nonaccident mortality relationships for 28 years (1981-2008) in relation to air pollution and synoptic weather type (encompassing air mass) data in 12 Canadian cities. This study first determines the likelihood of summertime extreme air pollution events within weather types using spatial synoptic classification. Second, it examines the modifying effect of weather types on the relative risk of mortality (RR) due to daily concentrations of air pollution (nitrogen dioxide, ozone, sulfur dioxide, and particulate matter <2.5 mum). We assess both single- and two-pollutant interactions to determine dependent and independent pollutant effects using the relatively new time series technique of distributed lag nonlinear modeling (DLNM). Results display dry tropical (DT) and moist tropical plus (MT+) weathers to result in a fourfold and twofold increased likelihood, respectively, of an extreme pollution event (top 5 % of pollution concentrations throughout the 28 years) occurring. We also demonstrate statistically significant effects of single-pollutant exposure on mortality (p < 0.05) to be dependent on summer weather type, where stronger results occur in dry moderate (fair weather) and DT or MT+ weather types. The overall average single-effect RR increases due to pollutant exposure within DT and MT+ weather types are 14.9 and 11.9 %, respectively. Adjusted exposures (two-way pollutant effect estimates) generally results in decreased RR estimates, indicating that the pollutants are not independent. Adjusting for ozone significantly lowers 67 % of the single-pollutant RR estimates and reduces model variability, which demonstrates that ozone significantly controls a portion of the mortality signal from the model. Our findings demonstrate the mortality risks of air pollution exposure to differ by weather type, with increased accuracy obtained when accounting for interactive effects through adjustment for dependent pollutants using a DLNM.

Vanos, JK.  2015.  Children's health and vulnerability in outdoor microclimates: A comprehensive review. Environment international. 76:1-15.: Elsevier Abstract
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Brown, RD, Vanos JK, Kenny NA, Lenzholzer S.  2015.  Designing Urban Parks That Ameliorate the Effects of Climate Change. Landcape and Urban Planning. Abstract
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Vanos, JK, Kalkstein LS, Sanford TJ.  2015.  Detecting synoptic warming trends across the US Midwest and implications to human health and heat‐related mortality. International Journal of Climatology. 35(1):85-96.: Wiley Online Library Abstract
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Karner, A, Hondula DM, Vanos JK.  2015.  Heat exposure during non-motorized travel: Implications for transportation policy under climate change. Journal of Transport & Health. 2(4):451-459.: Elsevier Abstract
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2014
Cakmak, S, Dales R, Kauri LM, Mahmud M, Van Ryswyk K, Vanos J, Liu L, Kumarathasan P, Thomson E, Vincent R, Weichenthal S.  2014.  Metal composition of fine particulate air pollution and acute changes in cardiorespiratory physiology.   10.1016/j.envpol.2014.03.004   Abstract

BACKGROUND:Studying the physiologic effects of components of fine particulate mass (PM2.5) could contribute to a better understanding of the nature of toxicity of air pollution.OBJECTIVES:We examined the relation between acute changes in cardiovascular and respiratory function, and PM2.5-associated-metals.METHODS:Using generalized linear mixed models, daily changes in ambient PM2.5-associated metals were compared to daily changes in physiologic measures in 59 healthy subjects who spent 5-days near a steel plant and 5-days on a college campus.RESULTS:Interquartile increases in calcium, cadmium, lead, strontium, tin, vanadium and zinc were associated with statistically significant increases in heart rate of 1-3 beats per minute, increases of 1-3 mmHg in blood pressure and/or lung function decreases of up to 4% for total lung capacity.CONCLUSION:Metals contained in PM2.5 were found to be associated with acute changes in cardiovascular and respiratory physiology.

Gosling, SN, Bryce EK, Dixon GP, Gabriel KMA, Gosling EY, Hanes JM, Hondula DM, Liang L, Bustos Mac Lean PA, Muthers S, Nascimento ST, Petralli M, Vanos JK, Wanka ER.  2014.  A glossary for biometeorology. International Journal of Biometeorology. 58:277-308.   10.1007/s00484-013-0729-9   Abstract

Here we present, for the first time, a glossary of biometeorological terms. The glossary aims to address the need for a reliable source of biometeorological definitions, thereby facilitating communication and mutual understanding in this rapidly expanding field. A total of 171 terms are defined, with reference to 234 citations. It is anticipated that the glossary will be revisited in coming years, updating terms and adding new terms, as appropriate. The glossary is intended to provide a useful resource to the biometeorology community, and to this end, readers are encouraged to contact the lead author to suggest additional terms for inclusion in later versions of the glossary as a result of new and emerging developments in the field.

Vanos, JK, Hebbern C, Cakmak S.  2014.  Risk assessment for cardiovascular and respiratory mortality due to air pollution and synoptic meteorology in 10 Canadian cities. Environmental Pollution. 185:322-332.: Elsevier Abstract
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Hondula, DM, Vanos JK, Gosling SN.  2014.  The SSC: a decade of climate–health research and future directions. International journal of biometeorology. 58(2):109-120.: Springer Abstract
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2013
Vanos, JK, Cakmak S.  2013.  Changing air mass frequencies in Canada: potential links and implications for human health. Int J Biometeorol. 58:121-35.   10.1007/s00484-013-0634-2   Abstract

Many individual variables have been studied to understand climate change, yet an overall weather situation involves the consideration of many meteorological variables simultaneously at various times diurnally, seasonally, and yearly. The current study identifies a full weather situation as an air mass type using synoptic scale classification, in 30 population centres throughout Canada. Investigative analysis of long-term air mass frequency trends was completed, drawing comparisons between seasons and climate zones. We find that the changing air mass trends are highly dependent on the season and climate zone being studied, with an overall increase of moderate ('warm') air masses and decrease of polar ('cold') air masses. In the summertime, general increased moisture content is present throughout Canada, consistent with the warming air masses. The moist tropical air mass, containing the most hot and humid air, is found to increase in a statistically significant fashion in the summertime in 46% of the areas studied, which encompass six of Canada's ten largest population centres. This emphasises the need for heat adaptation and acclimatisation for a large proportion of the Canadian population. In addition, strong and significant decreases of transition/frontal passage days were found throughout Canada. This result is one of the most remarkable transition frequency results published to date due to its consistency in identifying declining trends, coinciding with research completed in the United States (US). We discuss relative results and implications to similar US air mass trend analyses, and draw upon research studies involving large-scale upper-level air flow and vortex connections to air mass changes, to small-scale meteorological and air pollution interactions. Further research is warranted to better understand such connections, and how these air masses relate to the overall and city-specific health of Canadians.