Heat is the leading cause of weather-related death in the U.S. Warmer air temperatures can also exacerbate air pollution, especially ground-level ozone. As the climate warms, heat presents both a direct and indirect threat to health and quality of life.
These interactive figures identify communities across Vermont that are most overburdened and most vulnerable to three measures of ambient temperature: Day-Night average land surface temperatures (LST), the Urban Heat Island effect, and elevated nighttime LST.
Map of Census block groups with the highest concentrations of one or more priority populations AND highest day-night average land surface temperatures (LST).
Map of Census block groups with the highest concentrations of one or more priority populations AND highest day-night average urban heat island (UHI) effects.
Map of Census block groups with the highest concentrations of one or more priority populations AND highest nighttime average land surface temperatures (LST).
These maps show communities (i.e. Census Block Groups) with high percentages of one or more priority population groups (80th percentile for the state) AND that experience the highest levels of ambient heat - measured as Land Surface Temperature (LST) - or Urban Heat Island (UHI) effects. The heat risk analysis presented here is based on Land Surface Temperatures (LST) derived from NASA’s Moderate-resolution Imaging Spectroradiometer (MODIS) satellite sensor. The three specific heat metrics highlighted here include: day-night average LST in the 80th percentile (i.e., 72.4°F or warmer), day-night average urban heat island effects in the 80th percentile (i.e., 4.6°F or warmer), and nighttime average LST in the 80th percentile (i.e., 60.2°F or warmer). These metrics are three of the six heat metrics used to calculate cumulative Heat burdens.
Priority populations represent demographic groups that environmental justice policy and research have identified as being especially vulnerable to environmental burdens as a consequence of social or economic disadvantage, physical vulnerability, or historic and persistent discrimination and inequality. These include:
Metrics of heat:
Day-Night Average LST: Day-Night Average Land Surface Temperatures (LST) represent a simple average of LST values collected during the day (11:48am - 2pm) and during the night (12am - 3:06am) over eight days, from July 28 to August 4, 2019 derived from NASA’s Moderate-resolution Imaging Spectroradiometer (MODIS) satellite sensor. Values are presented in degrees of Fahrenheit (°F).
Day-Night Average UHI: Urban Heat Island (UHI) effects refer to the difference in temperature between urban and rural areas of the state. Urban areas tend to be warmer than rural areas due to the heat-retaining qualities of concrete, asphalt and other impervious surfaces, as well as the relative absence of vegetation. The higher the UHI effect, the warmer an area is relative to the rural background. For this analysis UHI was measured as the difference between LST values across Vermont for each time period and the average LST for rural areas of the state for the same time periods. UHI is represented by the following formula: UHI effect = LST - Mean Rural LST. LST is the land surface temperature for a satellite image pixel and Mean Rural LST is the average LST for satellite image pixels in rural areas of the state.
Nighttime Average LST: Nighttime Land Surface Temperatures represent LST values collected during the night (12am - 3:06am) for the period July 28 to August 4, 2019. Values are presented in degrees of Fahrenheit (°F). High nighttime temperatures carry added significance for concerns about heat risk. Research has repeatedly shown that exposure to high nighttime temperatures over several days increases the probability of death during a heat wave in urban areas, especially for the elderly.
Population-weighted average exposures to day-night average temperatures for populations of concern in Vermont.
Population-weighted average exposures to day-night average temperatures for populations of concern in Vermont.
Population-weighted average exposures to nighttime average temperatures for populations of concern in Vermont.
These graphs show population-weighted heat exposure by group for the following temperature metrics:
Day-Night Average LST: Day-Night Average Land Surface Temperatures (LST) represent a simple average of LST values collected during the day (11:48am - 2pm) and during the night (12am - 3:06am) over eight days, from July 28 to August 4, 2019 derived from NASA’s Moderate-resolution Imaging Spectroradiometer (MODIS) satellite sensor. Values are presented in degrees of Fahrenheit (°F).
Day-Night Average UHI: Urban Heat Island (UHI) effects refer to the difference in temperature between urban and rural areas of the state. Urban areas tend to be warmer than rural areas due to the heat-retaining qualities of concrete, asphalt and other impervious surfaces, as well as the relative absence of vegetation. The higher the UHI effect, the warmer an area is relative to the rural background. For this analysis UHI was measured as the difference between LST values across Vermont for each time period and the average LST for rural areas of the state for the same time periods. UHI is represented by the following formula: UHI effect = LST - Mean Rural LST. LST is the land surface temperature for a satellite image pixel and Mean Rural LST is the average LST for satellite image pixels in rural areas of the state.
Nighttime Average LST: Nighttime Land Surface Temperatures represent LST values collected during the night (12am - 3:06am) for the period July 28 to August 4, 2019. Values are presented in degrees of Fahrenheit (°F). High nighttime temperatures carry added significance for concerns about heat risk. Research has repeatedly shown that exposure to high nighttime temperatures over several days increases the probability of death during a heat wave in urban areas, especially for the elderly.
For example, limited English speaking households (i.e., ‘Limited English HH’), reside in Census block groups that experience population-weighted average day-night land surface temperatures of over 72.5°F. Compare this to the state average (i.e., ‘Total Pop’) of 70.2°F. With regard to the Urban Heat Island (UHI) effect, all groups experience average day-night temperatures above the rural background. Limited English speaking households experience population-weighted average day-night land surface temperatures that are approximately 4.7°F warmer than the rural background.
These tables show the average day-night land surface temperatures (LST), Urban Heat Island (UHI) effects, and average nighttime LST by jurisdiction for July-August 2019. LST values are averaged across Census block groups within the jurisdiction. A rank indicates the percentage of jurisdictions that are below that value. For example, Brattleboro had a Day-Night average Land Surface Temperature (LST) of 72.5° Fahrenheit, and a Day-Night LST rank of 96.9. The latter means that Brattleboro’s average LST was higher than 96.9% of all other municipalities in the state.
Day-Night Average LST: Day-Night Average Land Surface Temperatures (LST) represent a simple average of LST values collected during the day (11:48am - 2pm) and during the night (12am - 3:06am) over eight days, from July 28 to August 4, 2019 derived from NASA’s Moderate-resolution Imaging Spectroradiometer (MODIS) satellite sensor. Values are presented in degrees of Fahrenheit (°F).
Day-Night Average UHI: Urban Heat Island (UHI) effects refer to the difference in temperature between urban and rural areas of the state. Urban areas tend to be warmer than rural areas due to the heat-retaining qualities of concrete, asphalt and other impervious surfaces, as well as the relative absence of vegetation. The higher the UHI effect, the warmer an area is relative to the rural background. For this analysis UHI was measured as the difference between LST values across Vermont for each time period and the average LST for rural areas of the state for the same time periods. UHI is represented by the following formula: UHI effect = LST - Mean Rural LST. LST is the land surface temperature for a satellite image pixel and Mean Rural LST is the average LST for satellite image pixels in rural areas of the state.
Nighttime Average LST: Nighttime Land Surface Temperatures represent LST values collected during the night (12am - 3:06am) for the period July 28 to August 4, 2019. Values are presented in degrees of Fahrenheit (°F). High nighttime temperatures carry added significance for concerns about heat risk. Research has repeatedly shown that exposure to high nighttime temperatures over several days increases the probability of death during a heat wave in urban areas, especially for the elderly.