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LST_NewEnglandPDF.Rmd
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LST_NewEnglandPDF.Rmd
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---
title: "Heat Risk in New England"
author: "Marcos Luna and Neenah Estrella-Luna"
date: "`r Sys.Date()`"
output:
bookdown::pdf_document2:
toc: true
toc_depth: 3
number_sections: true
fig_caption: yes
includes:
in_header: my_header.tex
---
```{r setup, include=FALSE}
knitr::opts_chunk$set(echo=FALSE, message=FALSE, warning=FALSE)
```
\pagebreak
# Heat risk in New England
Heat, or hot weather, is the leading weather-related cause of death in the U.S.[^NWShazards] Between 1999 and 2010, the U.S. Centers for Disease Control recorded over 8,000 heat-related deaths in the U.S.[^CDCpicture] Heat-related hospitalizations or emergency department visits are estimated to be at least 10 times the death rate.[^Samuelson2020] Heat exhaustion and heat stroke are the most serious heat-related illnesses. Exposure to excessive heat can directly or indirectly cause some illnesses and can exacerbate many preexisting conditions, such as heart and lung disease. People at greatest risk for heat-related illness include children under 5 years of age, people 65 years of age and older, people who are overweight or have existing medical conditions, such as diabetes and heart disease, people who are socially isolated, and low income individuals.[^CDCpicture]
Risk of exposure to excessive heat tends to be higher for people who work outside (e.g., agriculture, construction, and landscaping), and for those living in densely developed urban areas where there is a dearth of vegetation and an abundance of dense materials such as asphalt and concrete that absorb heat and release it more slowly (i.e., urban heat island effect). However, risk of heat-related illness or death varies within urban environments due to a variety of mitigating factors, especially age, race, and wealth.[^Williams2020] Exposure to higher temperatures than a population is accustomed to can also make people more vulnerable to heat-related illnesses and death. Although New England experiences a generally cool climate, research has shown that people in this region are actually more sensitive to elevated temperatures than those living in warmer regions of the country.[^Hondula2015]
Climate change is increasing average global temperatures, as well as the frequency, duration, and severity of extreme heat events.[^IPCCsummary] In the contiguous U.S., annual average temperatures have increased by 1.2°F (0.7°C) over the last few decades and by 1.8°F (1.0°C) relative to the beginning of the 20th century. These changes are happening more quickly in the Northeast. Average annual temperatures have increased by about 3°F (1.7°C) or more in New England since 1901. By 2050, average annual temperatures in the Northeast are projected to increase by up to 5.1°F (2.8°C) relative to the period 1975–2005, with several more days of extreme heat occurring throughout the region each year.[^4thNatlAssessment] The combination of rapidly increasing temperatures and higher sensitivity puts people in New England at especially high risk of heat-related illness and death.
The heat risk analysis presented here is based on Land Surface Temperatures (LST) derived from NASA's Moderate-resolution Imaging Spectroradiometer (MODIS) satellite sensor.[^MODIS11] Unlike ambient air temperature measured by ground-based weather stations, LST is a measure of the radiant energy (i.e., emissivity) of the ground or surface. LST values tend to be slightly higher than ambient air temperatures, but are highly correlated with air temperatures. Abundant research has shown that satellite-derived LST is an acceptable proxy for air temperature.[^Kloog2014] Moreover, while weather stations are sparsely and unevenly distributed, satellite-derived LST has the advantage of providing an unbroken and continuous snapshot of temperature at high resolution across the region at any given moment.
The MODIS data used here covers average day and night LST for an 8-day period from July 28 to August 4, 2019 for the entire region. That week constituted the conclusion of a historically warm July for New England This data originates at 1km spatial resolution and was extracted to average temperatures at each Census Block Group separately for day-night averages, daytime, nighttime, and urban heat island effects. LST data was validated against ground weather station data for the same time periods (see Appendix A).
```{r dataLST, include=FALSE}
library(tmap)
library(tidyverse)
library(sf)
library(tmaptools)
library(maptools)
library(ggcorrplot)
library(spdep)
library(rgdal)
library(gdalUtils)
library(raster)
library(tigris)
options(tigris_use_cache = TRUE, tigris_class = "sf")
library(lwgeom)
library(OpenStreetMap)
# load basic layers
load("DATA/ne_layers.rds")
# # create OSM basemap. see help on openmap for type options.
# ne_bmap <- ne_states_sf_cb %>%
# st_transform(., crs = 4326) %>%
# st_bbox(.) %>%
# read_osm(., type = "stamen-watercolor")
#
# # map basemap
# tm_shape(ne_bmap) + tm_rgb() + tm_shape(ne_states_sf_cb) + tm_borders()
# # STEPS FOR PROCESSING LST DATA
# # MODIS data acquired through USGS EarthExplorer portal. https://earthexplorer.usgs.gov/
# # read in HDF (Hierarchical Data Format) scientific data sets (SDSs) for MODIS from Terra satellite
# sdsJuly282019h12Terra <- get_subdatasets("DATA/LST/MODISJulyAug2019/MOD11A2.A2019209.h12v04.006.2019218045630.hdf")
# sdsJuly282019h13Terra <- get_subdatasets("DATA/LST/MODISJulyAug2019/MOD11A2.A2019209.h13v04.006.2019218045706.hdf")
#
# # sdsJuly282019h12 <- get_subdatasets("LST/MODIS8dayLST1km/2345441438/MOD11A2_A2019209_h12v04_006_2019218045630_HEGOUT.hdf")
# # sdsJuly282019h13 <- get_subdatasets("LST/MODIS8dayLST1km/2345441418/MOD11A2_A2019209_h13v04_006_2019218045706_HEGOUT.hdf")
#
# # read in HDF (Hierarchical Data Format) scientific data sets (SDSs) for MODIS from Aqua satellite
# sdsJuly282019h12Aqua <- get_subdatasets("DATA/LST/MODISJulyAug2019/MYD11A2.A2019209.h12v04.006.2019218030935.hdf")
# sdsJuly282019h13Aqua <- get_subdatasets("DATA/LST/MODISJulyAug2019/MYD11A2.A2019209.h13v04.006.2019218033834.hdf")
#
# # retrieve desired data from MODIS Terra (late morning 10:06am - 12:18pm and early evening 8:42pm - 11pm)
# LSTdayJuly282019h12Terra <- readGDAL(sdsJuly282019h12Terra[1])
# daytimeH12Terra <- readGDAL(sdsJuly282019h12Terra[3])
# LSTnightJuly282019h12Terra <- readGDAL(sdsJuly282019h12Terra[5])
# nighttimeH12Terra <- readGDAL(sdsJuly282019h12Terra[7])
# LSTdayJuly282019h13Terra <- readGDAL(sdsJuly282019h13Terra[1])
# daytimeH13Terra <- readGDAL(sdsJuly282019h13Terra[3])
# LSTnightJuly282019h13Terra <- readGDAL(sdsJuly282019h13Terra[5])
# nighttimeH13Terra <- readGDAL(sdsJuly282019h13Terra[7])
#
# # retrieve desired data sets from MODIS Aqua (early afternoon 11:48am - 2pm and later evening 12am - 3:06am)
# LSTdayJuly282019h12Aqua <- readGDAL(sdsJuly282019h12Aqua[1])
# daytimeH12Aqua <- readGDAL(sdsJuly282019h12Aqua[3])
# LSTnightJuly282019h12Aqua <- readGDAL(sdsJuly282019h12Aqua[5])
# nighttimeH12Aqua <- readGDAL(sdsJuly282019h12Aqua[7])
# LSTdayJuly282019h13Aqua <- readGDAL(sdsJuly282019h13Aqua[1])
# daytimeH13Aqua <- readGDAL(sdsJuly282019h13Aqua[3])
# LSTnightJuly282019h13Aqua <- readGDAL(sdsJuly282019h13Aqua[5])
# nighttimeH13Aqua <- readGDAL(sdsJuly282019h13Aqua[7])
#
# # assign to raster image to manipulate data for visualization and analysis and convert from Kelvin to Fahrenheit
# LSTdayJuly282019h12r <- raster(LSTdayJuly282019h12Aqua)*(9/5) - 459.67
# LSTnightJuly282019h12r <- raster(LSTnightJuly282019h12Aqua)*(9/5) - 459.67
# LSTdayJuly282019h13r <- raster(LSTdayJuly282019h13Aqua)*(9/5) - 459.67
# LSTnightJuly282019h13r <- raster(LSTnightJuly282019h13Aqua)*(9/5) - 459.67
#
# # # If origins are different, need to adjust tolerance to mosaic
# # origin(LSTdayJuly282019h12r)
# # origin(LSTdayJuly282019h13r)
#
# # mosic rasters
# # create LST day mosaic raster
# LSTdayJuly2019r <- mosaic(LSTdayJuly282019h12r,LSTdayJuly282019h13r,
# fun=mean, tolerance = 1)
#
# # create LST night mosaic raster
# LSTnightJuly2019r <- mosaic(LSTnightJuly282019h12r,LSTnightJuly282019h13r,
# fun=mean, tolerance = 1)
#
# # create average of day and night
# LSTavgJuly2019r <- (LSTdayJuly2019r + LSTnightJuly2019r)/2
#
# # create average day - night difference
# LSTDayNighDiffJuly2019r <- LSTdayJuly2019r - LSTnightJuly2019r
#
# # clean up
# rm(list = ls(pattern = "h12|h13"))
#
# # Crop LST to New England
# # define new projection
# newproj <- st_crs(ne_blkgrp_sf)[[2]]
#
# LSTavgJuly2019r_ne <- LSTavgJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_states_sf_cb) %>%
# mask(., ne_states_sf_cb)
#
# LSTdayJuly2019r_ne <- LSTdayJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_states_sf_cb) %>%
# mask(., ne_states_sf_cb)
#
# LSTnightJuly2019r_ne <- LSTnightJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_states_sf_cb) %>%
# mask(., ne_states_sf_cb)
#
# LSTDayNighDiffJuly2019r_ne <- LSTDayNighDiffJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_states_sf_cb) %>%
# mask(., ne_states_sf_cb)
#
# # download Census-designated urban areas to contrast with rural areas
# us_urban_sf <- urban_areas(cb = TRUE)
#
# # create urban area polygon for New England
# ne_urban_sf <- us_urban_sf %>%
# st_centroid(.) %>%
# st_join(., ne_states_sf_cb, join = st_within, left = FALSE) %>%
# as.data.frame() %>%
# dplyr::select(GEOID10) %>%
# inner_join(us_urban_sf,.,by="GEOID10") %>%
# group_by() %>%
# summarize()
#
# # create rural area polygon
# ne_rural_sf <- ne_states_sf_cb %>%
# group_by() %>%
# summarize() %>%
# st_difference(., ne_urban_sf) %>%
# st_make_valid()
#
# # # select blkgrps that do not intersect wtih urban polygons - rural blkgrps
# # ne_blkgrpLST_rural <- st_disjoint(ne_blkgrp_sf,
# # ne_urban_sf,sparse = FALSE) %>%
# # apply(., 1, all) %>% # convert dense matrix to logical vector
# # ne_blkgrpLST_sf[.,] # subset blkgrps where there is NO intersection
# #
# # # select blkgrps that intersect with urban polygons - urban blkgrps
# # ne_blkgrpLST_urban <- st_intersects(ne_blkgrp_sf,
# # ne_urban_sf,sparse = FALSE) %>%
# # apply(., 1, any) %>% # convert dense matrix to logical vector
# # ne_blkgrpLST_sf[.,] # subset blkgrps where there is ANY intersection
# #
# # ne_blkgrp_urban_simple <- ne_blkgrpLST_urban %>%
# # group_by() %>%
# # summarize()
# #
# # ne_blkgrp_rural_simple <- ne_blkgrpLST_rural %>%
# # group_by() %>%
# # summarize()
#
# # crop LST to urban
# LSTavgJuly2019r_neUrban <- LSTavgJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_urban_sf) %>%
# mask(., ne_urban_sf)
#
# LSTdayJuly2019r_neUrban <- LSTdayJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_urban_sf) %>%
# mask(., ne_urban_sf)
#
# LSTnightJuly2019r_neUrban <- LSTnightJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_urban_sf) %>%
# mask(., ne_urban_sf)
#
# LSTDayNighDiffJuly2019r_neUrban <- LSTDayNighDiffJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_urban_sf) %>%
# mask(., ne_urban_sf)
#
# # crop LST to rural
# LSTavgJuly2019r_neRural <- LSTavgJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_rural_sf) %>%
# mask(., ne_rural_sf)
#
# LSTdayJuly2019r_neRural <- LSTdayJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_rural_sf) %>%
# mask(., ne_rural_sf)
#
# LSTnightJuly2019r_neRural <- LSTnightJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_rural_sf) %>%
# mask(., ne_rural_sf)
#
# LSTDayNighDiffJuly2019r_neRural <- LSTDayNighDiffJuly2019r %>%
# projectRaster(., crs = newproj) %>%
# crop(., ne_rural_sf) %>%
# mask(., ne_rural_sf)
#
# # Identify stats to compute thresholds
# LSTavgJuly2019mean <- cellStats(x = LSTavgJuly2019r_ne, stat = "mean")
# LSTavgJuly2019Urbanmean <- cellStats(x = LSTavgJuly2019r_neUrban, stat = "mean")
# LSTavgJuly2019Ruralmean <- cellStats(x = LSTavgJuly2019r_neRural, stat = "mean")
# LSTdayJuly2019mean <- cellStats(x = LSTdayJuly2019r_ne, stat = "mean")
# LSTdayJuly2019Urbanmean <- cellStats(x = LSTdayJuly2019r_neUrban, stat = "mean")
# LSTdayJuly2019Ruralmean <- cellStats(x = LSTdayJuly2019r_neRural, stat = "mean")
# LSTnightJuly2019mean <- cellStats(x = LSTnightJuly2019r_ne, stat = "mean")
# LSTnightJuly2019Urbanmean <- cellStats(x = LSTnightJuly2019r_neUrban, stat = "mean")
# LSTnightJuly2019Ruralmean <- cellStats(x = LSTnightJuly2019r_neRural, stat = "mean")
# LSTavgJuly2019sd <- cellStats(x = LSTavgJuly2019r_ne, stat = "sd")
# LSTavgJuly2019Urbansd <- cellStats(x = LSTavgJuly2019r_neUrban, stat = "sd")
# LSTavgJuly2019Ruralsd <- cellStats(x = LSTavgJuly2019r_neRural, stat = "sd")
# LSTdayJuly2019sd <- cellStats(x = LSTdayJuly2019r_ne, stat = "sd")
# LSTdayJuly2019Urbansd <- cellStats(x = LSTdayJuly2019r_neUrban, stat = "sd")
# LSTdayJuly2019Ruralsd <- cellStats(x = LSTdayJuly2019r_neRural, stat = "sd")
# LSTnightJuly2019sd <- cellStats(x = LSTnightJuly2019r_ne, stat = "sd")
# LSTnightJuly2019Urbansd <- cellStats(x = LSTnightJuly2019r_neUrban, stat = "sd")
# LSTnightJuly2019Ruralsd <- cellStats(x = LSTnightJuly2019r_neRural, stat = "sd")
#
# # Create rasters of cells exceeding threshold
# LSTavgJulyHI <- LSTavgJuly2019r_ne >
# (LSTavgJuly2019mean + LSTavgJuly2019sd * 3)
# LSTdayJulyHI <- LSTdayJuly2019r_ne >
# (LSTdayJuly2019mean + LSTdayJuly2019sd * 3)
# LSTnightJulyHI <- LSTnightJuly2019r_ne >
# (LSTnightJuly2019mean + LSTnightJuly2019sd * 3)
#
# # Extract raster values to block groups
# # check for empty geometries
# any(is.na(st_dimension(ne_blkgrp_sf)))
# # identiy empty geometries
# empty_geo <- st_is_empty(ne_blkgrp_sf)
# # filter out empty geometries
# ne_blkgrp_sf <- ne_blkgrp_sf[!empty_geo,]
# # clean up
# rm(empty_geo)
#
# # Extract mean LST values within each block group to a df
# meanLSTavg_df <- ne_blkgrp_sf %>%
# dplyr::select(GEOID) %>%
# as_Spatial() %>%
# extract(LSTavgJuly2019r_ne, .,
# fun=mean, sp=TRUE, na.rm=TRUE, small=TRUE) %>%
# as.data.frame() %>%
# rename(meanAvgLST = layer)
#
# meanLSTday_df <- ne_blkgrp_sf %>%
# dplyr::select(GEOID) %>%
# as_Spatial() %>%
# extract(LSTdayJuly2019r_ne, .,
# fun=mean, sp=TRUE, na.rm=TRUE, small=TRUE) %>%
# as.data.frame() %>%
# rename(meanDayLST = layer)
#
# meanLSTnight_df <- ne_blkgrp_sf %>%
# dplyr::select(GEOID) %>%
# as_Spatial() %>%
# extract(LSTnightJuly2019r_ne, .,
# fun=mean, sp=TRUE, na.rm=TRUE, small=TRUE) %>%
# as.data.frame() %>%
# rename(meanNightLST = layer)
#
# meanLSTDayNightDiff_df <- ne_blkgrp_sf %>%
# dplyr::select(GEOID) %>%
# as_Spatial() %>%
# extract(LSTDayNighDiffJuly2019r_ne,.,
# fun=mean, sp=TRUE, na.rm=TRUE, small=TRUE) %>%
# as.data.frame() %>%
# rename(meanDayNightDiffLST = layer)
#
# # # Extract mean LST value for rural areas in order to compute urban heat island
# # meanLSTavgRural_df <- ne_blkgrp_rural_simple %>%
# # as_Spatial() %>%
# # extract(LSTavgJuly2019r_ne, .,
# # fun=mean, sp=TRUE, na.rm=TRUE, small=TRUE) %>%
# # as.data.frame() %>%
# # rename(meanAvgLSTrural = layer)
#
# # Join LST statistics to block groups
# ne_blkgrpLST_sf <- ne_blkgrp_sf %>%
# left_join(., meanLSTavg_df, by = "GEOID") %>%
# left_join(., meanLSTday_df, by = "GEOID") %>%
# left_join(., meanLSTnight_df, by = "GEOID") %>%
# left_join(., meanLSTDayNightDiff_df, by = "GEOID") %>%
# mutate(UHI24avg = meanAvgLST - LSTavgJuly2019Ruralmean,
# UHIDay = meanDayLST - LSTdayJuly2019Ruralmean,
# UHINight = meanNightLST - LSTnightJuly2019Ruralmean)
#
# save(ne_blkgrpLST_sf, ne_urban_sf, ne_rural_sf, file = "DATA/LST/ne_blkgrpLST_sf.rds")
#
# load previously processed LST data
load("DATA/LST/ne_blkgrpLST_sf.rds")
# Calculate percentiles for pops of concern and temperature and create ranks for comparison
ne_blkgrpLST_sf <- ne_blkgrpLST_sf %>%
mutate(pctile24hrLST = percent_rank(meanAvgLST),
rank24hrLST = case_when(
pctile24hrLST < 0.2 ~ 1,
pctile24hrLST >= 0.2 & pctile24hrLST < 0.4 ~ 2,
pctile24hrLST >= 0.4 & pctile24hrLST < 0.6 ~ 3,
pctile24hrLST >= 0.6 & pctile24hrLST < 0.8 ~ 4,
pctile24hrLST >= 0.8 ~ 5),
pctileDayLST = percent_rank(meanDayLST),
rankDayLST = case_when(
pctileDayLST < 0.2 ~ 1,
pctileDayLST >= 0.2 & pctileDayLST < 0.4 ~ 2,
pctileDayLST >= 0.4 & pctileDayLST < 0.6 ~ 3,
pctileDayLST >= 0.6 & pctileDayLST < 0.8 ~ 4,
pctileDayLST >= 0.8 ~ 5),
pctileNightLST = percent_rank(meanNightLST),
rankNightLST = case_when(
pctileNightLST < 0.2 ~ 1,
pctileNightLST >= 0.2 & pctileNightLST < 0.4 ~ 2,
pctileNightLST >= 0.4 & pctileNightLST < 0.6 ~ 3,
pctileNightLST >= 0.6 & pctileNightLST < 0.8 ~ 4,
pctileNightLST >= 0.8 ~ 5),
pctileMinority = percent_rank(minority_pctE),
rankMinority = case_when(
pctileMinority < 0.2 ~ 1,
pctileMinority >= 0.2 & pctileMinority < 0.4 ~ 2,
pctileMinority >= 0.4 & pctileMinority < 0.6 ~ 3,
pctileMinority >= 0.6 & pctileMinority < 0.8 ~ 4,
pctileMinority >= 0.8 ~ 5),
LST24MinorScore = (rank24hrLST + rankMinority)/2,
LSTDayMinorScore = (rankDayLST + rankMinority)/2,
LSTNightMinorScore = (rankNightLST + rankMinority)/2,
pctileEngLang = percent_rank(eng_limit_pctE),
rankEngLang = case_when(
pctileEngLang < 0.2 ~ 1,
pctileEngLang >= 0.2 & pctileEngLang < 0.4 ~ 2,
pctileEngLang >= 0.4 & pctileEngLang < 0.6 ~ 3,
pctileEngLang >= 0.6 & pctileEngLang < 0.8 ~ 4,
pctileEngLang >= 0.8 ~ 5),
LST24EngLangScore = (rank24hrLST + rankEngLang)/2,
LSTDayEngLangScore = (rankDayLST + rankEngLang)/2,
LSTNightEngLangScore = (rankNightLST + rankEngLang)/2,
pctileLowInc = percent_rank(pct2povE),
rankLowInc = case_when(
pctileLowInc < 0.2 ~ 1,
pctileLowInc >= 0.2 & pctileLowInc < 0.4 ~ 2,
pctileLowInc >= 0.4 & pctileLowInc < 0.6 ~ 3,
pctileLowInc >= 0.6 & pctileLowInc < 0.8 ~ 4,
pctileLowInc >= 0.8 ~ 5),
LST24LowIncScore = (rank24hrLST + rankLowInc)/2,
LSTDayLowIncScore = (rankDayLST + rankLowInc)/2,
LSTNightLowIncScore = (rankNightLST + rankLowInc)/2,
pctileNoHSDip = percent_rank(pct_lthsE),
rankNoHSDip = case_when(
pctileNoHSDip < 0.2 ~ 1,
pctileNoHSDip >= 0.2 & pctileNoHSDip < 0.4 ~ 2,
pctileNoHSDip >= 0.4 & pctileNoHSDip < 0.6 ~ 3,
pctileNoHSDip >= 0.6 & pctileNoHSDip < 0.8 ~ 4,
pctileNoHSDip >= 0.8 ~ 5),
LST24NoHSDipScore = (rank24hrLST + rankNoHSDip)/2,
LSTDayNoHSDipScore = (rankDayLST + rankNoHSDip)/2,
LSTNightNoHSDipScore = (rankNightLST + rankNoHSDip)/2,
pctileUnder5 = percent_rank(pct_under5E),
rankUnder5 = case_when(
pctileUnder5 < 0.2 ~ 1,
pctileUnder5 >= 0.2 & pctileUnder5 < 0.4 ~ 2,
pctileUnder5 >= 0.4 & pctileUnder5 < 0.6 ~ 3,
pctileUnder5 >= 0.6 & pctileUnder5 < 0.8 ~ 4,
pctileUnder5 >= 0.8 ~ 5),
LST24Under5Score = (rank24hrLST + rankUnder5)/2,
LSTDayUnder5Score = (rankDayLST + rankUnder5)/2,
LSTNightUnder5Score = (rankNightLST + rankUnder5)/2,
pctileOver64 = percent_rank(pct_over64E),
rankOver64 = case_when(
pctileOver64 < 0.2 ~ 1,
pctileOver64 >= 0.2 & pctileOver64 < 0.4 ~ 2,
pctileOver64 >= 0.4 & pctileOver64 < 0.6 ~ 3,
pctileOver64 >= 0.6 & pctileOver64 < 0.8 ~ 4,
pctileOver64 >= 0.8 ~ 5),
LST24Over64Score = (rank24hrLST + rankOver64)/2,
LSTDayOver64Score = (rankDayLST + rankOver64)/2,
LSTNightOver64Score = (rankNightLST + rankOver64)/2
)
# Calculate totals of populations of concern for use in computing percentages in later tables
statepopsdf <- ne_blkgrpLST_sf %>%
as.data.frame() %>%
group_by(STATE) %>%
summarize(TotalLEH = sum(eng_limitE, na.rm = TRUE),
TotalMin = sum(minorityE, na.rm = TRUE),
TotalLowInc = sum(num2povE, na.rm = TRUE),
TotalNoHS = sum(lthsE, na.rm = TRUE),
TotalOver64 = sum(over64E, na.rm = TRUE),
TotalUnder5 = sum(under5E, na.rm = TRUE))
```
## Day-Night Average Land Surface Temperatures
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. The day-night average for the entire region that week was `r round(mean(ne_blkgrpLST_sf$meanAvgLST,na.rm=TRUE),1)`°F. These day-night average temperatures varied significantly across New England, with highest temperatures apparent in the most urbanized areas of the region. This is particularly apparent along the I-95 corridor from Stamford, Connecticut to New Haven, and along the I-91 corridor from New Haven through Hartford to Springfield, Massachusetts. Higher temperatures are also apparent around greater Providence, Rhode Island, and the greater Boston region, reaching into southern New Hampshire (see Figure \@ref(fig:mapLSTavgNE)).
```{r mapLSTavgNE, fig.align = "center", fig.cap="Map of July-Aug 2019 Day-Night Average Land Surface Temperatures (LST) across New England at Census Block Group level.", strip.white=TRUE}
# Map of average LST across New England
m <- tm_shape(ne_blkgrpLST_sf, unit = "mi") +
tm_fill("meanAvgLST", style = "quantile", palette = "Oranges",
title = expression("Temperature " ( degree*F)),
legend.hist = FALSE,
colorNA = NULL,
textNA = NULL,
legend.format=list(list(digits=1)),
legend.is.portrait = TRUE) +
tm_shape(ne_states_sf_cb) + tm_borders(alpha = 0.4, lwd = 0.5) +
tm_text("STUSPS", size = 0.7, remove.overlap = TRUE, col = "gray") +
tm_shape(ne_towns_sf_pts) + tm_dots() +
tm_text("NAME", size = 0.5, col = "black", xmod = 0.7, ymod = 0.2) +
tm_scale_bar(breaks = c(0, 50, 100), text.size = 0.5,
position = c(0.6,0.005)) +
tm_layout(title = "Day-Night Average\nLand Surface\nTemperatures\nJuly-Aug 2019",
frame = FALSE, main.title.size = 0.8,
legend.outside = TRUE,
legend.title.size = 0.8,
legend.outside.position = c("right", "top"),
legend.hist.width = 0.9)
tmap_save(m, "DATA/LST/ne_24hrLST.png",
height = 8, width = 8, units = "in", dpi = 600)
knitr::include_graphics("DATA/LST/ne_24hrLST.png")
```
```{r LST24outliers, include=FALSE}
# download municipal polygons
nh_towns_sf <- county_subdivisions("NH") %>%
dplyr::select(NAME) %>%
st_transform(., crs = st_crs(ne_blkgrpLST_sf))
me_towns_sf <- county_subdivisions("ME") %>%
dplyr::select(NAME) %>%
st_transform(., crs = st_crs(ne_blkgrpLST_sf))
# Identify municipalities with high heat outliers in New Hampshire and Maine
nh_LST24outliers <- ne_blkgrpLST_sf %>%
filter(STATE == "New Hampshire") %>%
filter(meanAvgLST == max(meanAvgLST, na.rm = TRUE)) %>%
st_centroid(.) %>%
st_intersection(nh_towns_sf,.) %>%
filter(row_number() == 1) %>%
pull(NAME)
me_LST24outliers <- ne_blkgrpLST_sf %>%
filter(STATE == "Maine") %>%
filter(meanAvgLST == max(meanAvgLST, na.rm = TRUE)) %>%
st_centroid(.) %>%
st_intersection(me_towns_sf,.) %>%
filter(row_number() == 1) %>%
pull(NAME)
```
Rhode Island, Massachusetts, and Connecticut are the warmest states in New England and exhibit significantly different median day-night average temperatures, although the highest temperatures are very similar (see Figure \@ref(fig:boxplotLSTavgNE)). By contrast, Vermont, Maine, and New Hampshire are significantly cooler overall, with Vermont exhibiting the coolest day-night average temperatures in New England. Although New Hampshire and Maine are cooler on average, some Block Groups show much higher temperatures, comparable to the highest temperatures in southern New England. This is the case in `r nh_LST24outliers`, New Hampshire and `r me_LST24outliers`, Maine.
```{r boxplotLSTavgNE, fig.align = "center", fig.cap="Boxplot of July-Aug 2019 day-night average Land Surface Temperatures (LST) across New England at Census Block Group level."}
# boxplot of PM2.5 by state for 2016
ne_blkgrpLST_sf %>%
as.data.frame() %>%
drop_na(meanAvgLST) %>%
ggplot(aes(x = reorder(STATE, meanAvgLST, FUN = "median", .desc = TRUE),
y = meanAvgLST, fill = STATE)) +
geom_boxplot(notch = TRUE) +
ggtitle("Day-Night Average Land Surface Temperatures July-Aug 2019") +
theme_minimal() +
scale_y_continuous(labels = function(x) paste0(x, "°")) +
theme(legend.position = "none", axis.text=element_text(size=8)) +
xlab(NULL) +
ylab("Temperature (°F)") +
coord_flip()
```
### Day-Night Average Urban Heat Island Effect
The urban heat island (UHI) effect is a phenomenon in which temperatures in urban areas tend to be higher than surrounding non-urban or rural areas. These elevated urban air temperatures are a consequence of the high density of buildings, roads, and other impervious infrastructure in urban areas that absorb heat and release it more slowly. The UHI effect is compounded by the relative absence of vegetation which would otherwise moderate temperatures through evaporative cooling.[^Zhou2019] Higher summer temperatures due to UHI increase the risk of heat-related illnesses, result in increased energy use for air conditioning, and exacerbate air pollution, especially ground-level ozone. As the climate warms, UHI are likely to exacerbate both temperature and air pollution risks.
The UHI effect analyzed here is defined as the difference in temperature between urbanized areas and rural areas in New England.[^urban] Specifically, the average temperature of the rural areas of New England is subtracted from the average temperatures of each Census Block Group. The resulting value shows how much warmer or cooler each Census Block Group is when compared to the rural background reference. Positive values indicate that a Census Block Group is warmer than the rural background average and may be experiencing the UHI effect. The larger the value, the stronger the effect.
The UHI effect for day-night average temperatures in New England are most pronounced in the inner core of urbanized areas (see Figure \@ref(fig:mapUHIavgNE)), particularly around Hartford, Connecticut, Providence, Rhode Island, and Boston, Massachusetts. Temperatures in these areas are up to `r round(max(ne_blkgrpLST_sf$UHI24avg, na.rm = TRUE),1)`° warmer than the rural background average. By contrast, most of Vermont, northern New Hampshire, and northwestern Maine are cooler than rural background average.
```{r mapUHIavgNE, fig.align = "center", fig.cap="Map of July-Aug 2019 day-night average Urban Heat Island (UHI) effect across New England at Census Block Group level. UHI is the difference between Block Group average temperature and average temperature of rural areas.", strip.white=TRUE}
# Map of average LST UHI across New England
m <- tm_shape(ne_blkgrpLST_sf, unit = "mi") +
tm_fill("UHI24avg", palette = "-RdYlGn", midpoint = 0,
legend.reverse = TRUE,
title = expression("Temperature " ( degree*F)),
legend.hist = FALSE,
colorNA = NULL,
textNA = NULL,
legend.format=list(list(digits=1)),
legend.is.portrait = TRUE) +
tm_shape(ne_states_sf_cb) + tm_borders(alpha = 0.4, lwd = 0.5) +
tm_text("STUSPS", size = 0.7, remove.overlap = TRUE, col = "gray") +
tm_shape(ne_towns_sf_pts) + tm_dots() +
tm_text("NAME", size = 0.5, col = "black", xmod = 0.7, ymod = 0.2) +
tm_scale_bar(breaks = c(0, 50, 100), text.size = 0.5,
position = c(0.6,0.005)) +
tm_layout(title = "Day-Night Average\nUrban Heat Island\nJuly-Aug 2019",
frame = FALSE, main.title.size = 0.8,
legend.outside = TRUE,
legend.title.size = 0.8,
legend.outside.position = c("right", "top"),
legend.hist.width = 0.9)
tmap_save(m, "DATA/LST/ne_24hrUHI.png",
height = 8, width = 8, units = "in", dpi = 600)
knitr::include_graphics("DATA/LST/ne_24hrUHI.png")
```
Rhode Island, Massachusetts, and Connecticut exhibit median UHI effects that are significantly different from one another, although the highest values are similar with respect to the UHI effect (see Figure \@ref(fig:boxplotUHIavgNE)). In these states, median UHI effects range from `r ne_blkgrpLST_sf %>% as.data.frame() %>% filter(STATE == "Connecticut") %>% summarize(round(median(UHI24avg, na.rm = TRUE),1)) %>% pull()`° to `r ne_blkgrpLST_sf %>% as.data.frame() %>% filter(STATE == "Rhode Island") %>% summarize(round(median(UHI24avg, na.rm = TRUE),1)) %>% pull()`° above the rural background. Northern New England states show significantly lower UHI effect values. Vermont's median value is only slightly above 0°, indicating little difference from the rural background temperature.
```{r boxplotUHIavgNE, fig.align = "center", fig.cap="Boxplot of July-Aug 2019 day-night average Urban Heat Island (UHI) across New England at Census Block Group level. UHI is the difference between Block Group average temperature and average temperature of rural areas."}
# boxplot of PM2.5 by state for 2016
ne_blkgrpLST_sf %>%
as.data.frame() %>%
drop_na(UHI24avg) %>%
ggplot(aes(x = reorder(STATE, UHI24avg, FUN = "median", .desc = TRUE),
y = UHI24avg, fill = STATE)) +
geom_boxplot(notch = TRUE) +
ggtitle("Day-Night Average UHI July-Aug 2019") +
theme_minimal() +
scale_y_continuous(labels = function(x) paste0(x, "°")) +
theme(legend.position = "none", axis.text=element_text(size=8)) +
xlab(NULL) +
ylab("Temperature (°F)") +
coord_flip()
```
### Day-Night Average Land Surface Temperatures and Populations of Concern
```{r LST24hrTempPop, include=FALSE}
# Pop Weighted avg of 24hr LST exposure for all Groups in New England relative to NE average
LST24hrPop <- ne_blkgrpLST_sf %>%
as.data.frame() %>%
# filter(STATE == "Massachusetts") %>%
dplyr::select(totalpopE,
nhwhitepopE,
minorityE,
nhblackpopE,
nhamerindpopE,
nhasianpopE,
nhnativhpopE,
nhotherpopE,
nh2morepopE,
hisppopE,
povknownE,
num2povE,
eng_hhE,
eng_limitE,
age25upE,
lthsE,
allAgesE,
under5E,
over64E,
meanAvgLST) %>%
gather(key = Group, value = Pop, totalpopE:over64E) %>%
group_by(Group) %>%
summarize(LST24hrwMean = weighted.mean(x = meanAvgLST, w = Pop, na.rm = TRUE),
LST24hrMean = mean(meanAvgLST, na.rm = TRUE)) %>%
filter(Group %in% c("minorityE","eng_limitE","num2povE","lthsE","under5E","over64E")) %>%
mutate(Group = case_when(
Group == "minorityE" ~ "Minority",
Group == "eng_limitE" ~ "Limited English HH",
Group == "num2povE" ~ "Low Income",
Group == "lthsE" ~ "No HS Dip",
Group == "under5E" ~ "Under 5",
Group == "over64E" ~ "Over 64"))
# Pop Weighted avg of LST24hr for all Groups in New England relative to NE average
LST24hrPopTab <- ne_blkgrpLST_sf %>%
as.data.frame() %>%
# filter(STATE == "Massachusetts") %>%
dplyr::select(totalpopE,
nhwhitepopE,
minorityE,
nhblackpopE,
nhamerindpopE,
nhasianpopE,
nhnativhpopE,
nhotherpopE,
nh2morepopE,
hisppopE,
povknownE,
num2povE,
eng_hhE,
eng_limitE,
age25upE,
lthsE,
allAgesE,
under5E,
over64E,
meanAvgLST) %>%
gather(key = Group, value = Pop, totalpopE:over64E) %>%
group_by(Group) %>%
summarize(LST24hrwMean = weighted.mean(x = meanAvgLST, w = Pop, na.rm = TRUE),
LST24hrMean = mean(meanAvgLST, na.rm = TRUE)) %>%
spread(key = Group, value = LST24hrwMean) %>%
transmute(Minority = (minorityE/LST24hrMean - 1)*100,
#Minority_NHW = (minorityE/nhwhitepopE - 1)*100,
`Limited English HH` = (eng_limitE/LST24hrMean - 1)*100,
`Low Income` = (num2povE/LST24hrMean - 1)*100,
`No HS Dip` = (lthsE/LST24hrMean - 1)*100,
`Under 5` = (under5E/LST24hrMean - 1)*100,
`Over 64` = (over64E/LST24hrMean - 1)*100) %>%
gather(key = Group, value = Pct) %>%
left_join(x = LST24hrPop, y = ., by = "Group") %>%
mutate(Difference = LST24hrwMean - LST24hrMean) %>%
transmute(Group = Group,
LST24hrwMean = paste0(round(LST24hrwMean,2),"°"),
Difference = if_else(Difference > 0,
paste0("+",round(Difference,2),"°"),
paste0(round(Difference,2),"°")),
Pct = if_else(Pct > 0, paste0("+",round(Pct,2),"%"),
paste0(round(Pct,2),"%")))
```
In addition to variations in the general geography of Land Surface Temperatures (LST), temperature exposure also varies demographically. Figure \@ref(fig:plotLST24hrTempPopAvgNE) and Table \@ref(tab:tabLST24hrPopAvgNE) show population-weighted exposures for populations of concern relative to the day-night average LST for the region. For example, limited English speaking households in New England were exposed to a population-weighted day-night average LST of `r round(max(LST24hrPop$LST24hrwMean),1)`°, approximately `r round(max(LST24hrPop$LST24hrwMean) - max(LST24hrPop$LST24hrMean),1)`° (`r LST24hrPopTab[1,4]`) above the regional day-night average LST. Similarly, minorities were exposed to a population-weighted day-night average LST of `r LST24hrPop %>% filter(Group == "Minority") %>% summarize(round(max(LST24hrwMean),1)) %>% pull()`°, over `r round(LST24hrPop %>% filter(Group == "Minority") %>% summarize(max(LST24hrwMean)) %>% pull() - max(LST24hrPop$LST24hrMean),1)`° (`r LST24hrPopTab[3,4]`) above the regional day-night average LST. By contrast, persons over age 64 were, on average, exposed to population-weighted day-night average LSTs of `r LST24hrPopTab[5,3]` below the regional average.
```{r plotLST24hrTempPopAvgNE, echo=FALSE, message=FALSE, warning=FALSE, fig.align = "center", fig.cap="Population-weighted average exposures to day-night average temperatures for populations of concern in New England relative to the regional average."}
LST24hrPop %>%
ggplot(aes(x = reorder(Group,LST24hrwMean),
y = LST24hrwMean)) +
geom_segment(aes(x = reorder(Group,LST24hrwMean),
xend = reorder(Group,LST24hrwMean),
y = LST24hrMean, yend = LST24hrwMean),
color = "firebrick1") +
geom_point(color = "firebrick4", size = 4, alpha = 0.8) +
coord_flip() +
labs(x = "", y = "", title = "Population-Weighted Temperature Exposure to\nDay-Night Average LST (°F)") +
theme_light() +
theme(panel.grid.major.y = element_blank(),
panel.border = element_blank(),
axis.ticks.y = element_blank()) +
geom_text(aes(x = Group, y = LST24hrwMean + 0.2 * sign(LST24hrwMean),
label = paste0(round(LST24hrwMean,1),"°")),
hjust = 1.6, vjust = -.8, size = 3,
color=rgb(100,100,100, maxColorValue=255)) +
scale_y_continuous(labels = function(x) paste0(x, "°")) +
geom_hline(yintercept = LST24hrPop$LST24hrMean, linetype = "dashed") +
geom_text(aes(x = "Low Income", y = 80.5, label = "Above regional\naverage"),
color = "gray48") +
geom_text(aes(x = "Low Income", y = 77, label = "Below regional\naverage"),
color = "gray48") +
# geom_segment(aes(x = "Under 5", xend = "Under 5", y = 79.5, yend = 81),
# arrow = arrow(length = unit(0.3,"cm"))) +
expand_limits(y = c(76,83))
```
```{r tabLST24hrPopAvgNE, fig.align = "center", fig.cap="Population-weighted average exposures to day-night average LST for populations of concern in New England relative to the regional average."}
LST24hrPopTab %>%
arrange(Group) %>%
kableExtra::kable(longtable = T, booktabs = T, digits = 2,
col.names = c("Group","Avg 24hr LST (°F)",
"Difference from Regional Avg* (°F)",
"Pct Above/Below Regional Avg*"),
caption = "Population-Weighted Temperature Exposure - Day-Night Average LST", align = "r") %>%
kableExtra::column_spec(2:4, width = "4cm") %>%
kableExtra::kable_styling(latex_options = c("repeat_header")) %>%
kableExtra::footnote(., symbol = paste0("Regional average day-night LST is ", round(mean(ne_blkgrpLST_sf$meanAvgLST,na.rm=TRUE),2), "°"))
```
```{r UHI24hrTempPop, include=FALSE}
# Pop Weighted avg of 24hr LST exposure for all Groups in New England relative to NE average
UHI24hrPop <- ne_blkgrpLST_sf %>%
as.data.frame() %>%
# filter(STATE == "Massachusetts") %>%
dplyr::select(totalpopE,
nhwhitepopE,
minorityE,
nhblackpopE,
nhamerindpopE,
nhasianpopE,
nhnativhpopE,
nhotherpopE,
nh2morepopE,
hisppopE,
povknownE,
num2povE,
eng_hhE,
eng_limitE,
age25upE,
lthsE,
allAgesE,
under5E,
over64E,
UHI24avg) %>%
gather(key = Group, value = Pop, totalpopE:over64E) %>%
group_by(Group) %>%
summarize(UHI24hrwMean = weighted.mean(x = UHI24avg, w = Pop, na.rm = TRUE),
UHI24hrMean = mean(UHI24avg, na.rm = TRUE)) %>%
filter(Group %in% c("minorityE","eng_limitE","num2povE","lthsE","under5E","over64E")) %>%
mutate(Group = case_when(
Group == "minorityE" ~ "Minority",
Group == "eng_limitE" ~ "Limited English HH",
Group == "num2povE" ~ "Low Income",
Group == "lthsE" ~ "No HS Dip",
Group == "under5E" ~ "Under 5",
Group == "over64E" ~ "Over 64"))
# Pop Weighted avg of PM2.5 for all Groups in New England relative to NE average
UHI24hrPopTab <- ne_blkgrpLST_sf %>%
as.data.frame() %>%
# filter(STATE == "Massachusetts") %>%
dplyr::select(totalpopE,
nhwhitepopE,
minorityE,
nhblackpopE,
nhamerindpopE,
nhasianpopE,
nhnativhpopE,
nhotherpopE,
nh2morepopE,
hisppopE,
povknownE,
num2povE,
eng_hhE,
eng_limitE,
age25upE,
lthsE,
allAgesE,
under5E,
over64E,
UHI24avg) %>%
gather(key = Group, value = Pop, totalpopE:over64E) %>%
group_by(Group) %>%
summarize(UHI24hrwMean = weighted.mean(x = UHI24avg, w = Pop, na.rm = TRUE),
UHI24hrMean = mean(UHI24avg, na.rm = TRUE)) %>%
spread(key = Group, value = UHI24hrwMean) %>%
transmute(Minority = (minorityE/UHI24hrMean - 1)*100,
#Minority_NHW = (minorityE/nhwhitepopE - 1)*100,
`Limited English HH` = (eng_limitE/UHI24hrMean - 1)*100,
`Low Income` = (num2povE/UHI24hrMean - 1)*100,
`No HS Dip` = (lthsE/UHI24hrMean - 1)*100,
`Under 5` = (under5E/UHI24hrMean - 1)*100,
`Over 64` = (over64E/UHI24hrMean - 1)*100) %>%
gather(key = Group, value = Pct) %>%
left_join(x = UHI24hrPop, y = ., by = "Group") %>%
mutate(Difference = UHI24hrwMean - UHI24hrMean) %>%
transmute(Group = Group,
UHI24hrwMean = paste0(round(UHI24hrwMean,2),"°"),
Difference = if_else(Difference > 0,
paste0("+",round(Difference,2),"°"),
paste0(round(Difference,2),"°")),
Pct = if_else(Pct > 0, paste0("+",round(Pct,2),"%"),
paste0(round(Pct,2),"%")))
```
Figure \@ref(fig:plotUHI24hrTempPopAvgNE) and Table \@ref(tab:tabUHI24hrPopAvgNE) show population-weighted exposures for populations of concern relative to the day-night average Urban Heat Island (UHI) effect for New England. All populations of concern are exposed to the UHI effect on average. Indeed, the average UHI effect across New England is approximately `r round(mean(ne_blkgrpLST_sf$UHI24avg,na.rm=TRUE),1)`°. However, some populations experience significantly higher UHI effects. For example, limited English speaking households in New England were exposed to a population-weighted day-night average UHI effect of `r round(max(UHI24hrPop$UHI24hrwMean),1)`° above the rural average. This value is more than `r round(max(UHI24hrPop$UHI24hrwMean) - max(UHI24hrPop$UHI24hrMean),1)`° (`r UHI24hrPopTab[1,4]`) above the regional day-night average UHI. Similarly, minorities were exposed to a population-weighted day-night average UHI effect of `r UHI24hrPop %>% filter(Group == "Minority") %>% summarize(round(max(UHI24hrwMean),1)) %>% pull()`°, approximately `r round(UHI24hrPop %>% filter(Group == "Minority") %>% summarize(max(UHI24hrwMean)) %>% pull() - max(UHI24hrPop$UHI24hrMean),1)`° (`r UHI24hrPopTab[3,4]`) above the regional day-night average UHI. By contrast, persons over age 64 were, on average, were exposed to a population-weighted day-night average UHI of `r UHI24hrPopTab[5,3]` (`r UHI24hrPopTab[5,4]`) below the regional average.
```{r plotUHI24hrTempPopAvgNE, echo=FALSE, message=FALSE, warning=FALSE, fig.align = "center", fig.cap="Population-weighted average exposures to day-night average Urban Heat Island effect for populations of concern in New England."}
UHI24hrPop %>%
ggplot(aes(x = reorder(Group,UHI24hrwMean),
y = UHI24hrwMean)) +
geom_segment(aes(x = reorder(Group,UHI24hrwMean),
xend = reorder(Group,UHI24hrwMean),
y = 0, yend = UHI24hrwMean),
color = "firebrick1") +
geom_point(color = "firebrick4", size = 4, alpha = 0.8) +
coord_flip() +
labs(x = "", y = "", title = "Population-Weighted Temperature Exposure to\nDay-Night Average UHI (°F)") +
theme_light() +
theme(panel.grid.major.y = element_blank(),
panel.border = element_blank(),
axis.ticks.y = element_blank()) +
geom_text(aes(x = Group, y = UHI24hrwMean + 0.2 * sign(UHI24hrwMean),
label = paste0(round(UHI24hrwMean,1),"°")),
hjust = 1.6, vjust = -.8, size = 3,
color=rgb(100,100,100, maxColorValue=255)) +
scale_y_continuous(labels = function(x) paste0(x, "°")) +
geom_hline(yintercept = 0, linetype = "dashed") +
# geom_text(aes(x = "Under 5", y = 12, label = "Above\nrural average"),
# color = "gray48") +
# geom_segment(aes(x = "Over 64", xend = "Over 64", y = 9, yend = 12),
# arrow = arrow(length = unit(0.3,"cm"))) +
expand_limits(y = c(-2,15))
```
```{r tabUHI24hrPopAvgNE, fig.align = "center", fig.cap="Population-weighted average exposures to day-night average Urban Heat Island effect for populations of concern in New England relative to the rural average."}
UHI24hrPopTab %>%
arrange(Group) %>%
kableExtra::kable(longtable = T, booktabs = T, digits = 2,
col.names = c("Group","Day-Night Avg UHI (°F)",
"Difference from Regional UHI Avg* (°F)",
"Pct Above/Below Regional UHI Avg*"),
caption = "Population-Weighted Temperature Exposure - Day-Night Avg UHI", align = "r") %>%
kableExtra::column_spec(2:4, width = "4cm") %>%
kableExtra::kable_styling(latex_options = c("repeat_header")) %>%
kableExtra::footnote(., symbol = paste0("Regional average day-night UHI effect is ", round(mean(ne_blkgrpLST_sf$UHI24avg,na.rm=TRUE),2), "°"))
```
Because the risk of heat-related illness is a combination of both exposure and vulnerability, it is important to consider where these factors come together. Figures \@ref(fig:mapLST24hrHighRiskLEH) and \@ref(fig:mapLST24hrHighRiskMIN) highlight Census Block Groups across New England which exhibited day-night average LSTs in the top quintile (i.e., 80th percentile) and also contained high percentages of limited English speaking households or minorities in the top quintile for the region.[^LST24quintile] These high risk locations were present across four New England states in the late summer of 2019. Tables \@ref(tab:tabLST24hrHighRiskLEH) and \@ref(tab:tabLST24hrHighRiskMIN) show breakdowns of how many households these represent for each state, and the day-night average LST values for those same Census Block Groups. Note that Massachusetts contains the largest number of these at-risk households, over 67,000, as well as at-risk minority persons, over 650,000, while Rhode Island shows the highest day-night average LSTs for these at-risk housholds, on average over 86.7°, and over 87° for at-risk minorities. Maps and tables for other populations of concern can be found in Figures \@ref(fig:mapLST24hrHighRiskLI) to \@ref(fig:mapLST24hrHighRiskU5) and Tables \@ref(tab:tabLST24hrHighRiskLI) to \@ref(tab:tabLST24hrHighRiskU5) in Appendix B.
```{r mapLST24hrHighRiskLEH, fig.align = "center", fig.cap="Map of Block Groups in the highest quintile (80th percentile) of day-night average LST and 80th percentile of percentage of Limited English Speaking Households by Census Block Group, July-Aug 2019."}
LST24EngLang5 <- ne_blkgrpLST_sf %>%
filter(LST24EngLangScore == 5)
bbox_new <- st_bbox(LST24EngLang5) # current bounding box
xrange <- bbox_new$xmax - bbox_new$xmin # range of x values
yrange <- bbox_new$ymax - bbox_new$ymin # range of y values
# bbox_new[1] <- bbox_new[1] - (0.5 * xrange) # xmin - left
bbox_new[3] <- bbox_new[3] + (0.2 * xrange) # xmax - right
# bbox_new[2] <- bbox_new[2] - (0.5 * yrange) # ymin - bottom
bbox_new[4] <- bbox_new[4] + (0.2 * yrange) # ymax - top
bbox_new <- bbox_new %>% # take the bounding box ...
st_as_sfc() # ... and make it a sf polygon
m <- tm_shape(LST24EngLang5, unit = "mi" , bbox = bbox_new) + tm_fill(col = "red", title = "80th Percentile", legend.is.portrait = TRUE) +
tm_shape(ne_states_sf_cb) + tm_polygons(alpha = 0.4, lwd = 0.2) +
tm_text("STUSPS", size = 0.7, remove.overlap = TRUE, col = "gray") +
tm_shape(ne_towns_sf_pts) + tm_dots() +
tm_text("NAME", size = 0.5, col = "black", xmod = 0.7, ymod = 0.2) +
tm_scale_bar(breaks = c(0, 50, 100), text.size = 0.5,
position = c(0.4,0.005)) +
tm_add_legend(type = "fill",
labels = "80th Percentile Block Groups",
col = "red",
border.col = "white", border.alpha = 0) +
tm_layout(title = "Highest Exposure\nand Vulnerability\nto Day-Night Avg\nTemps for Limited\nEnglish Speaking\nHouseholds\nJuly-Aug 2019",
frame = FALSE, main.title.size = 0.8,
legend.outside = TRUE,
legend.title.size = 0.8,
legend.outside.position = c("right", "top"),
legend.hist.width = 0.9)
tmap_save(m, "DATA/LST/ne_LST24EngLang5.png",
height = 5, width = 8, units = "in", dpi = 600)
knitr::include_graphics("DATA/LST/ne_LST24EngLang5.png")
```
```{r tabLST24hrHighRiskLEH, fig.align = "center", fig.cap="Limited English Housheolds in Census Block Groups at or above 80th percentile of day-night average Land Surface Temperature."}
ne_blkgrpLST_sf %>%
as.data.frame() %>%
left_join(., statepopsdf,by="STATE") %>%
filter(LST24EngLangScore == 5) %>%
group_by(STATE) %>%
summarize(`Limited English Households` = sum(eng_limitE),
`Pct of Limited English Households` = round(sum(eng_limitE)/max(TotalLEH)*100,1),
Min = min(meanAvgLST,na.rm=TRUE),
Mean = mean(meanAvgLST,na.rm=TRUE),
Max = max(meanAvgLST,na.rm=TRUE)) %>%
mutate(`Pct of Limited English Households` = paste0(`Pct of Limited English Households`,"%"),
Min = paste0(round(Min,2),"°"),
Mean = paste0(round(Mean,2),"°"),
Max = paste0(round(Max,2),"°")) %>%
kableExtra::kable(longtable = F, booktabs = T,
format.args = list(big.mark = ','),
digits = 1,
caption = "Limited English Speaking Households in Highest Quintile of Day-Night Avg LST", align = "r") %>%
kableExtra::kable_styling(latex_options = c("repeat_header")) %>%
kableExtra::column_spec(2:3, width = "3cm") %>%
kableExtra::add_header_above(c(" " = 3, "Day-Night LST (°F)" = 3))
```
```{r mapLST24hrHighRiskMIN, fig.align = "center", fig.cap="Map of Block Groups in the highest quintile (80th percentile) of day-night average LST and 80th percentile of percentage of Minorities by Census Block Group, July-Aug 2019."}
LST24Minority5 <- ne_blkgrpLST_sf %>%
filter(LST24MinorScore == 5)
bbox_new <- st_bbox(LST24EngLang5) # current bounding box
xrange <- bbox_new$xmax - bbox_new$xmin # range of x values
yrange <- bbox_new$ymax - bbox_new$ymin # range of y values
# bbox_new[1] <- bbox_new[1] - (0.5 * xrange) # xmin - left
bbox_new[3] <- bbox_new[3] + (0.2 * xrange) # xmax - right
# bbox_new[2] <- bbox_new[2] - (0.5 * yrange) # ymin - bottom
bbox_new[4] <- bbox_new[4] + (0.2 * yrange) # ymax - top
bbox_new <- bbox_new %>% # take the bounding box ...
st_as_sfc() # ... and make it a sf polygon
m <- tm_shape(LST24Minority5, unit = "mi", bbox = bbox_new) + tm_fill(col = "red", title = "80th Percentile", legend.is.portrait = TRUE) +
tm_shape(ne_states_sf_cb) + tm_polygons(alpha = 0.4, lwd = 0.2) +
tm_text("STUSPS", size = 0.7, remove.overlap = TRUE, col = "gray") +
tm_shape(ne_towns_sf_pts) + tm_dots() +
tm_text("NAME", size = 0.5, col = "black", xmod = 0.7, ymod = 0.2) +
tm_scale_bar(breaks = c(0, 50, 100), text.size = 0.5,
position = c(0.4,0.005)) +
tm_add_legend(type = "fill",
labels = "80th Percentile Block Groups",
col = "red",
border.col = "white", border.alpha = 0) +
tm_layout(title = "Highest Exposure\nand Vulnerability\nto Day-Night Avg\nTemps for\nMinorities\nJuly-Aug 2019",
frame = FALSE, main.title.size = 0.8,
legend.outside = TRUE,
legend.title.size = 0.8,
legend.outside.position = c("right", "top"),
legend.hist.width = 0.9)
tmap_save(m, "DATA/LST/ne_LST24Minority5.png",
height = 5, width = 8, units = "in", dpi = 600)
knitr::include_graphics("DATA/LST/ne_LST24Minority5.png")
```
\pagebreak
```{r tabLST24hrHighRiskMIN, fig.align = "center", fig.cap="Minorities in Census Block Groups at or above 80th percentile of day-night average Land Surface Temperature."}
ne_blkgrpLST_sf %>%
as.data.frame() %>%
left_join(., statepopsdf,by="STATE") %>%
filter(LST24MinorScore == 5) %>%
group_by(STATE) %>%
summarize(Minorities = sum(minorityE),
`Pct of Minorities` = round(sum(minorityE)/max(TotalMin)*100,1),
Min = min(meanAvgLST,na.rm=TRUE),
Mean = mean(meanAvgLST,na.rm=TRUE),
Max = max(meanAvgLST,na.rm=TRUE)) %>%
mutate(`Pct of Minorities` = paste0(`Pct of Minorities`,"%"),
Min = paste0(round(Min,2),"°"),
Mean = paste0(round(Mean,2),"°"),
Max = paste0(round(Max,2),"°")) %>%
kableExtra::kable(longtable = T, booktabs = T,
format.args = list(big.mark = ','),
digits = 1,
caption = "Minorities in Highest Quintile of Day-Night Avg LST", align = "r") %>%
kableExtra::kable_styling(latex_options = c("repeat_header")) %>%
kableExtra::column_spec(2:3, width = "3cm") %>%
kableExtra::add_header_above(c(" " = 3, "Day-Night LST (°F)" = 3))
```
\pagebreak
## Daytime Average Land Surface Temperatures
Daytime Average Land Surface Temperatures (LST) represent LST values collected during the day (11:48am - 2pm) over eight days, from July 28 to August 4, 2019. The average daytime LST for the region was `r round(mean(ne_blkgrpLST_sf$meanDayLST,na.rm=TRUE),1)`°F. Daytime Land Surface Temperatures (LST) varied significantly across New England, with highest temperatures apparent in the most urbanized areas of the region, particularly along the I-95 corridor from Stamford, Connecticut to New Haven, and along the I-91 corridor from New Haven through Hartford to Springfield, Massachusetts. This is also apparent around greater Providence, Rhode Island, and the greater Boston region out to I-495, and reaching into southern New Hampshire. Note that pockets of high daytime LST are also present in pockets across Maine (see Figure \@ref(fig:mapLSTdayNE) below). Across New England, approximately `r ne_blkgrpLST_sf %>% as.data.frame() %>% filter(pctileDayLST >= 0.8) %>% group_by() %>% summarize(sum(totalpopE, na.rm = TRUE)/10^6) %>% pull() %>% round(.,2)` million people live in Block Groups that exceeded the 80th percentile (temperatures over `r round(quantile(ne_blkgrpLST_sf$meanDayLST,0.8,na.rm=TRUE),1)`°) for daytime average temperatures.
```{r mapLSTdayNE, fig.align = "center", fig.cap="Map of July-August 2019 average daytime Land Surface Temperatures (LST) across New England at Census Block Group level.", strip.white=TRUE}
# Map of average LST across New England
m <- tm_shape(ne_blkgrpLST_sf, unit = "mi") +
tm_fill("meanDayLST", style = "quantile", palette = "Reds",
title = expression("Temperature " ( degree*F)),
legend.hist = FALSE,
colorNA = NULL,
textNA = NULL,
legend.format=list(list(digits=1)),
legend.is.portrait = TRUE) +
tm_shape(ne_states_sf_cb) + tm_borders(alpha = 0.4, lwd = 0.5) +
tm_text("STUSPS", size = 0.7, remove.overlap = TRUE, col = "gray") +
tm_shape(ne_towns_sf_pts) + tm_dots() +
tm_text("NAME", size = 0.5, col = "black", xmod = 0.7, ymod = 0.2) +
tm_scale_bar(breaks = c(0, 50, 100), text.size = 0.5,
position = c(0.6,0.005)) +
tm_layout(title = "Average Day\nLand Surface\nTemperatures\nJuly-Aug 2019",
frame = FALSE, main.title.size = 0.8,
legend.outside = TRUE,
legend.title.size = 0.8,
legend.outside.position = c("right", "top"),
legend.hist.width = 0.9)
tmap_save(m, "DATA/LST/ne_DayLST.png",
height = 8, width = 8, units = "in", dpi = 600)
knitr::include_graphics("DATA/LST/ne_DayLST.png")
```
```{r LSTDayoutliers, include=FALSE}
# # download municipal polygons
# nh_towns_sf <- county_subdivisions("NH") %>%
# dplyr::select(NAME) %>%
# st_transform(., crs = st_crs(ne_blkgrpLST_sf))
#
# me_towns_sf <- county_subdivisions("ME") %>%
# dplyr::select(NAME) %>%
# st_transform(., crs = st_crs(ne_blkgrpLST_sf))