text
stringlengths 0
6.44k
|
---|
exposure within the urban region. One alternative approach, |
recently advanced by Miami–Dade County, is to talk about a |
“heat season” that could draw from the lessons of “hurricane |
season” (Harris 2021). Thus, rather than focusing on specific |
events, there would be an increased level of public and professional awareness and associated resources available in summer |
months (Kotcher et al. 2021; Salas 2021), when the area is under persistent high heat exposure. This would be consistent |
with our findings that levels of heat exposure that have been |
deemed dangerous (such as the 1088F threshold) occurs in locations within the urbanized area of Miami–Dade County for a |
significant part of the year (Fig. 4b) while avoiding the concerns |
around “warning fatigue.” |
Naturally, these results lead to the question of impacts. The |
current NWS approach is tied to health impacts by examining |
the rate of heat related emergency room admissions in central |
Florida (Florida Department of Health 2011). However, this |
approach misses the potential granularity of heat-health impacts since health data that have been used is most often at the |
county scale (Anderson and Bell 2011; McElroy et al. 2020). |
Even changing to a single county-specific heat index threshold, |
instead of a statewide one, may miss varying exposures and |
impacts, since we have shown considerable variations in |
heat index within the county (Fig. 3). There are also disproportionate risks to different groups such as the elderly (Kenney |
and Munce 2003; Semenza et al. 1999), pregnant women |
(Zhang et al. 2017), people with preexisting conditions (Leon |
and Bouchama 2011), outdoor workers (Uejio et al. 2018), and |
members of low-income communities who often cannot afford |
adequate air conditioning (Dahl et al. 2019). This suggests that |
disaggregation of both health and heat exposure data may be |
important to identifying impacts. Further, there are other heatrelated impacts such as productivity, that may not be easy to tie |
to a single threshold given the varying exposures throughout |
the county, since they will depend on the length of time of exposure and physical activity (Uejio et al. 2016; Masuda et al. |
2019; Vanos et al. 2020; Oppermann et al. 2021). This may be |
even more challenging in Miami where high temperature and |
humidity, producing elevated heat indices, persist throughout a |
significant part of the year, generally from May to October. These |
chronic heat conditions can lead to impacts that may be difficult |
to detect when judged by a correlation with extremes (Bolitho |
and Miller 2017; Casanueva et al. 2019; Oppermann et al. 2021; |
FIG. 3. Scatterplots of daily iButton vs MIA (Airport) (a) minimum temperature (Tmin), (b) maximum temperature (Tmax), and |
(c) maximum heat index (HImax). For (a) and (b), red points represent 65 iButtons measuring temperature in locations determined |
by participants to be sunny (open canopy); blue points represent 54 |
iButtons measuring temperature in locations determined by participants to be shaded (treed). For (c), red points represent 6 iButtons |
measuring relative humidity in addition to temperature in sunny |
locations; blue points represent 4 iButtons measuring relative humidity and temperature in shaded locations. The line of best fit based on |
linear regression with 95% confidence (light shading) is calculated |
for the sunny and shaded values and is shown in the iButton environment’s respective color. Each regression line’s R-squared value is |
given in the legend. The gray line is a 1-to-1 reference line. |
868 JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY VOLUME 62 |
Unauthenticated | Downloaded 02/29/24 07:14 AM UTC |
Strathearn et al. 2022) and may require new ways of relating |
heat and health data (Hondula et al. 2021, 2022). These |
questions clearly require a more complete analysis of where |
and how different groups are being impacted by heat to design more locally relevant and appropriate policy actions |
(Turek-Hankins et al. 2020), as recommended in earlier |
Florida Department of Health (2011) reports. This kind of |
analysis should also be paired with heat exposure data that |
are closer to the experience of vulnerable groups. |
The question of what dangerous levels of heat occur |
within urban communities is a pressing one. Our data suggest that the heat index is higher and more persistent in many |
parts of Miami–Dade County than is measured at the Miami |
NWS station and can place many parts of the county well |
above a single heat index threshold when accounting for local |
conditions. Local conditions can introduce significant variability in heat exposure, which is important in attributing health |
and other impacts that may be missed at the scale of a county |
jurisdiction. Monitoring heat exposure at more locally relevant |
scales, ideally in real time, is an important part of how cities can |
plan proactively for current and future heat impacts (McCormick |
2021), and to assess whether management interventions are |
working as intended. We argue that the best way forward is a |
multiplatform collection of sensors collecting at multiple spatial |
and temporal scales for a more integrated and relevant reporting |
of heat exposure, including stationary, mobile, and remote |
sensing coupled with NWS monitoring data as has been |
identified in previous heat studies (e.g., Shi et al. 2021). |
There are also arguments to be made for including indoor |
temperature measurements in order to understand heat exposure in the home, which can differ considerably from |
outdoor temperatures (Uejio et al. 2016, 2018). Hyperlocal |
data are an important part of this monitoring and have the |
additional opportunity of directly connecting to community members who are affected by and should be part of |
the discussion of mitigating heat exposure in urban |
communities. |
Acknowledgments. We acknowledge SLSC volunteer |
Bertha Goldenberg, citizen scientists, Catalyst Miami, City |
of Miami, Miami–Dade County, City of Miami Beach, |
Kresge Foundation, Miami’s Urban Heat Research Group, |
Jane Gilbert, Lynee Turek-Hankins, Kenny Broad, and |
NOAA’s Climate and Equity Roundtables (https://www. |
noaa.gov/regional-collaboration-network/noaas-climate-andequity-roundtables). We are grateful to Robert Molleda for |
information he shared from the NWS Miami office. Partial |
funding support for this work came from the University of |
Miami Laboratory for Integrated Knowledge and the NOAA |
Adaptation Science program. |
FIG. 4. The number of days per year in which the heat index, calculated (a) using data at MIA |
and (b) using modeled iButton data, reached or exceeded 1028, 1048, 1068, and 1088F (38.98, 408, |
41.18 and 42.28C, respectively) from 1950 to 2020. The modeled iButton data for heat index were |
based on the regression line from the iButton temperature scatterplot slopes. |
JULY 2023 CLEMENT ET AL. 869 |
Unauthenticated | Downloaded 02/29/24 07:14 AM UTC |
Data availability statement. NWS data are publicly available |
online (https://www.ncei.noaa.gov/cdo-web/). The hyperlocal |
observations shown in this paper are available at our website |
(https://amyclement.weebly.com/data.html). |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.