Discipline: Ecology Environmental and Earth Sciences
Subcategory: Ecology
Tori Farrow - Kentucky State University
Co-Author(s): Jeremy Sandifer, Kentucky State University, Frankfort, Kentucky ; Buddhi Gyawali, Kentucky State University, Frankfort, Kentucky
The Urban Heat Island is a general term used to describe a relative warming of the surface and atmosphere in the urban core relative to the surrounding non-urban natural or ‘rural’ areas. The increase in temperature of the urban area results from the transformation of the former natural landscape dominated by trees, shrubs, and grasses, to a landscape dominated by concrete and asphalt that proves very effective at absorbing the daytime energy from the sun and re-radiating that energy leading to increases in temperatures, especially at night. In the United States, this change in landscape cover over time is generally spatially coincident to changes in the socio-economic make-up and distribution of population living within that landscape. In this current study, we test the hypotheses that magnitude of environmental change is dependent on the socio-economic indicators of population density, income, race, and age structure in Detroit, Michigan. Socioeconomic variables were derived from the 2017 American Community Survey (ACS) at the census tract level, processed into percentages, and segmented into 2 groups (above and below median). Environmental change variables were derived from the Moderate Resolution imaging spectro-radiometer (MODIS) instruments, including the normalized difference vegetation index (NDVI) and land surface temperatures (LSTs). Environmental variables were evaluated by applying a simple linear model to determine the mean change in magnitude for each monthly time step from 2000 to 2017. Preliminary results show that NDVI is generally increasing overall but varies substantially according to the demographics of the population of the particular area ranging from no change to increases of up to 10% per year. Trends in land surface temperatures also vary substantially according the socio-economic condition of the particular tracts, ranging in per year changes from -0.6 to 1.0 degrees Celsius per year. In each case of environmental change (NDVI and LSTs), t-tests were administered to ascertain whether or not a significant difference in environmental change was detectable for each of the grouped (above and below median) socio-economic variables. Of the socio-economic variables, only the population density groups had significant differences in rates of change in NDVI and LSTs. These results are in line with expectations based on other literature reporting for other major metropolitan regions in the United States. This study is limited by the use of only static socio-economic variables (2017) which fail to indicate how these variables (income, density, etc.) are changing over time. Detroit is undergoing complex socio-economic change including widespread neighborhood gentrification that is not evident when considering static population values. Future research will include the addition of population change metrics to determine the influence of ongoing social change on rates of environmental change in this region.
Funder Acknowledgement(s): Developing Minor in Geoscience Application at Kentucky State University NSF-HBCU-UP_TIP #1332477; Promoting Minority Students' Participation in STEM-Undergraduate Degree Programs, NSF HBCU-UP-TIP #1436426; Strengthening Environmental Science Program for Preparing Minority Young Scientists for the 21st Century USDA/NIFA # 2013-38821-21120
Faculty Advisor: Buddhi Gyawali, Buddhi.Gyawali@kysu.edu
Role: I completed all aspects of this project with substantial effort on the part of my co-authors, including literature review, data collection and processing, and writing.