Rising Environmental Inequalities and Their Relationship to Racial and Socioeconomic Disparities in the US Southwest.

The US Southwest, the hottest and driest region in the US, faces significant climate-coupled challenges to sustainable development by human and natural systems. This study examines how inequalities in race and ethnicity have shifted with climate impact, analyzing disparities in socioeconomic conditions, remote sensing-based environmental metrics, and environmental changes (2000-2020). Results reveal widespread racial and ethnic disparities in social and environmental conditions. From 2000 to 2020, environmental inequalities increased, with significant differences in land surface temperature (LST) (Sen's slope differences: 0.00620 °C/year for Hispanic vs non-Hispanic (ethnic group); 0.00366 °C/year for people of color vs non-Hispanic White (racial group) and actual evapotranspiration (ETa) as a proxy for consumptive water use (-0.00167 mm/year for ethnic groups). LST disparities among races/ethnicities grew in warmer regions, while they decreased in temperate and cold areas. Water resource disparities also increased across different ethnic groups in drier neighborhoods, with a slope of ETa differences at -0.00237 mm/year. These findings highlight the linkages between environmental inequality, physiography, and climate change, demonstrating that climate change exacerbates these disparities. We recommend that urban planners and managers expand green spaces in vulnerable neighborhoods and communities to mitigate the disproportionate impact of climate change and enhance urban resilience to heat extremes and droughts for the entire urban setting.