The National Oceanic and Atmospheric Administration (NOAA) is required to map the northern Gulf’s dead zone each year to set nutrient reduction goals and measure the progress being made by the national Hypoxia Task Force to reduce the dead zone’s size to less than 1,930 square miles by 2035. (The average size of the dead zone between 2015 and 2020 was 5,407 square miles. The 2020 dead zone was 2,117 square miles — the third smallest since mapping began in 1985, thanks to Hurricane Hanna, whose winds helped with water column mixing.)