GoM 'dead zone': Good news & bad

The Gulf of Mexico dead zone will be big, but won't likely break any records, according to scientists at the National Oceanographic and Atmospheric Administration. In summer, as waters warm and spring rains flush nutrients from the Mississippi watershed, a low-oxygen area becomes an underwater ghost town. Sea creatures who can leave, do. Those that can’t die. Before each hurricane season, researchers make forecasts about how bad it’ll be. NOAA predicted the dead zone will grow to about 6,700 square miles – bigger than Connecticut, smaller than New Jersey. The long-term average for the region, between 10-to-60 miles off the Louisiana coast, is 5,387 square miles. In 2017’s record year, it was 8,776 square miles. The dead zone can stretch from Texas to Alabama. This year’s high spring rainfall, river discharges and nutrient loads should make for an above-average region of low to no oxygen levels. Major contributors are agriculture and urban runoff. When excess nutrients reach the GoM, they essentially fertilize the waters, says Mike Parsons, a Florida Gulf Coast University professor of marine biology. The impacted areas encompass about 40 percent of the continental U.S. - 20+ states - and parts of Canada. “It’s a really big issue.” The dead zone hurts marine life, commercial and recreational fishers and communities, says Nicole LeBoeuf, acting director of NOAA’s National Ocean Service. The USGS operates more than 3,000 real-time stream gauges, 50 real-time nitrate sensors, and 35 long-term monitoring sites to measure nutrients in rivers throughout the Mississippi-Atchafalaya watershed. Scientists use these data to track long-term changes in nutrient inputs to the Gulf and help build models of nutrient sources and hotspots within the watershed. (Source: News Press 06/04/20) A recent study, reported by NOLA.com, says the effects of the dead zone could be as much as $2.4B on Gulf fisheries. https://www.news-press.com/story/tech/science/environment/2020/06/04/gulf-mexico-dead-zone-scientists-crunch-data-mark-summers-predicition/3136079001/