When people in the Southern and Midwestern United States think of the consequences of climate change, people tend to think about extreme events like hurricanes and floods. However, another consequence of climate change that is currently causing headaches is the opposite: drought. Outside of arid Western states, people generally do not place enough concern on the impact of climate change increasing droughts. The increasing temperatures on the planet promote both drought and extreme rain events. The reason for this is that warmer air with low moisture will dry soil more quickly, increasing evaporation and drought. However, that warmer air also holds more moisture, resulting in heavier rainfalls in a shorter period.
The World’s Shipping Channel – The Mississippi
The Mississippi River is the largest drainage basin in the United States and the second-longest river in North America. Roughly 8% of the world’s population consumes food originating from the Mississippi River Basin. Upwards of 40% of the global food supply comes from the Mississippi River Basin. Put starkly, most of American agriculture depends on the Mississippi River to feed the world.
Beyond agriculture, we depend on the river to transport coal, fertilizer, sand and gravel, steel, aluminum, petroleum, and other commodities. The U.S. Army Corps of Engineers (USACE) estimates the Mississippi River carries more than 500 million tons of freight per year. As river levels deplete, the operational logistics of shipping that much freight becomes progressively more difficult.
The Effects of Drought on the Mississippi River
The Mississippi River is currently at its lowest levels in decades due to an extraordinary drought. Roughly 60% of the Midwest and Northern Great Plain states have experienced historically low rainfall over the past two months. The water levels are so low that it is threatening to ground barges and deep draft shipping. Exacerbating the problems is the fact that saltwater from the Gulf of Mexico is also now encroaching up the Mississippi River.
Louisiana Drinking Water at Risk
Due to the extreme drought, a wedge of saltwater has migrated more than 60 miles inland from the Gulf along the riverbed. That saltwater intrusion threatens parishes that sources their drinking water from the river. Plaquemines Parish declared a state of emergency recently due to compromised drinking water.
The Parish is bringing on desalinization units to remove the saltwater. Unfortunately, this is only a temporary fix since the salinity of the river at the water intake will increase as the wedge migrates further upriver. Sustained low levels would threaten drinking water in the metro New Orleans area as well. This is just a taste of the dilemmas that rising sea levels and global temperatures will cause.
Climate Change Solutions Are Needed
The Port of South Louisiana is an incredibly important asset for the country and the state. It ranks #1 in total domestic trade volume, #2 in total foreign trade and import volume, and #3 in exports volume. Hopefully the real and present threats now faced will serve as a shot across the bow for politicians and industry that depend on the Mississippi River, but resistant to climate regulation.