What is the economic impact of ocean warming?

Marine tourism and entertainment have contributed a significant number of job opportunities and brought considerable goods and services to the United States. However, in the summer of 2023, the water temperature near Miami reached an astonishing 101 degrees Fahrenheit, greatly reducing tourists' interest in swimming in the sea. With the warming of the ocean and the resulting storms, rising sea levels, and ocean heatwaves, the future of some employment and businesses in the marine economy is full of uncertainty.

Firstly, one of the major threats of ocean warming to the economy is rising sea levels. The expansion of warm seawater, combined with the melting of glaciers and ice sheets, leads to an increase in the volume of seawater and frequent flooding in low-lying coastal areas. Louisiana in the United States puts Charles Island and Tangier Island in Chesapeake Bay at risk of being submerged in the future. Floods during high tide are becoming increasingly common in places such as Miami Beach, Annapolis, Maryland, Norfolk, Virginia, and San Francisco. Since 2000, the number of high tide floods has more than doubled, and it is expected that by 2050, the number of high tide floods in coastal areas of the United States will double. In addition, rising sea levels can also cause saltwater to invade freshwater aquifers, posing a threat to agricultural water use. Strawberry crops in the coastal areas of California have been affected by this intrusion of saline water.

Secondly, rising sea levels may exacerbate the damage caused by storms. The warm seawater has intensified the frequency and intensity of tropical storms, which is one of the reasons why meteorologists predict an unusually frequent hurricane season in 2024. Tropical storms absorb water from warm waters and transfer it to cooler areas. As the water temperature rises, storms form faster, strengthen faster, and last longer, leading to more destructive storms and rainstorm, and may even flood cities far away from the coast. From 1980 to 2023, tropical cyclones caused over $1.3 trillion in damage to the United States, with an average loss of $22.8 billion per storm, mostly borne by federal taxpayers.

In addition, ocean heatwaves have caused difficulties for the fishing industry. The rise in seawater temperature not only affects marine life through extreme events, but also through long-term temperature changes. In the spring of 2024, one-third of the world's oceans experienced heatwaves, leading to the fourth global coral bleaching event. Coral reefs are breeding and feeding grounds for thousands of fish species. According to estimates from the National Oceanic and Atmospheric Administration of the United States, approximately half of all federally managed fisheries rely on coral reefs, including snappers and groupers, at some stage of their lifecycle. Warming seawater causes fish to migrate to colder areas, which is particularly evident for species that prefer cold water, such as lobsters, who have been migrating northward to escape the warming seawater.

Currently, it appears that even if countries achieve their goal of reducing greenhouse gas emissions to zero by 2050, the accumulated heat in the oceans and greenhouse gases in the atmosphere will continue to affect ocean temperatures in the coming centuries. Therefore, although ocean temperatures fluctuate every year, the overall trend may continue to rise for at least a century. In summary, due to the uncertainty of the speed and extent of sea level rise, the potential losses that sea level rise may cause to the future economy of the United States are also unclear. Even if immediate measures are taken, the seawater temperature will not return to normal in a short period of time. Therefore, the United States must adapt to this change, while the world also needs to work to reduce greenhouse gas emissions to protect the future marine economy.

Marine tourism and entertainment are important pillars of the US economy, but the challenges brought by ocean warming cannot be ignored. Rising sea levels, intensifying storms, and ocean heatwaves pose a serious threat to coastal communities and fisheries. Despite measures taken to mitigate climate change, its impact will continue in the future. The United States and the world must work together to reduce greenhouse gas emissions, adapt to the constantly changing environment, and protect the marine economy and people's livelihoods.