The United States has been hit by natural disasters such as Hurricane Katrina or, several years later, Sandy or Patricia. What do all these phenomena have in common? Exactly, the temperature of the sea, which has just worried the experts: this is what they have found on our coast and which has been repeating itself for twelve months, raising concerns of the WMO.
WMO concerned about the United States: attention to our coastline
Over the past 12 consecutive months, global ocean temperatures have broken all previous records, alarming climate scientists worldwide. The unrelenting rise in ocean heat has profound consequences for Earth’s climate system and all life that depends on it.
According to the World Meteorological Organization (WMO), the global ocean heat content in 2024 is the highest since reliable records began over 60 years ago. The upper 2000 meters of the ocean continued to warm to record levels in 2024.
This sustained thermal anomaly has scientists terrified about what it means for the planet’s future. Record ocean temperatures affect weather systems, exacerbate extreme events, cause polar ice to melt faster, and lead to rising sea levels that threaten coastal communities.
Urgent action is required to curb further increases in greenhouse gas emissions and avoid the worst climate change scenarios. The past year of extreme ocean heat has provided a sobering look at what the future may hold if emissions are not drastically reduced in United States and the whole world.
Global warming starts with the water: U.S. coastline is boiling
The world’s oceans have reached unprecedented levels of heat in 2024, breaking temperature records for the 12th consecutive year according to data from the World Meteorological Organization (WMO). This is a circumstance that was predicted at the last Climate Summit and is now materializing.
Scientists report that ocean heat content and sea surface temperatures in 2024 were the highest on record, exceeding even the extreme ocean warmth of recent years. Global average sea surface temperatures were 0.26°C above the 1991-2020 average, surpassing the previous record set in 2023 in United States.
This persistent ocean warming is primarily driven by human-caused climate change, with the added influence of natural climate variability. The oceans absorb over 90% of the excess heat trapped by greenhouse gas emissions, leading to rising ocean temperatures that penetrate deep into the water column.
According to the WMO’s State of the Global Climate report, the upper 2,000 meters of the ocean continued to warm to record levels in 2024. The report highlights the complete domination of warming influences on climate, with no countervailing cooling factors in United States.
The regional impact, even more accelerated than the global one: what we might expect
The record-breaking ocean temperatures are not evenly distributed across the globe. Some regions have experienced more extreme warming than others. The Arctic Ocean in particular has seen dramatic temperature increases. Surface waters in parts of the Arctic are now 5-7°C above average.
This unprecedented warming is rapidly melting sea ice and threatening Arctic ecosystems. Indigenous communities who rely on sea ice for hunting, fishing, and transportation face an uncertain future. The Pacific Ocean has also seen considerable warming, especially along the United States West Coast.
The normally cool waters along the California coast have heated up significantly, leading to mass die-offs of fish and shellfish unused to the higher temperatures. Reduced nutrients and shifting currents in the Pacific are impacting fisheries and coastal residents who depend on them.
In the Atlantic Ocean, a key current known as the Gulf Stream is showing signs of slowing down. Scientists believe this may be linked to ocean warming disrupting global currents. A slowdown of the Gulf Stream would have major climate implications for North America and Europe.
Once again, it is clear how the United States coast is close to boiling over, providing fodder for ever more massive hurricanes that, in turn, also cost us billions in economic and ecological losses, not to mention human lives. The La Niña phenomenon and a record season as expected only add more reasons to be concerned, as the United Nations and the WMO are expressing these days.