Ocean temperatures reached a near-record high in March, the European Union’s global warming monitor, Copernicus Climate Change Service, said Friday.
The warmest March for the oceans on record was in 2024, during which the El Niño climate cycle increased temperatures. Current records once again show a “possible transition toward El Niño conditions,” Copernicus said.
Last month, the World Meteorological Organization (WMO) had similarly predicted a change in the cycle this year. The organization predicts a cooler La Niña cycle will give way to neutral conditions before turning into El Niño later this year.
America records hottest March in 130 years
Last month was the unusually warmest month in the US in 132 years of records, according to federal weather data.
“One reason that’s so worrisome is the sheer volume on record. This is coming after the worst snowfall year on record and the warmest winter on record,” Shel Winkley, a meteorologist at the nonprofit Climate Central, was quoted as saying by the Associated Press.
According to Climate Central’s calculations, on March 20 and 21, nearly one-third of the US experienced unseasonable heat that would have been nearly impossible without human-caused climate change.
Following the 2015 Paris Agreement, countries agreed to limit near-surface temperatures to 2 degrees Celsius. A more ambitious target of 1.5°C was set to avoid the worst effects of global warming. In recent years, global surface air temperatures have risen between 1.3°C and 1.4°C since the pre-industrial era, according to the European Union’s monitor Copernicus.
Understanding La Nina and El Nino
La Niña and El Niño are opposing climate cycles in the tropical Pacific Ocean that cause short-term temperature fluctuations on a global scale. El Nino conditions increase heat extremes on an already warming planet. The most recent El Niño in 2023–2024 contributed to making those years the second warmest and warmest on record, respectively.
The EU’s Copernicus climate change service said Friday that in the Arctic, sea ice levels were 5.7% below average for March, the lowest on record for the month.
The area of ocean covered by ice has been steadily decreasing year-on-year, a key indicator of rapid warming in the Arctic and Antarctica.
Consequences of warming the oceans
The oceans are the planet’s hot spots. They absorb most of the excess heat caused by human activities and therefore play an important role in regulating the global climate.
Warming oceans could have harmful effects on the planet. Their size increases due to thermal expansion. Furthermore, they accelerate the melting of the Arctic which contributes to sea level rise. Additionally, warmer oceans promote stronger storms and rainfall, both of which have become more frequent in recent years.
Edited by: Kieran Burke