Ocean heat, global temperatures continue to break records. What to expect?

For over a year, the ocean has consistently broken temperature records, and 2024 followed the trend of surpassing previous years by significant margins. 

According to the Copernicus Climate Change Service, last month saw the average global sea surface temperature reach a new monthly high of 21.07 degrees Celsius.

"March 2024 continues the sequence of climate records toppling for both air temperature and ocean surface temperatures," Samantha Burgess, deputy director of Copernicus, said in a statement this week.

The unusually warm temperatures in the tropical Atlantic are setting the stage for an active hurricane season, as forecasted by scientists at Colorado State University. 

Elevated ocean temperatures provide added energy, fueling the intensity of storms, they warned.

In fact, the whole planet has been hot for months.

The rise in global temperatures is attributed to the long-term effects of climate change, primarily driven by the emission of greenhouse gases from burning fossil fuels. 

So far, climate change has raised the global average temperature by about 1.2 degrees Celsius, or 2.2 degrees Fahrenheit, above the preindustrial average temperature. 

As it takes more energy to heat up water than air, the oceans have absorbed most of the planet's warming from greenhouse gases.

Gavin Schmidt, a climatologist and the director of the NASA Goddard Institute for Space Studies, emphasised the significance of this data, highlighting the importance of understanding the underlying physical processes to improve climate models and predict future temperatures accurately.

Compared with this time last year, what's different now is that the planet is dealing with the effects of an El Niño event that began in July. El Niño events are natural climate patterns associated with elevated temperatures.

Dr Schmidt told The New York Times, "The temperatures that we're seeing now, the records being broken in February and March, are actually much more in line with what we would expect" compared with those of last year. 

"Let's see what happens by the summer."

El Niño is weakening and expected to dissipate soon. What happens to global average temperatures then would help shed light on the temperatures of 2023, he said.

In addition to climate change and El Niño, a couple of other factors might be contributing to these dizzying records.

One contributing factor to the current temperature records is the reduction in aerosol pollution from container ships, following new international fuel standards implemented in 2020. 

Additionally, the eruption of the Hunga Tonga-Hunga Haʻapai volcano in 2022, though submerged, released significant amounts of water vapor into the atmosphere, amplifying the greenhouse effect.

It was the most explosive eruption since Krakatau, according to Sean Birkel, an assistant professor at the University of Maine Climate Change Institute, who created a climate data visualization tool called Climate Reanalyzer. 

He told NY Times the warming effect of the volcanic eruption has been larger than early estimates suggested, noting that the eruption may have affected atmospheric circulation and helped amplify the El Niño that developed in 2023. 

But, he added, more research is needed.

Dr Schmidt acknowledged that current estimates may not fully account for all contributing factors.

As scientists continue to analyse the data, Dr Schmidt anticipates that new findings will emerge in the coming months, shedding further light on the complexities of global climate dynamics.