Ocean heat breaks records


Electric car incentives are one way to help reduce carbon emissions. Picture credit: Red dot, Unsplash

Greenhouse gas concentrations and the heating, acidifcation and rise in the world’s oceans smashed the recrod books again in 2021, according to the World Meteorological Organization.

Australian National University climate change insistute head Professor Mark Howden said the record-breaking events make reversing the effects of climate change even harder.

“As climate change accelerates, the menu of options decreases and the effectiveness of those options decreases,” Prof Howden said.

Prof Howden is also part of the Intergovernmental Panel on Climate Change, a United Nations body set up to advise about climate change.

He says that the latest WMO report is unsurprising given that countries have been slow to adapt to climate change despite decades of warning about its effects.

While 2021 was not the warmest year on record due to a La Nina event, “the past seven years have been the warmest seven years on record,” the WMO say.

The IPCC released its Working Group III report in April and it details how the next few years are critical for climate change.

On reversing some of the damage from CO2, the first thing that needs to happen is a serious reduction in CO2 emissions, Prof Howden said.

The WMO says carbon dioxide needs to be taken out of the atmosphere to roll back any of the effects coming from the four record breakers of 2021.

There is so-far little known about man-made carbon capture and storage technologies.

“We’d need to plant up a whole area of Australia scattered around the world to make a big dent in the greenhouse emissions,” Prof Howden said.

The oceans soak up a quarter of the CO2 in the atmosphere, and last year’s record setting ocean acidification level means the ocean will struggle to soak up any more.

University of Tasmania oceanographer Professor Peter Strutton said despite emissions in 2021 being reduced compared to recent years, overall, emissions are still increasing and placing a heavy burden on the Earth’s climate systems.

“The oceans are absorbing a lot of heat due to climate change, if it weren’t for the oceans, the atmospheric heat that we’re already experiencing would be a lot higher, ” Prof Strutton said.

Oceans take up about a quarter of the CO2 in the atmosphere and when they take up too much they become more acidic – this leads to coral bleaching.

“It effects the plants and animals in the ocean (by) changing their distribution.

“In Tasmania we’ve seen an expansion of species from the north coming closer than they ever have before,” Prof Strutton said.

When CO2 seeps into the ocean it takes about a thousand years to cycle through and make its way out.

“If we stopped emitting tomorrow, there’s still a lot of processes that will continue,” Prof Strutton said.

To curb further damage done to the climate, well designed policy packages are needed to reduce emissions, Prof Howden says.

Policy packages, such as car emission standards paired with cheaper electric vehicles would be the easiest ways for the government to make an impact, he said.

“We need to find a way to put a price on greenhouse gases.”