Sea levels rising much faster than predicted

With most extra heat that is trapped in the atmosphere going into the oceans, how they react to it is critical. The heat leads to an expansion of the oceans, and consequently an increase in sea levels.  

Previous research has said that this “thermometer effect” has solely been responsible for sea levels rising by between 0.7mm and 1mm a year. But a team from the University of Bonn, in Germany, said this week that in the past 12 years, sea levels have risen by double that – 1.4mm a year. 

This conclusion was made after the team studied satellite data between 2002 and 2014. 

“To date, we have underestimated how much the heat-related expansion of the water mass in the oceans contributes to a global rise in sea level,” said Jurgen Kusche, a professor at the University of Bonn.

The United Nations’ own climate agency says the effect has seen a sustained increase in recent years, thanks to greenhouse gas emissions trapping more heat in the atmosphere and oceans. 

The overall impact of oceans is still not fully understood because they change temperature and levels slowly and over long time periods. But when ocean temperatures do change, they have a profound effect on weather systems. 

The current El Niño – which has rapidly warmed the Pacific Ocean by 3°C – has seen drought in the southern hemisphere and flooding in the northern hemisphere. It has also been linked to more intense storms and an increase in the intensity of other weather phenomena.  

Longer-term warming of the oceans is blamed for a multitude of problems, alongside the damage done by increased sea levels. Warmer oceans mean more energy for cyclones, which can also carry more water as a result of the heat.

In 2012, Hurricane Sandy passed over water that scientists said was 0.6°C hotter thanks to global warming, gaining energy and holding more water. It then hit the eastern coastline of the United States, where the sea levels were already higher thanks to overall ocean warming, and flooded cities such as New York.  

When combined with melting ice and other warming factors, the Bonn team found that the overall global sea level rise is 2.74mm a year. 


These are unprecedented times, and the role of media to tell and record the story of South Africa as it develops is more important than ever. But it comes at a cost. Advertisers are cancelling campaigns, and our live events have come to an abrupt halt. Our income has been slashed.

The Mail & Guardian is a proud news publisher with roots stretching back 35 years. We’ve survived thanks to the support of our readers, we will need you to help us get through this.

To help us ensure another 35 future years of fiercely independent journalism, please subscribe.

Sipho Kings
Sipho is the Mail & Guardian's News Editor. He also does investigative environment journalism.
Advertising

Where is the deputy president?

David Mabuza is hard at work — it’s just not taking place in the public eye. The rumblings and discussion in the ANC are about factions in the ruling party, succession and ousting him

Zuma turns on judiciary as trial nears

Former president says pre-trial correspondence is part of another plot

SANDF inquiry clears soldiers of the death of Collins Khosa

The board of inquiry also found that it was Khosa and his brother-in-law Thabiso Muvhango who caused the altercation with the defence force members

Lockdown relief scheme payouts to employees tops R14-billion

Now employers and employees can apply to the Unemployment Insurance Fund for relief scheme payments
Advertising

Press Releases

Covid-19 and Back to School Webinar

If our educators can take care of themselves, they can take care of the children they teach

5G technology is the future

Besides a healthcare problem Covid-19 is also a data issue and 5G technology, with its lightning speed, can help to curb its spread

JTI off to court for tobacco ban: Government not listening to industry or consumers

The tobacco ban places 109 000 jobs and 179 000 wholesalers and retailers at risk — including the livelihood of emerging farmers

Holistic Financial Planning for Professionals Webinar

Our lives are constantly in flux, so it makes sense that your financial planning must be reviewed frequently — preferably on an annual basis

Undeterred by Covid-19 pandemic, China and Africa hold hands, building a community of a shared future for mankind

It is clear that building a community with a shared future for all mankind has become a more pressing task than ever before

Wills, Estate Administration and Succession Planning Webinar

Capital Legacy has had no slowdown in lockdown regarding turnaround with clients, in storing or retrieving wills and in answering their questions

Call for Expression of Interest: Training supply and needs assessment to support the energy transition in South Africa

GIZ invites eligible and professional companies with local presence in South Africa to participate in this tender to support the energy transition

Obituary: Mohammed Tikly

His legacy will live on in the vision he shared for a brighter more socially just future, in which racism and discrimination are things of the past

The best local and international journalism

handpicked and in your inbox every weekday