Rising seas to hit tropics hardest

Feb 19, 2013 by Alex Peel
Rising seas to hit tropics hardest

Sea levels around the equator will rise up to 150 per cent more than the global average by 2100, new research reveals.

The study, published in , highlights the vulnerability of low-lying populations throughout the tropics, including western Australia, Hawaii and the islands of the South Pacific.

'We are successful in defining the patterns, known as sea level fingerprints, which affect sea levels,' says Professor Giorgio Spada of Italy's University of Urbino, who led the study.

'This is paramount for assessing the risk due to inundation in low-lying, densely populated areas.'

It has long been known that sea levels change by different amounts in different places.

But this research is the first to detail what those changes will look like as the oceans react to our .

The team, including two researchers from the Bristol University's centre, used computer models to investigate three key influences over the global pattern of sea-level rise.

At the end of the 10,000 years ago, billions of tonnes of melted from Earth's polar regions, lifting an enormous weight from the rocks beneath. The Earth's surface has been slowly rebounding ever since, causing some regions to emerge from
the sea while others subside.

The sheer mass of the remaining ice sheets gives them a strong , sucking in the seas around them like a giant plunger. As those ice sheets melt, the plunger will be released and the water redistributed around the globe.

As the oceans warm, they will also expand. Complex weather and climate patterns will mean that some areas will warm and expand more than others.

'The most vulnerable areas are those where the effects combine to give sea-level rise that is significantly higher than the global average,' says Spada.

'The total rise in some areas of the equatorial oceans worst affected by the terrestrial ice melting could be 60 centimetres if a mid-range sea-level rise is projected, and the warming of the oceans is also taken into account.'

For Europe, it means that sea levels will continue to rise, but by slightly less than the global average.

According to the 2007 Intergovernmental Panel on Climate Change (IPCC) report, the effect of melting ice was the largest remaining source of uncertainty in predicting sea-level rise.

This work was part of the ice2sea project, led by the British Antarctic Survey's Professor David Vaughan, which is attempting to address that uncertainty.

'In the last couple of years, programmes like ice2sea have made great strides in predicting global average sea-level rise,' says Vaughan.

'The urgent job now is to understand how global rise will be shared out around the world's coastlines.'

'Only by doing this can we really help people understand the risks and prepare for the future.'

The research will contribute to the new IPCC assessment of the state of the Earth's climate, which will begin to emerge later this year.

Explore further: Magnitude-7.2 earthquake shakes Mexican capital

More information: Spada G, Bamber JL, Hurkmans RTWL, The gravitationally consistent sea-level fingerpring of future terrestrial ice loss, 2013, Geophysical Research Letters, doi:10.1029/2012GL053000

Related Stories

Flow of research on ice sheets helps answer climate questions

Feb 16, 2013

Just as ice sheets slide slowly and steadily into the ocean, researchers are returning from each trip to the Arctic and Antarctic with more data about climate change, including information that will help improve current models ...

Sea level rise of 1 meter within 100 years

Jan 08, 2009

New research indicates that the ocean could rise in the next 100 years to a meter higher than the current sea level - which is three times higher than predictions from the UN's Intergovernmental Panel on Climate ...

Auditing the Earth's sea-level and energy budgets

Nov 04, 2011

An international research team has balanced the sea-level rise budget by showing that the total amount of contributions to sea level rise explains the measured rise over recent decades.

Recommended for you

Magnitude-7.2 earthquake shakes Mexican capital

Apr 18, 2014

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

User comments : 7

Adjust slider to filter visible comments by rank

Display comments: newest first

Lurker2358
3.4 / 5 (5) Feb 19, 2013
'The total rise in some areas of the equatorial oceans worst affected by the terrestrial ice melting could be 60 centimetres if a mid-range sea-level rise is projected, and the warming of the oceans is also taken into account.'


Makes no sense. according to every piece of data I've seen, the global average is already increasing by 3.1 centimeters per decade, and the rate of increase is increasing exponentially. At 50% more than the linear projection of this trend would already get you to 45 centimeters by a century's time, soconsidering the trend is not linear, but exponential, then getting a rise of 60 centimeters would actually be incredibly easy, and is likely an under-estimate by a factor of at least 2 to 4 times...
Shootist
2.2 / 5 (10) Feb 19, 2013
Bloody hell. What did the tropics do one thousand years ago? Ten thousand? A million?

"The polar bears (and the proboscis monkey) will be fine." Freeman Dyson.
Maggnus
3.8 / 5 (10) Feb 19, 2013
Only someone like shootist can look at report after report, all arriving at the same general conclusion, and yet stubbornly remain entrenched in an increasingly foolish and unsupportable position.
Lurker2358
3.8 / 5 (10) Feb 19, 2013
Bloody hell. What did the tropics do one thousand years ago? Ten thousand? A million?

"The polar bears (and the proboscis monkey) will be fine." Freeman Dyson.


yeah, well, NOLA, Miami, the Keys, and Galveston WON'T be fine.

Sea level in and around Florida has supposedly changed by both plus and minus several meters in the past million years or so, with coral reef fossils existing both well inland, and well off shore in places currently too deep to support this type of coral life.

Salt water intrusion will destroy many existing habitats, as well as human civilizations, and may threaten many species with extinction.

If the U.S.' average summer time day time high rises by the 6C/11F* it is currently forecast to rise by 2100, I can assure you world food supplies and industrial capabilities will be crippled. The U.S. will have trouble feeding itself, nevermind shipping free food to "poorer" countries...as is the current practice.

*The global annual rise projection is 4C.
Caliban
5 / 5 (3) Feb 19, 2013


Makes no sense. according to every piece of data I've seen, the global average is already increasing by 3.1 centimeters per decade, and the rate of increase is increasing exponentially. At 50% more than the linear projection of this trend would already get you to 45 centimeters by a century's time, soconsidering the trend is not linear, but exponential, then getting a rise of 60 centimeters would actually be incredibly easy, and is likely an under-estimate by a factor of at least 2 to 4 times...


Lurker,

You may want to have another look --I don't think that anyone has made a claim of "exponential" increase sealevel rise. Many say "accelerated" ice-mass loss, but that isn't the same as exponential. 60 cm is a pretty solid midrange figure for tropical sealevel increase, if you accept the current projected range of values predicted for ice-mass loss and thermal expansion contributions to sealevel increase.

VendicarE
3 / 5 (4) Feb 20, 2013
1,000 years ago, temperatures were somewhat cooler than today, but only marginally so.

Ten Thousand years ago, the earth had just entered the current interglacial.

A million years ago, Global temperatures were several degrees cooler than today.

"What did the tropics do one thousand years ago? Ten thousand? A million?" - ShooTard

Do you have any more questions?

runrig
3 / 5 (4) Feb 20, 2013
Bloody hell. What did the tropics do one thousand years ago? Ten thousand? A million?

"The polar bears (and the proboscis monkey) will be fine." Freeman Dyson.


Is Mr Dyson an omniscient sage?
Here in the UK he makes vacuum cleaners.

More news stories

China says massive area of its soil polluted

A huge area of China's soil covering more than twice the size of Spain is estimated to be polluted, the government said Thursday, announcing findings of a survey previously kept secret.

UN weather agency warns of 'El Nino' this year

The UN weather agency Tuesday warned there was a good chance of an "El Nino" climate phenomenon in the Pacific Ocean this year, bringing droughts and heavy rainfall to the rest of the world.

Growing app industry has developers racing to keep up

Smartphone application developers say they are challenged by the glut of apps as well as the need to update their software to keep up with evolving phone technology, making creative pricing strategies essential to finding ...

Making graphene in your kitchen

Graphene has been touted as a wonder material—the world's thinnest substance, but super-strong. Now scientists say it is so easy to make you could produce some in your kitchen.