Ancient warm period hints at bigger-than-expected sea level rise

[webfact]

Ancient warm period hints at bigger-than-expected sea level rise

By Alister Doyle

 

OSLO (Reuters) - Sea levels could rise by a greater-than-expected six metres (20 ft) over many centuries even if governments cap global warming around current levels, scientists said on Thursday, based on clues from an ancient warm period.

 

Sea levels have risen by about 20 cms (8 inches) in the past 100 years, with a thaw of ice from Greenland to Antarctica spilling water into the oceans. Many studies have assumed that rising temperatures are a condition for a much faster melt.

 

A study in the journal Science, however, said sea temperatures in a natural warm period about 125,000 years ago were "indistinguishable" from today, rather than up to 2 degrees Celsius (3.6 Fahrenheit) hotter as previously thought.

 

"The trend is worrisome as sea levels during the last interglacial period were between six and nine meters (20-30 ft) above their present height," Science said of the findings led by Jeremy Hoffman at Oregon State University.

 

The experts studied deep seabed sediments, containing chemical signals of temperatures, at 83 sites. It can take centuries or thousands of years for rising temperatures to thaw vast ice sheets.

 

"The study suggests that, in the long term, sea levels will rise 6 metres at least in response to the warming we are causing," said Andrew Watson, a professor at Britain's University of Exeter who was not involved in the research.

 

"The good news is that with luck it will continue to rise slowly so that we have time to adapt, but the bad news is that eventually all our present coastal city locations will be inundated," he wrote in a comment.

 

Anders Levermann, a professor at the Potsdam Institute for Climate Impact Research, said the study was a hint both that ice sheets would melt at lower temperatures than previously expected and also more rapidly.

 

"It could mean that sea levels will respond faster" to global warming, he told Reuters. He added that there were still many uncertainties about inferring rates of sea level rise from the pre-historic temperatures.

 

On Wednesday, the U.N.'s World Meteorological Organization said that average global surface temperatures hit a record high in 2016 for the third year in a row and were 1.1 degree Celsius (2.0°F) higher than in pre-industrial times.

 

(Editing by Gareth Jones)

 

-- © Copyright Reuters 2017-01-20

[thaibeachlovers]

Shock horror, hold the press! It was warmer a long time ago and humans were not around to make it happen- how could that be??????

[Calach]

The sooner the better, hopefully Bangkok will be submerged and my office relocated to Chiang Mai. 

[fvw53]

1 hour ago, thaibeachlovers said:

Shock horror, hold the press! It was warmer a long time ago and humans were not around to make it happen- how could that be??????

 

never heard about volcano's?

[canuckamuck]

Now's the time for buying pre coastal land on spec. 

 

[AgMech Cowboy]

8 hours ago, Calach said:

The sooner the better, hopefully Bangkok will be submerged and my office relocated to Chiang Mai. 

 

You're obviously not a home owner in this river valley.   Lucky man. We'll never get the value out that we've put in. 

Edited January 20, 2017 by AgMech Cowboy
left out 'not' a home owner...

[maoro2013]

Depends what years are used to work out temperature increase or decrease.

 

The world has actually cooled if you pick the right years.

 

Personally I need a lot more convincing about the whole thing, and particularly man's role in this, possible, problem.

 

I have seen and heard so many blatant lies about the whole thing I am not convinced at all.

[johng]

Shock horror, hold the press! It was warmer a long time ago and humans were not around to make it happen- how could that be??????

must have been all those dinosaurs breathing and farting.

or maybe the energy output from the sun varies over time ?

[canuckamuck]

It has been naturally warm before. Much warmer and much quicker.

But if I say the current minor temperature change, barely a degree in 100 years and almost imperceptible increase in the last 20 is not primarily caused by humans, then I am a flat-earther.

This is the state of scientific discussion in the 21st century.

[piewarmer]

Man is just making it happen faster than nature. Don't worry, we won't be here when it gets ugly.

[jcsmith]

19 hours ago, thaibeachlovers said:

Shock horror, hold the press! It was warmer a long time ago and humans were not around to make it happen- how could that be??????

 

There's a big difference between natural warming and man made warming. We are rapidly accelerating the process, and adding to what would have naturally occurred. CO2 levels are higher now than they have been in at least 400,000 years, and growing at an accelerating rate.

[Panda13]

Sent from my SM-G930F using Thaivisa Connect mobile app

[piewarmer]

20 hours ago, thaibeachlovers said:

Shock horror, hold the press! It was warmer a long time ago and humans were not around to make it happen- how could that be??????

faceplant!,  they walk among us.

[impulse]

19 hours ago, canuckamuck said:

Now's the time for buying pre coastal land on spec. 

 

Or just quit mucking about and buy a liveaboard now and get yourself conditioned.  Then you don't have to worry about how high it's going.  Just how to keep friends, family, hangers-on (and bad guys) from moving in with you.

[kannot]

22 hours ago, fvw53 said:

 

never heard about volcano's?

its  been  far  far  hotter  for  far  far  longer and  happened far  far  faster  than  now.....excuse  my  sturrrrrr sturrrrrrr stutter

Edited January 21, 2017 by kannot