2019/03/05

Global Mean Sea Level data and CO2 level update.

A great source of mean sea level data is now presented at: Sea Levels . Org.



This confirms the trends we estimated a decade ago, with what appears to be almost an exponential trend from 1900 through today.

I see too that the Global monthly mean CO2 levels are now at 408.16 ppm compared with 405.49 ppm this time last year.




Nothing to be complacent about here.

N

2016/07/14

Great sea-level rise maps re New Zealand

New Zealand Sea Level Rise
A series of maps depicting New Zealand in various sea-level rise scenarios

A wonderful resource Jonathan has put together.
Review, and ponder!

2015/04/14

'...the future course is being prepared for a 70 meter rise in sea level.'

Read the last line first...

Andy Lacis responds to Steve Koonin 



'...Physicists should not be confused by these random-looking quasi-chaotic fluctuations about the local climate equilibrium point, and should instead focus more on the changing energy balance equilibrium point of the climate system. They should also pay attention to the geological record that points to an atmospheric CO2 level of 450 ppm as being incompatible with polar ice caps, a level that is expected to be reached by the end of this century. While it may take a thousand years for the polar ice to melt, the future course is being prepared for a 70 meter rise in sea level.'

2014/08/01

Time to break out the gum boots?

This just in from Arctic News
...2.5m Sea Level Rise by 2040???

'A polynomial trendline applied to the data points at a sea level rise of more than 2.5 m (8.2 ft) by the year 2040. ..'

The analysis considers whether the trend in increase in sea levels should be considered as linear (same amount next year as last year) or polynomial (more next year than last year, and more again the year after).  The conclusion appears to be that the rate of rise will continue to increase, leading to the conclusion that SLR will get to 2.5 meters by 2040, and of course it will continue to behave exponentially until a balance is achieved between the amount of grounded ice left to melt and the rising global air and sea temperatures, when the rate of rise will fall back to zero when the last ice block is melted in a world that is somewhere between two and five (God help us!) degrees warmer than today. 

Hansen a while back (2011) discussed doubling times of the observed sea level rise and showed how (like compound interest) this would predict a rise of 5 metres by 2100 .

This new work suggests that with 'business as usual warming (including the accelerated warming the polar areas are experiencing - they always get more than their fair share of the additional heat - the sky is the limit for global temperatures, and with those temperatures comes faster melt, as well as all the other interesting side effects of a more energetic climate.

As evidence of those unfortunate effects we have an airliner at cruising altitude taken out and destroyed, by the weather.  A sad pointer to times to come.  And another.

(As part of preparations, and recognising the weather we are getting already, I'm working on plans for a storm-proof greenhouse, as we just lost a lot of seedlings due to storm and we don't want that to happen again.)

Keep up the great work!
N  

2014/07/08

Recent research. The outlook is not improving.

To set the scene:-

401.30ppm


Atmospheric CO2 for June2014

And now, the news...

1.
Antarctic glaciers melting twice as fast as previously estimated: scientists

English.news.cn   2014-07-08 09:03:09

http://news.xinhuanet.com/english/sci/2014-07/08/c_133467402.htm

'..sub-surface ocean temperatures down to 700 meters are rapidly changing around Antarctica because of shifting wind patterns, thought to be partly due to global warming.
"It certainly was for me a very frightening result," Spence said.'
"It's not unlike an avalanche of snow, where you don't quite know when it's going to happen but when it happens, it can happen quickly," Spence said.
The Australian Antarctic Division's Tas van Ommen said the effects of a rapidly transforming Antarctica are now likely to be felt this century.
--
2.
The runaway glaciers in West Antarctica 
http://climatestate.com/2014/07/05/the-runaway-glaciers-in-west-antarctica/
NASA/JPL press release, May 12, 2014: A new study by researchers at NASA and the University of California, Irvine, finds a rapidly melting section of the West Antarctic Ice Sheet appears to be in an irreversible state of decline, with nothing to stop the glaciers in this area from melting into the sea.
“The collapse of this sector of West Antarctica appears to be unstoppable,” he said. “The fact that the retreat is happening simultaneously over a large sector suggests it was triggered by a common cause, such as an increase in the amount of ocean heat beneath the floating sections of the glaciers. At this point, the end of this sector appears to be inevitable.”
--
3.
Global warming and the vulnerability of Greenland's ice sheet
http://www.skepticalscience.com/global-warming-vulnerability-greenland-ice-sheet.html
...The level our oceans will rise to in the next decades and centuries depends strongly on how fast the Greenland ice sheet will melt.
Aside from the importance of deep troughs to ice motion, the extension inland means that glaciers will have to retreat further than anticipated inland in order to reach a position above sea level. “Some of them will stay in contact with the ocean for centuries, when we thought that in a couple of decades they would stabilize.” said Mathieu Morlighem.
The ice sheet is therefore more vulnerable than predicted, and existing projections of sea level rise contribution from Greenland are too conservative and need to be revised.
As the authors state in the paper, “Our findings imply that the outlet glaciers of Greenland, and the ice sheet as a whole, are probably more vulnerable to ocean thermal forcing and peripheral thinning than inferred previously from existing numerical ice-sheet models.”
--
4.

Mercury Rising: 2014 Sees Warmest May Ever Recorded Following on From 2nd Warmest April

Posted on 1 July 2014 by Rob Painting

http://www.skepticalscience.com/Mercury-Rising-2014-Sees-Warmest-May-Ever-Recorded.html
...with April 2014 being the 2nd warmest in 135 years of measurement (tied with 1998), and May 2014 the warmest ever in 135 years. 
2014 is currently on track to be one of the warmest years ever recorded, perhaps even the warmest. 
--/--


2014/05/29

Yup. It's happened before: One metre every 20 years... As I was saying...

http://www.climateoutcome.kiwi.nz/blog/rising-sea-levels-from-melting-ice

'When the planet moved from the last ice age to the present warm period  around fourteen thousand years ago there was a sudden increase in sea levels which amounted to twenty metres over four hundred years or, five metres  a century or, one metre every twenty years.'

And today...

'...six glaciers around Pine Island [Antarctica] ... the grounding line ... has been retreating towards the land at up to thirty five kilometres  (twenty two miles) a year. '

What price coastal properties now then?