2009/07/30

80m Sea Rise maps - Australia




Using Google Maps and the Sea Level Rise applet, the following maps show 80 metres of sea level rise.
Areas shaded red are those areas inundated. (Click on map symbol to see enlargements.) 


Australia

Adelaide




Detail of Porters Hill - the ridge keeping the ocean out of the Lake Eyre Basin.  About 4km, and only a few tens of metres above 80m.  
It won't last long.   Be there when that breaks through!


Melbourne


Sydney

Brisbane


I strongly recommend you check with your local maps to review the location of the 80 metre contour in your area of interest.

2009/07/29

Now: Why it's even worse than we feared.

In relation to the Science behind my estimates of sea level rise we can now add the information from an article by Sharon Begley at newsweek.com published 24 July 2009. Sharon pulls together some recent views on the state of the ice on and around Greenland. Read the article for the details.


http://www.newsweek.com/id/208164


Some quotes:


...the sea ice found a more open, ice-free, and thus faster path westward thanks to Arctic melting.


...The loss of Arctic sea ice "is well ahead of" what the Intergovernmental Panel on Climate Change forecast, largely because emissions of carbon dioxide have topped what the panel—which foolishly expected nations to care enough about global warming to do something about it—projected. "The models just aren't keeping up" with the reality of CO2 emissions, says the IPY's David Carlson.


... satellite measurements of Greenland's mass, show that it is losing about 52 cubic miles per year and that the melting is accelerating. So while the IPCC projected that sea level would rise 16 inches this century, "now a more likely figure is one meter [39 inches] at the least," says Carlson. "Chest high instead of knee high, with half to two thirds of that due to Greenland." Hence the "no idea how bad it was."


...estimates of how much carbon is locked into Arctic permafrost were, it turns out, woefully off. "It's about three times as much as was thought, about 1.6 trillion metric tons, which has surprised a lot of people," says Edward Schuur of the University of Florida. "It means the potential for positive feedbacks is greatly increased." That 1.6 trillion tons is about twice the amount now in the atmosphere. And Schuur's measurements of how quickly CO2 can come out of permafrost, reported in May, were also a surprise: 1 billion to 2 billion tons per year. Cars and light trucks in the U.S. emit about 300 million tons per year.


...the G8, led by Europe, has vowed to take steps to keep global warming below 2 degrees Celsius by reducing CO2 emissions. We're now at 0.8 degree. But the amount of CO2 in the atmosphere is already enough to raise the mercury 2 degrees. The only reason it hasn't is that the atmosphere is full of crap (dust and aerosols that contribute to asthma, emphysema, and other diseases) that acts as a global coolant. As that pollution is reduced for health reasons, we're going to blast right through 2 degrees, which is enough to ex-acerbate droughts and storms, wreak havoc on agriculture, and produce a planet warmer than it's been in millions of years.


...The test of whether the nations of the world care enough to act will come in December, when 192 countries meet in Copenhagen to hammer out a climate treaty. Carlson vows that IPY will finish its Arctic assessment in time for the meeting, and one conclusion is already clear. "A consensus has developed during IPY that the Greenland ice sheet will disappear," he says.


Now what happens to Greenland will also be mirrored in the Antartic, where as detailed in previous posts and below, the West Antarctic Ice Sheet is showing signs of distress. The combination serves to push the "Very Likely" sea level rise closer to two metres, and the possible worst case through my estimated five metres.


I insure my house against fire for the possible worst case. I don't know anybody who has had their house burned down, do you? But we all act to protect ourselves and our record collections against the conceivable worst case. Five metres is conceivable, and even more so in terms of these latest discoveries by the International Geophysical Year scientists.


We should act accordingly.

2009/07/13

The only number that matters...

My reason for hammering on about the two perils of sea level rise and resource depletion is that these will impose enormous demands on society to cope with - not the least being replacing coastal area's food production and the relocation of living places and critical infrastructure and production capacity to high ground. But as part of the attacking pincer movement we are exposing ourselves to, right when we need to start the biggest building effort the world has ever seen to get away from the coast we are running out of our primary energy source for construction.

Thus we only have a very short window of time (maybe 20 to 50 years at the most) to rebuild the fabric of our coastal civilisation someplace else before we run out of the energy we need to do that. And since we only have the time and resources to do this once. ONCE. Then we must do it where it will be SAFE from whatever is coming.

The level of the ocean at your place or mine in 2100 is irrelevant - it is just a marker on a journey to the finished level of +80 metres.

Eightly (80) metres of sea level rise is coming. We know this. This is the only number that matters. So we have a duty to only expend our diminishing resources ABOVE that level, or else with good cause our names will go down in infamy with our children and our grandchildren, 'yea unto the n-th generation'.

The simple point is that WE KNOW THIS IS GOING TO HAPPEN sooner or later. To pretend anything else is to deny our children what ever small chance at survival we can give them.

I want to be able to look my grandchildren in their eyes, and say "I knew, and I tried."

Nigel

2009/07/07

A sign!

Five degrees and five metres by 2100?

New information is suggesting that temperature rise may exceed current IPCC expectations. Five degrees Celsius is bound to give rise to more than just 2 metres sea level rise.

In my view, while 2 metres was strongly supported by people like Dr Hansen under 2008 Business as Usual scenarios, this recent information making it likely that we will get 5 degrees Celsius warming by 2100 leads me to recommend that we use the 5 metres by 2100 table and chart here as our basis for sign locations.

5 & 5 by 2100. Gulp!

This condition could give rise to accelerated ice loss, and hence sea level rise.

Thus by 'eyeometry' a curve fitted to past and expected long term SLR could entail this data:

DATE (YEAR AD)SLR (m)
18000
19000.02
20000.2
20250.5
20501.4
20752.9
21005
220015
230027
240040
250052
260059.5
270063.5
280066.5
290068.5
300070
310071
400075
500077.5

and look like this:


and in detail

(Click on images for enlarged view)

This could be a more realistic view of our imminent future to use in our depictions of the Sea Level Rise that is coming.

So find out how far above high water your site is, and interpolate values from the above table or charts to figure out what date to write on your sign.