Page 1 of 1

Sea level

Posted: 23 Jul 2011, 21:21
by biffvernon

sea level

Posted: 23 Jul 2011, 21:29
by ujoni08
Interesting.

Here's something related, just in over on The Huffington Post:

http://www.huffingtonpost.ca/2011/07/23 ... l?ir=Green

'THE CANADIAN PRESS — ST. JOHN'S, N.L. - The greatest iceberg season in recent memory is drawing scores of visitors to Newfoundland's northern peninsula for a glimpse of the majestic sculptures.

"For this time of year, I've never seen so many icebergs — and so big," said Paul Alcock of Northland Discovery Boat Tours in St. Anthony, N.L.

"It's a pretty spectacular sight out here right now," he said of at least 25 icebergs still looming within 16 kilometres of the town.

"For this time of year, you wouldn't expect to see much more than three or four."

The rare extravaganza is thanks to a nearby ice island that was part of a 260-square-kilometre chunk that split from Greenland's Petermann Glacier last August. That original piece has since broken into smaller bits.

One of the largest remaining pieces is the 50-square-kilometre ice island now floating about 20 kilometres off Labrador, south of Cartwright.

As it moves through the water, it "calves" or sheds pieces of ice that create the clusters of icebergs now attracting visitors from across Canada and parts of the U.S., Alcock said'.

Jon

temperature records across the US

Posted: 23 Jul 2011, 22:10
by ujoni08
Record temperatures recorded across the US:

http://www.treehugger.com/files/2011/07 ... normal.php

'In Matt's recent post on hot weather he reported that June Record High Temperatures Beat Record Lows 11-to-1 in US.

Yesterday, the 21st of July, it was hotter than hell across much of the Eastern US.

Nights, which tend to have the daily minimum, were especially unpleasant. Out of 5,569 daily minimums recorded on the 21st, 188 broke previous records and another 138 tied them (exceeding or equaling, respectively, the previous record for daily minimum temperature)'.

Jon

Posted: 23 Jul 2011, 22:21
by biffvernon
Hotter than hell? What are the Christian fundamentalist AGW deniers going to make of that?

context

Posted: 23 Jul 2011, 22:22
by ujoni08
http://www.treehugger.com/files/2011/07 ... n-past.php

'This time, the extreme drought, heat, and wildfires are occurring along with US extremes this year in rainfall, snowfalls, flooding, and tornadoes, and many other stunning temperature and precipitation extremes elsewhere in the world in recent years as well as, as I posted on my TWC Facebook "fan" page, record-shattering 500 millibar heights in lattitudes. And all of this is happening while there's an alarming drop in the amount of Arctic sea ice.

The nature and context of the extremes is the difference between the 1930s and now'.

Jon

Posted: 02 Aug 2011, 00:39
by RenewableCandy
biffvernon wrote:Hotter than hell? What are the Christian fundamentalist AGW deniers going to make of that?
Why take all the trouble to send them to hell when it's easier to bring hell to them :) ?

Posted: 25 Aug 2011, 10:56
by An Inspector Calls
This will make the UN's job of sea level rise/fall prediction even harder:

http://www.jpl.nasa.gov/news/news.cfm?release=2011-262

Nasa desribes this blip as a pothole. As it's the biggest fall in sea level since 1992 (or Nasa's plot range) perhaps it should be considered more a chasm.

I thought sea level rise was supposed to be accelerating?

Another global warming proxy bites the dust.

Posted: 25 Aug 2011, 11:20
by Bandidoz
An Inspector Calls wrote:Another global warming proxy bites the dust.
That's surprising coming from someone who professes to belong to scientific and engineering institutions.

Let's see if that trend continues for the next 5 years? If so then you can declare that it's bitten the dust...

Posted: 25 Aug 2011, 12:00
by clv101
An Inspector Calls wrote:Another global warming proxy bites the dust.
Didn't we have this discussion a few months ago? SLR is a function of many processes, influencing mass, temperature and salinity. The very article you link to is clear about the increased continental rainfall transferring mass from oceans to land. That process does nothing to weaken the relationship between sea level and global warming. To say anything sensible about either, you need to unpick all the contributing processes, not just compare the aggregate.

Posted: 25 Aug 2011, 12:10
by DominicJ
So,
sea level rise = global warming
sea level fall = weather
?

Posted: 25 Aug 2011, 12:35
by clv101
DominicJ wrote:So,
sea level rise = global warming
sea level fall = weather
?
If that it were that simple! :)

Sea level rise = sum(mass balance and density change) > 0
Sea level fall = sum(mass balance and density change) < 0

There are lots processes that affect the these eustatic and steric components including some that are to do with global warming (like temperature increase and melting of grounded ice) and some that probably aren't, or at least aren't permanent (like rainfall migrations).

It's quite possible for ocean temperature to increase (decreasing density and increasing volume), for grounded ice mass to decrease, putting more water into the ocean and for increased continental rain to move a greater than compensating volume of water from the ocean onto the land causing a net lowering in sea level.

These processes can all be independently observed so we don't have to draw simple conclusions from the aggregated sea level rise signal, losing information in the process.

Posted: 25 Aug 2011, 14:13
by biffvernon
The March 11th Earthquake caused a rise in sea level, or a drop in land level, depending on one's point of view, of almost a metre along the eastern shores of Japan. And that probably had nothing to do with climate change.

Posted: 25 Aug 2011, 14:26
by clv101
Of course people normally talk about the global average sea level. In any specific place, the actual average level of the sea can go up or down by a large amount. For example - melt ice in Greenland, the mass and volume of the ocean increases, however, the sea level in the North Atlantic goes down because the gravitational attraction of the Greenland ice sheet decreases.

Posted: 26 Aug 2011, 09:11
by An Inspector Calls
But sea level rise is supposed to be accelerating caused by global warming. clv101 can protest all he likes about the complexity of the record (which makes the observation a stupid proxy for global warming in the first place), but it's the CAGW camp that claims that sea level rise is a usable proxy.

http://www.wmo.int/pages/prog/wcrp/docu ... 080221.pdf
(Of course, these people were simply comparing the aggregate! Don't you love the straight line drawn through the last decade's records to prove that sea level rise is accelerating? Just a tad selective of start and end points, perhaps. Used to use that trick at school).

As I pointed out, Nasa says this is a blip, probably is, ( :wink: Bandidoz), but it does ruin this man's position:

http://thinkprogress.org/romm/2011/03/1 ... t-by-2050/

So it somewhat weakens the position of sea level as a proxy for global warming. Church's straight line is now ruined!

As for sea dropping because the water has been transferred to the land masses: since sea level's dropped by 6 mm, and the ratio sea:land area is 70:30, that means that the average depth (obviously, now possibly in groundwater) on land is 14 mm in a year. Does that seem plausible to everyone? Doesn't to me. And GRACE is reporting groundwater depletion.