Monday, April 01, 2013

The Sea Is Not Flat

One of the surprising things is that the sea is not flat, but there are places where sea level is lower than others, rising faster than others or slower.  Mostly bunnies just look at the averages, but the money, just as with temperature and precipitation changes is local.

Turns out that the northeast US coast, from Cape Hatteras on north up to Maine is the so called Northeast Hot Spot (NEH) and the rate of sea level rise since 1950 or so is three times the global. Sallenger Doran and Howd explore the "Hotspot of accelerated sea level rise on the Atlantic coast of North America".  Turns out it's not all bad news because

In the late twentieth century, sea levels were relatively low along the North American east coast, particularly north of Cape Hatteras8,9. Sea-surface gradients sloped down towards the coast away from the Gulf Stream and its continuation to the northeast, the North Atlantic Current10. The sharp pressure gradients balance the Coriolis force to sustain these narrow and strong geostrophic currents, leading to low coastal sea levels.
But the recent rate of change in this area is large.  The figure to the left shows the Sea Level Rise Differences from 1970-2009 along the coast, that on the right shows the SLRD time series for start years from 1894 to 1970.  The former has a length of 115 years, the latter 40 years.


20 comments:

Susan Anderson said...

former ... latter ... is that backwards?

Anonymous said...

Dr. Lumpus Spookytooth, phd.

where's the post about your boy gambino taking on the mighty McIntyre? Oh right, you gave up defending the Marcott study because McIntyre so thoroughly demolished it. So here's the question? Why does the alarminati keep making temperature reconstructions showing current temps warmer than the Roman and Medieval Warm periods? I wonder if it has anything to do with the fact that there was far less co2 in those times, and it wrecks the narrative.

owning the alarminati never felt so good.

Brad Keyes said...

Dear Susan, dear Lumpus,

If you ever do find that post, please link us to it—I'd enjoy watching Susan go out on a limb for Marcott! LOL

Brad Keyes said...

Lumpus,

the narrative utility of the idea that modern temperatures are somehow unprecedented should be self-explanatory.

That, in turn, is the motive force behind climate change denial (a phenomenon in which grown men and women pretend there was no MWP, no LIA, etc.).

a_ray_in_dilbert_space said...

Enjoy your delusion, Lumpus. Enjoy your delusion.

It's going to be fun to watch the reaction of the denialati when Marcott continues to stand despite the efforts of the frauditors.

EliRabett said...

Here is a reading list for lumpy

Jos Hagelaars on Our Changing Climate

Tamino on Global Temperature Change - the Big Picture

Tamino on the tick

Tamino on Regional Marcott

Tamino on Steve's Hissy Fit

Nick Stokes on My limited emulation of the Marcott reconstruction

Nick Stokes on Next stage of the Marcott et al study

Nick Stokes on An active Viewer for Marcott et al

Nick Stokes on Proxy viewer with choice of dating and range

Go get em scout

Sou said...

There are different patterns of sea level rise around Australia, too. IIRC right down south it's not so fast but as you go further north in some parts the sea level is rising faster.

BTW Eli, is it time yet?

Kevin O'Neill said...

Brad Keyes - science tells us that throughout most of the Cenozoic era global surface temperatures have exceeded modern temperatures. This is especially true for the Arctic. During the Pliocene arctic temperatures may have been as much as 19C warmer than today.

More recently we have evidence of driftwood and beach ridges that formed during the Holocene Climate Optimum. These facts are known to anyone that studies climate. So your notion that those who study climate claim recent warming is "unprecedented" is either poorly worded or just hogwash.

Of course in more recent human history the warming probably *is* unprecedented. For centuries europeans sought in vain for a Northwest or Northeast passage through the Arctic Ocean. Many spent years caught in the ice and dozens if not hundreds died seeking a navigable route. Today that passage has been made rather routine because of this:

SIE 1982 vs 2012

Anonymous said...

Dr. Lumpus Spookytooth, phd.

@kevin O'Neill

well said. The side arguing for a high climate sensitivity keeps saying that it is only important to study temperature and co2 in reference to humankind's existence. But that is not objective. We have to be looking at earth's temperature and co2 fluctuations since the time of the dinosaurs. I strongly believe in using running averages.

@eli

I will look into all the links you posted above. I am trying to be more open minded, and no I'm not saying that to jag Tamino but I am still mad at him for never posting my comments.

Anonymous said...

We already know that it's the land that is rebounding along the coast where there was once a very heavy glacier. That would explain the map.

Hardy Cross

BBD said...

@ Hardy Cross

Look! A horse!

http://tamino.wordpress.com/2012/12/18/horseshit-power/

metzomagic said...

Complementing Eli's post, a must-watch video that explains why sea level ain't the same across the globe. Not even close:

http://www.skepticalscience.com/Jerry-Mitrovica-Current-Sea-Level-Rise-is-Anomalous-Weve-Seen-Nothing-like-it-for-the-last-10000-Years.html

I see Lumpy is doing what he does best: pointing at squirrels. Sure seem to be a lot of 'em round here lately.

David B. Benson said...

No MWP to be found in the James Ross Island ice core proxy.

So not global.

Brad Keyes said...

Kevin:

"So your notion that those who study climate claim recent warming is "unprecedented" is either poorly worded or just hogwash."

Oops. Poorly worded, and therefore hogwash.

What I should have said was that they seek to portray it as "unprecedented" in human memory, the Christian Era, the last millennium, the last 250 years, or whatever time period they can get away with, including vague and mustelistic intervals like...

"Of course in more recent human history the warming probably *is* unprecedented."

Unknown said...

Glad to see this post! The "bumpiness" of the ocean is an even bigger issue in the Pacific. There's large variation in rates of sea level rise, not to mention, natural variability, some related to climate oscillations. A student edited together this little video of how the sea level "noise" affects Kiribati, from video and images I'd collected over the years doing research there.

Miguelito said...

I read the title as "The seal is not fat" and wondered if Eli had picked up a new moniker for McIntyre or either of the Pielkes.

Anonymous said...

Spaaangled Drooongo...

(Hot potato, orchestra stalls, Puck will make ammends...)

Bernard J.


[I think, therefore I am not a robot.

QED.]

Steve Bloom said...

Lumpus: "The side arguing for a high climate sensitivity keeps saying that it is only important to study temperature and co2 in reference to humankind's existence."

Try the exact opposite, Lumpus. The case for high sensitivity is mostly deep-time paleo.

Re Tamino, he has little tolerance for bullshit, and your chosen handle alone would trip that lever.

a_ray_in_dilbert_space said...

Steve,
I still think Lumpus is a dinosaur that somehow missed out on the extinction and is arguing for a return to the Jurassic.

Hank Roberts said...

Russell identified Spooky as that Forbes staff member, I think.

On sea level, above I read
"sharp pressure gradients balance the Coriolis force to sustain these narrow and strong geostrophic currents, leading to low coastal sea levels."

Does a slowing of the thermohaline circulation lower the height of the Gulf Stream?