The rate of Climate bSea level rise .

By steven d keeler | Mar 29, 2014

 

Nature Climate Change :  The rate of sea-level rise .

 

... However, over the last decade a slowdown of this rate, of about 30%, has been recorded  It coincides with a plateau in Earth’s mean surface temperature evolution, known as the recent pause in warming.  Here we present an analysis based on sea-level data from the altimetry record of the past 20 years that separates interannual natural variability in sea level from the longer-term change probably related to anthropogenic global warming. ...

 

From the Blog sphere, Hoser responds :

A long time ago in high school physics we became acquainted with the concept of the “universal-constant variable fudge factor” (U). When you boil it down, it’s just the ratio of expected results (X) to observed results(O), or U = X/O. When you just "know" something is true, you don’t have to put up with pesky experimental noise. You can never be disappointed, at least initially, when your final result (F) is simply F = O*U. That was a very good lesson. Knowledge of the process has served us well, helping us keep an eye out for people using similar methodologies.

The authors ( Cazavene, et al ) were trying to remove the el niño / la niña variations. Whether that is a good idea or not is a separate question. It seems they were successful in removing the “inter-annual” variations. Whether they have accurately described the steric and hydrological components in sea level rise is dubious. By adjusting parameters, no doubt any desired result could be obtained. Why should we be surprised they got their desired outcome ?

Keep watching Nature Climate Change for more !. Indeed, Nature calls.

Observa responds :

She lost me at hubris before we could get really hot and sweaty with complexity and chaos.  Another time perhaps ?

Valencia responds :

But it is not only that Cazenave 2014 is poorly thought out; it was meant to mislead, in my opinion this is even worse.

Ossqss asks :

I have often wondered what a persistent high pressure system does to sea levels when over the water for an extended period of time.

Willis Eschenbach responds :

Your intuition is good. In some cases, when studying sea levels researchers use an “inverse barometer” correction to account for exactly that effect, where high pressure pushes down on the ocean surface.

Here’s a back-of-the-envelope estimate. Total weight of the atmosphere is about 10 metres of water or so. Normal range of barometric pressure is about 980 to 1050 mbar (hPa), or about a ± 3.5% swing. Typical pressure moves are more on the order of ±1%, and 1% of 10 metres is 10 cm, or about 4″. So yes, pressure variations definitely move the surface of the ocean up and down, a 1% change in pressure is equivalent to a change in weight of 4″ of water.

 

Gyre-scale atmospheric pressure variations and their relation to 19th and 20th century sea level rise

 

 

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