Sea Level Data In Monthly Format
Guest post by Bob Tisdale
In this post I have also provided comparisons to scaled NINO3.4 SST anomalies. As could be expected, some of the rises and falls are related to ENSO events. The step changes also appear to be direct responses to El Nino events. I am not, however, implying that Sea Level variability is only impacted by ENSO.GLOBAL SEA LEVEL
The monthly Global Sea Level data from December 1992 to March 2009 is illustrated in Figure 1. The late 1995 spike in the sea level data stands out similarly to the way the 1997/98 El Nino stands out in global temperature data.
http://i31.tinypic.com/op5nw1.png
Figure 1
Figure 2 compares Global Sea Level to scaled NINO3.4 SST anomalies. The peak in late 2005 is not directly related to an El Nino. The impacts of the 1997/98 and the 2002/03 El Nino events, however, can be seen in the Global Sea Level data.
http://i31.tinypic.com/2mrgo5x.png
Figure 2
MONTHLY SEA LEVEL FOR THE ATLANTIC, INDIAN, AND PACIFIC OCEANS
As preliminary notes, the annual variability in the Atlantic and Indian Ocean Sea Level data can be clearly seen in the monthly data. The Pacific data is noisier, which masks an annual signal.
Note how the smoothed Atlantic Sea Level data, Figure 3, appears to rise in steps. The first step is in 1995. This should be a rebound from the Mount Pinatubo aerosol effects.
http://i27.tinypic.com/zs4m0.png
Figure 3
The scaled NINO3.4 SST anomaly data has been added in Figure 4. The smoothed Atlantic Sea Level data rises again in 1997, which should be a response to the 1997/98 El Nino. Are the rises in 2003 and 2005 also responses to the 2003/04 and 2004/05 El Nino events?
http://i32.tinypic.com/t8nrch.png
Figure 4
The raw and smoothed Indian Ocean Sea Level data, Figure 5, show a major step change in 1998 and a curious increase in trend in 2004.
http://i31.tinypic.com/25qzrdi.png
Figure 5
The 1998 upward step in the smoothed Indian Ocean Sea Level data appears to be a lagged response to the 1997/98 El Nino. Refer to Figure 6. The 2004 change in trend does not appear to be ENSO related. Was there a shift in Indian Ocean cloud cover in 2004?
http://i31.tinypic.com/1415glt.png
Figure 6
Following the significant increase from 1998 to 2002, the Pacific Ocean Sea Level, Figure 7, has been relatively flat since 2002. The rise in Pacific Sea Level slowed after 2002, and Pacific Sea Level has declined since 2006.
http://i31.tinypic.com/hsta3q.png
Figure 7
In the comparison with NINO3.4 SST anomalies, Figure 8, note how the Pacific Ocean Sea Level surged upward in mid-1996, one year before the 1997/98 El Nino. Does this indicate that there was a sudden rise in ocean heat content in the year leading up to that El Nino? Does this confirm the findings in my post “Did A Decrease In Total Cloud Amount Fuel The 1997/98 El Nino?” It does seem to show that the 1997/98 El Nino was fueled by a short-term change (one year) in the ocean heat content of the Pacific.
http://i28.tinypic.com/2enn4lk.png
Figure 8
ATLANTIC, INDIAN, AND PACIFIC OCEAN COMPARISONS
Figure 9 is a comparison of Sea Levels for the Atlantic, Indian, and Pacific Oceans. Note how one dataset always appears to be out of phase with the variations of the other two. Rarely do the sea levels of all three oceans rise or fall in unison.
http://i30.tinypic.com/2wh2k9f.png
Figure 9
The SST anomalies for the Atlantic, Indian, and Pacific Oceans are illustrated in Figure 10. There are significant differences between the SST and Sea Level curves. (I can’t see any reason to compare the individual ocean sea level and SST data.)
http://i32.tinypic.com/2gxl5ja.png
Figure 10
SOURCE
Sea Level data is available through the University of Colorado at Boulder webpage:http://sealevel.colorado.edu/index.php
Specifically:http://sealevel.colorado.edu/results.php
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Steven Hill wrote: Has someone did a study on just the increase of CO2 due to population increases and exhaling of CO2? Maybe some Government will release the Swine Flu or something to reduce the population. Oh, did I say that? Ouch!
There is a study on the impact of human heat emissions here:
http://www.ltu.se/forskning/1.16009?l=en&pureId=2090518&pureFamily=dk.atira.pure.families.publication.shared.model.Publication
Essentially the conclusion is that heat of all sources emitted by humans account for around 75% of the recorded heating blamed on AGW, but not through CO2 emissions. These are only recorded as having caused around 25%.
Steven Hill:
You forgot to mention all the carbon-dioxide being released from fizzy drinks bottles like Coca-Cola. That’s what’s doing it! Coca-Cola is destroying the planet!
Don’t worry dear believers, you know that many of your prophets have beach houses, so you won’ t drown at least in the near future…believe them!
Bob, the ’98 el nino released a huge amount of heat from the oceans into the atmosphere, which can’t have had an instant effect on glaciers. How come the sea lvel jumped upwards and back down around 1998?
First thanks for the data and analysis —
How an engineer looks at sea level:
1. How low was the water level during the last ice age?
2. How high has it risen since the last ice age thawed out?
That would be about 100 meters or so rise since the end of the last ice age.
OK so what do we have going on now? Engineer’s answer: mm of change, hmmm — Margin of error.
By the chart of and depth’s in SW Florida, I am in deep water soon. Better pack the boat now just in case. I always liked this song by Johnny Cash http://www.youtube.com/watch?v=91OIaPRrDts
Just to answer my own question, solar cycle 23 was on the upramp which would have raised levels, and the release of heat dropped them again. They soon started upwards again as ss23 was still waxing.
PSU-EMS-Alum (10:37:28) :
That being said, did the seafloor uplift during the 2004-12 Indian Ocean earthquake have any measurable long term affect on sea level, local or otherwise?
I wondered the same myself.
Have the world’s Navys been contributing much data relating to the seas? Given the usefulness of thermoclines for submarine/antisubmarine warfare I’m assuming they may have amassed a pile of potentially useful historical data. Plus whether they’ve released ice thickness data from sub-polar work, or if that’s considered too sensitive.
All the fuss over a range of a few inches. That’s it.
Hurry, sell your beachfront property, you must act quickly. I can see the handwriting on the warming already. KilGore was here.
Now, why would they be deeping the Suez and Panama Canals? If sea levels are rising, who cares about the approaches.
If history is any guide, the rise is slow and the fall is abrupt.
Why is that? When the ice melts, the land rises up as the weight is lifted. Higher land where ice abounds gathers more. Held in check.
My best guess is that when the climate turns colder, the land massses fall under the weight far more grudgingly. The volcanoes might be the pressure relief valve that allow this. Geologic study needed.
timetochooseagain (09:21:02)>>
Oh, I’m not worried. I live on a hill. 😉
No, really, I’m not worried at all. I was just thinking that if sea levels are rising there certainly would be some amount of reporting about damaged stuff from around the world, but I hear nothing about this in media. I find that strange.
WRT plate tectonics, NZ had its largest earthquake for almost 80 years just a week ago, magnitude 7.8 and equal to the devastating 1931 quake that effectively devastated Napier.
No injuries, relatively little damage, but the southern South Island is now around a foot closer to Australia. The area around the epicentre is also about three feet higher. Haven’t noticed any sea level change, though. Nor any reduction in airfares.
Off topic: Seattle area readers may be interested in attending this global warming conference tomorrow. This was the first I had heard of the event, though I read several Washington state news sites everyday. Imagine that, the mainstream media ignoring skeptics!
http://www.washingtonpolicy.org/events/environment_2009.html
I won’t be holding my breath waiting for the Seattle Times to report on this event in Friday’s edition.
Not too strange that they can’t report such a tiny change doing damage, but that doesn’t stop them from trying, in my experience.
You’ve all forgotten the effect of new supertankers and container ships displacing hugh volumes of water, ergo the sea level rises. Remove all the ships from the sea and problem solved;-)
Lots of nice data Bob; not so easy to figure the whys and wherefores.
Everybody understands there is a simple thermal expansion component. Somewhere I remember reading that in fact mid ocean temperatures were inferred from satellite radar measurements of the sea surface level, and then computing back from the assumed expansion. I remember reading it, but haven’t a clue where, and maybe it’s an urban legend. And if expansion is only part of the equation, then that wouldn’t seem to be a sound methodology; certainly highly indirect; about as proxy as one could imagine.
But if one makes a simplifying assumption; that the coefficient of expansion is a constant, and doesn’t vary with temperature or salinity (fat chance); then one can make a good case for arguing that the sea level rise (due to expansion) simply depends on the total “heat” energy increment.
Assuming (and we know what assume means), constant coefficient of expansion, and constant specific heat, independent of T and S (salinity), then a given amount of “heat” energy can warm a long column of water by a small delta T, or a shorter column of water, by a larger delta T, and even the stick in the sand approach, will show exactly the same rise in height of that column for a fixed increment of thermal energy.
Now given that we are not talking about a huge delta temperature range, in the tropical regions; those assumptions of parameter constancy, are probably reasonable.
When you get to the polar seas, where the temperatures are zero C or sub zero, then the assumption of a constant temperature coefficient of expansion is a bit more frivolous, since salt water freezes at the point of maximum density around -2.5 deg c for 2.47% salinity, and typical ocean salinity is 3.5%, and may be considerably larger near growing ice, due to the salt exclusion from the ice.
But in any case, in those polar seas, if we actually do have global warming and ice loss, then the polar seas would actually be cooling from giving up the latent heat to melt the ice; so the polar sea level would be falling; and in the case of the Arctic Ocean, has in fact been measured to be falling (over ten years) by 2 mm per year (as of mid 2006).
But in tropical oceans, an assumption of a fixed sea level rise for a given heat energy addition; regardless of energy distribution; would be reasonable.
Looking at your graphs with the SSTs, my eye (I have simply awful eyesight), says if anything the SSTs have fallen slightly; so I don’t see a connection bewteen SSTs and sea level rise. If that is a totally wrong observation; I’d be happy to hear that. Of course I am not looking for any thermal delays either. Does it make sense to you, that since total sea level rise would seem to be independent of the actual thermal energy distributiuon with depth, the expansion would not be delayed (much). You dump a lot of “heat” into a thin surface layer, and it expands greatly, and promptly, by a certain amount. As the energy disperses to deeper waters (taking its time), you get a lesser temperature rise, of a greater column of water; but the total vertical expansion remains constant.
So i think it is a mistake to expect any significant delay of sea level rise due to just “heat” energy input.
Now for water mass increases, due to land runoff from whatever mechanisms; I would expect a time delay.
Does any of this make any sense to you Bob ??
George
Patrik (12:31:09) :
Outstanding, Patrick. You just hit the 4d finsish nail on the head heard round the world.
Sea level RISE is a gross exaggeration and misleading.
Sea level CREEP would be far more fitting a description.
Another contributor to raising sea level must be the estimated 800,000 ton “dustball” reported in the UK Daily Telegraph today. (http://www.telegraph.co.uk/news/worldnews/asia/china/5877583/Giant-Chinese-dustball-circles-the-Earth.html).
“A group of Chinese and Japanese scientists claimed that the dustball, which weighed 800,000 tons, was kicked up during a storm in 2007 in the Taklamakan desert.
The desert, which is roughly the size of France, lies in China’s far-Western Xinjiang province, and is fringed by mountains on three sides, including the Pamir mountains on the border with Afghanistan and the Karakoram range, an extension of the Himalayas.
The dust ball was formed when a wind storm ripped across the desert, kicking up the dust, and trapping it against the mountains of the Tibetan plateau.
The scientists said the dust was forced higher and higher into the air, until it reached an altitude of around 16,250ft. A warm convection flow then lofted it further to between 26,000 ft and 32,500 ft, well above cloud level.
The dust was then trapped in the polar jetstream, a fast-flowing air current that lies just under the stratosphere, and began its “journey around the world” according to the Nature Geoscience journal.
The team of scientists tracked the progress of the cloud using tools aboard the Nasa observation satellite Calypso. After 13 days, the plume of dust passed back over the Taklamakan desert, having completed a full circuit of the globe. The scientists noted that even after such a long journey, the dust remained “tightly confined in latitude”.
It only fell back down to earth after crossing half the globe again when the cloud encountered a ridge of low pressure and fell into the Pacific ocean. Some of the dust managed to reach North America and then fall into the Atlantic.
“The Taklamakan desert is a major source of dust transported and deposited around the globe,” the scientists noted, adding that dust from the desert has turned up in ice cores in Greenland and in the French Alps. They also suggested that micro-nutrients from the dust could have a beneficial effect on the oceans, helping to feed plankton. ”
OK – it’s probably not a particulary significant amount in terms of the total volume of the oceans, but it is the consequence of just one event. This does show that there must be a substantial amount of solids picked up from the land by weather events and deposited in the sea, over and above that carried into the sea by run-off….. and that’s without all the fat plankton boosting the volume
Bob,
To facilitate Nino phase-comparison’s, you might try:
A) differencing.
B) year-over-year differencing …which is equivalent to time-integrating (smoothing or summing) A at annual-bandwidth.
Also, don’t forget the long-term, stone-soup effect on the ocean from outer space detritus — a few tons a year isn’t much, but over the ages it adds an upward trend that we can’t directly measure in our short time span.
Choa et al in Science 11 apr 08 state that there is an essentially constant rise in sea levels of 2.46mm per year for the last 80 years once fresh water impoundment has been taken into account.
tallbloke: You wrote, “Bob, the ‘98 el nino released a huge amount of heat from the oceans into the atmosphere, which can’t have had an instant effect on glaciers. How come the sea lvel jumped upwards and back down around 1998?”
Global TLT rose as a result of the 1997/98 El Nino and so did Global SST, including areas outside of the tropical Pacific.
Allan M R MacRae: You wrote, “If you have time, please plot seasonal (monthly) sea level vs the seasonal CO2 sawtooth data, and let us know what you find.”
Please provide a link to the specific CO2 dataset you’d like compared.
First July in Ky history that won’t have one single day in the 90’s. 67 right now with rain. 3rd straight day without AC for us.
Major Atlantic spikes lag major Pacific spikes by (on the order of) ~1 year. This is a new set of time-series for me — is this a well-know phase-lag that has been well-explained?
noaaprogrammer (14:14:43) : Also, don’t forget the water-bearing comets that add to our H2O inventory …
http://csep10.phys.utk.edu/astr161/lect/comets/smallcomets.html