Guest post by Steven Goddard
One of the most cited “proofs” of global warming is that sea level is rising, as can be seen in the graph below.
http://sealevel.colorado.edu/current/sl_noib_global_sm.jpg
This is a nonsensical argument, because sea level would be rising even if temperatures were going down, as they have been since 2002. The main reason why sea level rises is because the equilibrium between glacial ice and temperature is out of balance, and has been for the last 20,000 years.
http://www.globalwarmingart.com/wiki/Image:Post-Glacial_Sea_Level_png
Note that from 15,000 years ago to 8,000 years ago, sea level rose about 14mm/year – which is more than four times faster than the current rise rate of 3.3mm/year, as reported by the University of Colorado. During the last ice age, sea level was so low that people were able to walk from Siberia to Alaska across the Bering Strait. One of the more stunning pieces of evidence of this is the remarkable similarity of appearance and culture between the indigenous peoples of Eastern Siberia and North America.
In 2002, the BBC reported that a submerged city was found off the coast of India, 36 meters below sea level. This was long before the Hummer or coal fired power plant was invented. It is quite likely that low lying coastal areas will continue to get submerged, just as they have been for the last 20,000 years. During the last ice age, thick glaciers covered all of Canada and several states in the US, as well as all of Northern Europe. As that ice melts, the water flows into the ocean and raises sea level.
http://uk.encarta.msn.com/media_461527006/ice_extent_during_the_last_ice_age.html
The IPCC has stated that sea level may rise two meters this century, which would be a rate of 22mm/year, nearly seven times faster than current rates. Do we see such an acceleration? The simple answer is no. There has been very little change in sea level rise rates over the last 100 years, certainly nothing close to the immediate 7X acceleration which would be required to hit 2 meters.
Sea level is rising, and the abuse of this information is one of the most flagrantly clueless mantras of the alarmist community.
Even if we returned to a green utopian age, sea level would continue to rise at about the same rate – just as has done since the last glacial maximum.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Even a blind blond can see that first chart works better as a CURVE, closer in shape to the second chart, than as a straight line.
However, it’s more in line with the concensus to use that straight, scarey line.
What? The sea level is rising no faster that Solar Cycle 24?
Indeed, I can go visit my favorite places on the seashore, and I cannot tell you that even a half of a foot has gone under over the span of 50 years.
Eight inches rise since 1880.
Imagine that.
In my lifetime the sea has risen 3-1/8″. Wow.
Los Angeles’ Basin’s graben must be going down faster than that.
Catastrophic.
Unbeleiveable.
Oh dear, the top graph looks like the sea is dropping.
Hey, now is the time to invest in that hot beachfront property that extends out to sea that’s cheap because the water is too close.
Your neigbors to landward will be kicking themselves.
Other sealevel references at this post.
http://solarcycle24com.proboards106.com/index.cgi?board=globalwarming&action=display&thread=459
is there any more comprehensive data around than the 23 tide gauge records selected by the ipcc ?
is the satelitte raw data still flat and the slope still “corrected” from the tide gauge records (without annotating this in the grapics) ?
I am not sure that the sea levels are all that constant. According to The Indian National Institute of Oceanography the tidal gauge at Mombai, which has been recording water levels since 1875, does not show that trend.
Sea-level variability at Mumbai, which has the only more-than-century-long sea-level record in the Indian Ocean. Annual sea level (cm) is plotted as a function of time to reveal the variability of the annual sea level over the length of the data record (1878 to 1988 in this figure) (red), showing the inter-annual variability in sea level at Mumbai. Filtering annual sea level with a 10-year boxcar filter (10-year running mean) (blue) reveals inter-decadal variations. At Mumbai, these inter-decadal variations are as large as are the variations from year to year.
(If the image doesn’t come through I write about it here .
In the Bristol Channel between England and Wales, sea level varies by nearly 50 feet between high and low tide. Incoming high tides make a wave that people surf on. People there are smart enough not to build their homes on the mud flats.
I wonder if it is worth spending trillions of dollars in a vain attempt to save a few villages on Pacific Islands?
Does anyone else remember the Gilligan’s Island episode where the Professor determines that the island is sinking… and SO rapidly that they had only days to prepare. At the end of the episode it turned out that Gilligan had been moving the stick that the Professor was using as a sea-level indicator.
Somehow, every time I hear these Global Warming / Climate Change / Sinking Island / Rising Seawater stories, I flash back to that episode of Gilligan’s Island… and this is how I keep it all in perspective.
In 2002, the BBC reported that a submerged city was found off the coast of India, 36 meters below sea level.
That city would be more than 8 thousand years old if your graph 2 is correct Steven!
The BBC Time Team also reported on bronze age settlements on the floor of the North Sea off Dogger Bank from a similar period, so the indian city isn’t an isolated instance which could be written off as a ‘local’ phenomenon due to subduction either.
The level of historical ignorance in the alarmist community beggars belief. They look at 100 years of sea level change and extrapolate doom on the basis of a spurious co2 correlation. Talk about cherry picking data!
I have been doing a lot of reading on sea level rise and while I think IPCC’s temperature predictions are an exaggeration, they may be underpredicting sea level rise. They’re 2007 report states the best confidence interval at 8-17 inches and wider interval at 7-24″. From everything I am reading, a better estimate would be 10-35″ by 2100. There is a lot of uncertainty in the field of glaciology and it is very possible that melt will accelerate. Modeling indicates Greenland and west antarctica will accelerate melting. Don’t get me wrong, I agree 2m is not possible and I think 1.8C-4.0C is highly unlikely (from everything I’ve read on here and elsewhere I believe .5-1.5C to be the correct range for 2100). But I do think it is likely melting rates will accelerate beyond the 3mm of SLR/year we have seen so far. Read up on some scientific articles (but as always avoid anything by Hansen).
If sea level were to rise 2 meters (6 feet) in this century, the level would then be the same as it was 5000 years ago during the Climatic Optimum when fauna inhabiting the present Sahara Desert included hippos and cattle.
This does not deny a human role in modern global warming, but does imply that natural warming has occurred in the past on the same scale as projected by the models used to support IPCC recommendations.
If the causes of recent sea level rise are natural, then it is likely that money would be better spent in mitigating the effects of sea level rise than in trying to stop the inevitable. Phasing of mitigation efforts over a long period would also reduce the net present value of the costs and thus their adverse economic impacts.
References:
The Hanabuth Curve, Hanebuth T, et al. (2000). Rapid flooding of the Sunda Shelf – a late-glacial sea-level record. Science, 288: 1033-1035.
URL: http://www.geoscience-environment.com/es551/back_ground.html#quaternary
Topographic evidence for Quaternary sea-level change
Ara Valley, Penang Island, Malaysia , URL: http://www.geoscience-environment.com/ge703/index_sungai_ara.html
Steven Goddard (22:31:05) :
We’ve spent trillions of dollars in a vain attempt to save a few banks.
What difference does it make?
Today Obama announced the saving of 25 jobs in Columbus, Ohio. As we have spent some three trillion dollars on various bailouts, that works out to about $120 billion per job. See http://www.nytimes.com/2009/03/07/us/politics/07obama.html.
I’m tempering my enthusiasm for this heartwarming and cheering information with the following observation made in the article:
Or, you could just look at the $787 billion on the latest bailout signed here in Denver. Then, each job in Columbus, Ohio cost us only $31.48 billion per job.
Similar calculations need to be run on the carbon-free, alternative energy jobs about to be generated with a carbon cap and trade program being proposed now.
Cheers to all.
The pre-historic civilisations in India are now quite well-known, the Harrapan dates back to c 3300BC, the discoveries in the Gulf of Cambay are contentious, relying on sonar scans and a few pieces of wood dated to c 7500BC
http://en.wikipedia.org/wiki/Ruins_in_the_Gulf_of_Cambay
(OK, it’s Wiki, so not the most reliable of sources!)
Items of terrestrial origin are regularly dredged up from the North Sea, worked flints, Mammoth bones etc. http://news.bbc.co.uk/1/hi/sci/tech/7735544.stm
Steven Goddard (22:31:05) :
Remember that all those threatened Pacific islands have a maximum elevation of about four metres or so because they are made of coral. (The volcanic ones can be several thousand metres high but even the pinkogreenpeaceecofreaks haven’t quite got the nerve to claim that they are threatened). As far as I’m aware there are neither coral islands a couple of hundred feet high nor very many shoals a couple of hundred metres deep (yes, there are some flat-topped seamounts, but surprisingly few). We therefore have to postulate a huge population of flat-topped islands during the last glaciation with a uniform height of about 120m, and virtually nothing 100m or 150m high. Doesn’t sound very likely, does it?
Perhaps a more realistic view might be that coral islands can happily keep up with rises of sea level at rates of metres per century but will never manage to grow more than a couple of metres above the ambient sea level for fairly obvious reasons.
Remember King Canute! (or Knut if you prefer)
Steven,
Further to your reference to a suberged Indian city, and the above posts referring to Dogger Bank and fossils dredged from the North Sea.
I have always accepted reports that the English Channel covers large salt flats, ancient forests and entire river systems at about 20m depth. these included reports that the UK was recently connected to the mainland European continent. This was given as explanation for wolves, bears and wild pigs (now hunted to extinction) on this island, now separated from the mainland continent by about 20 miles of open water.
Nice short video here by Wessex Archaeology here:
Infio: “Archaeologists have created a 3D visualisation of a whole prehistoric landscape now submerged 20 metres under the English Channel, and 8 miles off the West Sussex coast. This is how we believe it may have looked over 8000 years ago, based upon environmental and geophysical surveys; an estuary populated by families living from the river, sea and land; a river surrounded by salt marsh and forest.”
More on the video author:
http://www.wessexarch.co.uk/about
You can get more up-to-date sea level data to the end of 2008 from Aviso (which has been operating the Jason-1 and Jason-2 satellites during the calibration period).
Sea level at the end of 2005 is still the highest.
http://www.aviso.oceanobs.com/fileadmin/images/news/indic/msl/MSL_Serie_J1_Global_NoIB_RWT_PGR_NoAdjust.png
There are quite different results however when one uses the different algorithms to remove the seasonal signal and for the inverse barometer correction.
Does anyone have links to parts 1 and 2? — John M Reynolds
Jordan (02:37:28) :
Steven,
Further to your reference to a suberged Indian city, and the above posts referring to Dogger Bank and fossils dredged from the North Sea…
There was also a program the BBC did about an island (one of the Scilly Isles off Cornwall) where there are many bronze age burials, but little room for farming. A hill connected by an isthmus to the mainland makes more sense as a burial site.
Fred Colbourne,
The reason why sea level rose quickly 5,000 years ago, was because there was a lot of ice to melt at lower latitudes and altitudes. Almost all of the remaining ice is at locations where the temperature never gets above freezing. The average altitude of the ice surface in Greenland and Antarctica is close to 10,000 feet. Little ice is going to melt at those high latitudes and altitudes, and in fact is accumulating rather than declining.
There are also underwater ruins off the coast of Yonaguni, an Okinawan Island just east of Taiwan, submerged in up to 25 meters of water. There is still controversy as to whether they are natural or manmade (judging from the photos and being a geologist, I tend to go with the manmade theory). The ruins are estimated to be around 5,000 years old. Another question not answered yet is whether these so-called ruins are the result of tectonic activity or were originally at that depth and rising ocean levels covered them. There are also ruins discovered off the coast of the main island of Okinawa at approximately the same depth which suggests to me that they were covered by sea level rise. The jury is still out on this one.
Another important point for why sea level rises during interglacial periods is glacial rebound. Basically, the weight of the ice depresses the earth’s crust during continental glaciations. Because the crust is rigid, that downward flex also depresses the adjacent ocean basins. Once the ice melts, the crust “rebounds back”- like a spring – thus decreasing ocean basin volumes along the edge of the basins & driving a small, long period increase in sea level. Thats a significant factor in why sea level is still rising even though the ice has long since melted. On the second plot of the post, you can see the long slow rising tail from 8000 years to present – that’s from the rebound effect. This tail is not well correlated with the temperature history, so this is not , in general, thermal expansion (although there would be a thermal expansion / contraction component of a shorter periodicity layered on.
See wiki on the subject – it is a pretty reasonable summary :
http://en.wikipedia.org/wiki/Post-glacial_rebound
To their credit (and maybe because few outside the geologic world have knowledge of the subject) , in the Global Warming section of this wiki entry, they actually recognize the significance of separating out the rebound signal & call it the most significant factor:
“Thus, to understand global warming from sea level change, one must be able to separate all these factors, especially postglacial rebound, since it is one of the leading factors.”
I am reticent to even post this as it may draw attention to it from some AGW self appointed wiki-editor who will change the entry, but these are the geologic facts – establish before any science associated with GW was corrupted by political agendas. Let’s watch & see if it does get edited. That will say a lot about the AGW crowd (although it certainly wouldn’t be surprising).
As I have said before, there is far too little geological input into the debate. Outside of climatologist, geologists have some of the most important data & perspective to offer on the debate.
Steven,
The background sea-level rise can be extracted from http://www.globalwarmingart.com/images/1/1e/Holocene_Sea_Level.png. The fit on this plot is shown as currently flat, but there is considerable scatter in the data. At a stretch the rate over the last six thousand years might be at most a rise of 1m/millennium. Hence the satellite-derived current rate of 3.3+/-0.4 m a year is at least three times the background level, and probably many more times larger.
Your basic geology seems to be letting you down here.
Jeff L,
Not sure I buy the glacial rebound theory wrt average global sea level. When the crust depresses into the mantle due to the weight of overlying glacial ice, it has to rise somewhere else. Remember that the weight of the oceans have the same effect of depressing the sea floor. The total amount of sea water decreases during ice ages, causing the sea floor to rise. Averaged out over the earth, it should be a wash.
Tom P,
The scarcity of data and standard deviation of the Holocene sea level graph you linked are much too large to make any meaningful conclusions about the “background .” This one is much better.
http://www.globalwarmingart.com/images/thumb/0/0f/Recent_Sea_Level_Rise.png/700px-Recent_Sea_Level_Rise.png