Friday
Sep042015
by 
Bishop Hill
Bishop Hill Gauges versus satellites
Sep 4, 2015 Climate: Oceans Climate: WG2 ;)
There is a fascinating post at No Tricks Zone on sea level rise, focusing particularly in the difference between the (heavily adjusted, short-term) satellite record and the (relatively pristine, long-term) tide-gauge data. The former is over 3mm per year, while the latter is much lower.
Author Dave Burton has been trying to reconcile the two numbers and has drawn a blank:
It is not possible to torture the tide-gauge data into yielding a globally averaged rate of relative sea-level rise anywhere near 3.3 mm/yr.
The upshot is that the satellite record might be as much as double the correct figure, or at least the relevant figure for coastal planning purposes. I wonder what figure is used for assessing the economic impacts of climate change?
Reader Comments (38)
In climate science, using computers to adjust figures upwards is normal procedure.
If I hacked a bank and adjusted my bank account in a similar manner, it would be fraud.
Bankers who manipulate figures used to be rewarded with bonuses, now Her Majesty rewards them with free board and lodging (seaviews not guaranteed)
Sometimes the warmsts make it too easy for sceptics to prove that their bandwagon is hopelessly corrupt but satellite vs land measurement is one of them. In both measurement of sea level and global temperature, the warmists choose the most alarmist as their poster children. Quelle surprise!
Of course they have to keep the sea level rise up because that's tied (or tide) up with all that missing warming going into the ocean.
Economic impact estimates are based on modelled, rather than measured, sea level rise. The models are calibrated to the tide-gauges.
This is a long running saga and John Daly dealt with it years ago. David Whitehouse also noted how much sea level rise advanced once satellites started the measuring.
http://www.john-daly.com/deadisle/
http://www.john-daly.com/altimetry/topex.htm#sthash.bB3W4ToG.dpuf
http://www.thegwpf.com/the-sea-level-acceleration-trap/
I keep wittering about it here - but the UK Environment Agency's TE2100 Thames Estuary project splurge rests on some wonky predictions that they will *not *expose the workings of - whilst simultaneously spaffing billions of OPM pounds on sea defenses sized according to scary and unsubstantiated predictions....
The satellite sea level record really deserves a good going over - I actually wonder if the raw data is actually available without adjustments.
Look out for OCO2 data to be tortured in similar fashion - still VERY, VERY quiet on that front eh? Over 1 year on task scanning away and zip, nada in the public domain - we know more about Pluto?
I would caution against calling the tide-gauges "pristine". The land is moving, of course; gauges have been moved too; equipment replaced; and you can even see industrial action in the records (the Thatcher years being notorious in this regard).
Richard Tol
after 35+ years meddling with tide gauges - "pristine" isn't a word I usually associate with that instrument :-)
I agree with Richard Tol's post, in that the Integrated Assessment Models usually have a module to project sea level rise based upon emissions in the future. What they are calibrated to depends upon the user of the model and the scientific information they find persuasive.
In the default PAGE09 model, the projected sea level rise ranges are quite wide reflecting the continuing uncertainty. The default model has a 90%CI of 43 - 115 cm sea level rise in 2100 from RCP8.5 emissions, for example.
@cwhope
Its worth the visit just to read Dave Burton's quietly corruscating put down of a troll named Sod (!), with a succinct explanation of why satellites don't work for sea level but do for temperature and why tide gauges are measuring a global constant but thermometers are not.
Chris Hope:
How seriously do the alarmists take their projections? I note that Tim Flannery (6 metres by 2100), Al Gore, Kevin Rudd (the great moral problem of our time), Julia Gillard have all moved to residences by the sea shore. Readers may be able to add others, this being mostly Australian Prophets of Doom.
Richard Tol, yes agreed about tide guages, but coastal erosion is described as being due to climate change, and natural compaction and compression of soils and strata is described as being due to climate change etc etc.
In the UK, a trip to historic ports and docks generally reveals no evidence of raised defences against rising seas. Some sea defences have been raised to reduce the financial cost of occasional storms, now that buildings, land and property is more expensive to restore after flooding, not because flooding is more severe or regular.
The same applies to "Riverside Cottages", which would flood on a regular basis. Historically, people would open the doors, and wait for the water to flow out again. Nowadays expectations are higher, and people have insurance, electricity, mains drains, plastered walls etc., cars. 100 years ago, a flooded property would cost nothing to restore to habitable condition, apart from hard work and cleaning. The same property today, will cost 10's of thousands
@diogenese2,
The questions from sod are actually perfectly sensible, and dismissing him as a troll seems unfair. The replies from Dave Burton look OK, although he is ignoring local gravitational effects which I understand can be significant (it doesn't matter where you add water, but it does matter where you remove ice).
Actually it's worse than you suggest because the argument usually presented by alarmist scientivists is that the sea level rise is accelerating. When you explore this claim you realise it is entirely based on the jump to satellite-based 3.3mm from the tide-gauge-based 1.7mm. They do exactly the same with the ocean heat measurements based on the (you'd think obvious) unresolved artificial jump between Argo and XBT measurements (eg Levitus). You wouldn't think scientists could be so obtuse but when they want to force a political outcome then no trick is too underhand and splicing of incompatible data seems to be one of the standard modus operandi in climate circles along with biased data-mining, end-point pinning, rejecting data that disagree, unphysical & circular argumentation, assuming that nature is dormant, rejecting model validation and much more that used to be called plain bad science.
How many British MPs know that there is a significant discrepancy between the tide-gauge data and the satellite data for sea level rise? In fact, is there any country in which many politicians are aware of the discrepancy and would they care even if they did know about it?
Richard Tol, the issue is not that the tide guages are pristine but that all of it is iffy. Climate science is happy to tack moden satellite measurements onto old, earth based records, where it suits them. They like to pretend they have a long, credible history. If they just presented the 'accurate' modern measurements they would have almost nothing to show.
Or they might ignore the satellite measurements if that tells the wrong story. At that point they argue that the satellite is missing some of the details that the Earth based system picks up. How bloody convenient.
Those tide gauges are rising, I tell ya!
Tiny
You remind me of an attempt some years ago to disprove the inconvenient greening of the planet by re-colouring some of the green satellite output to be brown. Like the supposed Antarctic warming it was just too far out to become mainstream but there is no limit to the adjustment chicanery of confirmed believers. After all NOAA rejected accurate Argo data and the satellite measurements in favour of bucket measurements in order to produce a result consistent with CO2 being the main driver of temps and it was universally reported as if it was a real scientific discovery.
I am constantly amused at the relationship the warmists have with new technology.
For instance, they insist that the satellite temperature readings are wrong and that the adjusted thermometer readings are correct, yet they also insist that the tide gauges are useless but the adjusted satellite sea levels are the bee's knees.
Then again, NOAA have, at great expense, installed a large number of new climate stations in the continental US, but unfortunately they show a falling temperature trend so clearly can't be used to sanity check the adjustments on the old thermometers.
The old method of finding sea surface temperatures by adjusting the water intake readings from ships to fit the paradigm wasn't very satisfactory so they launched a large, (and increasing), number of expensive buoys to accurately measure SST, but unfortunately, the shiny new toys failed to show the correct increase in SST until they were adjusted to match the old engine intakes.
It's a puzzle why all the super sophisticated technology so frequently give the wrong result. New tech is obviously crap so why do they keep installing it?
Roy, the Government employs experts, to tell the Government what it needs to hear, not what it does not want to hear.
Unfortunately, as Yes Prime Minister demonstrated, it tends to be self important civil servants, who control what the Government hears, and therefore does not hear. This helps reinforce a Governments opinion that they are responding to what the public wants, when in reality they are only responding to what civil servants have already decided.
The modern example of this is President Obama and his top advisor on Climate Change, John Holdren.
Sea levels is slowly rising upwards OR the land mass is slowly tipping downwards.
Orbiting Satellites cant monitor undersea /ocean floor continental drift.
Like having a plastic Paddling pool in your garden with a constant level of water until your dog crawls underneath it during an Earth quake on a vibrating bed.
Only way to accurately measure the volume of water and ice in the oceans is take a fixed datum point in space the center of the sun relative to the Earth Orbit and measure the depth to each point on the Earths surface.
Related is the following.
It seem that SLR measurements have something in common with temperature measurements:
1) The uncertainties in physical measurements are relatively large compared to the changes being measured or postulated to be occuring.
2) Advocates of disaster still rely on disaster happening at some point in the modeled future, when it is not clear that anything unusual is actually happening now.
Nils-Axel-Morner is a very experienced oceanographer who is extremely (rabidly?) critical of conventional estimates of SLR. He may be the best source for skeptics. See his report linked below and (for balance) a reply at SKS
http://scienceandpublicpolicy.org/images/stories/papers/reprint/sea_level_not_rising.pdf
http://skepticalscience.com/Nils-Axel-Morner-wrong-about-sea-level-rise.html
1) Figure 4 claims to show how the IPCC cherry-picked tide gauge records - which give a wide range of values due to glacial isostatic rebound, settling, and other issues specific to individual tide gauge sites.
2) He shows photographic evidence that whatever SLR is occurring globally, it hasn't yet caused detectable change in the Maldives or other infamous low islands.
3) Most disturbingly, he claims the satellite record has been adjusted to match SLR at a very few selected tide gauges and is not an independent way of measuring SLR.
FWIW, I personally find claim 3) hard to believe and the first two somewhat plausible.
So the satellite data shows a greater rise in sea level than the tidal gauges? Elsewhere, I have seen some rather interesting sites talking about an expanding world. I have always wondered, when I read about a major earthquake causing a shift - Japan moved 8 inches from the Fukishima earthquake, or something like that. Problem I always had with statements like that was relative to what? Did it move towards Asia and away from North America? Towards the north pole and away from the south pole? Or was it just away from North America but not towards Asia?
So if the Earth was expanding by some small amount each year, then the surface would be rising erroneously relative to the satellites. Perhaps it isn't "glacial rebound" and "rising sea levels" at all, just Mother Earth gaining a little girth. Surely there must be a "proxy" we can use to determine whether that is true or not.
I also keep an eye on sea levels from time to time using data from psmsl.org which offers free access to historical tide gauge data from around the world.
The Nasa press release quoted colorado university sea level group for their claims which have to involve an acceleration to 3x times current rate of sea level rise. Yet the front page of the Colorado sea level group shows absolutely no sign of long term acceleration at all.
Just by clicking on a tab on this web page anyone can see a table of results of tide gauge studies almost all in the 1-2mm/year range.
It is obvious tide gauges, which measure sea levels by land, and satellites, which attempt to measure across the whole ocean, are measuring different things.
Moreover, as Steven Goddard has pointed out, the error in the satellite measurements are about equal to the claimed rate of sea level rise - in other words the actual rate could be zero.
On the other hand the Mount Pinatubo volcano eruption in 1991 depressed sea levels around the world, after a few levels sea levels recovered leading to a greater than normal rate of sea level rise, and just after this there was the exceptional 1998 El Nino which raised sea levels around the world. The combination of these two events lead to several years of above normal rates of SLR.
More gory details here Nasa makes false claims about sea level rise
It is silly to plot straight lines on graphs of sea levels when it is known there is a cycle of around 60 years in sea levels.
It is also silly to plot straight lines when it is known sea levels don't rise linearly, this is in addition to the cycles, occasionally levels change abruptly - because of earthquakes for example. Nils Axel-Morner talked about this at a Heartland conference a few years ago.
@Frank I don't see why you find it hard to believe satellite results have been altered. Have a look at Steven Goddard's graph of recent GISS adjustments which curiously seem to follow the increase in co2!
This is an issue that affects me directly. I am a resident of Christchurch NZ where the council have a proposed district plan that uses the assumption of 0.4m SLR by 2050 and 1m by 2100
This is going to provide very severe restrictions on building in the modelled areas, and affects around 18,000 property owners, with potential issues around insurance and getting mortgages. This affects me because my property falls within the modelled inundation zone. We took a cash settlement after the insurance wrote our property off after the Feb 2011 earthquake. The house is still habitable but we need to decide on whether we can repair or rebuild on the site
The one metre assumption is based on the upper bound of RCP8.5
This is something that has been discussed here, of course, as being somewhat pessimistic.
However, I note that the RCP website portal has a disclaimer that RCPs are not forecasts, nor are they designed for public policy
I would be interested to hear some feedback on this from the climate community.
I am not from the climate science community, and would offer the following suggestions based on some practical experience
Obtain some tide tables from 10-100 years ago. Library? Internet? Look at maximum heights predicted, and compare them with tide tables and heights today.
Visit some of those coastal areas, and see whether any coastal defences have been raised, improved, or repaired, and speak to local people, checking any significant stories with press records.
Plot any information about a rise in sealevel relative to land level, and work out any change over as long a timescale as you can.
Compare YOUR information, gathered from YOUR observations and YOUR research, with the OFFICIAL records and FORECASTS made on the assumption that sea level WILL rise.
You will now have a more accurate information database, than climate experts, who use computers to measure sea level. In the modern age, assume that computer aided sea level measurement would be more reliable, if you tied a piece of string around an old computer, and used it to plumb the depth by hand. (Any pieces of chewing gum stuck to the computer, will allow you to assess the nature of the sea bed)
Decide for yourself whether you prefer the experts advice, or your own observations
golf charlie -
I already have the tide gauge data for Lyttelton which shows a fairly linear trend of 17cm / Century
This is also in the peer-reviewed literature (Hannah and Bell 2012)
A friend also submitted an FOI request for the info (bit of overkill) which also stated 17cm/century from the government office
However, the local council assume the worst case of RCP 8.5 projections and use that rather than the observational data.
There is quite a lot going on here. Christchurch has suffered devastating earthquakes and the damage to infrastructure and associated insurance costs are huge.
Many of us are feeling that "climate change" is being as a hammer to excuse the insurance industry from meeting their obligations.
There is a local residents group which has grown rapidly in the last two weeks. There have been several TV interviews and a local Maori elder statesman and businessman, Sir Tipene O'Regan, is batting for our side
This has the potential to escalate to national government level, and could develop into quite a big climate change story downunder.
It is true that Christchurch has very serious infrastructure issues, but I don't like them being dealt with under some rather arbitrary climate assumptions.
A TV interview with Sir Tipene is here
Some background here
Andy Scrase, thanks for that. Interesting reading!
I am not an expert, and have no knowledge of your area, but
17cm per century from 2 different sources, probably means they both use the same data/tide guage. Check back as far as you can, preferably using old paper data, NOT modern computerised, to make sure you do not get unfavourably homogenised.
Earthquakes do change sea level relative to land level. Can you plot any change due to sudden and/or gradual progressive sea level vs land level, as opposed to sea getting more full.
I have some knowledge of insurance in the UK, but none about NZ or earthquakes. You mention major infrastructure issues. I have to make some educated guesses/assumptions ......
IF your property is damaged, and insured, your insurance co should fix the damage, but can not make your house earthquake proof. Your Ins co can not pay to repair roads drains utilities in the neighbourhood.
Your local council and utility providers may have no insurance to cover repairs, let alone improvements.
If you and fellow householders all have finance (insurance) to repair the houses, it may be that it will cost your council/utlities millions to repair the services, with no guarantee that they will not have to repair it all over again in 10 years time.
Therefore it might be in the interest of your council and utilities to abandon the affected area, and get insurance cos to compensate the homeowners. It would be logical for the council to agree with the worst case sea level rise prediction.
I would suggest you carry on making your own assessment of sea level rise, noting very carefully your sources, and how independent they are of vested interests. You can do most of the historical and actual record checks.
You and colleagues do need a good lawyer. You need to be able to establish if your council has decided to put its financial liabilities, both present and future, before the best interests of the community. It may be they had no other choice. Obviously if such a decision was based on suspect information .....
The issue is beyond checking facts. The city council voted in the One Metre SLR by 2100 policy on no scientific evidence whatsoever, and now about 18,000 properties are affected, devaluing their worth, and making insurance and loans difficult if not impossible
It is hard to imagine a more bone-headed climate change policy
We may disagree on things like carbon taxes, renewable subsidies, etc, but forcing people into a "managed retreat" (their words) from the coast based on a modelled projection seems complete lunacy to me, as do the 850 people who have joined the CCRU facebook group in the last 2 weeks, and the 500 people who have turned up at our recent public meetings.
@Andy Scrase
I think you have done the right thing, the solution is political not through trying to convince elected officials of science, they will simply defer to likes of IPCC.
I live about 1/2 mile from sea wall in Essex, UK. When Environment Agency wanted to knock down part of sea wall and flood farm land because of threat of rising sea levels, EA were sent loads of graphs and tables and papers about sea levels which left them completely unmoved. They just said we have to work to DEFRA (government) projections. The local council just did whatever EA said. They had to EA provided the money, and DEFRA provided EA's money.
Even if you did start to get through to them the council would probably start waffling on about worst case scenarios and precautionary principle.
In 2006 DEFRA was predicted around 1m sea level rise by 2100, in 2009 they came out with lower predictions in 3 flavours (high medium low). Here (hopefully) is a graph with
Observations of sea level from Felixstowe
Trend Line
2006 DEFRA prediction
3x 2009 DEFRA predictions
sea levels at Felixstowe
Whilst the graphs and facts may not help with your council they will help explain to fellow residents of the stupidity of the councils actions.
The key point to stress is to get 1metre of sea level rise, the rate of sea level rise has to accelerate to about 10mm/year, 3 times what the satellites currently measure, maybe more than 5 times what tide gauges measure.
There is absolutely no sign of this happening at all long term (ie more than a decade) .
What changed things for us was angry people packing out meetings with Environment Agency
and hundreds of people going on a protest march along the sea wall which EA wanted to knock a hole in.
The one thing which stirs politicians to action is the threat of losing their seat.
I must apologise as it seems this stuff about managed retreat has spread out from UK (and Essex in particular) like some malign virus. Though the name has changed to managed realignment as 'retreat' sounded a bit negative.
Andy Scrase and Jeremy Shiers,
"Managed Retreat", is a euphemism for spending the least amount of money, and justifying it by blaming the unstoppable global warming induced sea level rise.
When you do the sums, it makes sense, but not when you question the assumptions made to produce the figures, to do the sums, yourself.
Examples around the UK are generally NOT due to land level dropping relative to sea level, but are coastal erosion. Around Essex, and up around East Anglia, much of the land was reclaimed from salt water marshes. The original work dates back 3-500 years, and was engineered by the dutch, who remain experts to this day. Ever noticed Dutch architecture in historic houses around East Anglia?
Managed retreat is cheap and simple. It is favoured by simple people, who find it easy to understand, and cheap. It is supported by the Governments expensive experts, who rely on dubious assumptions and dodgier data, to make decisions, which simple people understand, because they are cheap, and final.
Jeremy Shiers,
Anyone criticising "Managed Retreat" is portrayed as being negative. It is cheap and simple to alter public opnion, with PR spin. NGO's, environmental activists, and charities etc are great at PR spin. The media give them free advertising, and political broadcasts too!
Jeremy Shiers - sent an email to you via your website
Great blog you have by the way. Some very useful resources there
Andy: Evidence for any acceleration in the rate of SLR is tenuous given the observed variability in that rate. Right now, the rate is about 1 inch/decade and acceleration is indistinguishable from 0 inch/decade/decade. If that continues, that is 9 inches of SLR by 2100, about the same as the 20th century. Now suppose acceleration of SLR has actually begun and is 1 inch/decade/decade. That would easily be detected in less than a decade. That would give 14 inches by 2055 and 35 inches by 2095. Once we clearly can detect and acceleration in SLR from 1 to 2 inch/ decade, we need to worry that SLR is on target for rising about 1 m in the next century. Until then, expecting current trends to continue seems prudent enough. There will be decades of time to respond to acceleration in the rate of SLR once acceleration has been detected. The low end of the IPCC's range include very little acceleration!
In a sensible world without government interference in the marketplace, YOU and your insurance company would be responsible for the risk you are running from earthquakes, subsidence, and SLR. Your community takes on risks to to services like roads, sewers, power, etc. If your and their investment horizon reaches out a century in the future, waiting for acceleration in SLR to be clearly detected may be too risky. However, what lasts for a century without major repair along the way?
Frank, I agree with everything you say, but things are out of our hands and the "government is here to help us"
There is a general feeling that this is a stitch up between the insurers and the government. The local council are just the unfortunate suckers that have been told to implement the policy
We have some good people on our side and if we can escalate this to national government level, then the proverbial will really hit the fan. For example, much of the capital, Wellington, is on reclaimed seaside land (including many government offices)
For that reason they will try to push the onus onto local authorities.
We got 850 people join our "Canterbury Coastal Residents United" (CCRU) Facebook group in just two weeks (which people here are most welcome to join).
At our last public meeting, Sir Tipene O'Regan, Maori businessman and elder statesman of Ngai Tahu, stood up and eloquently described why global warming was "bureaucratic nonsense that seems to defy all logic and reason", which was greeted with a round of applause from the 250+ gathered.
I was quite overcome that I would ever see this in public.
Andy: your city is abusing the precautionary principle: pay any cost now to avoid POTENTIAL future environmental problems. The rational response is that scientist can easily detect the acceleration in SRrL needed to produce 1 m of SLR in a century about a century's before SLR reaches 1 m. With that much warning, there is little need to place restrictions on property owners today.
Bish: I am afraid the linke d post compares average SLR over the life time of each tide gauge (average 90 years) to SLR during the sa tellite altimeters era (20 years).