Bishop Hill Euan Mearns on the Met Office report
Feb 24, 2014 Climate: MetOffice Climate: WG2 Euan Mearns has been analysing the Met Office's report on the floods and has raised some important concerns:
Sea level along the English Channel has already risen by about 12cm in the last 100 years. With the warming we are already committed to over the next few decades, a further 11-16cm of sea level rise is likely by 2030. This equates to 23-27cm (9-101⁄2 inches) of total sea level rise since 1900.
12 cm in 100 years translates to 1.2 mm per year of sea level rise along the English channel over the past 100 years. The Met Office is now suggesting that this is going to accelerate to 13.5 cm (median) in the next 16 years giving a rate of 8.4 mm per year until 2030. This represents an acceleration in the rate of sea level rise of 700% that is forecast to start happening tomorrow! This must surely be total drivel (Figure 3).
There is also this worry about the report's coverage of tides:
In the main body of the report the authors do discuss the exceptional Spring tides of early and late January but in the summary instead choose to present drivel on sea levels. Clive Best has estimated that the additional tidal height caused by rare alignments of Earth, Moon and Sun may have added over a meter to the normal Spring tide events. If correct this will have added significantly to coastal flooding and is totally unconnected to manmade global warming.
As Euan explains, the report is not all bad, but some of the issues he raises, and the fact that some high, but not exceptional rainfall caused a report to be published in the first place, make it look as if there is a political subtext to its publication.
Reader Comments (59)
Ruth, as far as I understand it sea level referred to the geocentric mean is referenced to the centre of Earth and such sea levels are determined by satellite altimetry. I don't know quite how one relates this to local sea level changes as recorded by for example tide gauges and will have to study Wahl in detail to see how they do it. One could take the relative mean sea level as recorded by a tide gauge and subtract the vertical displacement due to isostatic recovery. Perhaps one also needs to make some correction for long term changes in the geoid as well.
However, a quick glance at the Wahl paper shows that even the revised Met Office statement to be incorrect irrespective of the definitions used:
"Sea level along the English Channel has already risen by about 12cm during the 20th century[12]; this is over and above the increases associated with sinking of the southern part of the UK due to isostatic adjustment[13] from the last Ice Age."
Table 1 of Wahl et al gives the long term relative sea level (RMSL) rates of change for different locations in the channel. The RMSL change is a combination of isostatic and absolute sea level changes and not that which is 'over and above the increases associated with sinking of the southern part of the UK due to isostatic adjustment'. The figures in Table 1 are as follows:
Brest: 1850-2011 1.3mm per year
Le Havre: 1993-2011 1.5mm per year
Dunkerque: 1993-2011 -0.8mm per year
Dover: 1980-2011 1.6mm per year
Southampton 1950-2011 1.6mm per year
Devonport 1993-2011 -0.9mm per year
Newlyn 1900-2011 1.8mm per year
I'm not fully up to date with isostatic adjustment rates but a cursory look at some references show that southern england is sinking at a rate which is on the order of 1 to 2mm per year depending on location. i.e. the rate of sea level rise measured at channel locations over and above that due to isostatic adjustment is on the order of 0.3 to 0.8mm per year (just looking at the longer term records above and taking an isostatic adjustment rate of 1mm per year). These rates are very different to those in the Met Office statement.
In their defines I note that Wahl et al show a huge range of absolute sea level rise rates for the channel (0.5mm per year to 2.25mm per year) based on different assumptions about isostatic adjustment rates. The errors are potentially enormous compared to the effect one is trying to measure.
Let us not forget the influence of geological process. Slow, for sure, but relentless. Much of the SE England coastline has been steadily accreting for centuries, despite the absolute MSL rise.Compare the Roman shoreline, the Cinque Port era shore line and the subsequent land locked status of these historic ports. Some has been assisted by marsh reclamation, but most is natural. Conversely, in Holland, we have both post depositional sedimentary compaction to consider, estimated in places in excess of 1mm/yr exacerbating subsidence, countered by new sediment accretion in the opposite sense.
The same mistakes plague the scaremongering in the Pacific in living coral atolls, in Bangladesh in an active delta top accretionary regime, etc.
Thanks, Paul, that's very interesting. I really can't see why the Met Office report quoted absolute sea level rise for the 20th century at all, only to compare it with relative sea level rise for the 1990 -2030 period. Especially as you say, the relative SLR for the 20th century is available and more reliably measured. In the first version of the report the Met Office even apparently added those numbers together!
Ruth Dixon's research is to be commended, along with Richard Betts for bringing the matter to the attention of the authors. We have gone from an apparent 700% acceleration in the rate of sea level rise, to absolutely zero compared with the global average of 3.2mm +/- 0.4 per annum for the last 20 years. Over 40 years that is 11.2mm to 14.4mm compared with the Met Offices estimate of 11-16cm. What they have done with some of the best computing power on earth is equivalent to a forecast I could do on a calculator in two minutes. That is to assume that the local tide gauges will catch up with the satellite data. It makes sense if you assume that the satellites are accurate.
Figures are at http://sealevel.colorado.edu/
http://mygardenpond.wordpress.com/2014/02/09/met-office-report-says-sea-levels-likely-to-rise-11-16-cm-by-2030/
Again, in geological perspective, the current rate of SL change is utterly unremarkable. To suggest by inference that it is otherwise, as the Metoffice clearly wish to portray, is disgraceful propaganda.
Meteorological Office, the clue is in the title - 'meteorological' and defined as:
"the study of the earth's atmosphere, esp of weather-forming processes and weather forecasting".
I actually would think that, making divinations about SLR, is far beyond the capabilities of the warmist civil servants in the MO. Moreover, SLR it is not relevant to casting the runes - ie, attempting to second guess the water spirits and Naiads/computer modelling.
Further, the MO is so far off the science reservation and trespassing far into the realms of advocacy, actually discussing what they think is the truth, is akin to believing Al Gore at face value, you know - the man who preaches about SLR and in terms of metres not millimetres but who and fairly recently invested in a beach front property..................
Harry Passfield; one of the key lessons from Fukushima has not really had much airing. Despite all the procedures, no-one recognised that circumstances had moved outside the design parameters. Everyone knew that the spent fuel ponds were holding multiple cores - 4 in one case I think. That was far outside the design case which was based on spent fuel being shipped out as soon as it had cooled enough for transport. Yet no-one stood back and said "hang on, those ponds were'nt designed for this; they are not built to containment standards and do not have the defence-in-depth of the main safety systems".
So, while I agree that perspective was lost over Fukushima, we need to be wary of putting too much faith in procedures, audits and the like which can fail to see the wood for the trees. One of the suggestions in the aftermath has been to import "red teams" from, say, the chemical industry to challenge the "groupthink" that can lead to problems.
BTW, for anyone interested, the full report makes impressive reading. The operators were heros. They stayed at their posts and did their level damned best to get things under control despite loss of communications and the knowledge that their families had probably been caught by the tsunami. They even took the batteries from their own cars to try and power some instruments.
According to Lawrence Livermore volcanoes are the cause of the 16 year "hiatus"
https://www.llnl.gov/news/newsreleases/2014/Feb/NR-14-02-13.html#.UwvdWoXm7Z5
Athelstan.
I don't do predictions, so no timescale, but logic dictates there will be a separation of the Meteorological Office and the Hadley Centre. Quite simply one is being denigrated by the other. One uses skill developed through experience and the interpretation of observational data benefiting all of our lives. The other contributes the confusion of an unproven hypothesis.
The imprinting of, and higher priority given to the "unproven hypothesis" is undoubtedly impacting upon the meteorological skill of the MO. A situation that will take at least a generation to rectify. That is a generation after observational weather forecasting and wishful hypothetical modeling are eventually separated.