Britain and the Sea: Since 1600

You could not be signed in. Sign In Forgot password? Don't have an account? Sign in via your Institution Sign in. Purchase Subscription prices and ordering Short-term Access To purchase short term access, please sign in to your Oxford Academic account above. This article is also available for rental through DeepDyve. Email alerts New issue alert. Receive exclusive offers and updates from Oxford Academic.

Related articles in Google Scholar. Citing articles via Google Scholar. Rethinking the Peruvian Experiment under Military Rule, ed. Carlos Aguirre and Paulo Drinot. Reading and Writing Travels: Women in the English Historical Review. The Ambiguities of Belief and Belonging: Catholicism and the Church of the East in the Sixteenth Century. However, these two reservations cannot be major ones: The complete set of positive correlations, of whatever magnitude, in Table 2 provides reassurance of a reasonable if inevitably imperfect procedure.

A validation of these findings can be made by comparison of the trends in MSL to those obtained from geological information near to the tide gauge stations. Uncertainties shown by the vertical error bars in a and b are the standard errors of computed trends in MSL given in Tables 1 and 2 , respectively. Uncertainties shown by the horizontal error bars are the 0. Best estimates of the rate of vertical land movement i. Evidence for correlation between tide gauge and geological data can be seen in Fig.

However, the correlation is at first sight less convincing than in studies of North Sea or Scandinavian data e. This would suggest that the addition of a decade of new tide gauge information has resulted in little improvement in agreement between the data sets. However, the correlation is improved in Fig. Simple correlations between points ignoring individual errors of 0. In spite of the apparent improvement in agreement between UK tide gauge and geological data sets, there are some reservations to be made. A first is that Fig. Rosyth was a UK Hydrographic Office gauge, the generally poorer quality of which was remarked on by Woodworth et al.

It is no longer operational. The Immingham tide gauge is known to be affected by density changes due to run-off from the Humber. With regard to Lerwick, the small amount of geological information available from the Shetlands and geodynamic models Hoppe ; Peltier et al. Consequently, it is unlikely that the Lerwick record would conform to the encouraging picture of Fig.

Stornoway's record will be of great interest when longer: Belfast offers the greatest potential for further study, with tide gauge charts extending back to the 19th century having been recently rediscovered in an archive. The distributions of Figs 4 a and b also indicate that tide gauge MSL trends are in general larger than those inferred from geological data by 1.

Although the shorter records have proved to be useful, there naturally continues to be most interest in the longer ones. One obtains similar conclusions as from Fig.

1. Muse Misbehaving!
2. Britain and the Sea.
3. 1509 - 1660?
4. Modifying Sprites and Midgets 2nd Edition;

The offset is 1. The most outlying of the five appears to be Newlyn, either because its tide gauge MSL trend is too low or its geological rate suggests too much submergence. In this case, the offset is 1.

1 Introduction

This is encouraging but it is clear that the strength of the evidence for better line-up comes from one station Aberdeen. Uncertainties shown by the vertical error bars in both a and b are the standard errors of computed trends in MSL given in Table 1. Uncertainties shown by the horizontal error bars in a are the 0. One can adopt 1. This estimate changes within a range to be expected from a 0. This value can be added back to the index to provide an average-UK curve since Fig. However, this rate has undoubtedly increased in recent years.

In addition, there are suggestions of an acceleration in the rate Chen et al. The elastic response of the solid Earth will have resulted in a redistribution of sea level, and thereby a potentially slightly smaller Greenland contribution to UK sea level than the global-average, depending upon which parts of the ice sheet have lost mass cf. The success of the use of the index leads to a reconsideration of the reasons for its temporal variability, and thereby for some of the variability in individual UK records.

This is an important topic as low-frequency variability affects both the value of a secular trend and its standard error. The correlation coefficients between the two series are 0. For the period after , the correlations increase slightly to 0. Linear regression yields regression coefficients of 9. The departures will arise from forcings e. This yields a ratio of A low-pass filtered version of the sea level index compared with the negative of representative UK air pressure.

The air pressure time-series has been scaled to have the same root-mean-square variability as the index. This follows from the fact that the model average sea level will be something like the regional IB response, the modelled sea level changes due to winds over the shelf being more spatially variable cf. In this case, UK-average model sea level was defined by the average of the Newlyn and Aberdeen information, Liverpool and Sheerness not being well represented in the model grid and North Shields excluded so as not to overweight the average with North Sea values.

Correlation coefficients of 0. Therefore, the non-IB character of much of the variability observed in the index extends beyond the UK [The UK index is too short to determine any relationship between British sea level and distant i. At decadal timescales at least there is no similarly strong relationship between UK sea level and Azores air pressure].

A large number of authors have tried to understand the various oceanographic and meteorological forcings responsible for low-frequency UK and European-Atlantic coast MSL variability e. Rossiter ; Thompson These include steric density changes, ocean circulation variability, winds and air pressures Pugh However, to our knowledge, such studies have not provided evidence for coherent UK or European-coastline variability such as we require. A complicating factor is that the time-series of many meteorological forcing terms are highly correlated.

For example, river run-off is known to be responsible for MSL variability in many parts of the world on seasonal and longer timescales e. Therefore, one might expect run-off or its proxy in rainfall to be a potential forcing of UK MSL also, although it might be less plausible for relatively open-ocean sites such as Newlyn than it would be for sites in river estuaries such as Sheerness.

Rainfall and air pressure changes in the UK are highly correlated on interannual timescales Woodworth Consequently, it is not surprising that a UK rain time-series computed from spatially averaged normalized variability for — obtained from the UK Met Office www.

However, a positive correlation does not confirm run-off or any other shelf parameter as a significant forcing factor for MSL. The best approach with regard to the role of run-off will be through advanced numerical modelling of shelf processes which are just beginning e. Nevertheless, one probably has to search for processes with larger spatial scales than the shelf, given that the decadal variability in the UK index has similarities to that in many other records along the European-Atlantic coastline Thompson ; Woodworth The coherent variability between most of them is evident, correlation coefficients between the UK index and other stations being north to south: Each record has been detrended over the period —, low-pass filtered with a 5-yr boxcar filter, and offset for presentation purposes.

Thompson described a simple model of change in zonal trans-Atlantic sea level gradient, such that sea level on the European coast would be proportional to the integral of distance times Ekman pumping , with distance measured eastwards from the western boundary.

• ADDITIONAL MEDIA.
• 1660 - 1815;
• News latest!

The distance term gives greater weight to Ekman pumping on the eastern boundary, which again implies an approximate relationship to the negative of local air pressure, and gives another example of correlated variables. Thompson explained that this process contributes to a greater extent at lower frequencies and is capable of simulating part of the drop in Newlyn MSL during the s fig.

Such physics is nowadays included in ocean and climate models.



For example, Hill et al. The model time-series for Newlyn is shown in Fig. Correlation coefficients with the index are 0. Although it is not possible at present to extend the modelling through the whole period of the index, it confirms that ocean circulation change is probably the main source of its low-frequency variability, and that ocean modelling offers the best possibility for its further understanding. MSL changes at Newlyn from the ocean model study of Hill et al.

The solid line shows the overall contribution from both ocean circulation and IB, while the dashed line shows the ocean circulation contribution only. The ordinate contains an arbitrary model offset. Whatever the reasons for variability in the index in Fig. These include a reduction in the rate of sea level change, or deceleration, after e. Douglas ; Woodworth et al. It has made use of a larger number of shorter sea level records than has been employed so far, to maximize the amount of available information, and has been based on an improved method for determination of UK sea level trends.

The changes observed are consistent with findings of previous analyses, although they are more precise. They suggest a pattern of UK coastal sea level change composed of spatially variable primarily north—south local vertical land movements, which can be inferred from either geological e.

Shennan and Horton, or geodetic data e. This overall picture is inevitably an approximate one, but it is gratifying that the consistency in interpretation of the different data sets tide gauge, geological, geodetic appears to have risen as their temporal and spatial coverage has increased. The comparison of tide gauge, geological and geodetic trends provides an estimate of 1. Some progress has also been made in understanding the reasons for variability of UK MSL on interannual and decadal timescales. An inability to account adequately for decadal variability results in greater uncertainty in the calculation of long-term sea level trends.

It is also a topic of interest in its own right. It has been demonstrated that much of it is related to air pressure change. However, it is not a simple relationship such as that implied by the local IB model or even by the shelf response to air pressures and winds. One finds a UK-average response to air pressure approximately three times that of the IB model. The large-scale air pressure and wind fields e. The modelling of four decades of ocean circulation change by Hill et al. It would be highly desirable for the ocean modelling to be taken further back to the start of the 20th century, should the required data sets of model forcing become available.

In addition, more local contributors to MSL variability such as run-off cannot as yet be excluded, and require study from runs of advanced shelf models e. The validity of the simple model of a regionally coherent sea level signal of ocean origin superimposed on a spatial pattern of local vertical land movement is important, in that it provides the most straightforward means for developing scenarios of future sea level change around the UK and their possible impacts cf. Projections for 21st century UK sea level change have in most studies been assumed to be similar to the global projections, and will necessarily remain so until fuller understanding of regional deviations from global-averages is obtained from improved atmosphere—ocean general circulation models.

Therefore, given that global projections in the two recent IPCC assessments are similar, if Fourth Assessment values are increased to allow for the dynamic response of the Greenland and Antarctic ice sheets to warming Church et al.

United Kingdom

Two reviewers provided excellent comments on a draft of this paper. Oxford University Press is a department of the University of Oxford. It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide. Sign In or Create an Account. Close mobile search navigation Article navigation. Trends in UK mean sea level revisited P.

Summary This paper presents estimates of rates of mean sea level MSL change around the UK, based on a larger tide gauge data set and more accurate analysis methods than have been employed so far. Sea level change , Global change from geodesy , Atlantic Ocean. View large Download slide.