scholarly journals Variability of Winter Storminess in the Eastern United States during the Twentieth Century from Tide Gauges

2013 ◽  
Vol 26 (23) ◽  
pp. 9713-9726 ◽  
Author(s):  
Philip R. Thompson ◽  
Gary T. Mitchum ◽  
Cedric Vonesch ◽  
Jianke Li

Interannual to multidecadal variability of winter storminess in the eastern United States was studied using water level measurements from coastal tide gauges. The proximity to the coast of the primary winter storm track in the region allows the use of tide gauges to study temporal modulations in the frequency of these storms. Storms were identified in high-passed, detided sea level anomalies in 20 gauges from all coasts of North America to assess variability in winter storminess along particular storm tracks. The primary result is a significant multidecadal increase in the number of storms affecting the southeastern United States from the early to late twentieth century. The authors propose that this change is due to an increased tendency for the jet stream to meander south over the eastern United States since the 1950s. This mechanism is supported by long-term changes in the large-scale sea level pressure pattern over North America. The nature of the multidecadal change in storm frequency is unclear, because limited tide gauge record lengths prevent distinguishing between a trend and an oscillation.

Author(s):  
F.N Teferle ◽  
R.M Bingley ◽  
S.D.P Williams ◽  
T.F Baker ◽  
A.H Dodson

Researchers investigating climate change have used historical tide-gauge measurements from all over the world to investigate the changes in sea-level that have occurred over the last century or so. However, such estimates are a combination of any true sea-level variations and any vertical movements of the land at the specific tide-gauge. For a tide- gauge record to be used to determine the climate related component of changes in sea-level, it is therefore necessary to correct for the vertical land movement component of the observed change in sea-level. In 1990, the Institute of Engineering Surveying and Space Geodesy and Proudman Oceanographic Laboratory started developing techniques based on the Global Positioning System (GPS) for measuring vertical land movements (VLM) at tide-gauges in the UK. This paper provides brief details of these early developments and shows how they led to the establishment of continuous GPS (CGPS) stations at a number of tide-gauges. The paper then goes on to discuss the use of absolute gravity (AG), as an independent technique for measuring VLM at tide-gauges. The most recent results, from CGPS time-series dating back to 1997 and AG time-series dating back to 1995/1996, are then used to demonstrate the complementarity of these two techniques and their potential for providing site-specific estimates of VLM at tide-gauges in the UK.


2020 ◽  
Author(s):  
Peter Thejll

<p>Information on extremes of the sea-level is obtained from tide-gauge<br>records.  Such records may have gaps.</p><p>Estimates of potential changes in the size and/or frequency of sea-level<br>extremes are hampered by long gaps, or when just the high extremes are<br>missing due, e.g. to equipment failure.</p><p>Methods used for filling such gaps can be based on having multiple<br>records from gauges near each other; but what to do if there is<br>only one record? This problem can typically occur when old tide-gauge<br>records are used -- the use of multiple recorders at the same place is<br>more wide-spread today. However, especially older and therefore longer<br>records hold the key to obtaining long-baseline insights into the temporal<br>evolution of extreme tides and thus impacts of e.g. climate change.</p><p>In this work, we review and assess methods for gap filling. We asses using<br>the 'known truth' method, i.e. by applying realistic gaps to complete<br>gauge records and reconstructing and then comparing errors calculated as<br>the diffrence between modelled and actual values.  We compare a simple<br>harmonic model fit method to various spline methods as well as Neural<br>network and deep learning approches.  We also test a hybrid method<br>which uses not just tide-gauge data but also air pressure readings<br>from a meteorological station near the tide-gauge.</p><p>We then attempt to fill in the missing maxima of the Esbjerg, Denmark<br>hourly tide-gauge record since 1889. Particularly, before 1910 the maxima<br>above 300 cm are missing (Bijl, et al., 1999), and we try to fill these in.</p>


Author(s):  
Laury Miller ◽  
Bruce C Douglas

Both the rate and causes of twentieth century global sea-level rise (GSLR) have been controversial. Estimates from tide-gauges range from less than one, to more than two millimetre yr −1 . In contrast, values based on the processes mostly responsible for GSLR—mass increase (from mountain glaciers and the great high latitude ice masses) and volume increase (expansion due to ocean warming)—fall below this range. Either the gauge estimates are too high, or one (or both) of the component estimates is too low. Gauge estimates of GSLR have been in dispute for several decades because of vertical land movements, especially due to glacial isostatic adjustment (GIA). More recently, the possibility has been raised that coastal tide-gauges measure exaggerated rates of sea-level rise because of localized ocean warming. Presented here are two approaches to a resolution of these problems. The first is morphological, based on the limiting values of observed trends of twentieth century relative sea-level rise as a function of distance from the centres of the ice loads at last glacial maximum. This observational approach, which does not depend on a geophysical model of GIA, supports values of GSLR near 2 mm yr −1 . The second approach involves an analysis of long records of tide-gauge and hydrographic ( in situ temperature and salinity) observations in the Pacific and Atlantic Oceans. It was found that sea-level trends from tide-gauges, which reflect both mass and volume change, are 2–3 times higher than rates based on hydrographic data which reveal only volume change. These results support those studies that put the twentieth century rate near 2 mm yr −1 , thereby indicating that mass increase plays a much larger role than ocean warming in twentieth century GSLR.


2021 ◽  
Vol 10 (1) ◽  
pp. 1-15
Author(s):  
Alberto Boretti

Abstract The paper provides an estimate of the latest relative and absolute rates of rise and accelerations of the sea levels for the East Coast of North America. The computation is based on the long-term trend (LTT) tide gauge records of the relative sea levels and the Global Navigation Satellite System (GNSS) time series of the absolute position of fixed dome nearby the tide gauges. The GNSS result is used to infer the subsidence or uplift of the tide gauge instrument. The data of 33 LTT tide stations with more than 80 years of data are shown. The average relative sea-level rise is +2.22 mm/yr. subjected to a small, positive average acceleration of +0.0027 mm/yr2. The average absolute velocity of the tide gauge instruments is −0.52 mm/yr. translating in an average absolute sea-level rise of +1.70 mm/yr. This is the first paper publishing a comprehensive survey of the absolute sea-level rates of rise along the East Coast of North America using the reliable information of relative sea-level rates of rise from LTT tide gauges, plus the absolute subsidence rates from GNSS antennas that are close to the tide gauges installations.


2020 ◽  
Vol 9 (1) ◽  
pp. 382-397
Author(s):  
Alberto Boretti

AbstractThe research issue of which are the present relative and absolute rates of rise and accelerations for North America is here addressed. The data of the 20 long-term-trend (LTT) tide stations of the West Coast of North America with more than 80 years of recorded data are shown. The absolute rates of rise are computed by considering the absolute vertical velocity of Global Navigation Satellite System (GNSS) antennas near the tide gauges, and the relative rate of sea-level rise from the tide gauge signals. The 20 LTT stations along the West Coast of North America show an average relative rate of rise of -0.38 mm/yr., an average acceleration of +0.0012 mm/yr2, and an average absolute rate of rise of +0.73 mm/yr. This is the first paper publishing a comprehensive survey of the absolute sea-level rates of rise along the West Coast of North America using the reliable information of relative sea-level rates of rise from LTT tide gauges plus the absolute subsidence rates from different GNSS antennas close to the tide gauge installations.


2016 ◽  
Vol 5 (2) ◽  
Author(s):  
Albert Parker

AbstractThe tide gauges measure the local oscillations of the sea level vs. the tide gauge instrument. The tide gauge instrument is generally subjected to the general subsidence or uplift of the nearby inland, plus some additional subsidence for land compaction and other localised phenomena. The paper proposes a non-linear model of the relative sea level oscillations including a long term trend for the absolute sea level rise, another term for the subsidence of the instrument, and finally a sinusoidal approximation for the cyclic oscillations of periodicities up to decades. This non-linear model is applied to the tide gauges of China. The paper shows that the limited information available for China does not permit to infer any proper trend for the relative rates of rise, as the tide gauge records are all short or incomplete and the vertical movement of the tide gauge instruments is unassessed. The only tide gauge record of sufficient length that may be assembled for China is obtained by combining the North Point and Quarry Bay tide gauges in Hong Kong (NPQB). This NQPB composite tide gauge record is shown to have similarities with the tide gauge records of Sydney, equally in the West pacific, and San Diego, in the east Pacific, oscillating about the longer term trend mostly determined by the local subsidence. As it is very well known that China generally suffers of land subsidence, and the tide gauge installations may suffer of additional subsidence vs. the inland, it may be concluded from the analysis of the other worldwide tide gauges that the sea levels of China are very likely rising about the same amount of the subsidence of the tide gauges, with the sea level acceleration component still negligible.


1992 ◽  
Vol 29 (11) ◽  
pp. 2418-2425 ◽  
Author(s):  
A. Mark Tushingham

Churchill, Manitoba, is located near the centre of postglacial uplift caused by the Earth's recovery from the melting of the Laurentide Ice Sheet. The value of present-day uplift at Churchill has important implications in the study of postglacial uplift in that it can aid in constraining the thickness of the ice sheet and the rheology of the Earth. The tide-gauge record at Churchill since 1940 is examined, along with nearby Holocene relative sea-level data, geodetic measurements, and recent absolute gravimetry measurements, and a present-day rate of uplift of 8–9 mm/a is estimated. Glacial isostatic adjustment models yield similar estimates for the rate of uplift at Churchill. The effects of the tide-gauge record of the diversion of the Churchill River during the mid-1970's are discussed.


IoT ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 17-32
Author(s):  
Philip Knight ◽  
Cai Bird ◽  
Alex Sinclair ◽  
Jonathan Higham ◽  
Andy Plater

A low-cost “Internet of Things” (IoT) tide gauge network was developed to provide real-time and “delayed mode” sea-level data to support monitoring of spatial and temporal coastal morphological changes. It is based on the Arduino Sigfox MKR 1200 micro-controller platform with a Measurement Specialties pressure sensor (MS5837). Experiments at two sites colocated with established tide gauges show that these inexpensive pressure sensors can make accurate sea-level measurements. While these pressure sensors are capable of ~1 cm accuracy, as with other comparable gauges, the effect of significant wave activity can distort the overall sea-level measurements. Various off-the-shelf hardware and software configurations were tested to provide complementary data as part of a localized network and to overcome operational constraints, such as lack of suitable infrastructure for mounting the tide gauges and for exposed beach locations.


2021 ◽  
Author(s):  
Inger Bij de Vaate ◽  
Henrique Guarneri ◽  
Cornelis Slobbe ◽  
Martin Verlaan

<p>The existence of seasonal variations in major tides has been recognized since decades. Where Corkan (1934) was the first to describe the seasonal perturbation of the M2 tide, many others have studied seasonal variations in the main tidal constituents since. However, most of these studies are based on sea level observations from tide gauges and are often restricted to coastal and shelf regions. Hence, observed seasonal variations are typically dominated by local processes and the large-scale patterns cannot be clearly distinguished. Moreover, most tide models still perceive tides as annually constant and seasonal variation in tides is ignored in the correction process of satellite altimetry. This results in reduced accuracy of obtained sea level anomalies. </p><p>To gain more insight in the large-scale seasonal variations in tides, we supplemented the clustered and sparsely distributed sea level observations from tide gauges by the wealth of data from satellite altimeters. Although altimeter-derived water levels are being widely used to obtain tidal constants, only few of these implementations consider seasonal variation in tides. For that reason, we have set out to explore the opportunities provided by altimeter data for deriving seasonal modulation of the main tidal constituents. Different methods were implemented and compared for the principal tidal constituents and a range of geographical domains, using data from a selection of satellite altimeters. Specific attention was paid to the Arctic region where seasonal variation in tides was expected to be significant as a result of the seasonal sea ice cycle, yet data availability is particularly limited. Our study demonstrates the potential of satellite altimetry for the quantification of seasonal modulation of tides and suggests the seasonal modulation to be considerable. Already for M2 we observed changes in tidal amplitude of the order of decimeters for the Arctic region, and centimeters for lower latitude regions.</p><p> </p><div>Corkan, R. H. (1934). An annual perturbation in the range of tide. <em>Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character</em>, <em>144</em>(853), 537-559.</div>


Sign in / Sign up

Export Citation Format

Share Document