scholarly journals Are tidal predictions a good guide to future extremes? – a critique of the Witness King Tides Project

2020 ◽  
Author(s):  
John Hunter
Keyword(s):  
North America ◽  
West Coast ◽  
East Coast ◽  
Tide Gauge ◽  
Tide Gauge Records ◽  
The West ◽  
The World ◽  
The Usa ◽  
Good Guide ◽  
Using Data

Abstract. An analysis of the viability of the Witness King Tides Project (hereafter called WKT) using data from the GESLA-2 database of quasi-global tide-gauge records is described. The results indicate regions of the world where WKT should perform well (e.g. the west coast of the USA) and others where it would not (e.g. the east coast of North America). Recommendations are made both for assessments that should be made prior to a WKT project, and also for an alternative to WKT projects.

scholarly journals Are tidal predictions a good guide to future extremes? – a critique of the Witness King Tides project

Ocean Science ◽  
2020 ◽  
Vol 16 (3) ◽  
pp. 703-714
Author(s):  
John Hunter
Keyword(s):  
North America ◽  
Sea Level ◽  
East Coast ◽  
Tide Gauge ◽  
Tide Gauge Records ◽  
The West ◽  
The World ◽  
The Usa ◽  
Good Guide ◽  
Using Data

Abstract. An analysis of the viability of the Witness King Tides project (hereafter called WKT) using data from the GESLA-2 database of quasi-global tide-gauge records is described. The results indicate regions of the world where a key criterion for a WKT project (that it be executed on a day of unusually high sea level) would likely be met (e.g. the west coast of the USA) and others where it would not (e.g. the east coast of North America). Recommendations are made both for assessments that should be made prior to a WKT project and also for an alternative to WKT projects.

scholarly journals Quantification of migrant hoverfly movements (Diptera: Syrphidae) on the West Coast of North America

2019 ◽  
Vol 6 (4) ◽  
pp. 190153 ◽  
Author(s):  
Myles H. M. Menz ◽  
Brian V. Brown ◽  
Karl R. Wotton
Keyword(s):  
North America ◽  
West Coast ◽  
Life Histories ◽  
East Coast ◽  
Seasonal Migration ◽  
Science Data ◽  
The West ◽  
Video Footage ◽  
San Luis ◽  
The Usa

The seasonal migration of huge numbers of hoverflies is frequently reported in Europe from mountain passes or spurs of land. The movement of such large numbers of beneficial insects is thought to provide significant ecosystem services in terms of pollination and pest control. Observations from the East Coast of the USA during the 1920s indicate the presence of migratory life histories among some hoverfly species there, but 90 years have now passed since the last reported observation of hoverfly migration in the USA. Here, we analyse video footage taken during a huge northward migration of hoverflies on 20 April 2017 on the West Coast of California. The quantification of migrant numbers from this footage allows us to estimate the passage of over 100 000 hoverflies in half an hour over a 200 m section of headland in Montaña de Oro State Park (San Luis Obispo County). Field collections and analysis of citizen science data indicate different species from the previously reported Eristalis tenax migrations on the East Coast of the USA and provide evidence for migration among North American hoverflies. We wish to raise awareness of this phenomenon and suggest approaches to advance the study of hoverfly migration in North America and elsewhere.

Origin Time of the 1854 Ansei–Tokai Tsunami Estimated from Tide Gauge Records on the West Coast of North America

2020 ◽  
Vol 91 (5) ◽  
pp. 2624-2630 ◽  
Author(s):  
Satoshi Kusumoto ◽  
Kentaro Imai ◽  
Ryoko Obayashi ◽  
Takane Hori ◽  
Narumi Takahashi ◽  
...  
Keyword(s):  
North America ◽  
San Francisco ◽  
Local Time ◽  
West Coast ◽  
San Diego ◽  
Arrival Time ◽  
Tide Gauge ◽  
The West ◽  
Origin Time ◽  
Tsunami Signal

Abstract We estimated the origin time of the 1854 Ansei–Tokai tsunami from the tsunami waveforms recorded at three tide gauge stations (Astoria, San Francisco, and San Diego) on the west coast of North America. The tsunami signal is apparent in the San Francisco and San Diego records, and the arrival time was 0–1 p.m. Greenwich Mean Time (GMT) on 23 December 1854, whereas the tsunami signal of Astoria is ambiguous, and the arrival time could not be determined from the waveform. The simulated waveforms on the basis of nonlinear dispersive wave theory by assuming an origin time of 0 a.m. GMT on 23 December arrived earlier than the observations. Cross-correlation functions between the observed and simulated waveforms recorded at San Francisco and San Diego showed a time gap between them of approximately 30 min. Based on these results, we concluded that the origin time of the 1854 Ansei–Tokai tsunami was approximately 00:30 a.m. GMT or 09:46 local time on 23 December. Our result is roughly consistent with reports by a Russian frigate anchored in Shimoda Bay, ranging the earthquake between 09:00 and 09:45 and the tsunami between 09:30 and 10:00. The earthquake was also reported in historical Japanese documents ranging from 8 and 10 o’clock in local time.

scholarly journals Monarch butterflies cross the Appalachians from the west to recolonize the east coast of North America

2010 ◽  
Vol 7 (1) ◽  
pp. 43-46 ◽  
Author(s):  
Nathan G. Miller ◽  
Leonard I. Wassenaar ◽  
Keith A. Hobson ◽  
D. Ryan Norris
Keyword(s):  
North America ◽  
Direct Evidence ◽  
East Coast ◽  
Gulf Coast ◽  
Danaus Plexippus ◽  
Early Spring ◽  
Eastern United States ◽  
The West ◽  
Monarch Butterflies ◽  
The Usa

Each spring, millions of monarch butterflies ( Danaus plexippus ) migrate from overwintering sites in Mexico to recolonize eastern North America. However, few monarchs are found along the east coast of the USA until mid-summer. Brower (Brower, L. P. 1996 J. Exp. Biol. 199, 93–103.) proposed that east coast recolonization is accomplished by individuals migrating from the west over the Appalachians, but to date no evidence exists to support this hypothesis. We used hydrogen ( δ D) and carbon ( δ 13 C) stable isotope measurements to estimate natal origins of 90 monarchs sampled from 17 sites along the eastern United States coast. We found the majority of monarchs (88%) originated in the mid-west and Great Lakes regions, providing, to our knowledge, the first direct evidence that second generation monarchs born in June complete a ( trans -) longitudinal migration across the Appalachian mountains. The remaining individuals (12%) originated from parents that migrated directly from the Gulf coast during early spring. Our results provide evidence of a west to east longitudinal migration and provide additional rationale for conserving east coast populations by identifying breeding sources.

scholarly journals Use of Oceanic Reanalysis to Improve Estimates of Extreme Storm Surge

2019 ◽  
Vol 36 (11) ◽  
pp. 2205-2219 ◽  
Author(s):  
Li Zhai ◽  
Blair Greenan ◽  
Richard Thomson ◽  
Scott Tinis
Keyword(s):  
Sea Level ◽  
Storm Surge ◽  
West Coast ◽  
Large Scale ◽  
Tide Gauge ◽  
Steric Effects ◽  
Tide Gauge Records ◽  
The West ◽  
Sea Level Variability

AbstractA storm surge hindcast for the west coast of Canada was generated for the period 1980–2016 using a 2D nonlinear barotropic Princeton Ocean Model forced by hourly Climate Forecast System Reanalysis wind and sea level pressure. Validation of the modeled storm surges using tide gauge records has indicated that there are extensive areas of the British Columbia coast where the model does not capture the processes that determine the sea level variability on intraseasonal and interannual time scales. Some of the discrepancies are linked to large-scale fluctuations, such as those arising from major El Niño and La Niña events. By applying an adjustment to the hindcast using an ocean reanalysis product that incorporates large-scale sea level variability and steric effects, the variance of the error of the adjusted surges is significantly reduced (by up to 50%) compared to that of surges from the barotropic model. The importance of baroclinic dynamics and steric effects to accurate storm surge forecasting in this coastal region is demonstrated, as is the need to incorporate decadal-scale, basin-specific oceanic variability into the estimation of extreme coastal sea levels. The results improve long-term extreme water level estimates and allowances for the west coast of Canada in the absence of long-term tide gauge records data.

scholarly journals Time Difference Between the 1854 CE Ansei–Tokai and Ansei–Nankai Earthquakes Estimated from Distant Tsunami Waveforms on the West Coast of North America

2021 ◽  
Author(s):  
Satoshi Kusumoto ◽  
Kentaro Imai ◽  
Takane Hori
Keyword(s):  
North America ◽  
San Francisco ◽  
West Coast ◽  
Tide Gauge ◽  
Historical Earthquakes ◽  
Time Difference ◽  
The West ◽  
Origin Time ◽  
Significant Difference ◽  
Tsunami Waveforms

Abstract We estimated the time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai earthquakes from tidal records of two tide gauge stations (San Francisco and San Diego) on the west coast of North America. The first signals of the Ansei–Tokai tsunami were apparent, whereas those of the Ansei–Nankai tsunami were obscured by the later waves of the Ansei–Tokai tsunami. Waveforms of the Ansei–Nankai tsunami simulated with non-linear dispersive wave theory by assuming an origin time of 07:00 GMT on 24 December arrived earlier than in the observations. The normalized root mean square and the misfit between the simulated and observed waveforms of the Ansei–Nankai tsunami showed a time difference between them of approximately 0.4 h. This finding suggests that the actual origin time of the Ansei–Nankai tsunami was approximately 07:24 GMT on 24 December. A previous study estimated the origin time of the Ansei–Tokai tsunami to be about 00:30 GMT on 23 December. Thus, we concluded that the time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai tsunamis was 30.9 h. Despite the significant difference in the time resolution between the seasonal timekeeping system used in Japan in 1854 and waveform digitization, our result is roughly in agreement with historical descriptions of the tsunamis, suggesting that such information can be effectively used to determine the origin times of historical earthquakes.

scholarly journals Searching for Franklin where he was ordered to go: Captain Erasmus Ommanney's sledging campaign to Cape Walker and beyond, spring 1851

Polar Record ◽  
2016 ◽  
Vol 52 (4) ◽  
pp. 474-498
Author(s):  
W. Barr
Keyword(s):  
North America ◽  
West Coast ◽  
East Coast ◽  
The West ◽  
Northwest Passage ◽  
Ice Conditions ◽  
To Come ◽  
Detailed Search ◽  
Northeast Coast

ABSTRACTSince the Admiralty's instructions to Captain Sir John Franklin for his attempt at a transit of the northwest passage in HMS Erebus and Terror in 1845 specified that he should proceed to Cape Walker at the northeastern tip of Russell Island, and head southwest from there to the waterways already explored along the mainland coast of North America, as far as ice conditions and any intervening land permitted, it was natural that the first search expedition to come within striking distance of Cape Walker, should make this one of the starting points of its detailed search. This was the squadron of Captain Horatio Austin that wintered off the northeast coast of Griffith Island in 1850–1851. Following his orders, in the spring of 1851 Captain Erasmus Ommanney of HMS Assistance set off with an impressive cavalcade of seven man-hauled sledges, most of them support sledges. From Cape Walker Lt. William Browne searched the east coast of Prince of Wales Island, that is the western shores of Peel Sound while Ommanney himself and Lt. Sherard Osborn searched the west coast of Prince of Wales Island, that is the east shore of McClintock Channel. No traces of Franklin's expedition were found. Their conclusions were that both McClintock Channel and Peel Sound were permanently blocked with ice, and that Franklin's ships could not have travelled south by either route. While the conclusion as regards McClintock Channel was absolutely correct, that with regard to Peel Sound was incorrect. This must have been the route whereby Erebus and Terror had reached the vicinity of King William Island, and the conclusion that Peel Sound never cleared of ice was very unfortunate in that the next search expedition dispatched by the Admiralty, that of Captain Sir Edward Belcher in 1852–1854 made no attempt to penetrate south, when it is possible that Peel Sound was clear of ice.

scholarly journals Nonlinear absolute sea-level patterns in the long-term-trend tide gauges of the West Coast of North America

2020 ◽  
Vol 9 (1) ◽  
pp. 382-397
Author(s):  
Alberto Boretti
Keyword(s):  
North America ◽  
Sea Level ◽  
West Coast ◽  
Tide Gauge ◽  
Relative Rate ◽  
Tide Gauges ◽  
The West ◽  
The Absolute ◽  
Long Term Trend

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.

scholarly journals Coastal sea level response to the tropical cyclonic forcing in the northern Indian Ocean

Ocean Science ◽  
2015 ◽  
Vol 11 (1) ◽  
pp. 159-173 ◽  
Author(s):  
P. Mehra ◽  
M. Soumya ◽  
P. Vethamony ◽  
K. Vijaykumar ◽  
T. M. Balakrishnan Nair ◽  
...  
Keyword(s):  
Sea Level ◽  
West Coast ◽  
Arabian Sea ◽  
East Coast ◽  
Tide Gauge ◽  
Meteorological Data ◽  
Linear Regression Analysis ◽  
The West ◽  
Cyclonic Storm ◽  
Sea Level Oscillations

Abstract. The study examines the observed storm-generated sea level variation due to deep depression (event 1: E1) in the Arabian Sea from 26 November to 1 December 2011 and a cyclonic storm "THANE" (event 2: E2) over the Bay of Bengal during 25–31 December 2011. The sea level and surface meteorological measurements collected during these extreme events exhibit strong synoptic disturbances leading to storm surges of up to 43 cm on the west coast and 29 cm on the east coast of India due to E1 and E2. E1 generated sea level oscillations at the measuring stations on the west coast (Ratnagiri, Verem and Karwar) and east coast (Mandapam and Tuticorin) of India with significant energy bands centred at periods of 92, 43 and 23 min. The storm surge is a well-defined peak with a half-amplitude width of 20, 28 and 26 h at Ratnagiri, Verem and Karwar, respectively. However, on the east coast, the sea level oscillations during Thane were similar to those during calm period except for more energy in bands centred at periods of ~ 100, 42 and 24 min at Gopalpur, Gangavaram and Kakinada, respectively. The residual sea levels from tide gauge stations in Arabian Sea have been identified as Kelvin-type surges propagating northwards at a speed of ~ 6.5 m s−1 with a surge peak of almost constant amplitude. Multi-linear regression analysis shows that the local surface meteorological data (daily mean wind and atmospheric pressure) is able to account for ~ 57 and ~ 69% of daily mean sea level variability along the east and west coasts of India. The remaining part of the variability observed in the sea level may be attributed to local coastal currents and remote forcing.

scholarly journals Time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai earthquakes estimated from distant tsunami waveforms on the west coast of North America

2022 ◽  
Vol 9 (1) ◽  
Author(s):  
Satoshi Kusumoto ◽  
Kentaro Imai ◽  
Takane Hori
Keyword(s):  
North America ◽  
San Francisco ◽  
West Coast ◽  
Tide Gauge ◽  
Historical Earthquakes ◽  
Time Difference ◽  
The West ◽  
Origin Time ◽  
Significant Difference ◽  
Tsunami Waveforms

AbstractWe estimated the time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai earthquakes from tidal records of two tide gauge stations (San Francisco and San Diego) on the west coast of North America. The first signals of the Ansei–Tokai tsunami were apparent, whereas those of the Ansei–Nankai tsunami were obscured by the later waves of the Ansei–Tokai tsunami. Waveforms of the Ansei–Nankai tsunami simulated with nonlinear dispersive wave theory by assuming an origin time of 07:00 GMT on 24 December arrived earlier than in the observations. The normalized root mean square and the misfit between the simulated and observed waveforms of the Ansei–Nankai tsunami showed a time difference between them of approximately 0.4 h. This finding suggests that the actual origin time of the Ansei–Nankai tsunami was approximately 07:24 GMT on 24 December. A previous study estimated the origin time of the Ansei–Tokai tsunami to be about 00:30 GMT on 23 December. Thus, we concluded that the time difference between the 1854 CE Ansei–Tokai and Ansei–Nankai tsunamis was 30.9 h. Despite the significant difference in the time resolution between the seasonal timekeeping system used in Japan in 1854 and waveform digitization, our result is roughly in agreement with historical descriptions of the tsunamis, suggesting that such information can be effectively used to determine the origin times of historical earthquakes.

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