Two analytic models for hyperbolic geometry

Call number: LD2668 .R4 1963 W91

Celebrating 100 years of tidal science on Merseyside

To mark the 100th anniversary of the Liverpool Tidal Institute (LTI), a celebratory meeting on ‘The ocean tide and the Port of Liverpool’ was held at the Merseyside Maritime Museum in May 2019. The LTI’s buildings at Bidston Observatory in Birkenhead are a well known local landmark, so the meeting attracted great interest from the general public as well as from academia, and there were almost 200 people in the audience

Tide prediction machines at the Liverpool Tidal Institute

The 100th anniversary of the Liverpool Tidal Institute (LTI) was celebrated during 2019. One aspect of tidal science for which the LTI acquired a worldwide reputation was the development and use of tide prediction machines (TPMs). The TPM was invented in the late 19th century, but most of them were made in the first half of the 20th century, up until the time that the advent of digital computers consigned them to museums. This paper describes the basic principles of a TPM, reviews how many were constructed around the world and discusses the method devised by Arthur Doodson at the LTI for the determination of harmonic tidal constants from tide gauge data. These constants were required in order to set up the TPMs for predicting the heights and times of the tides. Although only 3 of the 30-odd TPMs constructed were employed in operational tidal prediction at the LTI, Doodson was responsible for the design and oversight of the manufacture of several others. The paper demonstrates how the UK, and the LTI and Doodson in particular, played a central role in this area of tidal science

San Francisco Bay Area KIPP Schools: A Study of Early Implementation and Achievement: Final Report

Examines the achievement results and operations of five Knowledge Is Power Program middle schools to assess the program's effectiveness, the role of leadership, implementation of the KIPP culture, design of curricula and instruction, and lessons learned

Long-term and recent changes in sea level in the Falkland Islands

Mean sea level measurements made at Port Louis in the Falkland Islands in 1981-2, 1984 and 2009, together with values from the nearby permanent tide gauge at Port Stanley, have been compared to measurements made at Port Louis in 1842 by James Clark Ross. The long-term rate of change of sea level is estimated to have been +0.75 ± 0.35 mm/year between 1842 and the early 1980s, after correction for air pressure effects and for vertical land movement due to Glacial Isostatic Adjustment (GIA). The 2009 Port Louis data set is of particular importance due to the availability of simultaneous information from Port Stanley. The data set has been employed in two ways, by providing a short recent estimate of mean sea level itself, and by enabling the effective combination of measurements at the two sites. The rate of sea level rise observed since 1992, when the modern Stanley gauge was installed, has been larger at 2.51 ± 0.58 mm/year, after correction for air pressure and GIA. This rate compares to a value of 2.79 ± 0.42 mm/year obtained from satellite altimetry in the region over the same period. Such a relatively recent acceleration in the rate of sea level rise is consistent with findings from other locations in the southern hemisphere and globall

The tidal measurements of James Cook during the voyage of the Endeavour

The main priority of the first of James Cook's famous voyages of discovery was the observation of the transit of Venus at Tahiti. Following that, he was ordered to embark on a search for new lands in the South Pacific Ocean. Cook had instructions to record as many aspects of the environment as possible at each place that he visited, including the character of the tide. This paper makes an assessment of the quality of Cook's tidal observations using modern knowledge of the tide, and with an assumption that no major tidal changes have taken place during the past two and half centuries. We conclude that Cook's tidal measurements were accurate in general to about 0.5 ft (15 cm) in height and 0.5 h in time. Those of his findings which are less consistent with modern insight can be explained by the short stays of the Endeavour at some places. Cook's measurements were good enough (or unique enough) to be included in global compilations of tidal information in the 18th century and were used in the 19th century in the construction of the first worldwide tidal atlases. In most cases, they support Cook's reputation as a good observer of the environment