Effect of altitude on the variation of pre-monsoon thunderstorm frequency during periods of higher sun spot number

The variation of pre-monsoon Thunder Storm Frequency (TSF) depending on the appearance of sun spot (S.S.) have been studied for the period 1955-80 for total 96 stations distributed allover India. For most of the stations we can identify a critical S.S. number in the neighbourhood of mean S.S. 140 above which a clear increasing or decreasing trend of mean TSF is observed with increase of S.S. number. It has also been seen that for almost all the stations having altitude greater than 280m, TSF increases with increase of S.S. number provided it is greater than the critical number.

Tone painting and painting tones: A follow-up study of listeners’ audiovisual responses to Beethoven’s Thunder Storm

This follow-up pilot study investigates the effect of a six-month analysis course, during which college music majors learned to see the meaning of music as being essentially intra-musical. The study aims to explore relationships between intra- and extra-musical perceptions among subjects ( N = 33) while listening to Beethoven’s Thunder Storm ( Pastoral Symphony, 4th movement). During pre- and post-intervention sessions, listeners represented the music via self-invented audiovisual products (AVPs) and related notes. Four systems of conceptualization emerged: Random responses (category-R), reflecting no reference to the music; Associative contents (category-A), suggesting extra-musical interpretations; Compound responses (category-C), combining extra- and intra-musical contents; Intra-musical contents (category-I), referring to purely musical properties. A scale of 4-6-8-10 grades for the respective categories R-A-C-I was established, with the highest score for category-I which reflects fulfilment of the course objective. By comparing between pre- and post-intervention AVPs, results show an insignificant increase in I-responses (zero to 9.5%) and 52.6% of no conceptual change through phases. The most prominent response is the extra-musical (68%) often at both pre- and post- phases (47%). The study empowers the position that classical music evokes referential contents, which should be given as much attention in teaching and learning music as ‘analytical’ properties of sound.

Lightning Effect on Scaled Protected and un-Protected Building Structures and the Air Terminal Bypasses

Lightning strikes affect the building structures by producing high electric field on the surface and around the building structure. Lightning air terminal is a traditional enemy of the thunder storm as it captures the lightning flashes. Effect of lightning flash on the building structure when the lightning air terminal was not installed and when it was installed on different building structure was studied in this paper. Similarly most of the time Lightning Air Terminal (LAT) bypasses take palce on different building structures and thus a lot of building structures get damage. The phenomenon of bypasses was also studied in this paper. When thunder storm strikes a building the electric field effect is propagated throughout the building surface and it damages the entire building. When the air terminal is places on the corners/edges it captures the lightning flashes on certain points and discharges it into the ground and the building remains safe. This phenomenon was studied in detail in this paper and it was proved that by installing the air terminal the remaining building structure was safe and the electric field intensity was concentrated on the installed air terminal rather than the whole roof top and the rest of the building.

Studi Kejadian Thunder Storm Pada Saat Hujan Lebat (Studi Kasus Kota Pontianak dan Sekitarnya)

Telah dilakukan penelitian untuk mempelajari tentang hubungan kejadian petir dengan curah hujan untuk mengetahui masa matang hingga punah suatu awan pada saat terjadi hujan lebat di kota Pontianak. Data yang digunakan pada penelitian ini adalah data kejadian petir yang diperoleh dari lihgtning detector dan data curah hujan hellman tahun 2012 s.d 2013 di stasiun meteorologi Supadio, stasiun maritim Pontianak dan stasiun klimatologi Siantan. Analisis kejadian petir pada saat hujan lebat digunakan untuk mengetahui fase pertumbuhan awan, dimana untuk setiap curah hujan lebih dari 5 mm/15 menit dikategorikan sebagai fase matang, sebelum dan setelahnya masuk dalam fase pertumbuhan dan fase punah. Hasil penelitian menunjukan bahwa nilai korelasi tertinggi antara kejadian petir dan curah hujan terjadi pada tanggal 10 Oktober 2012 di Stasiun klimatologi Siantan dengan nilai r=0,82 dan korelasi terendah terjadi pada tanggal 15 November 2012 di stasiun meteorologi Supadio dengan nilai r=0,61.

Localized Coherence of Freak Waves

This paper investigates in detail a possible mechanism of energy convergence leading to freak waves. We give examples of a freak wave as a (weak) pseudo-maximal wave to illustrate the importance of phase coherence. Given a time signal at a certain position, we identify parts of the time signal with successive high amplitudes, so-called group events, that may lead to a freak wave using wavelet transform analysis. The local coherence of the critical group event is measured by its time spreading of the most energetic waves. Four types of signals have been investigated; dispersive focussing, normal sea condition, thunder storm condition, and an experimental irregular wave. In all cases presented in this paper, it is shown that a high correlation exists between the local coherence and the appearance of a freak wave. This makes it plausible that freak waves can be developed by local interactions of waves in a wave group and that the effect of waves that are not in the immediate vicinity is minimal. This indicates that a local coherence mechanism within a wave group can be one mechanism that leads to the appearance of a freak wave.

Chapter XXVII: Return to Stonington—Thunder-storm—Emigrants—Illness—Alexandria

A fortnight passed rapidly away in this great city, and, doubtless, there was still much left unseen when we quitted it, according to previous arrangement, to return to our friends in Maryland. We came back by a different route, going by land from...