Heat, moisture, and momentum budgets of a midlatitude squall line with a trailing stratiform region

October 1989.Also issued as author's thesis (M.S.) -- Colorado State University, 1989.Includes bibliographical references.Rawinsonde data from the 1985 O-K PRE-STORM project are used to calculate the heat, moisture and momentum budgets during the late mature through decaying stages of a large squall line system that occurred on 10-11 June. Rawinsondes are composited to decrease station spacing and allow better resolution of mesoscale features within t he system. Low-level radar data and surface accumulated rainfall reports are used to partition the convective system into convective line and stratiform regions, and to check the accuracy of the heat and moisture budgets. Despite the compositing approach, the spacing of the sounding data is inadequate to fully resolve motions in the convective line. The resolution is marginally adequate, however, for motions in the stratiform region. This squall line had a pronounced rear-inflow jet that advanced toward the front of the system with time, and strong front-to-rear flow at higher levels. Convergence was strong in mid-levels within the stratiform region where the opposing jets met. Divergence at the top of the system weakened markedly as the system decayed. Upward vertical motion also weakened, and the vertical axes of strongest convective line ascent and descent within the stratiform region became increasingly sloped over time. Heating rates within the overall convective system peaked around 400 mb near the convective line region, and decreased in intensity from over 13°C h - 1 to less than 5°C h - 1 between 0300 and 0730 UTC. Cooling occurred in the stratiform region and was most intense just behind the back edge of the radar echo around 550 mb, just above the melting level. Peak cooling rates increased from over 3°C h- 1 to 6°C h- 1 between 0300 and 0600 UTC, and then decreased to 4°C h - 1 at 0730 UTC. Drying rates peaked also in the convective line region, but at lower levels than the heating rates. Moistening due to evaporation was typically strongest around 700 mb in the stratiform region. Vertical integrations of both budgets produced rainfall rates generally close to the observed ones for averages over the entire system. However, precipitation in the leading convective line was underestimated by 40% , due in large part to inadequate sounding data resolution. In the stratiform region the diagnosed precipitation rates underestimated the observed by as much as 2 or 3 _mm h-1 as the system decayed. Radar reflectivity data showed that the rearward transport · of hydrometeors could add as much as 2 - 4 mm h- 1 to the diagnosed stratiform rates. The transport, in addition to liquid water storage, could account for the underestimations in the diagnosed rates. The fact that the underestimate in the stratiform region did not occur at 0300 UTC suggests that vertical motion in the convective line was aliased into the stratiform region significantly at this earlier time. Less aliasing may have occurred later as the leading line weakened and the separation between it and the stratiform region increased. In general, the location of predicted rainfall and the temporal trend of the heating and moistening rates matched observations well, establishing the credibility of the budget studies. A strong mesolow existed at mid-levels within the stratiform region of the system, and the momentum budget showed pressure gradient accelerations were generally front-to-rear. Coriolis accelerations and internal turbulent stresses generally opposed the pressure gradient, and the resulting observed accelerations became weak, with increasing rear-to-front acceleration at high levels as the system weakened. The pressure gradient increased the vertical shear of the component of the wind normal to the line, but as the system decayed, the turbulent stresses began to oppose the increase in shear.Supported by the National Science Foundation under grant no. ATM-8711649, and a National Science Foundation graduate fellowship

KEBERLANJUTAN MATERIAL BAMBU PADA BANGUNAN AULA BAMBU BUMI PEMUDA RAHAYU

Abstract - The issue of global warming strongly encourages architects to use sustainable materials to preserve nature. Bamboo material is an ecological and sustainable material. Bamboo is also predicted as a future material. The strengths and advantages of bamboo are very likely to be used as a building construction material. Unfortunately, it is not uncommon for bamboo material to be used inappropriately so that it does not optimize the ecological and sustainable properties of bamboo. The object of study chosen was the Bumi Pemuda Rahayu bamboo hall. This object is close to the concept of sustainability as seen from the function of the building, which is a co-creating space that prioritizes sustainability-related activities. This research uses qualitative-quantitative methods that will compare the theory regarding the concept of sustainability of materials related to the building material life cycle with the data obtained. The concept will be divided into three aspects, namely design aspects, construction aspects, and maintenance and renovation aspects. These three aspects can be examined by knowing the object data related to these aspects. The results of the study will answer whether the use of bamboo material in the object of study is in accordance with the concept of sustainability of the bamboo material. The analysis of the design stage pays attention to material selection, material preservation, how to optimize the age of bamboo and the selection of a structural system. The construction stage is analyzed by considering the type of connection used. The maintenance and renovation phases are analyzed by paying attention to how to renovate the bamboo structure and post-construction maintenance of the building. This building is appropriate in choosing the type of material, applying preservation of bamboo materials, and successfully preventing bamboo from environmental influences in order to reach its optimal age. In terms of structural system selection, this building is also appropriate by applying the arc rod structural system. Bolted joints are appropriate for complex structural systems, it's just that there must be special treatment at the base of the arc structure that receives the greatest load due to cracks. Renovation and maintenance aspects must be considered again because this building will have difficulty if you have to do renovations, especially on the arc structure. Maintenance that is rarely performed can also reduce the life of the building.   Key Words: bamboo, sustainable materials, Bumi Pemuda RahayuAbstrak - Isu pemanasan global sangat mendorong arsitek untuk menggunakan material yang berkelanjutan untuk menjaga kelestarian alam. Material bambu adalah material ekologis dan berkelanjutan. Bambu juga digadang-gadang sebagai material masa depan. Kekuatan dan kelebihan yang dimiliki bambu sangat mungkin untuk dimanfaatkan sebagai material konstruksi bangunan. Sayangnya, tidak jarang material bambu digunakan dengan tidak tepat sehingga tidak mengoptimalkan sifat ekologis dan berkelanjutan dari bambu. Objek studi yang dipilih adalah aula bambu Bumi Pemuda Rahayu. Objek tersebut dekat dengan konsep keberlanjutan dilihat dari fungsi bangunan tersebut yang merupakan co-creating space yang mengedepankan kegiatan-kegiatan terkait sustainability. Penelitian menggunakan metode kualitatif-kuantitatif yang akan membandingkan teori mengenai konsep keberlanjutan material terkait building material life cycle dengan data yang didapat. Konsep tersebut akan dibedah menjadi tiga aspek, yaitu aspek desain, aspek konstruksi, dan aspek perawatan dan renovasi. Ketiga aspek tersebut dapat ditelaah dengan mengetahui data objek terkait aspek tersebut. Hasil penelitian akan menjawab apakah penggunaan material bambu pada objek studi sudah sesuai dengan konsep keberlanjutan material bambu. Analisis tahap desain memperhatikan pemilihan material, preservasi material, cara mengoptimalkan usia bambu dan pemilihan sistem struktur. Tahap konstruksi dianalisis dengan memperhatikan jenis sambungan yang digunakan. Tahap perawatan dan renovasi dianalisis dengan memperhatikan cara merenovasi struktur bambu dan perawatan pasca konstruksi pada bangunan. Bangunan ini tepat dalam  memilih jenis material, penerapan preservasi material bambu, dan berhasil menghindarkan bambu dari pengaruh lingkungan agar mencapai usia optimal. Secara pemilihan sistem struktur, bangunan ini juga tepat dengan menerapkan sistem struktur rangka batang busur. Sambungan baut tepat digunakan untuk sistem struktur yang kompleks, hanya saja harus ada perlakuan khusus pada bagian pangkal struktur busur yang menerima beban paling besar karena terdapat retak. Aspek renovasi dan perawatan harus diperhatikan lagi karena bangunan ini akan kesulitan jika harus melakukan renovasi, terutama pada bagian struktur busur. Perawatan yang jarang dilakukan juga dapat mengurangi usia bangunan.   Kata Kunci: bambu, material berkelanjutan, Bumi Pemuda Rahay