scholarly journals KAJIAN KONDISI ATMOSFER DI WILAYAH INDONESIA SAAT PERIODE AKTIFNYA BADAI TROPIS KAI-TAK

2019 ◽  
Vol 3 ◽  
pp. 216
Author(s):  
Prabu Aditya Sugianto ◽  
Mukhamad Adib Azka ◽  
Reynold Mahubessy ◽  
Paulus Agus Winarso
Keyword(s):  
Tropical Cyclone ◽  
Moisture Transport ◽  
Weather Forecast ◽  
Northern Region ◽  
Moderate Intensity ◽  
Tropical Storms ◽  
Atmospheric Conditions ◽  
Air Masses ◽  
Tropical Depression ◽  
Satellite Mapping

<p class="AbstractEnglish"><strong><span lang="EN-GB">Abstract:</span></strong><span lang="EN-GB"> </span><span lang="EN">Tropical cyclone are weather phenomena that hardly occur in Indonesia, but their effects can affect atmospheric conditions in the Indonesian region, especially in areas near its growth. One of the tropical cyclones that occurred near the territory of Indonesia is Kai-Tak tropical cyclone. Kai-Tak tropical cyclone occurred on December 13-22, 2017 in Philippine waters. In this study, atmospheric conditions in the Indonesian region will be examined during the Kaitak tropical cyclone. The data used in this study are ECMWF reanalysis model data (European Center for Medium Weather Forecast) in the form of vorticity data, Moisture Transport, and wind speed and direction, and also satellite data, namely Himawari-8 satellite IR-1 channel for viewing distribution. spatial cloud propagation index occurring as well as the Global Satellite Mapping of Precipitation (GSMaP) satellite to see the spatial distribution of rainfall as a result of Kai-Tak tropical cyclone. The results showed that in the period December 13-16 2017, in the northern part of Sulawesi, the eastern part of Kalimantan Island, the northern region of Sulawesi Island to the northern part of Halmahera Island and parts of Southern Sumatra and Java were indirectly affected by tropical storms Kai -not where Kai-Tak tropical storms cause light to moderate intensity rainfall in the region. Whereas in the period of 17-22 December 2017 where the weak tropical storms (tropical depression) rainfall that occurred in most parts of Indonesia occurred due to the spread of air masses from Asia.</span></p><p class="KeywordsEngish"><strong><span lang="EN-GB">Abstrak:</span></strong><span lang="EN-GB"> Badai tropis merupakan fenomena cuaca yang hampir tidak terjadi di Indonesia, tetapi dampaknya dapat mempengaruhi kondisi atmosfer di wilayah Indonesia khususnya di wilayah dekat pertumbuhannya. Salah satu badai tropis yang terjadi di dekat wilayah Indonesia yaitu badai tropis Kai-tak.  Badai tropis Kai-tak terjadi pada periode 13-22 Desember 2017 di perairan Filipina. Pada penelitian ini akan dikaji kondisi atmosfer di wilayah Indonesia pada saat  terjadinya badai tropis Kaitak. Data yang digunakan dalam penelitian ini yaitu data model <em>reanalysis </em>ECMWF (European Centre for Medium Weather Forecast) berupa data vortisitas,<em>Moisture Transport</em>, serta arah dan kecepatan angin, Selain itu digunakan juga data satelit yaitu satelit Himawari-8 kanal IR-1 untuk melihat distribusi spasial indeks konvektif sebaran awan yang terjadi serta satelit  <em>Global Satellite Mapping of Precipitation</em> (GSMaP) untuk melihat distribusi spasial curah hujan sebagai dampak dari badai tropis Kai-tak. Hasil penelitian menunjukkan bahwa pada periode 13-16 Desember 2017 , di wilayah Sulawesi bagian utara,wilayah Pulau Kalimantan bagian timur,wilayah utara Pulau Sulawesi hingga wilayah utara Pulau Halmahera serta sebagian Sumatera bagian Selatan dan Pulau Jawa terkena dampak secara tidak langsung dari badai tropis Kai-tak dimana badai tropis Kai-tak mengakibatkan hujan dengan intensitas ringan hingga sedang di wilayah tersebut.  Sedangkan pada periode 17-22 Desember 2017 dimana badai tropis melemah (tropical depression) curah hujan yang terjadi di sebagian besar wilayah Indonesia terjadi akibat adanya penjalaran massa udara dari Asia.</span></p>

scholarly journals A View of Tropical Cyclones from Above: The Tropical Cyclone Intensity Experiment

2017 ◽  
Vol 98 (10) ◽  
pp. 2113-2134 ◽  
Author(s):  
James D. Doyle ◽  
Jonathan R. Moskaitis ◽  
Joel W. Feldmeier ◽  
Ronald J. Ferek ◽  
Mark Beaubien ◽  
...  
Keyword(s):  
Tropical Cyclone ◽  
Lower Stratosphere ◽  
Inner Core ◽  
Horizontal Resolution ◽  
Intensity Change ◽  
Naval Research ◽  
Atmospheric Conditions ◽  
Tropical Cyclone Intensity ◽  
High Definition ◽  
Cyclone Intensity

Abstract Tropical cyclone (TC) outflow and its relationship to TC intensity change and structure were investigated in the Office of Naval Research Tropical Cyclone Intensity (TCI) field program during 2015 using dropsondes deployed from the innovative new High-Definition Sounding System (HDSS) and remotely sensed observations from the Hurricane Imaging Radiometer (HIRAD), both on board the NASA WB-57 that flew in the lower stratosphere. Three noteworthy hurricanes were intensively observed with unprecedented horizontal resolution: Joaquin in the Atlantic and Marty and Patricia in the eastern North Pacific. Nearly 800 dropsondes were deployed from the WB-57 flight level of ∼60,000 ft (∼18 km), recording atmospheric conditions from the lower stratosphere to the surface, while HIRAD measured the surface winds in a 50-km-wide swath with a horizontal resolution of 2 km. Dropsonde transects with 4–10-km spacing through the inner cores of Hurricanes Patricia, Joaquin, and Marty depict the large horizontal and vertical gradients in winds and thermodynamic properties. An innovative technique utilizing GPS positions of the HDSS reveals the vortex tilt in detail not possible before. In four TCI flights over Joaquin, systematic measurements of a major hurricane’s outflow layer were made at high spatial resolution for the first time. Dropsondes deployed at 4-km intervals as the WB-57 flew over the center of Hurricane Patricia reveal in unprecedented detail the inner-core structure and upper-tropospheric outflow associated with this historic hurricane. Analyses and numerical modeling studies are in progress to understand and predict the complex factors that influenced Joaquin’s and Patricia’s unusual intensity changes.

scholarly journals Storm Gloria: Sea State Evolution Based on in situ Measurements and Modeled Data and Its Impact on Extreme Values

2021 ◽  
Vol 8 ◽  
Author(s):  
Marta de Alfonso ◽  
Jue Lin-Ye ◽  
José M. García-Valdecasas ◽  
Susana Pérez-Rubio ◽  
M. Yolanda Luna ◽  
...  
Keyword(s):  
Extreme Values ◽  
Historical Context ◽  
Weather Forecast ◽  
Skill Score ◽  
Western Mediterranean ◽  
Special Focus ◽  
Atmospheric Conditions ◽  
Sea State ◽  
Wave Forecast

Storm Gloria, generated on January 17th, 2020 in the Eastern North Atlantic, crossed the Iberian Peninsula and impacted the Western Mediterranean during the following days. The event produced relevant damages on the coast and the infrastructures at the Catalan-Balearic Sea, due to extraordinary wind and wave fields, concomitant with anomalously intense rain and ocean currents. Puertos del Estado (the Spanish holding of harbors) has developed and operates a complex monitoring and forecasting system (PORTUS System), in collaboration with the Spanish Met Office (AEMET). The present work shows how Gloria was correctly forecasted by this system, alerts were properly issued (with special focus to the ports), and the buoys were able to monitor the sea state conditions during the event, measuring several new records of significant wave height and exceptional high mean wave periods. The paper describes, in detail, the dynamic evolution of the atmospheric conditions, and the sea state during the storm. It is by means of the study of both in situ and modeled PORTUS data, in combination with the AEMET weather forecast system results. The analysis also serves to place this storm in a historical context, showing the exceptional nature of the event, and to identify the specific reasons why its impact was particularly severe. The work also demonstrates the relevance of the PORTUS System to warn, in advance, the main Spanish Ports. It prevents accidents that could result in fatal casualties. To do so, the wave forecast warning performance is analyzed, making special focus on the skill score for the different horizons. Furthermore, it is demonstrated how a storm of this nature results in the need of changes on the extreme wave analysis for the area. It impacts all sorts of design activities at the coastline. The paper studies both how this storm fits into existing extreme analysis and how these should be modified in the light of this particular single event. This work is the first of a series of papers to be published on this issue. They analyze, in detail, other aspects of the event, including evolution of sea level and description of coastal damages.

scholarly journals DInSAR based land deformation detection in the karst landscape of Gunung Sewu

2020 ◽  
Vol 202 ◽  
pp. 04003
Author(s):  
Ridwan Arif Pambudi ◽  
Rijali Isnain Haripa
Keyword(s):  
Tropical Cyclone ◽  
Research Result ◽  
Northern Region ◽  
High Rate ◽  
Synthetic Aperture ◽  
Karst Landscape ◽  
Differential Interferometry ◽  
The Indian Ocean ◽  
Land Deformation ◽  
Preliminary Research

Hydrologic element specifically precipitation was fathomed to contribute in land deformation of karst landscape. Cempaka Tropical Cyclone (TC) had ensued in the last of 2017 in the Indian Ocean implicated to a high rate of rainfall upon the karst landscape of Gunung Sewu. This research aimed to identify the areas where sustained of land deformation due to the Cempaka TC. This research used a method of Differential Interferometry Synthetic Aperture Radar (DInSAR) by utilising a pair of Sentinel-1A satellite imageries to obtain the information of land deformation. The research result demonstrated the karst landscape of Gunung Sewu encountered land deformation after the Cempaka TC had impinged it. The land deformation occurred in the northern region of Gunung Sewu karst landscape in the forms of land uplifting with a range of 1 – 2 mm/year (115.36 km2) and gradually became a land subsidence with a range of -1 - -4 mm/year (989.25 km2) in the southern region of Gunung Sewu karst landscape. This finding was important as a preliminary research to mitigate the hazards and conserve the karst landscape of Gunung Sewu upon the threats of extreme weather in the future.

Improved Climatology of Tropical Cyclone Precipitation from Satellite Passive Microwave Measurements

2021 ◽  
pp. 1-42
Author(s):  
Song Yang ◽  
Vincent Lao ◽  
Richard Bankert ◽  
Timothy R. Whitcomb ◽  
Joshua Cossuth
Keyword(s):  
Tropical Cyclone ◽  
Wind Shear ◽  
Vertical Wind Shear ◽  
Passive Microwave ◽  
Shear Direction ◽  
Tropical Depression ◽  
Contraction Process ◽  
Concentric Pattern ◽  
Microwave Sensors ◽  
Left Quadrant

AbstractAccurate precipitation climatology is presented for tropical depression (TD), tropical storm (TS), and tropical cyclone (TC) over oceans using the recently-released, consistent and high quality precipitation datasets from all passive microwave sensors covering 1998-2012 along with the Automated Rotational Center Hurricane Eye Retrieval (ARCHER)-based TC center positions. Impacts with respect to the direction of both TC movement and the 200-850 hPa wind shear on the spatial distributions of TC precipitation are analyzed. The TC eyewall contraction process during its intensification is noted by a decrease in the radius of maximum rainrate with an increase in TC intensity. For global TCs, the maximum rainrate with respect to the direction of TC movement is located in the down-motion quadrants for TD, TS, and Cat 1-3 TCs, and in a concentric pattern for Cat 4-5 TCs. A consistent maximum TC precipitation with respect to the direction of the 200-850 hPa wind shear is shown in the down shear left quadrant (DSLQ). With respect to direction of TC movement, spatial patterns of TC precipitation vary with basins and show different features for weak and strong storms. The maximum rainrate is always located in DSLQ for all TC categories and basins, except the Southern Hemisphere basin where it is in the down shear right quadrant (DSRQ). This study not only confirms previously published results on TC precipitation distributions relative to vertical wind shear direction, but also provides a detailed distribution for each TC category and TS, while TD storms display an enhanced rainfall rate ahead of the down shear quadrants.

Near-future tropical cyclone predictions in the western North Pacific: fewer tropical storms but more typhoons

2019 ◽  
Vol 53 (3-4) ◽  
pp. 1341-1356 ◽  
Author(s):  
Woosuk Choi ◽  
Chang-Hoi Ho ◽  
Jinwon Kim ◽  
Johnny C. L. Chan
Keyword(s):  
Tropical Cyclone ◽  
North Pacific ◽  
Western North Pacific ◽  
Tropical Storms ◽  
Near Future

scholarly journals Aerodynamic and Thermal Problems Around and Inside a Dome and Telescope

1982 ◽  
Vol 67 ◽  
pp. 79-84
Author(s):  
Jean Rösch
Keyword(s):  
High Resolution ◽  
Light Beam ◽  
Parallel Plate ◽  
High Resolution Imaging ◽  
Atmospheric Conditions ◽  
Air Masses ◽  
Resolution Imaging ◽  
Large Telescopes

AbstractMuch effort has been spent at Pic-du-Midi, with increasingly large telescopes, to reduce the instrumental causes of image deterioration and take best advantage of local atmospheric conditions. With the new 2-meter reflector, specifically intended for high resolution imaging, the concept has been, ideally, to separate three air-masses: outside, inside the tube, and inside the dome. As a first step, no parallel plate of required size and quality being available, the tube is open to the outer air, but a connection between tube and dome aims at preventing the dome-air flowing across the light-beam. Results and expectations are presented.

scholarly journals On the Tropospheric Ozone Variations in a Coastal Area of Southwestern Europe under a Mesoscale Circulation

2010 ◽  
Vol 49 (4) ◽  
pp. 748-759 ◽  
Author(s):  
J. A. Adame ◽  
E. Serrano ◽  
J. P. Bolívar ◽  
B. A. de la Morena
Keyword(s):  
Solar Radiation ◽  
Coastal Area ◽  
Surface Ozone ◽  
Land Breeze ◽  
Industrial Complex ◽  
Atmospheric Conditions ◽  
Air Masses ◽  
Solar Radiation Intensity ◽  
Synoptic Forcing ◽  
The Mean

Abstract It is well established that surface ozone levels are greatly affected by orography, solar radiation intensity, meteorological conditions, and the levels of their precursors. In this work, the authors study the sea–land breeze circulation in its relation with the behavior of ozone in a coastal area, located in southwestern Europe, with high levels of solar radiation and an important industrial complex emitting air pollutants. Hourly mean data over a 7-yr period (1999–2005) have been used in the study. Two patterns of sea–land breeze have been identified after analyzing 2298 days of measurements: a “pure” breeze (179 cases) and another one, called a “nonpure” breeze (284 cases), which is the resulting flow of the former and northwesterlies synoptic forcing. Among other results, the highest levels of surface ozone were observed under pure sea–land breeze, with hourly values up to 100 μg m−3 in the mean daily evolution. In contrast, for a nonpure breeze, the 24-h average daily value was lower than the corresponding one under a pure breeze by a factor of 1.16 and could reach 1.60 in representative real cases. These findings give evidence that the formation and accumulation of ozone are favored by the conditions under a pure sea–land breeze: that is, perpendicular wind directions toward the coastline, effective recirculation of air masses, and formation of ozone residual layers above the sea. Because these atmospheric conditions occur in other coastal regions in the world, the conclusions of this study could be extended to them.

scholarly journals Impact of environmental moisture on tropical cyclone intensification

2015 ◽  
Vol 15 (24) ◽  
pp. 14041-14053 ◽  
Author(s):  
L. Wu ◽  
H. Su ◽  
R. G. Fovell ◽  
T. J. Dunkerton ◽  
Z. Wang ◽  
...  
Keyword(s):  
Tropical Cyclone ◽  
Moisture Transport ◽  
Inner Core ◽  
Wrf Model ◽  
Weather Research And Forecasting ◽  
Convective Activity ◽  
Dry Air ◽  
Moving Storm ◽  
Lagrangian Boundary ◽  
Moisture Increase

Abstract. The impacts of environmental moisture on the intensification of a tropical cyclone (TC) are investigated in the Weather Research and Forecasting (WRF) model, with a focus on the azimuthal asymmetry of the moisture impacts relative to the storm path. A series of sensitivity experiments with varying moisture perturbations in the environment are conducted and the Marsupial Paradigm framework is employed to understand the different moisture impacts. We find that modification of environmental moisture has insignificant impacts on the storm in this case unless it leads to convective activity that deforms the quasi-Lagrangian boundary of the storm and changes the moisture transport into the storm. By facilitating convection and precipitation outside the storm, enhanced environmental moisture ahead of the northwestward-moving storm induces a dry air intrusion to the inner core and limits TC intensification. In contrast, increased moisture in the rear quadrants favors intensification by providing more moisture to the inner core and promoting storm symmetry, with primary contributions coming from moisture increase in the boundary layer. The different impacts of environmental moisture on TC intensification are governed by the relative locations of moisture perturbations and their interactions with the storm Lagrangian structure.

scholarly journals The Role of Near-Core Convective and Stratiform Heating/Cooling in Tropical Cyclone Structure and Intensity

2018 ◽  
Vol 75 (1) ◽  
pp. 297-326 ◽  
Author(s):  
Guanghua Chen ◽  
Chun-Chieh Wu ◽  
Yi-Hsuan Huang
Keyword(s):  
Tropical Cyclone ◽  
Inner Core ◽  
Core Region ◽  
Intensity Change ◽  
Moderate Intensity ◽  
Convective Heating ◽  
Core Size ◽  
Heating And Cooling ◽  
Diabatic Processes ◽  
Spiral Rainbands

The effects of convective and stratiform diabatic processes in the near-core region on tropical cyclone (TC) structure and intensity change are examined by artificially modifying the convective and stratiform heating/cooling between 40- and 80-km radii. Sensitivity experiments show that the absence of convective heating in the annulus can weaken TC intensity and decrease the inner-core size. The increased convective heating generates a thick and polygonal eyewall, while the storm intensifies more gently than that in the control run. The removal of stratiform heating can slow down TC intensification with a moderate intensity, whereas the doubling of stratiform heating has little effect on the TC evolution compared to the control run. The halved stratiform cooling facilitates TC rapid intensification and a compact inner-core structure with the spiral rainbands largely suppressed. With the stratiform cooling doubled, the storm terminates intensification and eventually develops a double-eyewall-like structure accompanied by the significantly outward expansion of the inner-core size. The removal of both stratiform heating and cooling generates the strongest storm with the structure and intensity similar to those in the experiment with stratiform cooling halved. When both stratiform heating and cooling are doubled, the storm first decays rapidly, followed by the vertical connection of the updrafts at mid- to upper levels in the near-core region and at lower levels in the collapsed eyewall, which reinvigorates the eyewall convection but with a large outward slope.

scholarly journals Analisis Kondisi Atmosfer Terkait Siklon Tropis Pabuk Serta Pengaruhnya Terhadap Tinggi Gelombang di Perairan Kepulauan Riau

2020 ◽  
Vol 8 (2) ◽  
pp. 111
Author(s):  
Diana Cahaya Siregar ◽  
Vivi Putrima Ardah ◽  
Arlin Martha Navitri
Keyword(s):  
Tropical Cyclone ◽  
Satellite Imagery ◽  
Vertical Velocity ◽  
Atmospheric Condition ◽  
Weather Forecast ◽  
Distribution Data ◽  
Medium Range Weather Forecast ◽  
Wavewatch Iii ◽  
Medium Range ◽  
The Impact

Abstract Tropical cyclones is a synoptic scale low pressure system which can have an impact, both directly or indirectly to its traversed area. On January 1 to 6, 2019, Pabuk tropical cyclone was active on the South China Sea which its movement was to the west with its maximum wind speed was 64 knots. The aim of this study was to know the impact of Pabuk tropical cyclone to the atmospheric condition and sea wave on the Riau Islands region. This study used convective index analysis using IR1 channel of Himawari-8 satellite imagery and rainfall distribution data from rainfall observation by meteorological stations which are in the Riau Islands region. European Center for Medium-Range Weather Forecast (ECMWF) reanalysis data likes relative humidity, vertical velocity, and divergence was used to describe the atmospheric condition during the life time of Pabuk tropical cyclone. Wavewatch-III data was used to describe the condition of sea waves on the Riau Islands region. The results showed that Pabuk tropical cyclone had an impact on the growth of convective clouds which it caused the light to moderate rainfall quite evenly in the Riau Islands region. Besides, it was impact to the potential of high waves reached 4.5 meters on the northern of Anambas Sea and 7.0 meters on the north-eastern of Natuna Sea.Key words: Tropical cyclone, satellite imagery, wave height Abstrak Siklon tropis merupakan sistem tekanan rendah berskala sinoptik yang berdampak secara langsung maupun tidak langsung terhadap wilayah yang dilalui. Pada tanggal 1-6 Januari 2019, siklon tropis Pabuk muncul di wilayah Laut Cina Selatan dengan pergerakan ke arah barat dan kecepatan angin maksimumnya mencapai 64 knots. Penelitian ini dilakukan untuk mengkaji dampak yang ditimbulkan oleh siklon tropis Pabuk terhadap kondisi atmosfer dan gelombang laut di wilayah Kepulauan Riau. Penelitian ini menggunakan analisis indeks konvektif dari data citra satelit Himawari-8 kanal IR1 dan analisis sebaran hujan menggunakan data pengamatan curah hujan dari beberapa stasiun meteorologi yang ada di Kepulauan Riau. Data reanalisis European Centre for Medium-Range Weather Forecast (ECMWF) berupa kelembaban udara, vertical velocity, dan divergensi diolah untuk menggambarkan kondisi atmosfer pada masa hidup siklon tropis Pabuk. Data gelombang Wavewatch-III digunakan untuk menggambarkan kondisi gelombang laut di sekitar wilayah Kepulauan Riau. Hasil penelitian menunjukkan bahwa aktifnya siklon tropis Pabuk berdampak terhadap pertumbuhan awan konvektif yang menimbulkan hujan ringan hingga sedang yang cukup merata di wilayah Kepulauan Riau. Selain itu, berdampak juga pada potensi terjadinya gelombang tinggi mencapai 4,5 meter di sebelah utara Perairan Anambas dan 7,0 meter di sebelah timur laut Perairan Natuna.Kata Kunci: Siklon tropis, citra satelit, tinggi gelombang

Sign in / Sign up

Export Citation Format

Share Document