DOCSLIB.ORG

NOTES and CORRESPONDENCE Sensitivity to Horizontal Resolution of the Simulated Intensifying Rate and Inner-Core Structure of Typhoon Ida, an Extremely Intense Typhoon

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

JanuaryJournal of2016 the Meteorological Society of JapanS., Vol. KANADA 94A, pp. and 181−190, A. WADA 2016 181 DOI:10.2151/jmsj.2015-037 NOTES AND CORRESPONDENCE Sensitivity to Horizontal Resolution of the Simulated Intensifying Rate and Inner-Core Structure of Typhoon Ida, an Extremely Intense Typhoon Sachie KANADA Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya, Japan and Akiyoshi WADA Meteorological Research Institute, Japan Meteorological Agency, Tsukuba, Japan (Manuscript received 13 November 2014, in final form 16 June 2015) Abstract The model-resolution sensitivity of simulated intensifying and deepening rates of an extremely intense trop- ical cyclone (TC), Typhoon Ida (1958), was investigated using the Japan Meteorological Agency/Meteorological Research Institute nonhydrostatic atmospheric model with horizontal resolutions of 20, 10, 5, and 2 km. The results revealed great differences in the intensifying and deepening rates and their associated structural changes among simulations. The typhoon simulated by a finer horizontal resolution resulted in a greater maximum intensity associated with more rapid intensification. The differences were also revealed in the hourly precipitation pattern, the radius of maximum wind speed at 2-km altitude (RMW) and its shrinking behavior, near-surface inflow, and the axisymmetrization of the inner core. Only the cloud-resolving 2-km model, with explicit microphysics, could reproduce the observed maximum intensity and extreme intensification rate of the typhoon realistically because the model could produce the deep, intense, and upright updrafts inside RMW around the vorticity-rich area over the strong near-surface inflow. The results suggest that the appropriate horizontal resolution of the model should be used in dynamical downscaling experiments to examine extremely intense TCs with extremely high intensifying rates. Keywords typhoon; typhoon intensity; numerical simulation; nonhydrostatic model western Pacific oceans (e.g., Hurricane Katrina and 1. Introduction Hurricane Wilma in 2005; Typhoon Haiyan in 2013; A considerable number of category 4 and 5 trop- Typhoon Vongfong in 2014). According to Kaplan ical cyclones (TCs), on the Saffir–Simpson Hurri- and DeMaria (2003), most such high-intensity TCs cane Scale (http://www.nhc.noaa.gov/aboutsshws. are characterized by rapid intensification (RI). Thus, php), occur in both the North Atlantic and the North- more accurately predicting intensity changes of TCs, particularly RI, is a key factor for accurate TC inten- Corresponding author: Sachie Kanada, Hydrospheric sity forecasts and projections. Atmospheric Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan Although some recent studies have indicated that E-mail: [email protected] environmental parameters are skillful predictors of ©2015, Meteorological Society of Japan Atlantic TCs (e.g., Kaplan et al. 2010), other studies 182 Journal of the Meteorological Society of Japan Vol. 94A have suggested that the intensifying rate of a TC is zontal resolution with each of the following: 20 km only weakly dependent on environmental conditions (NHM20), 10 km (NHM10), 5 km (NHM5), and 2 (e.g., Hendricks et al. 2010). Furthermore, many km. The NHM20, NHM10, and NHM5 simulations observational and numerical studies have shown that used spectral nudging (SN; Nakano et al. 2012), the RI processes are closely related to the inner-core Kain–Fritsch cumulus parameterization scheme (KF; structure and convective activity of TC (e.g., Kieper Kain and Fritsch 1993), and the Level 3 Mellor– and Jiang 2012; Rogers et al. 2013; Wang and Wang Yamada–Nakanishi–Niino closure turbulence scheme 2014). The phenomena that have been proposed (Nakanishi and Niino 2004). In this study, moreover, to link convection with RI include vortical hot a 5-km-mesh atmospheric nonhydrostatic model with towers (Montgomery et al. 2006), convective asym- explicit microphysics and without the KF scheme metry (Braun et al. 2006), axisymmetrization of the (NoKF5) was used to study the impact of the cumulus inner-core triggered by deep convection (Guimond parameterization scheme. The SN method developed et al. 2010), and an upper-level warm core (Chen and for the downscaling experiments (Nakano et al., 2012) Zhang 2013). was applied above a height of 7 km for large-scale Simulations of convection associated with TCs wave components (wavelength > 1000 km) to reduce are strongly influenced by the horizontal resolution the track error of typhoons. Using NHM5, Nakano of the model used. Previous studies have suggested et al. (2012) conducted the sensitivity experiments that an atmospheric model with a horizontal reso- for 17 typhoons and showed that the central pressure lution of a few kilometers is necessary to reproduce (CP) of typhoons using the SN method was almost the inner-core structure and associated convection of comparable to that of those without using the SN TC (e.g., Braun and Tao 2000; Gentry and Lackmann method. The Louis scheme was used as the surface 2010). In addition, the downscaling experiments using boundary layer scheme (Louis et al. 1982), with a a 2-km-mesh atmospheric nonhydrostatic model surface–roughness–length formulation based on (NHM2) for the six most intense TCs in the climate Kondo (1975). The computational domain was 5400 run by a 20-km-mesh atmospheric general circula- km × 4600 km (Fig. 1). The number of vertical levels tion model (AGCM20) showed significant differ- was set to 55 (the top height was approximately 27 ences in the intensifying rate and the locations of the km). NHM20, NHM10, and NHM5 used a time step minimum central pressure (MCP) for simulated TCs of 40, 30, and 15 s, respectively. Other fundamental in AGCM20 and NHM2 (Kanada et al. 2013). These configurations were the same as those used by Kanada results raise the following question: How does the et al. (2012, 2013). Initial and lateral atmospheric horizontal resolution of a simulation affect the inten- boundary conditions (horizontal resolution, 1.25°) sity and intensifying rate of a simulated extremely and initial sea surface temperature (SST) conditions intense TC? (horizontal resolution, 0.56°) were provided every 6 In this study, we investigated the impact of model h from the JMA 55-year Reanalysis dataset (hereafter, resolution on not only TC intensity but also the JRA-55). Wind-profile retrieval data surrounding TCs TC intensifying rate by carrying out simulations of were assimilated in JRA-55 with the same prescribed Typhoon Ida (1958), one of the most intense typhoons observational errors as those used for TC bogus data with the greatest rapid deepening recorded since 1951. in JMA’s operational system. (See Ebita et al. 2011 for We paid special attention to differences in the convec- a detailed description). tive activity and inner-core structure among TCs In NHM2 simulations, initial and lateral boundary simulated at horizontal resolutions of 20, 10, 5, and conditions were provided every 6 h by the NHM5 2 km to improve the knowledge for the downscaling simulation. NHM2 applied the Deardorff–Black- experiments of an intense TC in both TC forecasts and adar scheme (Deardorff 1980; Blackadar 1962) and projections. bulk-type cloud microphysics with an ice phase that included ice, snow, and graupel (Murakami 1990) 2. Model and methods but did not apply the SN method or the cumulus 2.1 Model and experimental design parameterization scheme. The computational domain We used a non-hydrostatic atmospheric model of NHM2 was 3980 km × 2380 km (Fig. 1), and based on the Japan Meteorological Association the time step was 8 s. Otherwise, the configura- (JMA) operational non-hydrostatic mesoscale tion of NHM2 was the same as that of NHM20, model (JMANHM; Saito et al. 2007) and conducted NHM10, and NHM5. Numerical simulations with four sensitivity experiments using a different hori- NHM20, NHM10, and NHM5 nested in JRA55 were January 2016 S. KANADA and A. WADA 183 150˚ 160˚ 170˚ PreERI ERI 110˚ 120˚ 130˚ 140˚ a) 40˚ 30˚ 26 25 20˚ 24 23 21 10˚ 22 150 160˚ ˚ 120˚ 130˚ 140˚ Fig. 1. L(a) Map of the simulation domain used for the NHM20, NHM10, and NHM5 simulations, with the NHM2 simulation domain shown by the red rectangle. The circles show the tracks at 6-h intervals, and the stars show the location where the minimum central pressure (MCP) was reached, in the NHM20 (purple), NHM10 (green), NHM5 (blue), and NHM2 (red) simulations. The black symbols show the best-track data and MCP location of Typhoon Ida, and the numbers indicate the day of the month in September 1958. Temporal variations of (b) central pressure (CP; hPa), (c) the CP drop rate (dCP; hPa 6 h–1), (d) maximum wind speed (MWS; m s–1), and (e) MWS radius (RMW; km) at an altitude of 2 km in the NHM20 (purple), NHM10 (green), NHM5 (blue), and NHM2 (red) simulations. Best-track (black circles) and JRA-55 (open circles) data are also shown in panels (b) and (c). RI, rapid intensification; ERI, extremely rapid intensification. performed starting at 0000 UTC on September 21, maximum azimuthally mean Vt at an altitude of 2 km 1958. Then, using the NHM5 results, NHM2 numer- (hereafter, RMW): r* = r/RMW, where the normal- ical simulation was conducted from 0000 UTC on ized radius r* = 1 indicates the location of RMW. September 22, 1958. 3. Results 2.2 Analytical methods 3.1 General characteristics The storm center was determined as the approx- First, we give a brief overview of Ida. On imate geometric center (centroid) of the sea-level September 20, 1958, a tropical depression formed pressure (SLP) field in each of the NHM20, NHM10, from an easterly wave around the Marshall Islands, NHM5, and NHM2 simulations, based on the meth- and it received the name Ida at 1800 UTC (Fig. 1). odology of Braun (2002). Radial and tangential wind The storm moved westward while maintaining CP of speeds (hereafter, Vr and Vt, respectively) relative 985 hPa (Fig.
Recommended publications
  • Hurricane Andrew in Florida: Dynamics of a Disaster ^

    Hurricane Andrew in Florida: Dynamics of a Disaster ^

    Hurricane Andrew in Florida: Dynamics of a Disaster ^ H. E. Willoughby and P. G. Black Hurricane Research Division, AOML/NOAA, Miami, Florida ABSTRACT Four meteorological factors aggravated the devastation when Hurricane Andrew struck South Florida: completed replacement of the original eyewall by an outer, concentric eyewall while Andrew was still at sea; storm translation so fast that the eye crossed the populated coastline before the influence of land could weaken it appreciably; extreme wind speed, 82 m s_1 winds measured by aircraft flying at 2.5 km; and formation of an intense, but nontornadic, convective vortex in the eyewall at the time of landfall. Although Andrew weakened for 12 h during the eyewall replacement, it contained vigorous convection and was reintensifying rapidly as it passed onshore. The Gulf Stream just offshore was warm enough to support a sea level pressure 20-30 hPa lower than the 922 hPa attained, but Andrew hit land before it could reach this potential. The difficult-to-predict mesoscale and vortex-scale phenomena determined the course of events on that windy morning, not a long-term trend toward worse hurricanes. 1. Introduction might have been a harbinger of more devastating hur- ricanes on a warmer globe (e.g., Fisher 1994). Here When Hurricane Andrew smashed into South we interpret Andrew's progress to show that the ori- Florida on 24 August 1992, it was the third most in- gins of the disaster were too complicated to be ex- tense hurricane to cross the United States coastline in plained by thermodynamics alone. the 125-year quantitative climatology.
  • Effects of Horizontal Resolution and Air–Sea Flux Parameterization

    Effects of Horizontal Resolution and Air–Sea Flux Parameterization

    Effects of Horizontal Resolution and Air–Sea Flux Parameterization 已刪除: Impacts on the Intensity and Structure of simulated Typhoon Haiyan (2013) Mien-Tze Kueh1, Wen-Mei Chen1, Yang-Fan Sheng1, Simon C. Lin2, Tso-Ren Wu3, Eric Yen4, Yu-Lin Tsai3, Chuan-Yao Lin1 5 1Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan 2Academia Sinica Grid Computing Centre, Institute of Physics, Academia Sinica, Taipei, Taiwan 3Institute of Hydrological and Oceanic Sciences, National Central University, Taiwan 4Academia Sinica Grid Computing Centre, Academia Sinica, Taipei, Taiwan 10 Correspondence to: Chuan-Yao Lin ([email protected]) Abstract. This study investigates the effects of horizontal resolution and surface flux formulas on typhoon intensity and 已刪除: impacts structure simulations through the case study of Super Typhoon Haiyan (2013). Three sets of surface flux formulas in the 已刪除: the 15 Weather Research and Forecasting Model were tested using grid spacings of 1, 3, and 6 km. Increased resolution and more 35 已刪除: different 已刪除: Both i reasonable surface flux formulas can both improve typhoon intensity simulation, but their effects on storm structures differ. A combination of a decrease in momentum transfer coefficient and an increase in enthalpy transfer coefficients has greater potential to yield a stronger storm. This positive effect of more reasonable surface flux formulas can be efficiently enhanced when the grid spacing is appropriately reduced to yield an intense and contracted eyewall structure. As the resolution increases, 20 the eyewall becomes more upright and contracts inward. The size of updraft cores in the eyewall shrinks, and the region of 已刪除: ed downdraft increases; both updraft and downdraft become more intense.
  • Zhuhai Is Charging Its Own Residents for Covid-19 Tests but Footing the Bill

    Zhuhai Is Charging Its Own Residents for Covid-19 Tests but Footing the Bill

    FOUNDER & PUBLISHER Kowie Geldenhuys EDITOR-IN-CHIEF Paulo Coutinho www.macaudailytimes.com.mo FRIDAY T. 26º/ 31º Air Quality Good MOP 8.00 3534 “ THE TIMES THEY ARE A-CHANGIN’ ” N.º 15 May 2020 HKD 10.00 THE EDUCATION AND YOUTH AFFAIRS HEALTH AUTHORITY HINTS CASINO OPERATORS GALAXY AND BUREAU LEARNED OF THE MOST RECENT MELCO REPORTED STEEP DECLINES IN CASE OF TEACHER DISMISSAL ONLY COVID-19 IS HERE TO STAY FIRST QUARTER REVENUE CAUSED BY THE FROM A COURT DECISION IN THE LONG-TERM ONSET OF THE NOVEL CORONAVIRUS P2 P2 P4 AP PHOTO WHO An official said DOUBLE STANDARDS the debate between protecting health and Zhuhai is charging its own residents for Covid-19 tests but footing reviving economies is a “false dichotomy” and P3 that countries must the bill for Macau ID holders on the mainland. Why? remain vigilant as they lift restrictions. Takeshi Kasai, WHO’s Western Pacific director, said the reopening of economies shouldn’t be rushed and must be done cautiously. He said the world must “create a new normal in which we don’t have to choose between health and livelihood.” WHO also said yesterday that “this virus may never go away.” More on p6-7 Australia says it will continue to push for an inquiry into the origins of the coronavirus even if it hurts trade relations with China. Prime Minister Scott Morrison had been accused of playing “deputy sheriff” to the United States after calling for the inquiry. But he brushed off the criticism. “We have always been independent, we have always pursued our national interests, and we always will,” he told reporters.
  • 20 YEARS of GRATITUDE: Home for the Holidays

    20 YEARS of GRATITUDE: Home for the Holidays

    ShelterBox Update December 2020 20 YEARS OF GRATITUDE: Home for the Holidays As the calendar year comes to a close and we reach the half-way point of the Rotary year, families all over the world are gathering in new ways to find gratefulness in being together, however that may look. Thank to our supporters in 2020, ShelterBox has been able to ensure that over 25,000 families have a home for the holidays. Home is the center of all that we do at ShelterBox, the same way as home is central to our lives, families, and communities. “For Filipinos, home – or ‘bahay’ as we call it – really is where the heart is. It’s the centre of our family life, our social life and very often our working life too. At Christmas especially, being able to get together in our own homes means everything to us.” – Rose Placencia, ShelterBox Operations Philippines The pandemic did not stop natural disasters from affecting the Philippines this year. Most recently a series of typhoons, including Typhoon Goni, the most powerful storm since 2013’s Typhoon Haiyan, devastated many communities in the region. In 2020, before Typhoon Goni struck, ShelterBox had responded twice to the Philippines, in response to the Taal Volcano eruption and Typhoon Vongfong. As we deploy in response to this new wave of tropical storm destruction, Alejandro and his family are just one of many recovering from Typhoon Vongfong who now have a home for the holidays. Typhoon Vongfong (known locally as Ambo) devastated communities across Eastern Samar in the Philippines earlier this year.
  • Initializing the WRF Model with Tropical Cyclone Real-Time Reports Using the Ensemble

    Initializing the WRF Model with Tropical Cyclone Real-Time Reports Using the Ensemble

    Initializing the WRF Model with Tropical Cyclone Real-Time Reports using the Ensemble Kalman Filter Algorithm Tien Duc Du(1), Thanh Ngo-Duc(2), and Chanh Kieu(3)* (1)National Center for Hydro-Meteorological Forecasting, 8 Phao Dai Lang, Hanoi, Vietnam 1 (2)Department of Space and Aeronautics, University of Science and Technology of Hanoi, Vietnam 2 (3)Department of Earth and Atmospheric Sciences, Indiana University, Bloomington IN 47405, USA Revised: 18 April 2017 Submitted to Pure and Applied Geophysical Science Abbreviated title: Tropical Cyclone Ensemble Forecast Keywords: Tropical cyclones, ensemble Kalman filter, the WRF model, tropical cyclone vital, ensemble forecasting ____________________ *Corresponding author: Chanh Kieu, Atmospheric Program, GY428A Geological Building, Department of Earth and Atmospheric Sciences, Indiana University, Bloomington, IN 47405. Tel: 812-856-5704. Email: [email protected]. 1 1 Abstract 2 This study presents an approach to assimilate tropical cyclone (TC) real-time reports and the 3 University of Wisconsin-Cooperative Institute for Meteorological Satellite Studies (CIMSS) 4 Atmospheric Motion Vectors (AMV) data into the Weather Research and Forecasting (WRF) model 5 for TC forecast applications. Unlike current methods in which TC real-time reports are used to either 6 generate a bogus vortex or spin-up a model initial vortex, the proposed approach ingests the TC real- 7 time reports through blending a dynamically consistent synthetic vortex structure with the CIMSS- 8 AMV data. The blended dataset is then assimilated into the WRF initial condition, using the local 9 ensemble transform Kalman filter (LETKF) algorithm. Retrospective experiments for a number of 10 TC cases in the north Western Pacific basin during 2013-2014 demonstrate that this approach could 11 effectively increase both the TC circulation and enhance the large-scale environment that the TCs are 12 embedded in.
  • Information Bulletin Philippines: Typhoon Ambo (Vongfong)

    Information Bulletin Philippines: Typhoon Ambo (Vongfong)

    Information bulletin Philippines: Typhoon Ambo (Vongfong) Glide n° TC-2020-000134-PHL Date of issue: 14 May 2020 Date of disaster Expected landfall on 14 May 2020 Point of contact: Leonardo Ebajo, PRC Disaster Management Services Operation start date: N/A Expected timeframe: N/A Category of disaster: N/A Host National Society: Philippine Red Cross (PRC) Number of people affected: 7.1 million exposed Number of people to be assisted: N/A N° of National Societies currently involved in the operation: N/A N° of other partner organizations involved in the operation: N/A This bulletin is being issued for information only and reflects the current situation and details available at this time. The Philippine Red Cross (PRC), with the support of the International Federation of Red Cross and Red Crescent Societies (IFRC) is not seeking funding or other assistance from donors for this operation at this time. However, this might change as the situation evolves, especially after the storm makes landfall. An imminent DREF activation is currently under consideration. <click here to view the map of the affected area, and click here for detailed contact information> The situation According to the Philippines Atmospheric Geophysical and Astronomical Services Administration (PAGASA) as of 04:00 hours local time on 14 May 2020, Typhoon Vongfong is approximately 230 kilometers east of the Catarman, Northern Samar, moving west at 15 kmph. On entering the Philippine Area of Responsibility (PAR), it has been locally named “Typhoon Ambo”. PAGASA reports that Typhoon Ambo has maximum sustained winds of 150 kmph near the center and gustiness of up to 185 kmph.
  • Hong Kong Observatory, 134A Nathan Road, Kowloon, Hong Kong

    Hong Kong Observatory, 134A Nathan Road, Kowloon, Hong Kong

    78 BAVI AUG : ,- HAISHEN JANGMI SEP AUG 6 KUJIRA MAYSAK SEP SEP HAGUPIT AUG DOLPHIN SEP /1 CHAN-HOM OCT TD.. MEKKHALA AUG TD.. AUG AUG ATSANI Hong Kong HIGOS NOV AUG DOLPHIN() 2012 SEP : 78 HAISHEN() 2010 NURI ,- /1 BAVI() 2008 SEP JUN JANGMI CHAN-HOM() 2014 NANGKA HIGOS(2007) VONGFONG AUG ()2005 OCT OCT AUG MAY HAGUPIT() 2004 + AUG SINLAKU AUG AUG TD.. JUL MEKKHALA VAMCO ()2006 6 NOV MAYSAK() 2009 AUG * + NANGKA() 2016 AUG TD.. KUJIRA() 2013 SAUDEL SINLAKU() 2003 OCT JUL 45 SEP NOUL OCT JUL GONI() 2019 SEP NURI(2002) ;< OCT JUN MOLAVE * OCT LINFA SAUDEL(2017) OCT 45 LINFA() 2015 OCT GONI OCT ;< NOV MOLAVE(2018) ETAU OCT NOV NOUL(2011) ETAU() 2021 SEP NOV VAMCO() 2022 ATSANI() 2020 NOV OCT KROVANH(2023) DEC KROVANH DEC VONGFONG(2001) MAY 二零二零年 熱帶氣旋 TROPICAL CYCLONES IN 2020 2 二零二一年七月出版 Published July 2021 香港天文台編製 香港九龍彌敦道134A Prepared by: Hong Kong Observatory, 134A Nathan Road, Kowloon, Hong Kong © 版權所有。未經香港天文台台長同意，不得翻印本刊物任何部分內容。 © Copyright reserved. No part of this publication may be reproduced without the permission of the Director of the Hong Kong Observatory. 知識產權公告 Intellectual Property Rights Notice All contents contained in this publication, 本刊物的所有內容，包括但不限於所有 including but not limited to all data, maps, 資料、地圖、文本、圖像、圖畫、圖片、 text, graphics, drawings, diagrams, 照片、影像，以及數據或其他資料的匯編 photographs, videos and compilation of data or other materials (the “Materials”) are (下稱「資料」)，均受知識產權保護。資 subject to the intellectual property rights 料的知識產權由香港特別行政區政府 which are either owned by the Government of (下稱「政府」)擁有，或經資料的知識產 the Hong Kong Special Administrative Region (the “Government”) or have been licensed to 權擁有人授予政府，為本刊物預期的所 the Government by the intellectual property 有目的而處理該等資料。任何人如欲使 rights’ owner(s) of the Materials to deal with 用資料用作非商業用途，均須遵守《香港 such Materials for all the purposes contemplated in this publication.
  • Air-Sea Interaction: Hurricane/Typhoon

    Air-Sea Interaction: Hurricane/Typhoon

    Air-sea interaction: Hurricane/Typhoon ATM2106 Typhoon Haiyan, November 2013 Typhoon Vongfong, October 2014 https://youtu.be/WjxZd7fPSVI Movie from https://svs.gsfc.nasa.gov/12772 Hurricane • An intense storm of tropical origin • Winds exceeding 64 knots (74 mph, 119 km/h) Typhoon Cyclone Hurricane Tropical cyclone Hurricane structure Northern hemisphere (relatively) dry air eyewall 18 km Moist air Hurricane tour North Northern hemisphere eyewall West East N W E S South Hurricane Katrina over the Gulf of Mexico on August 28, 2005 Wind Precipitation rate 148 km/h Hurricane Formation • Hurricanes form over tropical waters where • The winds are light • The humidity is high • The surface temperature is warm (>26.5 ℃) • A convergence of the air and a force for the spin • Usually between 5° and 20° where f≠0 Sea surface temperature Number of storms Hurricane Formation • Conditions that prohibit the hurricane formation • Sinking air: near 20°, the air is open sinking associated with the subtropical high. • Strong upper-level winds: strong wind shear tends to disrupt organized convection and disperses heat and moisture. Hurricane Development 1. Sensible heat flux and latent heat release 2. Warmer T aloft near the cluster of thunderstorms 3. Pressure gradient forcing outward 4. A drop of the surface pressure from the warming and diverging the air in the small surface area. 5. The air begins to spin counterclockwise in the northern hemisphere and moves to the center 6. As the area of the circulation decreases, the wind speed increases. Hurricane Development • Hurricanes need energy to develop • Energy sources • Sensible heat from the ocean Q = ⇢ c c u (SST T ) S air p S 10 − air • Latent heat from condensation Q = ⇢ L c u (q⇤(SST) q ) L air e L 10 − air Hurricane Development Q = ⇢ c c u (SST T ) S air p S 10 − air Q = ⇢ L c u (q⇤(SST) q ) L air e L 10 − air • The warmer the water, the greater the transfer of sensible and latent heat into the air above • Greater wind speed promotes higher sensible and latent heat flux from the ocean to the atmosphere.
  • Influence of the Vongfong 2014 Hurricane on the Ionosphere and Geomagnetic Field As Detected by Swarm Satellites: 2

    Influence of the Vongfong 2014 Hurricane on the Ionosphere and Geomagnetic Field As Detected by Swarm Satellites: 2

    Solar-Terrestrial Physics. 2019. Vol. 5. Iss. 4. P. 74–80. DOI: 10.12737/stp-54201910. © 2019 V.A. Martines-Bedenko, V.A. Pilipenko, V.I. Zakharov, V.A. Grushin. Published by INFRA-M Academic Publishing House Original Russian version: V.A. Martines-Bedenko, V.A. Pilipenko, V.I. Zakharov, V.A. Grushin, published in Solnechno-zemnaya fizika. 2019. Vol. 5. Iss. 4. P. 90–98. DOI: 10.12737/szf-54201910. © 2019 INFRA-M Academic Publishing House (Nauchno-Izdatelskii Tsentr INFRA-M) INFLUENCE OF THE VONGFONG 2014 HURRICANE ON THE IONOSPHERE AND GEOMAGNETIC FIELD AS DETECTED BY SWARM SATELLITES: 2. GEOMAGNETIC DISTURBANCES V.A. Martines-Bedenko V.I. Zakharov Institute of Physics of the Earth, Lomonosov Moscow State University, Moscow, Russia, [email protected] Moscow, Russia, [email protected] V.A. Pilipenko A.M. Obukhov Institute of Atmospheric Physics RAS, Institute of Physics of the Earth, Moscow, Russia, [email protected] Moscow, Russia, [email protected] V.A. Grushin Institute of Space Research, Institute of Space Research, Moscow, Russia, [email protected] Moscow, Russia, [email protected] Abstract. Strong meteorological disturbances in the quasi-periodic ionospheric structure with a atmosphere, accompanied by the generation of waves characteristic scale of ~70 km induced by the interaction and turbulence, can affect ionospheric plasma and of acoustic waves excited by the typhoon with the E geomagnetic field. To search for these effects, we have layer of the ionosphere. In one of the flights over the analyzed electromagnetic measurement data from low- typhoon, a burst of high-frequency noise (~0.3 Hz) was orbit Swarm satellites during flights over the typhoon observed, which can be associated with the excitation of Vongfong 2014.
  • FALL 2011 - Volume 58, Number 3 the Air Force Historical Foundation Founded on May 27, 1953 by Gen Carl A

    FALL 2011 - Volume 58, Number 3 the Air Force Historical Foundation Founded on May 27, 1953 by Gen Carl A

    FALL 2011 - Volume 58, Number 3 WWW.AFHISTORICALFOUNDATION.ORG The Air Force Historical Foundation Founded on May 27, 1953 by Gen Carl A. “Tooey” Spaatz MEMBERSHIP BENEFITS and other air power pioneers, the Air Force Historical All members receive our exciting and informative Foundation (AFHF) is a nonprofi t tax exempt organization. Air Power History Journal, either electronically or It is dedicated to the preservation, perpetuation and on paper, covering: all aspects of aerospace history appropriate publication of the history and traditions of American aviation, with emphasis on the U.S. Air Force, its • Chronicles the great campaigns and predecessor organizations, and the men and women whose the great leaders lives and dreams were devoted to fl ight. The Foundation • Eyewitness accounts and historical articles serves all components of the United States Air Force— Active, Reserve and Air National Guard. • In depth resources to museums and activities, to keep members connected to the latest and AFHF strives to make available to the public and greatest events. today’s government planners and decision makers information that is relevant and informative about Preserve the legacy, stay connected: all aspects of air and space power. By doing so, the • Membership helps preserve the legacy of current Foundation hopes to assure the nation profi ts from past and future US air force personnel. experiences as it helps keep the U.S. Air Force the most modern and effective military force in the world. • Provides reliable and accurate accounts of historical events. The Foundation’s four primary activities include a quarterly journal Air Power History, a book program, a • Establish connections between generations.
  • Current Details from the Joint Typhoon Warning Center Latest Satellite Picture

    Current Details from the Joint Typhoon Warning Center Latest Satellite Picture

    Current Details from the Joint Typhoon Warning Center COORDINATES: 12.2° north, 126.2° east LOCATION: 630 kilometers (390 miles) east-southeast of Manila, Philippines MOVEMENT: west at 15 kph (9 mph) WINDS: 175 kph (110 mph) with gusts to 210 kph (130 mph) RADIUS OF TROPICAL STORM-FORCE WINDS: 120 kilometers (75 miles) RADIUS OF HURRICANE-FORCE WINDS: 30 kilometers (20 miles) SAFFIR-SIMPSON SCALE RANKING*: Category 2 FORECAST LANDFALL LOCATION: Samar Island, Visayas, Philippines FORECAST LANDFALL TIMEFRAME: Thursday afternoon or evening local time Latest Satellite Picture Source: Colorado State University (RAMMB) Discussion Typhoon Vongfong, located approximately 630 kilometers (390 miles) east-southeast of Manila, Philippines, is currently tracking west at 15 kph (9 mph). Animated satellite imagery indicates that the intensification trend of Vongfong has stalled, as the eye feature has become more ragged and started to partially fill. The cyclone has continued to track nearly due westward, with the JTWC anticipating landfall on Eastern Samar Island (part of the Visayas Island group) within the next few hours. An upper level atmospheric feature located across the South China Sea is likely amplifying a ridge of high pressure located to the north a bit more than previously forecast. This has led to Vongfong tracking further westward. A recent high-resolution satellite scan showed that the southern portion of the storm’s center has started to degrade. Given some of these parameters, the JTWC has lowered the initial intensity to 175 kph (110 mph); 1-minute average sustained winds, or Category 2 on the Saffir-Simpson Hurricane Wind Scale. The typhoon is expected to gradually shift on a west to west-northwest track, and later northwest, during the next 24-36 hours.
  • Update of Regional Weather and Smoke Haze for November 2014

    Update of Regional Weather and Smoke Haze for November 2014

    UPDATE OF REGIONAL WEATHER AND SMOKE HAZE FOR NOVEMBER 2014 1. Review of Regional Weather Conditions in October 2014 1.1 The Southwest Monsoon season continued to prevail in the first half of October 2014 and gradually transitioned to the Inter-Monsoon season in the second half of the month. 1.2 Two typhoons and one tropical storm affected the north-western Pacific Ocean in October 2014, namely Typhoon Phanfone, Typhoon Vongfong and Tropical Storm Nuri. Typhoon Phanfone, developed in the last week of September 2014 and made landfall over Honshu, Japan on 04 October 2014 resulting in seven deaths and more than 62 injured. Shortly after Typhoon Phanfone made landfall, the wrath of Typhoon Vongfong swept across the islands of Kyushu and Honshu, Japan on 13 and 14 October 2014 respectively, bringing strong winds and heavy rainfall to islands. In addition, Typhoon Vongfong led to the cancellation of a few hundred flights to and from Japan. 1.3 The presence of the monsoon trough over the northern ASEAN region during the first fortnight of October 2014 enhanced convective activities there and brought more than 100% of normal rainfall to parts of the Philippines, Laos PDR, Thailand and Vietnam. 1.4 Generally wet conditions affected the southern ASEAN region during the month. Brief periods of drier weather condition were observed in parts of southern ASEAN region, in particular, in Java island, southern Kalimantan and southern Sumatra. Less than 75% of normal rainfall was received in southern parts of Kalimantan and Sumatra, Java Island and Sulawesi while more than 125% of normal rainfall was felt in northern Sumatra, Peninsular Malaysia and Sabah in East Malaysia.