A tail strike event of an aircraft due to terrain-induced wind shear at the Hong Kong International Airport
|
|
- Anabel Bradford
- 5 years ago
- Views:
Transcription
1 METEOROLOGICAL APPLICATIONS Meteorol. Appl. 21: (2014) Published online 14 March 2012 in Wiley Online Library (wileyonlinelibrary.com) DOI: /met.1303 A tail strike event of an aircraft due to terrain-induced wind shear at the Hong Kong International Airport P. W. Chan* Hong Kong Observatory, Kowloon, Hong Kong, China ABSTRACT: At about 0155 UTC, 22 February 2009, an aircraft departing from the south runway of the Hong Kong International Airport to the east experienced significant wind shear of headwind loss. This may contribute towards the tail strike of the aircraft. This paper documents the meteorological observations in this tail strike event. The case occurs in a background atmosphere with a stable boundary layer and fresh east to southeasterly winds near the surface. The surface anemometer readings do not indicate the occurrence of significant headwind drop over the south runway. The glide-path scan data of a Doppler Light Detection and Ranging (LIDAR) system over the runway corridor concerned also do not indicate significant changes of the headwind due to blind zone of the LIDAR and geometrical constraint. However, the wind data measured on board the aircraft show that the tail strike may be due to a wind change from headwind of 19 knots to a tailwind of 5 knots over the western and middle parts of the south runway when the aircraft was on rotation. The headwind drop appears to be due to a jet of more easterly component near the surface occurring over the western part of the south runway. This drop could be captured if the LIDAR s headwind profiles over different runway corridors could be combined, and the present case suggests that, for wind shear alerting purposes, it may be necessary to try out combinations of headwind profiles over different parts of the same runway. The possibility of forecasting the significant wind shear in this case is also studied using a numerical weather prediction (NWP) model. The model results show that it may not be possible to forecast the event by using the direct model output alone, but would need to consider both the simulated wind direction as well as the forecast gust near the surface. Here the gust is forecast based on a physical approach as applied to the NWP model output. KEY WORDS tail strike; windshear; LIDAR Received 24 October 2011; Revised 22 December 2011; Accepted 31 January Introduction The Hong Kong International Airport (HKIA) is situated in an area of complex terrain. To its south is the mountainous Lantau Island with peaks rising to about 1000 m above mean sea level and valleys as low as 400 m in between. The complex terrain may lead to airflow disturbances in the vicinity of the airport when the air climbs over the mountains. Terraindisrupted airflow is common when the boundary layer is stable in the background atmosphere, which often occurs in the spring time. The airflow disturbances over HKIA could be hazardous to the landing/departing aircraft by causing low-level wind shear, which refers to wind shear occurring within a height of 1600 feet (about 500 m) over the airport or within a distance of 3 nautical miles (about 5.6 km) from the runway end. In aviation meteorology, the wind shear is considered to be significant if it leads to headwind/tailwind change of 15 knots (7.7 m s 1 ) or more. Significant wind shear may cause the aircraft to deviate from its intended flight path by changing the lift, which could be hazardous to the operation of the aircraft when it is close to the ground, e.g. during rotation for departing aircraft. At HKIA, terrain-induced wind shear is the most common type of low-level wind shear experienced by the aircraft. Based * Correspondence to: P. W. Chan, Hong Kong Observatory, 134A Nathan Road, Kowloon, Hong Kong, China. pwchan@hko.gov.hk on the pilot reports, about 70% of the wind shear is due to terrain disruption of the airflow. The other causes of wind shear include sea breeze, microburst, gust front, low-level jets as well as building effects on the airflow. Terrain-induced wind shear could occur in the spring time, when the background easterly winds of continental origin flow over Lantau Island under a stable atmosphere, and it could also appear in the summer time, with the cross-mountain airflow brought about by intense summer monsoon or tropical cyclones. Though it is not common, there have been reports of tail strikes of the departing aircraft at HKIA due to terrain-induced wind shear. According to the records of an airline in Hong Kong, there were two such reports in the recent years. One such case occurring in March 2010 has been documented in Chan (2011). In the present paper, another case of tail strike of an aircraft due to terrain-induced wind shear occurring in February 2009 is described. The peculiarities of this event as compared to the event in March 2010 include: 1. while the cause of the tail strike in the present case again appears to be related to headwind loss occurring near the ground, this headwind loss was not recorded by the surface anemometers, contrary to the 2010 case, and, 2. contrary to the 2010 case, while the headwind profile measured by the Doppler Light Detection And Ranging (LIDAR) system over the runway corridor concerned does not give the headwind loss leading to the tail strike, it may be possible to combine the headwind profiles obtained over 2012 Royal Meteorological Society
2 Tail strike event of aircraft 505 different runway corridors in order to capture the headwind loss. This may suggest another approach in using the LIDAR data for alerting wind shear occurring at very low level close to the ground, which is not attempted with the present geometrical setup of the LIDAR Wind shear Alerting System (LIWAS) (Shun and Chan, 2008). Moreover, as in the 2010 case, the possibility of using a high resolution numerical weather prediction (NWP) model for forecasting the significant wind shear in the present case is considered in order to find out the possibility of providing an earlier alert to the aviation weather forecasters about the chance of occurrence of significant low-level wind shear. The approach of using an NWP model includes numerical simulation down to a horizontal resolution of 50 m so as to resolve the fine details of the terrain of Lantau Island, and the consideration of gust forecast using a physical method as described in Brasseur (2001). 2. Synoptic situation The tail strike event occurred at 0155 UTC (0955 HKT, which is 8 h ahead of UTC), 22 February The aircraft concerned departed from the south runway of HKIA to the east. The surface weather chart at 0000 UTC, 22 February 2009 is shown in Figure 1. There was a ridge of high pressure over the part of the southeastern coast of China closest to Hong Kong, bringing easterly winds to Hong Kong and the adjacent areas. The easterly winds were not particularly strong. In fact, over the south China coast there were only three isobars (with a pressure increment of 2 hpa between two isobars). This is a typical synoptic pattern of easterly winds with continental origin over Hong Kong in the spring time. Higher up in the boundary layer of the atmosphere, for instance at 925 and 850 hpa levels (not shown), south to southwesterly winds prevailed along the coastal area, and they had an origin from the more humid and warmer airmass over the South China Sea. The undercutting of the warmer southerlies by the cooler surface easterlies resulted in a stable boundary layer as well as the occurrence of low clouds and light rain patches. Close to the time of the event (0200 UTC, 22 February 2009), the weather observer at HKIA reported 6 oktas of clouds, with a cloud base height of 1000 feet (about 300 m). 3. Local meteorological observations The surface wind data around the time of the event (0155 UTC, 22 February 2009) are shown in Figure 2. Southeasterly winds basically prevailed over HKIA and the sea to the west. On the other hand, the winds had a more easterly component at the northeastern corner of the airport island as well as the sea to the east. Over the south runway, all four anemometers recorded south-southeasterly winds of knots ( m s 1 ). There was generally a decrease of wind speed from the western to the eastern end of the south runway, but the corresponding headwind change did not appear to be significant (i.e. far less than 15 knots, or 7.7 m s 1 ). The background wind profile in the lower atmosphere may be indicated by the measurements of the radar wind profiler at Cheung Chau (location in Figure 2). This wind profiler operates at a central frequency of 1299 MHz. It measures the three Figure 1. Surface isobaric chart at 0000 UTC, 22 February 2009.
3 506 P. W. Chan Figure 2. Observations from the surface weather stations at 0955 HKT, 22 February The green wind barbs give the wind observations. The value at the upper right corner of a station is the pressure in 0.1 hpa (after deducing 1000 hpa), that at the upper left corner is the temperature, and those at the lower left corner are the dew point and the sea surface temperature. Height contours are in 100 m. A full wind barb equates to 10 knots (5.1 m s 1 ) and a half wind barb equates to 5 knots (2.6 m s 1 ). The blue dots are the locations of the two LIDARs. components of the wind up to a height of 6000 m above ground by using three radar beams, namely, one to the vertical, and two oblique beams with an angle of about 15 from the vertical. Wind data are available every 60 m in the low mode (up to 1500 m above ground), and every 200 m in the high mode (up to 6000 m above ground). The wind profiles presented in this paper are obtained by combining the data from the two modes. The data are basically 10 min averages. The wind profile at the time of the event (0155 UTC, 22 February 2009) from the Cheung Chau wind profiler is given in Figure 3. In the lowest 600 m or so above mean sea level, wind speed increased slightly from 7 to 11 m s 1.The winds then weakened a bit aloft up to 1000 m, and increased again in the upper part of the boundary layer. For wind direction, it was veering steadily with height, from southeasterly near the surface becoming southwesterly at the top of the boundary layer. The cross-mountain airflow of south to southeasterly winds, together with a wind speed in the order of 10 m s 1 within the first few 100 m above ground, could be favourable to the occurrence of terrain-disrupted airflow downstream of Lantau Island, namely, in the region of HKIA. The background temperature profile is obtained by radiosonde ascent at King s Park, the radiosonde station in Hong Kong located at about 25 km to the east of HKIA. The radiosonde data are shown in Figure 4, including the temperature and the dew point profiles. It can be seen that the atmosphere was close to saturation above 200 m from the mean sea level, which is explained in the previous section as a result of the cutting of the warmer and more humid airflow with maritime origin by the cooler continental airflow near the surface. Moreover, this undercutting results in a temperature inversion of about 2 C between 200 and 300 m above mean sea level. Figure 3. Wind profile given by the wind profiler at Cheung Chau at 0155 UTC, 22 February 2009: wind speed (a) and wind direction (b). The wind data refer to 10 min averages. The height of this temperature inversion is well below the altitude of the peaks of Lantau Island. Combining with the results from the Cheung Chau wind profiler, it is noted that the
4 Tail strike event of aircraft 507 Figure 4. Temperature (blue) and dew point (pink) profile from the radiosonde ascent at King s Park at 0000 UTC, 22 February cross-mountain airflow in a stable atmosphere with the temperature inversion below the height of the mountains could be favourable for the occurrence of terrain-induced airflow disturbances over the airport. 4. LIDAR observations The Hong Kong Observatory (HKO) operates two LIDARs at HKIA, with one serving each of the two runways of the airport. The LIDAR uses an infrared laser beam with a wavelength of 2 μm for measuring the line-of-sight (or radial) velocity of the wind. There is a blind zone of about 400 m from the LIDAR, in which no data could be collected due to constraints of the optics of the system. The main application of the LIDAR is the alerting of low-level wind shear experienced by the aircraft, using an algorithm called LIWAS developed by HKO (details could be found in Shun and Chan, 2008). The locations of the LIDARs are shown in Figure 2. LIWAS alerts wind shear based on a special scanning pattern of the laser beam, called the glide-path scan. In this kind of scanning, the elevation and the azimuthal motors of the LIDAR s scanner rotate in unison to slide the laser beam along the glide path of the aircraft, which is taken to be a line with an elevation angle of 3 originating from the runway end for arriving aircraft and a line with an elevation angle of 6 originating from the middle of the runway for departing aircraft. The radial velocities so collected along a glide path are used to construct the headwind profile to be encountered by the aircraft, as long as the radial direction and the runway orientation are sufficiently close together. A threshold of 30 is adopted for the angle between the measurement radial and the runway direction, i.e. when the angle is less than 30, the radial velocity is used directly to represent the headwind in the direction of the glide path. The headwind profile obtained from the glide-path scan is the basis for wind shear detection and alerting. An algorithm has been developed by HKO to automatically look for abrupt changes of the headwind in this profile. Apart from the glide-path scan, the LIDARs also perform the more conventional scanning patterns such as Plan-position Indicator (PPI) scans to give an overview of the wind distribution over the airport area to support the work of the aviation weather forecasters. Since the tail strike event in the present study occurs over the south runway, the data from the south runway LIDAR are considered here. The 6 PPI scan of this LIDAR at the time of the event is given in Figure 5(a). The 6 PPI data are used because it is close to the 6 glide path of the departing aircraft. It could be seen that a southeasterly airstream with a speed of 14 m s 1 prevailed over the airport. There are some small-scale features of reverse flow, e.g. appearing as green dots over the eastern part of the south runway, each having a spatial scale of a couple of 100 m, against the background away-from-the-lidar flow (in brown and yellow). However, such features are small in both magnitude and scale compared to the change in headwind apparent in the aircraft data (see Figure 6, to be discussed below). The headwind profile obtained by the south runway LIDAR for the runway corridor concerned, 07RD corridor (departing from the south runway to the east), is shown in Figure 6(a). It is compared with the headwind measured onboard the aircraft that experienced the tail strike. The corresponding heights of the laser beam and the aircraft are shown in Figure 6(b). It could be seen that the two headwind profiles are generally consistent with each other for the distance of 1 nautical mile from the runway end (i.e. 1 nautical mile to the west of the eastern end of the south runway) and further to the east. Over
5 508 P. W. Chan Figure 6. Headwind profile (a) from the aircraft that experienced tail strike, the south runway LIDAR, and the model simulation; the altitudes of the aircraft, LIDAR scan and model data extraction are given in (b). Imperial units are used because they are more commonly adopted in aviation meteorology. They correspond to metric units as follows: 1 knot = m s 1, 1 nautical mile = km, and 1 feet = m. The data are taken at 0155 UTC, 22 February Figure 5. Radial velocity image from the south runway LIDAR as measured in 6 conical scan (a) and 3.2 conical scan (b) at 0155 UTC, 22 February that region, the headwind had minor fluctuations only, and there did not appear to have significant wind shear. It turns out that the significant wind shear that may lead to the tail strike appears at the distance of about 1.5 nautical miles to 1 nautical mile, namely, with a headwind drop of 19 knots (9.8 m s 1 )to 5 knots ( 2.6 m s 1 ) over a distance of 0.5 nautical mile (0.9 km). Due to the blind zone of the LIDAR and the geometrical constraint (i.e. the angle between the runway orientation and direction of the laser beam is more than 30 ), no headwind data are available from the 07RD glide-path scan itself. In order to supplement the headwind profile over 07RD, the headwind profile obtained over the western part of the south runway, 07RA runway corridor, is considered (07RA means arriving at the south runway from the west). The corresponding 3.2 PPI scan imagery of the south runway LIDAR (mainly used for monitoring the airflow to be encountered by the arriving aircraft) is shown in Figure 5(b). It could be seen that the low-level southeasterly jet over the western part of airport as shown in the 3.2 PPI scan had more easterly component than that shown in the 6 PPI scan. As a result, the corresponding 07RA glide-path scan data (Figure 6(a)) had rather large headwind value at a distance of 1.5 nautical miles, namely, about 18 knots (9.3 m s 1 ). The altitude of the laser beam in the 07RA glide-path scan is shown in Figure 6(b). If the glide-path scan data of 07RA and 07RD are combined, basically the shape of the headwind profile is very similar to that recorded onboard the aircraft (Figure 6(a)). Unfortunately, due to the blind zone of the LIDAR and geometrical constraint, the headwind data at the distance between 1.2 and 1 nautical miles from the eastern end of the south runway are not available. Nonetheless, the available headwind data obtained by glide-path scans show that there would be a significant drop of headwind over the western part of the south runway. The combination of headwind data from different glide-path scans is not made in the existing LIWAS algorithm. Based on the present case, it may be necessary to do such headwind profile combination in order to capture the significant wind shear that occurs at very low level near the ground.
6 Tail strike event of aircraft 509 Figure 7. The simulated wind magnitude at the surface at 0200 UTC, 22 February 2009 for the model domain with a spatial resolution of 200 m; the colour scale of the wind magnitude is given at the bottom of the figure. The simulated winds at the weather stations are given in wind barbs. The runways are indicated by the black straight lines. 5. Numerical simulation The possibility of forecasting the present case of significant wind shear is studied by using Regional Atmospheric Modelling System (RAMS) version 4.4. It is nested with the Operational Regional Spectral Model (ORSM) of HKO with a horizontal resolution of 20 km. Four nested runs of RAMS are performed, with a horizontal resolution of 4 km, 800, 200 and 50 m. High-resolution terrain data of Hong Kong are used in the model, with a horizontal resolution of 100 m. Details of RAMS could be found in Cotton et al. (2003). In the simulation, The Deardorff turbulence parameterization scheme (Deardorff, 1980) is employed. The simulated wind field at a height of 10 m above ground for the 200 m resolution domain is shown in Figure 7. It can be seen that the wind directions at the western and the middle parts of the south runway are very similar, southeasterly winds. However, the wind speed at the western part is slightly higher than that over the middle part. This slightly higher wind speed leads to a higher value of headwind. The model also simulates that the wind at the eastern part of the south runway has more easterly component. As a result, the headwind value over there is also higher. This pattern is basically maintained in the 50 m resolution run (Figure 8). As a result, the simulated headwind profile over the south runway takes on the shape as given in Figure 6(a), higher values of headwind at a distance of 1.5 nautical miles and 0.5 nautical miles from the eastern end of the south runway, and lower value at a distance of about 1 nautical mile. The corresponding altitudes of the model grid points taken to construct the headwind profile are shown in Figure 6(b), basically following the height of the aircraft concerned. It can be seen from Figures 7 and 8 that the model-simulated wind field near the surface has two major discrepancies as compared with actual observations (e.g. Figures 2 and 5). First, the region of east-southeasterly winds is more extensive over the airport island in the simulation results, as compared with the actual surface observations from the anemometers. The former cover the north runway and the eastern part of the south runway, while in reality the east-southeasterly winds only appear at the northeastern corner of HKIA. Second, there is an extensive area of cyclonic flow to the west of HKIA, but it is not present in the actual observations. The model may have over-reacted to the low level temperature inversion (Figure 4) in the simulation of the near-surface wind field. Despite the above discrepancies, the model basically reproduces the board features of the terrain-disrupted southeasterly airflow over the airport island. However, by using the direct model output only, the simulated headwind profile does not show the significant headwind change as experienced by the aircraft, Figure 6(a). Similar to Chan (2011), the authors would like to see the possibility of using the forecast gust as an indication of stronger headwind change. The physical modelling approach for gust as described in Brasseur (2001) is adopted. It is applied to the modelling results for the horizontal resolution of 200 m. The forecast gust near the surface is given in Figure 9. It could be seen that, probably due to airflow disruption by Nei Lak Shan, the gust could be higher over the western part of the south runway, reaching about 27 knots (14 m s 1 ). By using the simulated wind direction over that region, the simulated headwind could reach 21 knots (11 m s 1 ). Together with the simulated headwind minimum of about 1 knots (0.5 m s 1 )at a distance of about 1 nautical mile from the runway end, the headwind change (21 knots to 1 knots) becomes comparable with that from the actual aircraft data. Therefore, by considering the spatial distribution as well as the value of the simulated
7 510 P. W. Chan Figure 8. The simulated wind magnitude at the surface at 0200 UTC, 22 February 2009 for the innermost domain (spatial resolution of 50 m); the colour scale of the wind magnitude is given at the bottom of the figure. The simulated winds at the weather stations are given in wind barbs. The runways are indicated by the black straight lines. gust, it may be possible to give the aviation weather forecaster an earlier alert about the chance of occurrence of significant headwind drop over the western and the middle parts of the south runway. 6. Conclusion A tail strike event of an aircraft due to terrain-induced wind shear at HKIA on 22 February 2009 is presented in this paper. From the aircraft data, the tail strike could occur as a result of significant headwind drop from 19 knots to 5 knots over the western and the middle parts of the south runway during rotation. This significant wind shear is not captured by surface anemometer data as well as the LIDAR s headwind profile over 07RD runway corridor alone. However, by combining the LIDAR s headwind profiles over 07RA and 07RD, it is possible to recover this headwind loss. The higher headwind value at the western part of the south runway may be due to a more easterly component of the southeasterly jet in the lower part of the boundary layer, after the jet passes through the gaps of Lantau Island. Based on the present case, there appears to be a need to combine the headwind profiles from the LIDAR as obtained by glide-path scans over different runway corridors in order to capture the significant wind shear that occurs close to the ground. Combining the different LIDAR scans clearly shows that there is a drop of headwind component in excess of 15 knots (the threshold for a warning) although from these data alone it is not possible to say exactly where this drop occurs. However, due to the blind zone of the LIDAR as well as geometrical constraints, there are still many missing headwind data in the combined headwind profile. It may be necessary to fill in this data void by using, for instance, an additional LIDAR or surface anemometer readings. The possibility of forecasting this event of terrain-induced wind shear is studied by using RAMS with a horizontal resolution down to 50 m. The direct model output of the simulated headwind profile does not capture the headwind loss concerned. However, by considering the simulated surface wind field as well as the forecast gust, it may be possible to give the aviation weather forecasters an earlier indication about the chance of occurrence of significant wind shear near the ground. The present results as well as Chan (2011) serve to document the meteorological observations in the only two cases of tail strikes due to terrain-disrupted airflow over HKIA in the recent years, according to the record of an airline. The common
8 Tail strike event of aircraft 511 Figure 9. The simulated gust at the surface at 0200 UTC, 22 February 2009 for the model domain with a horizontal resolution of 200 m; the colour scale of the gust is given at the bottom of the figure. feature of both cases is the occurrence of significant headwind drop near the ground during the rotation of the aircraft. The major difference between the two events is the height of the occurrence of the significant wind shear: the case of Chan (2011) occurred very close to the ground so that the wind shear could be picked up from the ground-based anemometer measurements, whereas in the present case the wind shear may have occurred at higher location so that it could not be captured by the anemometer data but by the LIDAR data which scanned slightly higher above the runway. More cases of tail strike would be investigated in the future to see if there are any common features about the winds shared by these events. Tail strike is a hazardous condition as a danger to the aircraft and its passengers. Fortunately, in the two events documented so far, the aircraft involved could continue its flight (departing from HKIA). There does not appear to be an emerging trend in more frequent occurrence of terrain-induced wind shear leading to tail strike. References Brasseur O Development and application of a physical approach to estimating wind gusts. Mon. Weather Rev. 129: Chan PW An event of tail strike of an aircraft due to terrain-induced wind shear at the Hong Kong International Airport. Meteorol. Appl. DOI: /met.264. Cotton WR, Pielke RA Sr, Walko RL, Liston GE, Tremback C, Jiang H, McAnelly RL, Harrington JY, Nicholls ME, Carrio GG, McFadden JP RAMS 2001: current status and future directions. Meteorol. Atmos. Phys. 82: Deardorff JW Stratocumulus-capped mixed layers derived from a three-dimensional model. Boundary Layer Meteorol. 18: Shun CM, Chan PW Applications of an infrared Doppler Lidar in detection of wind shear. J. Atmos. Oceanic Technol. 25:
P1.17 Super-high-resolution Numerical Simulation of Atmospheric Turbulence in an Area of Complex Terrain
P1.17 Super-high-resolution Numerical Simulation of Atmospheric Turbulence in an Area of Complex Terrain P.W. Chan * Hong Kong Observatory, Hong Kong, China 1. INTRODUCTION Turbulent airflow occurs at
More informationP. W. Chan and K. K. Hon. 1. Introduction
Advances in Meteorology Volume 16, Article ID 1454513, 9 pages http://dx.doi.org/1.1155/16/1454513 Research Article Observation and Numerical Simulation of Terrain-Induced Windshear at the Hong Kong International
More informationRemote Sensing of Windshear under Tropical Cyclone Conditions in Hong Kong
Remote Sensing of Windshear under Tropical Cyclone Conditions in Hong Kong Dr H K Lam Director of the Hong Kong Observatory Permanent Representative of Hong Kong, China with WMO Vice-President of WMO Regional
More information8.7 Calculation of windshear hazard factor based on Doppler LIDAR data. P.W. Chan * Hong Kong Observatory, Hong Kong, China
8.7 Calculation of windshear hazard factor based on Doppler LIDAR data P.W. Chan * Hong Kong Observatory, Hong Kong, China Paul Robinson, Jason Prince Aerotech Research 1. INTRODUCTION In the alerting
More informationSUMMARY. information from
INTERNATIONAL CIVIL AVIATION ORGANIZATION WORLD METEOROLOGICAL ORGANIZATION MET/14-IP/ /16 2/6/14 English only Meteorology (MET) Divisional Meeting (2014) Commission for Aeronautical Meteorology Fifteenth
More informationJ1.2 Short-term wind forecasting at the Hong Kong International Airport by applying chaotic oscillatory-based neural network to LIDAR data
J1.2 Short-term wind forecasting at the Hong Kong International Airport by applying chaotic oscillatory-based neural network to LIDAR data K.M. Kwong Hong Kong Polytechnic University, Hong Kong, China
More informationApplication of microwave radiometer and wind profiler data in the estimation of wind gust associated with intense convective weather
Application of microwave radiometer and wind profiler data in the estimation of wind gust associated with intense convective weather P W Chan 1 and K H Wong 2 1 Hong Kong Observatory, 134A Nathan Road,
More informationCOMPARISON OF DOPPLER LIDAR OBSERVATIONS OF SEVERE TURBULENCE AND AIRCRAFT DATA. S.T. Chan * and C.W. Mok Hong Kong Observatory, Hong Kong
4.6 COMPARISON OF DOPPLER LIDAR OBSERVATIONS OF SEVERE TURBULENCE AND AIRCRAFT DATA S.T. Chan * and C.W. Mok Hong Kong Observatory, Hong Kong 1. INTRODUCTION The Hong Kong International Airport (HKIA)
More informationA HIGH-RESOLUTION RAPIDLY-UPDATED METEOROLOGICAL DATA ANALYSIS SYSTEM FOR AVIATION APPLICATIONS
A HIGH-RESOLUTION RAPIDLY-UPDATED METEOROLOGICAL DATA ANALYSIS SYSTEM FOR AVIATION APPLICATIONS C. S. Lau *, J. T. K. Wan and M. C. Chu Department of Physics, The Chinese University of Hong Kong, Hong
More informationPublished by the Hong Kong Observatory, Hong Kong Special Administrative Region Government.
Windshear and Turbulence in Hong Kong - information for pilots Published by the Hong Kong Observatory, Hong Kong Special Administrative Region Government. 1st edition 2002 2nd edition 2005 Copyright reserved
More informationThe first tropospheric wind profiler observations of a severe typhoon over a coastal area in South China
The first tropospheric wind profiler observations of a severe typhoon over a coastal area in South China Lei Li, 1 Pak Wai Chan, 2 Honglong Yang, 1 Rong Zong, 1 Xia Mao, 1 Yin Jiang 1 and Hongbo Zhuang
More informationWMO Aeronautical Meteorology Scientific Conference 2017
Session 1 Science underpinning meteorological observations, forecasts, advisories and warnings 1.3 Aerodrome throughput 1.3.1 Wake vortex detection and prediction Frequent-output sub-kilometric NWP models
More informationReprint 850. Within the Eye of Typhoon Nuri in Hong Kong in C.P. Wong & P.W. Chan
Reprint 850 Remote Sensing Observations of the Subsidence Zone Within the Eye of Typhoon Nuri in Hong Kong in 2008 C.P. Wong & P.W. Chan 8 th International Symposium on Tropospheric Profiling: Integration
More informationChan et al. / J Zhejiang Univ-Sci A (Appl Phys & Eng) (7):
Chan et al. / J Zhejiang Univ-Sci A (Appl Phys & Eng) 213 14(7):469-481 469 Journal of Zhejiang University-SCIENCE A (Applied Physics & Engineering) ISSN 1673-565X (Print); ISSN 1862-1775 (Online) www.zju.edu.cn/jzus;
More informationHong Kong Collection
(Disclaimer The Government of the Hong Kong Special Administrative Region (including its servants and agents) and the International Federation of Air Line Pilots' Associations make no warranty, statement
More informationReprint 797. Development of a Thunderstorm. P.W. Li
Reprint 797 Development of a Thunderstorm Nowcasting System in Support of Air Traffic Management P.W. Li AMS Aviation, Range, Aerospace Meteorology Special Symposium on Weather-Air Traffic Management Integration,
More informationP474 SYDNEY AIRPORT WIND SHEAR ENCOUNTER - 15 APRIL 2007
P474 SYDNEY AIRPORT WIND SHEAR ENCOUNTER - 15 APRIL 2007 Rodney Potts* 1, Barry Hanstrum 2 and Peter Dunda 2 1. CAWCR, Bureau of Meteorology, Melbourne, VIC, Australia 2. Bureau of Meteorology, Sydney,
More informationRemote Sensing ISSN
Remote Sens. 2010, 2, 2127-2135; doi:10.3390/rs2092127 Communication OPEN ACCESS Remote Sensing ISSN 2072-4292 www.mdpi.com/journal/remotesensing Determination of Backscatter-Extinction Coefficient Ratio
More informationBMeteorologische Zeitschrift, PrePub DOI /metz/2017/0858
BMeteorologische Zeitschrift, PrePub DOI 10.1127/metz/2017/0858 2017 The authors Traffic Meteorology Application of spectral decomposition of LIDAR-based headwind profiles in windshear detection at the
More informationImpact of different cumulus parameterizations on the numerical simulation of rain over southern China
Impact of different cumulus parameterizations on the numerical simulation of rain over southern China P.W. Chan * Hong Kong Observatory, Hong Kong, China 1. INTRODUCTION Convective rain occurs over southern
More informationDepiction of complex airflow near Hong Kong International Airport using a Doppler LIDAR with a two-dimensional wind retrieval technique
Meteorologische Zeitschrift, Vol. 16, No. 5, 491-504 (October 2007) (published online 2007) c by Gebrüder Borntraeger 2007 Article Depiction of complex airflow near Hong Kong International Airport using
More informationInformation Note on the Webpage for Significant Convection Monitoring and Forecast
Information Note on the Webpage for Significant Convection Monitoring and Forecast The webpage displays both the real-time products for monitoring of significant convection and forecast products for significant
More informationWind data collected by a fixed-wing aircraft in the vicinity of a typhoon over the south China coastal waters
Wind data collected by a fixed-wing aircraft in the vicinity of a typhoon over the south China coastal waters P.W. Chan * and K.K. Hon Hong Kong Observatory, Hong Kong, China Abstract: The fixed-wing aircraft
More informationAVIATION APPLICATIONS OF A NEW GENERATION OF MESOSCALE NUMERICAL WEATHER PREDICTION SYSTEM OF THE HONG KONG OBSERVATORY
P452 AVIATION APPLICATIONS OF A NEW GENERATION OF MESOSCALE NUMERICAL WEATHER PREDICTION SYSTEM OF THE HONG KONG OBSERVATORY Wai-Kin WONG *1, P.W. Chan 1 and Ivan C.K. Ng 2 1 Hong Kong Observatory, Hong
More informationAN EMPIRICAL MODEL FOR AERODROME WIND FORECASTING DURING THE PASSAGE OF TROPICAL CYCLONES
P1.1 AN EMPIRICAL MODEL FOR AERODROME WIND FORECASTING DURING THE PASSAGE OF TROPICAL CYCLONES T. C. Cheung The Chinese University of Hong Kong Hong Kong China P. Cheung C. C. Lam * Hong Kong Observatory
More informationMETEOROLOGY. 1 The average height of the tropopause at 50 N is about A 14 km B 16 km C 11 km D 8 km
1 The average height of the tropopause at 50 N is about A 14 km B 16 km C 11 km D 8 km 2 In the lower part of the stratosphere the temperature A is almost constant B decreases with altitude C increases
More informationW.H. Leung, W.M. Ma and H.K. Yeung Hong Kong Observatory, Hong Kong, China
322 THE APPLICATION OF LIGHTNING DENSITY MAP IN THE ANALYSIS OF A SEVERE RAINSTORM CASE IN HONG KONG W.H. Leung, W.M. Ma and H.K. Yeung Hong Kong Observatory, Hong Kong, China 1. INTRODUCTION On 22 July
More informationDEPARTMENT OF GEOSCIENCES SAN FRANCISCO STATE UNIVERSITY. Metr Fall 2012 Test #1 200 pts. Part I. Surface Chart Interpretation.
DEPARTMENT OF GEOSCIENCES SAN FRANCISCO STATE UNIVERSITY NAME Metr 356.01 Fall 2012 Test #1 200 pts Part I. Surface Chart Interpretation. Figure 1. Surface Chart for 1500Z 7 September 2007 1 1. Pressure
More informationA Path to Shed Light on the Windshear. Enhancing the windshear alerting systems in airports by integrating a LiDAR-based system.
DTN WHITE PAPER A Path to Shed Light on the Windshear Enhancing the windshear alerting systems in airports by integrating a LiDAR-based system August 2017 www.dtn.com / 1.800.509.8927 2017 DTN, Inc Summary
More informationField study of the latest transmissometers at Hong Kong International Airport
Field study of the latest transmissometers at Hong Kong International Airport P. W. Chan Hong Kong Observatory 134A Nathan Road, Kowloon, Hong Kong, China Tel:+852 2926 8435, Fax: +852 2311 9448, Email:
More informationAviation Reports, Forecasts and Warnings I
Aviation Reports, Forecasts and Warnings I SPECI criteria Element Crosswind Supplementary information Special report in the SPECI code form crosswind based on the 10-minute mean wind changes from less
More informationand SUMMARY preliminary parameters. 1.1 MET/14-IP/ /15 In line 1.2 WORLD INTERNATIONAL CIVIL AVIATION ORGANIZATION 2/6/14 English only
INTERNATIONAL CIVIL AVIATION ORGANIZATION Meteorology (MET) Divisional Meeting (2014) WORLD METEOROLOGICAL ORGANIZATION Commission for Aeronautical Meteorology Fifteenth Session MET/14-IP/ /15 2/6/14 English
More informationP13A.4 THE AIR FRANCE 358 INCIDENT OF 2 AUGUST 2005 AT TORONTO INTERNATIONAL AIRPORT. Paul Joe
P13A.4 THE AIR FRANCE 358 INCIDENT OF 2 AUGUST 2005 AT TORONTO INTERNATIONAL AIRPORT Paul Joe Environment Canada, 4905 Dufferin St., Toronto, Ontario, CANADA M3H 5T4 email: paul.joe@ec.gc.ca tel: 416 739
More informationFronts in November 1998 Storm
Fronts in November 1998 Storm Much of the significant weather observed in association with extratropical storms tends to be concentrated within narrow bands called frontal zones. Fronts in November 1998
More informationTraffic and Weather. Soaring Safety Foundation. Tom Johnson CFIG
Traffic and Weather Soaring Safety Foundation Tom Johnson CFIG Weather Contents Weather Gathering Sources Weather Acquisition Enroute Weather Analysis Weather Hazards Weather in the Landing Pattern Basic
More informationScience Olympiad Meteorology Quiz #2 Page 1 of 8
1) The prevailing general direction of the jet stream is from west to east in the northern hemisphere: 2) Advection is the vertical movement of an air mass from one location to another: 3) Thunderstorms
More informationMET Lecture 34 Downbursts
MET 4300 Lecture 34 Downbursts Downbursts A strong downdraft that originates within the lower part of a cumulus cloud or thunderstorms and spreads out at the surface Downbursts do not require strong thunderstorms
More informationCASE STUDY OF THE NOVEMBER WINDSTORM IN SOUTH CENTRAL COLORADO
32 CASE STUDY OF THE 12-13 NOVEMBER WINDSTORM IN SOUTH CENTRAL COLORADO Paul Wolyn * NOAA/NWS Pueblo, CO 1. INTRODUCTION During the evening and early morning of 12-13 November 2011, a damaging downslope
More informationWEATHER THEORY. Weather Theory Page 100 Aviation Seminars. Measurement Of Temperature, Pressure And Moisture. Stability (Cont)
Weather Theory Page 100 WEATHER THEORY Measurement Of Temperature, Pressure And Moisture The primary cause of all changes in the earth s weather is variation of solar energy received by the Earth s regions..
More informationESCI 344 Tropical Meteorology Lesson 7 Temperature, Clouds, and Rain
ESCI 344 Tropical Meteorology Lesson 7 Temperature, Clouds, and Rain References: Forecaster s Guide to Tropical Meteorology (updated), Ramage Tropical Climatology, McGregor and Nieuwolt Climate and Weather
More information1. Introduction. 2. Verification of the 2010 forecasts. Research Brief 2011/ February 2011
Research Brief 2011/01 Verification of Forecasts of Tropical Cyclone Activity over the Western North Pacific and Number of Tropical Cyclones Making Landfall in South China and the Korea and Japan region
More informationLagrangian Coherent Structure Analysis of Terminal Winds Detected by Lidar. Part II: Structure Evolution and Comparison with Flight Data
OCTOBER 2011 T A N G E T A L. 2167 Lagrangian Coherent Structure Analysis of Terminal Winds Detected by Lidar. Part II: Structure Evolution and Comparison with Flight Data WENBO TANG School of Mathematical
More informationGovernment of Sultanate of Oman Public Authority of Civil Aviation Directorate General of Meteorology. National Report To
Government of Sultanate of Oman Public Authority of Civil Aviation Directorate General of Meteorology National Report To Panel on Tropical Cyclones in the Bay of Bengal And Arabian Sea 43rd Session, India
More informationForecasting of Optical Turbulence in Support of Realtime Optical Imaging and Communication Systems
Forecasting of Optical Turbulence in Support of Realtime Optical Imaging and Communication Systems Randall J. Alliss and Billy Felton Northrop Grumman Corporation, 15010 Conference Center Drive, Chantilly,
More informationDLR Falcon Dropsonde Operation in T-PARC and Analysis of the Environment Surrounding Typhoons
DLR Falcon Dropsonde Operation in T-PARC and Analysis of the Environment Surrounding Typhoons Kotaro Bessho 1, Tetsuo Nakazawa 1 and Martin Weissmann 2 1 Meteorological Research Institute, Japan Meteorological
More informationWeather vs. Climate. Tucson NWS homepage:
Weather vs. Climate Tucson NWS homepage: www.nws.noaa.gov/twc/ A Weather Forecaster? Betty claims to know exactly when it s going to rain because her knee starts to hurt. Ms. Betty Martin of Newburgh,
More informationMechanical Turbulence Wind forms eddies as it blows around hanger, stands of trees or other obstructions
Turbulence Low-level Turbulence below 15,000 feet consists of Mechanical Turbulence Convective Turbulence Frontal Turbulence Wake Turbulence Mechanical Turbulence Wind forms eddies as it blows around hanger,
More informationWeather observations by aircraft reconnaissance inside Severe Typhoon Utor
Weather observations by aircraft reconnaissance inside Severe Typhoon Utor P. W. Chan, W. K. Wong and K. K. Hon Hong Kong Observatory, China Introduction Since 2009, the Hong Kong Observatory (HKO) has
More informationSteven Greco* and George D. Emmitt Simpson Weather Associates, Charlottesville, VA. 2. Experiments
3.3 INVESTIGATION OF FLOWS WITHIN COMPLEX TERRAIN AND ALONG COASTLINES USING AN AIRBORNE DOPPLER WIND LIDAR: OBSERVATIONS AND MODEL COMPARISONS Steven Greco* and George D. Emmitt Simpson Weather Associates,
More informationMODELING AND MEASUREMENTS OF THE ABL IN SOFIA, BULGARIA
MODELING AND MEASUREMENTS OF THE ABL IN SOFIA, BULGARIA P58 Ekaterina Batchvarova*, **, Enrico Pisoni***, Giovanna Finzi***, Sven-Erik Gryning** *National Institute of Meteorology and Hydrology, Sofia,
More informationInflow and Outflow through the Sea-to-Sky Corridor in February 2010: Lessons Learned from SNOW-V10 *
Inflow and Outflow through the Sea-to-Sky Corridor in February 2010: Lessons Learned from SNOW-V10 * Ruping Mo National Laboratory for Coastal and Mountain Meteorology, Environment Canada, Vancouver, BC,
More informationL. McMurdie, R. Houze, J. Zagrodnik, W. Petersen, M. Schwaller
L. McMurdie, R. Houze, J. Zagrodnik, W. Petersen, M. Schwaller International Atmospheric Rivers Conference, San Diego, CA, 9 August 2016 Goals of OLYMPEX Validate GPM satellite radar and passive microwave
More informationFoundations of Earth Science, 6e Lutgens, Tarbuck, & Tasa
Foundations of Earth Science, 6e Lutgens, Tarbuck, & Tasa Weather Patterns and Severe Weather Foundations, 6e - Chapter 14 Stan Hatfield Southwestern Illinois College Air masses Characteristics Large body
More informationNortheastern United States Snowstorm of 9 February 2017
Northeastern United States Snowstorm of 9 February 2017 By Richard H. Grumm and Charles Ross National Weather Service State College, PA 1. Overview A strong shortwave produced a stripe of precipitation
More informationFort Lewis, Washington (47 05'N, 'W)
Fort Lewis, Washington (47 05'N, 122 35'W) Full Year Climatology CONVENTIONS: The spelling of place names and geographical features are those used by the National Imagery and Mapping Agency (NIMA). All
More informationKey. Name: OBJECTIVES
Name: Key OBJECTIVES Correctly define: air mass, air pressure, anemometer, barometer, cyclone, dew point, front, isobar, isotherm, meteorology, precipitation, psychrometer, relative humidity, saturated,
More informationOBJECTIVE CALIBRATED WIND SPEED AND CROSSWIND PROBABILISTIC FORECASTS FOR THE HONG KONG INTERNATIONAL AIRPORT
P 333 OBJECTIVE CALIBRATED WIND SPEED AND CROSSWIND PROBABILISTIC FORECASTS FOR THE HONG KONG INTERNATIONAL AIRPORT P. Cheung, C. C. Lam* Hong Kong Observatory, Hong Kong, China 1. INTRODUCTION Wind is
More informationMAURITIUS METEOROLOGICAL SERVICES
MAURITIUS METEOROLOGICAL SERVICES CLIMATE FEBRUARY 2019 Introduction February 2019 was in mostly warm and dry. ENSO conditions and the Indian Ocean Dipole were neutral. However, the Inter Tropical Convergence
More informationName: Regents Earth Science. Weather and Climate - Review Questions
Name: Regents Earth Science Weather and Climate - Review Questions Date: Thayer - 279 1. People sometimes release substances into the atmosphere to increase the probability of rain by A) raising the air
More informationSynoptic Meteorology II: Frontogenesis Examples Figure 1
Synoptic Meteorology II: Frontogenesis Examples The below images, taken from the 1200 UTC 17 January 2019 GFS forecast run, provide examples of the contributions of deformation and divergence to frontogenesis.
More informationNational Meteorological Library and Archive
National Meteorological Library and Archive Fact sheet No. 4 Climate of the United Kingdom Causes of the weather in the United Kingdom The United Kingdom lies in the latitude of predominately westerly
More informationP2.2 REDUCING THE IMPACT OF NOISE ABATEMENT PRACTICES ON AIRPORT CAPACITY BY FORECASTING SITUATIONAL DEPENDENT AIRCRAFT NOISE PROPAGATION
P2.2 REDUCING THE IMPACT OF NOISE ABATEMENT PRACTICES ON AIRPORT CAPACITY BY FORECASTING SITUATIONAL DEPENDENT AIRCRAFT NOISE PROPAGATION R. Sharman* and T. Keller Research Applications Program National
More informationSAMPLE ASSESSMENT TASKS AVIATION ATAR YEAR 12
SAMPLE ASSESSMENT TASKS AVIATION ATAR YEAR 12 Copyright School Curriculum and Standards Authority, 2015 This document apart from any third party copyright material contained in it may be freely copied,
More informationBoundary Layer Turbulence Index: Progress and Recent Developments
Boundary Layer Turbulence Index: Progress and Recent Developments Kenneth L. Pryor Center for Satellite Applications and Research (NOAA/NESDIS) Camp Springs, MD 1. Introduction Turbulence is a frequently
More informationThe project that I originally selected to research for the OC 3570 course was based on
Introduction The project that I originally selected to research for the OC 3570 course was based on remote sensing applications of the marine boundary layer and their verification with actual observed
More information2014 海峽兩岸暨香港地區航空氣象技術講座
2014 海峽兩岸暨香港地區航空氣象技術講座 P W Li Vice chair Hong Kong Meteorological Society Senior Scientific Officer, Hong Kong Observatory pwli@hko.gov.hk www.meteorology.org.hk GUANGZHOU FIR HK FIR TAIPEI FIR About 276,000
More informationFor the operational forecaster one important precondition for the diagnosis and prediction of
Initiation of Deep Moist Convection at WV-Boundaries Vienna, Austria For the operational forecaster one important precondition for the diagnosis and prediction of convective activity is the availability
More informationChecklist Templates for Direct Observation and Oral Assessments (AMOB)
Checklist Templates for Direct Observation and Oral Assessments (AMOB) Competency Assessment System Hong Kong Observatory Hong Kong, China Prepared By: Signed Approved By: Signed Date: 20/08/2012 Date:
More informationNational Meteorological Library and Archive
National Meteorological Library and Archive Fact sheet No. 4 Climate of the United Kingdom Causes of the weather in the United Kingdom The United Kingdom lies in the latitude of predominately westerly
More information7.6 AEROSOL IMPACTS ON TROPICAL CYCLONES
7.6 AEROSOL IMPACTS ON TROPICAL CYCLONES William R. Cotton, Gustavo G. Carrio, and S Herbener Department of Atmospheric Science, Colorado State University, Fort Collins, Colorado 1. INTRODUCTION Previous
More informationP2.3 Performance of drop-counting rain gauges in an operational environment. P.W. Chan * and C.M. Li Hong Kong Observatory, Hong Kong, China
P2.3 Performance of drop-counting rain gauges in an operational environment P.W. Chan * and C.M. Li Hong Kong Observatory, Hong Kong, China 1. INRODUCION Located at a subtropical coastal area, it is quite
More informationMET Lecture 20 Mountain Snowstorms (CH16)
MET 4300 Lecture 20 Mountain Snowstorms (CH16) Learning Objectives Provide an overview of the importance and impacts of mountain snowstorms in the western US Describe how topography influence precipitation
More informationMAURITIUS METEOROLOGICAL SERVICES
MAURITIUS METEOROLOGICAL SERVICES CLIMATE NOVEMBER 2018 Introduction Climatologically speaking, November is a relatively dry month for Mauritius with a long term monthly mean rainfall of 78 mm. However,
More informationPlan for operational nowcasting system implementation in Pulkovo airport (St. Petersburg, Russia)
Plan for operational nowcasting system implementation in Pulkovo airport (St. Petersburg, Russia) Pulkovo airport (St. Petersburg, Russia) is one of the biggest airports in the Russian Federation (150
More informationINVESTIGATION FOR A POSSIBLE INFLUENCE OF IOANNINA AND METSOVO LAKES (EPIRUS, NW GREECE), ON PRECIPITATION, DURING THE WARM PERIOD OF THE YEAR
Proceedings of the 13 th International Conference of Environmental Science and Technology Athens, Greece, 5-7 September 2013 INVESTIGATION FOR A POSSIBLE INFLUENCE OF IOANNINA AND METSOVO LAKES (EPIRUS,
More informationFigure 1: Tephigram for radiosonde launched from Bath at 1100 UTC on 15 June 2005 (IOP 1). The CAPE and CIN are shaded dark and light gray,
Figure 1: Tephigram for radiosonde launched from Bath at 1100 UTC on 1 June 200 (IOP 1). The CAPE and CIN are shaded dark and light gray, respectively; the thin solid line partially bounding these areas
More informationATSC 2000 Final Fall 2005
ATSC 2000 Final Fall 2005 true/false /25 multiple choice /25 short answer /23 essay /10 total /83 or % True/False Indicate whether the sentence or statement is true or false. (25 questions 1% each) 1.
More informationStorm and Storm Systems Related Vocabulary and Definitions. Magnitudes are measured differently for different hazard types:
Storm and Storm Systems Related Vocabulary and Definitions Magnitude: this is an indication of the scale of an event, often synonymous with intensity or size. In natural systems, magnitude is also related
More information7.17 RAPIDS A NEW RAINSTORM NOWCASTING SYSTEM IN HONG KONG
7.17 RAPIDS A NEW RAINSTORM NOWCASTING SYSTEM IN HONG KONG Li Ping-Wah *, Wong Wai-Kin and Edwin S.T. Lai Hong Kong Observatory, 134A Nathan Road, Kowloon, Hong Kong 1. INTRODUCTION and the numerical forecast
More informationComplex Terrain (EDUCT) experiment, conducted by the National Center for Atmospheric
Alex Ameen Shenandoah Trip Paper I visited Shenandoah National Park on April 11, 2009 to investigate the Education in Complex Terrain (EDUCT) experiment, conducted by the National Center for Atmospheric
More information11/19/14. Chapter 11: Hurricanes. The Atmosphere: An Introduction to Meteorology, 12 th. Lutgens Tarbuck
Chapter 11: Hurricanes The Atmosphere: An Introduction to Meteorology, 12 th Lutgens Tarbuck Lectures by: Heather Gallacher, Cleveland State University! Hurricanes: " Hurricanes are intense centers of
More informationSevere Freezing Rain in Slovenia
Severe Freezing Rain in Slovenia Janez Markosek, Environmental Agency, Slovenia Introduction At the end of January and at the beginning of February 2014, severe and long-lasting freezing rain affected
More informationAnswer Key. Page 1 of 5
Answer Key Name: Score: [1] When telephoning a weather briefing facility for preflight weather information, pilots should state A. whether they intend to fly VFR only. B. the full name and address of the
More informationFun with Weather Maps! (no, really stop laughing) AOSC 200 Tim Canty
Fun with Weather Maps! (no, really stop laughing) AOSC 200 Tim Canty Class Web Site: http://www.atmos.umd.edu/~tcanty/aosc200 Topics for today: Observations Station Model Temperature Maps Pressure Maps
More informationInternational Civil Aviation Organization
CNS/MET SG/14 IP/19 International Civil Aviation Organization FOURTEENTH MEETING OF THE COMMUNICATIONS/NAVIGATION/SURVEILL ANCE AND METEOROLOGY SUB-GROUP OF APANPIRG (CNS/MET SG/14) Jakarta, Indonesia,
More informationAMDAR Forecast Applications. Richard Mamrosh NWS Green Bay, Wisconsin, USA
AMDAR Forecast Applications Richard Mamrosh NWS Green Bay, Wisconsin, USA AMDAR has many applications Aviation Low level wind shear Ceilings and visibilities Icing and turbulence Winter Storms Precipitation
More informationP4.11 SINGLE-DOPPLER RADAR WIND-FIELD RETRIEVAL EXPERIMENT ON A QUALIFIED VELOCITY-AZIMUTH PROCESSING TECHNIQUE
P4.11 SINGLE-DOPPLER RADAR WIND-FIELD RETRIEVAL EXPERIMENT ON A QUALIFIED VELOCITY-AZIMUTH PROCESSING TECHNIQUE Yongmei Zhou and Roland Stull University of British Columbia, Vancouver, BC, Canada Robert
More informationChapter 1 Anatomy of a Cyclone
Chapter 1 Anatomy of a Cyclone The Beast in the East 15-17 February 2003 Extra-tropical cyclone an area of low pressure outside of the tropics Other names for extra-tropical cyclones: Cyclone Mid-latitude
More informationSTATION If relative humidity is 60% and saturation vapor pressure is 35 mb, what is the actual vapor pressure?
STATION 1 Vapor pressure is a measure of relative humidity and saturation vapor pressure. Using this information and the information given in the problem, answer the following question. 1. If relative
More information25.1 Air Masses. Section 25.1 Objectives
Section 25.1 Objectives Explain how an air mass forms. List the four main types of air masses. Describe how air masses affect the weather of North America. Air Masses 25.1 Air Masses Differences in air
More informationWeather Related Factors of the Adelaide floods ; 7 th to 8 th November 2005
Weather Related Factors of the Adelaide floods ; th to th November 2005 Extended Abstract Andrew Watson Regional Director Bureau of Meteorology, South Australian Region 1. Antecedent Weather 1.1 Rainfall
More informationGuidance on Aeronautical Meteorological Observer Competency Standards
Guidance on Aeronautical Meteorological Observer Competency Standards The following guidance is supplementary to the AMP competency Standards endorsed by Cg-16 in Geneva in May 2011. Format of the Descriptions
More informationGuided Notes Weather. Part 2: Meteorology Air Masses Fronts Weather Maps Storms Storm Preparation
Guided Notes Weather Part 2: Meteorology Air Masses Fronts Weather Maps Storms Storm Preparation The map below shows North America and its surrounding bodies of water. Country borders are shown. On the
More information2) What general circulation wind belt is the place of origin for hurricanes? A) westerlies B) trade winds C) doldrums D) horse latitudes
Meteo 1010 Homework 6 1) What is the difference between a typhoon and a hurricane? A) A hurricane is a true tropical cyclone, but a typhoon is not. B) A hurricane is stronger than a typhoon. C) They represent
More informationP4.10. Kenichi Kusunoki 1 * and Wataru Mashiko 1 1. Meteorological Research Institute, Japan
P4. DOPPLER RADAR INVESTIGATIONS OF THE INNER CORE OF TYPHOON SONGDA (24) Polygonal / elliptical eyewalls, eye contraction, and small-scale spiral bands. Kenichi Kusunoki * and Wataru Mashiko Meteorological
More information1. Which weather map symbol is associated with extremely low air pressure? A) B) C) D) 2. The diagram below represents a weather instrument.
1. Which weather map symbol is associated with extremely low air pressure? 2. The diagram below represents a weather instrument. Which weather variable was this instrument designed to measure? A) air pressure
More informationMAURITIUS METEOROLOGICAL SERVICES
MAURITIUS METEOROLOGICAL SERVICES CLIMATE DECEMBER 2018 Introduction December 2018 was warm and wet. The mean monthly rainfall recorded islandwise was 261 mm which is 151 % of the normal. ENSO conditions
More informationNAM-WRF Verification of Subtropical Jet and Turbulence
National Weather Association, Electronic Journal of Operational Meteorology, 2008-EJ3 NAM-WRF Verification of Subtropical Jet and Turbulence DOUGLAS N. BEHNE National Weather Service, Aviation Weather
More information9.10 NUMERICAL SIMULATIONS OF THE WAKE OF KAUAI WITH IMPLICATIONS FOR THE HELIOS FLIGHTS
9.10 NUMERICAL SIMULATIONS OF THE WAKE OF KAUAI WITH IMPLICATIONS FOR THE HELIOS FLIGHTS T. P. Lane 1, R. D. Sharman 1, R G. Frehlich 1, J. M. Brown 2, J. T. Madura 3, and L. J. Ehernberger 4 1 National
More informationRegional influence on road slipperiness during winter precipitation events. Marie Eriksson and Sven Lindqvist
Regional influence on road slipperiness during winter precipitation events Marie Eriksson and Sven Lindqvist Physical Geography, Department of Earth Sciences, Göteborg University Box 460, SE-405 30 Göteborg,
More information