The Annual Tropical Cyclone Report (ATCR) is prepared by the staff of the Joint Typhoon Warning Center (JTWC), a jointly manned United States Air Force/Navy organization under the command of the Commanding Officer, Joint Typhoon Warning Center.
The original JTWC was established on 1 May 1959 when the Joint Chiefs of Staff directed Commanderin- Chief, US Pacific Command (USCINCPAC) to provide a single tropical cyclone warning center for the western North Pacific region. USCINCPAC delegated the tropical cyclone forecast and warning mission to Commander, Pacific Fleet. A subsequent USCINCPAC directive further tasked Commander, Pacific Air Force to provide for tropical cyclone (TC) reconnaissance support to the JTWC. Currently, JTWC operations are guided by USPACOM Instruction 0539.1 and Pacific Air Forces Instruction 15-101.
This edition of the ATCR documents the 2012 TC season and details operationally or meteorologically significant cyclones noted within the JTWC Area of Responsibility (AOR). Details are provided to describe either significant challenges and/or shortfalls in the TC warning system and to serve as a focal point for future research and development efforts. Also included are tropical cyclone reconnaissance statistics and a summary of tropical cyclone research or technique development that members of JTWC were involved.
Continued below average tropical cyclone activity was observed in the western North Pacific Ocean, with only 27 TCs observed compared to the long term average of 31. There were four cyclones that reached super typhoon intensity. The TC formation region shifted eastward when compared to 2011 and displayed characteristics common during ENSO neutral conditions. Many of the 2012 TCs exhibited “S” shaped, looping, or generally erratic tracks, especially in the east Philippine Sea and South China Sea. Okinawa suffered three direct hits between late August and late September by Typhoon Bolaven (16W), Super Typhoon Sanba (17W), and Super Typhoon Jelawat (18W) with five other passages within 150 miles. Guam was again spared from direct tropical cyclone impacts, with Typhoon Sanvu (03W) passing just west of the island as a weak tropical storm. Department of Defense (DoD) bases in South Korea and mainland Japan were impacted by four and three tropical cyclones, respectively.
The Southern Hemisphere activity also continued a below normal trend, with 21 cyclones observed compared to an average of 28. A large majority of Southern Hemisphere cyclones occurred in the south Indian Ocean, with only four in the South Pacific, five around Australia and 12 occurring east of 100 degrees east longitude. The Northern Indian Ocean experienced near normal activity with 4 cyclones, with two in the Arabian Sea and two in the Bay of Bengal. All of the cyclones in the Northern Indian Ocean were weak, with peak winds of 50 knots or less.
Weather satellite data remained the mainstay of the TC reconnaissance mission to support the JTWC. Satellite analysts exploited a wide variety of conventional and microwave satellite data to produce over 8,500 position and intensity estimates (fixes), primarily using the USAF Mark IVB and the USN FMQ-17 satellite direct readout systems. Geo-located microwave satellite imagery overlays available via the Automated Tropical Cyclone Forecast (ATCF) system from Fleet Numerical Meteorology and Oceanography Center and the Naval Research Lab Monterey were also used by JTWC to make TC fixes thus providing additional data for TC location and intensity.
JTWC also continues to utilize radar derived TC position information from numerous U.S. owned/operated weather radars as well as from international sources. Antenna site selection and budget challenges have delayed the replacement of the WSR-88D Doppler Weather Radar at Kadena AB that was destroyed in 2011 by Super Typhoon Songda.
In 2012, the Air Force cancelled the Defense Weather Satellite System program. As a result, the Joint Requirements Oversight Council identified 12 DoD Meteorological and Oceanographic (METOC) collection requirement gaps. Several identified gaps relate to tropical cyclone reconnaissance, including Ocean Surface Vector Winds (OSVW), Tropical Cyclone Intensity, and Theater Weather Imagery. A space based environmental monitoring analysis of alternatives is currently underway to identify mitigation strategies for these gaps. Additionally, the announcement from the Japan Meteorological Agency that future geostationary satellites (Himawari 8 and 9) will not have a direct readout capability has caused JTWC to engage with Air Force, Navy, and NOAA to ensure critical western North Pacific geostationary satellite data will be available for TC reconnaissance when Himawari 8 becomes operational. The Air Forces’ Mark IVB system had several upgrades in 2012, including adding a second geostationary satellite dish, receipt and processing of NOAA’s NPP Suomi, China Meteorological Administration’s FengYun 3A/3B, and Korea Meteorological Administration’s COMS-1.
JTWC continued to collaborate with TC forecast support and research organizations such as the Fleet Numerical Meteorology and Oceanography Center (FNMOC), Naval Research Laboratory, Monterey (NRLMRY), Naval Post Graduate School, the Office of Naval Research (ONR), Air Force Weather Agency (AFWA), and National Oceanic and Atmospheric Administration (NOAA) Line Offices for continued development of TC reconnaissance tools, numerical models and forecast aids. JTWC also funded upgrades to the GFDN model, as well as, adaptation of intensity forecast aids (SHIPS-RI and LGEM) for use in the U.S. Pacific Command (USPACOM) AOR.
The Techniques Development Branch (TECHDEV) remained the voice of JTWC to the research and development community. They worked with researchers from the University of Hawaii, University of Arizona, Naval Post Graduate School, and other agencies on a variety of promising projects. They helped JTWC refine its TC formation potential process via the Low-Medium-High checklist. This process and checklist was presented at the 2012 American Meteorological Service Conference on Hurricanes and Tropical Meteorology. TECHDEV also worked on product enhancements, including displaying JTWC products in Google Earth. Behind all these efforts are the dedicated team of men and women, military and civilian at JTWC.
Special thanks to the entire JTWC N6 Department for their outstanding IT support and the administrative and budget staff who worked tirelessly to ensure JTWC had the necessary resources to get the mission done in extremely volatile financial times.
A Special thanks also to: FNMOC for their operational data and modeling support; the NRLMRY and ONR for its dedicated TC research; the NOAA National Environmental Satellite, Data, and Information Service for satellite reconnaissance support; Dr. John Knaff, Mr. Jeff Hawkins, Dr. Mark DeMaria, and Mr. Chris Velden for their continuing efforts to exploit remote sensing technologies in new and innovative ways; Mr. Charles R. “Buck” Sampson, Ms. Ann Schrader, Mr. Mike Frost, and Mr. Chris Sisko for their outstanding support and continued development of the ATCF system.