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 operational command of the Commanding Officer, Naval Maritime Forecast Center/Joint Typhoon Warning Center (NMFC/JTWC), Pearl Harbor, Hawaii.
JTWC was established on 1 May 1959 when Commander-in- Chief, US Pacific Command (USCINCPAC) directed Commander-in-Chief, Pacific Fleet to provide a single tropical cyclone warning center for the western North Pacific region. 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 TC season and details operationally or meteorologically significant cyclones noted within the JTWC Area of Responsibility. 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.
Record low tropical cyclone activity was observed in the western North Pacific Ocean, continuing a trend that started in 2005, with only 19 TCs observed compared to the long term average of 31. Super Typhoon Megi (15W) was the only cyclone to reach super typhoon intensity. Megi was a significant cyclone because it occurred during the Office of Naval Research sponsored Impact of Typhoons on the Pacific/Tropical Cyclone Structure 2010 (ITOP/TCS-10) field campaign. Megi was penetrated by United States Air Force Reserve WC-130J reconnaissance aircraft. During one of these penetrations, the Step Frequency Microwave Radiometer (SFMR) measured the highest tropical cyclone wind speed ever recorded, 86 m/s (172 kts). Typhoon Kompasu (08W) was operationally significant because it made landfall on Okinawa as a strong typhoon and on South Korea as a minimal typhoon.
The Southern Hemisphere activity was also below normal, with 24 cyclones observed compared to an average of 28 and the North Indian Ocean experienced normal activity with 5 cyclones. Tropical Cyclones Phet and Giri were notable cyclones in the Arabian Sea and Bay of Bengal, respectively. Phet underwent rapid intensification off the coast of Oman, then moved across the eastern part of the country, into the Gulf of Oman and then into Pakistan. Giri also underwent rapid intensification just prior to making landfall in Myanmar. Both cyclones resulted in USPACOM directed Humanitarian Assistance/Disaster Relief responses.
The ITOP/TCS-10 field campaign, aimed at assessing the impacts typhoons have on the ocean, brought significantly enhance observations to the western North Pacific during the months of August, September and early October. Additionally, it provided an opportunity for Typhoon Duty Officer qualified personnel, Mr. Matt Kucas, Mr. Rick Ballucanag, and LT Chris Morris to fly on the WC-130J as mission scientists.
During 2010, NMFC/JTWC continued funding upgrades to the Geophysical Fluid Dynamics Lab-Navy (GFDN) tropical cyclone following mesoscale model. These upgrades included both physics updates and 3-dimensional air-ocean coupling for the Indian Ocean and the Southern Hemisphere. Weather satellite data remained the mainstay of the TC reconnaissance mission at the JTWC. Satellite analysts exploited a wide variety of conventional and microwave satellite data to produce over 7,770 position and intensity estimates (fixes), primarily using the USAF Mark IVB and the USN FMQ-17 satellite direct readout systems. The Mark IVB began receiving an upgraded capability to receive and process X-band signals, providing real-time access to the Aqua and Terra satellites. The JTWC also continued to use 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 to make TC fixes.
JTWC continued to advocate for improved satellite reconnaissance capability, including continuation of the Navy Research Labs Coriolis/WindSAT, an ocean surface vector wind capable 43 channel microwave sensor on the Defense Weather Satellite System (DWSS), and exploitation of international remote sensing capabilities, including the Indian Space Research Organizations OceanSAT-2 and the joint Meteo France / Indian Mega Tropiques.
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, and Air Force Weather Agency (AFWA) for continued development of numerical TC models and forecast aids. Operational support and enhancements to the ATCF system continued, making development and issuance of tropical cyclone warnings as streamlined as possible for forecasters.
Additionally, in an effort to provide greater support to assets in the southern hemisphere and the northern Indian Ocean, JTWC extended warning periods in 2010 from 72hrs to 120hrs for those basins; providing 5-day forecasts to enhance resource protection for the entire JTWC AOR.
Behind all these efforts are the dedicated team of men and women, military and civilian at NMFC/JTWC. Special thanks to the entire N6 Department for their outstanding IT support and the administrative and budget staff who worked tirelessly to ensure JTWC had the necessary resourcesvto get the mission done.
Special thanks also to: FNMOC for their operational data and modeling support; the NRLMRY and ONR for its dedicated research; the National Oceanic and Atmospheric Administration National Environmental Satellite, Data, and Information Service for satellite support; for their high quality support; all the men and women of the ships and facilities ashore throughout the JTWC area of responsibility; 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 support and continued development of the ATCF system.