Tropical Cyclone one- and ten-minute ‘Best Track' Maximum Winds compared with Satellite-Only Estimates for Western North Pacific and Indian Ocean Basins

Estimation of ‘Best Track' Tropical Cyclone (TC) maximum wind speeds using the WMO 10-minute wind standard by Japan Meteorological Agency and Indian Meteorological Department in the Western Pacific (WPAC) and Indian Ocean basins, respectively, show differences of as much as 30% with the corresponding 1-minute ‘Best Track' maximum wind values derived by the U. S. Joint Typhoon Warning Center. This is well in excess of the expected 5% difference between 1- and 10-minute over-ocean wind speeds. Significant differences also exist between ‘Best Track' and objectively-derived, satellite-based 1-minute values from the Advanced Dvorak Technique (ADT) and SATellite CONsensus methods. These 1-minute differences, which can also be as large as 30%, give rise to a wide range of intensity estimates for use in various numerical prediction studies on weather and climate time scales (days to years). In addition, ‘Best Track' and satellite values use different relations to estimate minimum pressure from satellite-based maximum wind values. Since many model evaluations utilize minimum pressure to evaluate model performance, these different pressure-wind relations give rise to yet another level of uncertainty in TC intensity estimation and model validation. This study documents the level of uncertainty in TC intensity estimation between these various standards of observation for storms in the ‘major storm' category.