As a student, he concentrated on topics related to
tropical climate variability including El Nino/Southern Oscillation,
monsoons, tropical cyclones and large-scale Atlantic climatology. The
focus of his more recent studies, including his postdoctoral work, has
been on observational aspects of hurricane structure and intensity
variations and prediction. Much of that work has lead to the
development of forecast applications that have been transferred to
operations at the NESDIS/Satellite Analysis Branch, the National
Hurricane Center and the Joint Typhoon Warning Center. In 2004, he
received the NOAA David Johnson Award for basic research for improving
the understanding of tropical phenomenon and predicting tropical
cyclone intensity, accompanied by exemplary transfer of the results
into operational products.
Current research includes the utilization of satellite and other
observations to improve scientific understanding, diagnosis and
forecasting capabilities of tropical cyclone genesis and structure
change, the development and documentation of operational tropical
cyclone forecasting techniques, and the transfer of such techniques to
the operational setting.
Since 1991, he has published more than 25 articles on tropical
cyclones, mesoscale meteorology and tropical climatology in the
refereed literature.
Knaff, J.A., and R.M. Zehr, 2007: Reexamination of Tropical Cyclone
Pressure Wind Relationships. Wea. Forecasting, 22:1, 71–88.
Kossin, J. P., J. A. Knaff, H. I. Berger, D. C. Herndon, T. A.
Cram, C. S. Velden, R. J. Murnane, and J. D. Hawkins, 2007: Estimating
hurricane wind structure in the absence of aircraft reconnaissance.
Wea. Forecasting, 22:1, 89–101.
Bessho, K., M. DeMaria, J.A. Knaff, 2006: Tropical Cyclone Wind
Retrievals from the Advanced Microwave Sounder Unit (AMSU):
Application to Surface Wind Analysis. J. of Applied Meteorology.
45:3, 399 - 415.
Chen, S.S., J.A. Knaff, and F.D. Marks, Jr., 2006: Effects of
Vertical Wind Shear and Storm Motion Tropical Cyclone Rainfall
Asymmetries Deduced from TRMM. Monthly Weather Review. 3190-3208.
DeMaria, M,. J.A. Knaff, J. Kaplan. 2006: On the Decay of Tropical
Cyclone Winds Crossing Narrow Landmasses. Journal of Applied
Meteorology and Climatology. 45:3, 491–499.
Demuth, J., M. DeMaria, and J.A. Knaff, 2006: Improvement of
Advanced Microwave Sounding Unit Tropical Cyclone Intensity and Size
Estimation Algorithms, Journal of Applied Meteorology and Climatology,
45:11, 1573–1581.
Landsea, C.W., B.A. Harper, K. Hoarau, and J.A. Knaff, 2006: Can
we detect trends in extreme tropical cyclones?. Science, 313, 452-
454.
Lindsey, D.T., D.W. Hillger, L.D. Grasso, J.A. Knaff, and J.F.
Dostalek, 2006: GOES Climatology and Analysis of Thunderstorms with
Enhanced 3.9 µm Reflectivity. Mon. Wea. Rev., 134-9, 2342–2353.
Mueller, K.J., M. DeMaria, J.A. Knaff, T.H. Vonder Haar:, 2006:
Objective Estimation of Tropical Cyclone Wind Structure from Infrared
Satellite Data. Wea. Forecasting, 21:6, 990–1005.