An Automated, Objective, Multiple-Satellite-Platform Tropical Cyclone Surface Wind Analysis

AbstractA method to estimate objectively the surface wind fields associated with tropical cyclones using only data from multiple satellite platforms and satellite-based wind retrieval techniques is described. The analyses are computed on a polar grid using a variational data-fitting method that allows for the application of variable data weights to input data. The combination of gross quality control and the weighted variational analysis also produces wind estimates that have generally smaller errors than do the raw input data. The resulting surface winds compare well to the NOAA Hurricane Research Division H*Wind aircraft reconnaissance–based surface wind analyses, and operationally important wind radii estimated from these wind fields are shown to be generally more accurate than those based on climatological data. Most important, the analysis system produces global tropical cyclone surface wind analyses and related products every 6 h—without aircraft reconnaissance data. Also, the analysis and products are available in time for consideration by forecasters at the Joint Typhoon Warning Center, the Central Pacific Hurricane Center, and the National Hurricane Center in preparing their forecasts and advisories. This Multiplatform Tropical Cyclone Surface Wind Analysis (MTCSWA) product is slated to become an operationally supported product at the National Environmental Satellite Data and Information Service (NESDIS). The input data, analysis method, products, and verification statistics associated with the MTCSWA are discussed within.

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The Intensity Forecasting Experiment: A NOAA Multiyear Field Program for Improving Tropical Cyclone Intensity Forecasts

Bulletin of the American Meteorological Society ◽

10.1175/bams-87-11-1523 ◽

2006 ◽

Vol 87 (11) ◽

pp. 1523-1538 ◽

Cited By ~ 113

Author(s):

Robert Rogers ◽

Sim Aberson ◽

Michael Black ◽

Peter Black ◽

Joe Cione ◽

...

Keyword(s):

Life Cycle ◽

Tropical Cyclone ◽

Field Experiments ◽

Three Dimensional ◽

Information Service ◽

Environmental Modeling ◽

Intensity Change ◽

Wind Fields ◽

Research Division ◽

Tropical Cyclone Intensity Forecasts

In 2005, NOAA's Hurricane Research Division (HRD), part of the Atlantic Oceanographic and Meteorological Laboratory, began a multiyear experiment called the Intensity Forecasting Experiment (IFEX). By emphasizing a partnership among NOAA's HRD, Environmental Modeling Center (EMC), National Hurricane Center (NHC), Aircraft Operations Center (AOC), and National Environmental Satellite Data Information Service (NESDIS), IFEX represents a new approach for conducting hurricane field program operations. IFEX is intended to improve the prediction of tropical cyclone (TC) intensity change by 1) collecting observations that span the TC life cycle in a variety of environments; 2) developing and refining measurement technologies that provide improved real-time monitoring of TC intensity, structure, and environment; and 3) improving the understanding of the physical processes important in intensity change for a TC at all stages of its life cycle. This paper presents a summary of the accomplishments of IFEX during the 2005 hurricane season. New and refined technologies for measuring such fields as surface and three-dimensional wind fields, and the use of unmanned aerial vehicles, were achieved in a variety of field experiments that spanned the life cycle of several tropical cyclones, from formation and early organization to peak intensity and subsequent landfall or extratropical transition. Partnerships with other experiments during 2005 also expanded the spatial and temporal coverage of the data collected in 2005. A brief discussion of the plans for IFEX in 2006 is also provided.

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Tropical Cyclone Wind Retrievals from the Advanced Microwave Sounding Unit: Application to Surface Wind Analysis

Journal of Applied Meteorology and Climatology ◽

10.1175/jam2352.1 ◽

2006 ◽

Vol 45 (3) ◽

pp. 399-415 ◽

Cited By ~ 32

Author(s):

Kotaro Bessho ◽

Mark DeMaria ◽

John A. Knaff

Keyword(s):

Tropical Cyclone ◽

Wind Direction ◽

Surface Wind ◽

Wind Fields ◽

Directional Bias ◽

Wind Speeds ◽

Research Division ◽

Microwave Sounding Unit ◽

Microwave Sounding ◽

Advanced Microwave Sounding Unit

Abstract Horizontal winds at 850 hPa from tropical cyclones retrieved using the nonlinear balance equation, where the mass field was determined from Advanced Microwave Sounding Unit (AMSU) temperature soundings, are compared with the surface wind fields derived from NASA's Quick Scatterometer (QuikSCAT) and Hurricane Research Division H*Wind analyses. It was found that the AMSU-derived wind speeds at 850 hPa have linear relations with the surface wind speeds from QuikSCAT or H*Wind. There are also characteristic biases of wind direction between AMSU and QuikSCAT or H*Wind. Using this information to adjust the speed and correct for the directional bias, a new algorithm was developed for estimation of the tropical cyclone surface wind field from the AMSU-derived 850-hPa winds. The algorithm was evaluated in two independent cases from Hurricanes Floyd (1999) and Michelle (2001), which were observed simultaneously by AMSU, QuikSCAT, and H*Wind. In this evaluation the AMSU adjustment algorithm for wind speed worked well. Results also showed that the bias correction algorithm for wind direction has room for improvement.

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Global Scatterometer Observations of the Structure of Tropical Cyclone Wind Fields

Monthly Weather Review ◽

10.1175/mwr-d-20-0196.1 ◽

2020 ◽

Vol 148 (11) ◽

pp. 4673-4692

Author(s):

Ali Tamizi ◽

Ian R. Young ◽

Agustinus Ribal ◽

Jose-Henrique Alves

Keyword(s):

Tropical Cyclone ◽

Surface Wind ◽

Radial Distance ◽

Wind Fields ◽

Forward Movement ◽

Left Right Asymmetry ◽

The Right ◽

Very Large Database ◽

Left Front ◽

Tropical Cyclone Center

AbstractA very large database containing 24 years of scatterometer passes is analyzed to investigate the surface wind fields within tropical cyclones. The analysis confirms the left–right asymmetry of the wind field with the strongest winds directly to the right of the tropical cyclone center (Northern Hemisphere). At values greater than 2 times the radius to maximum winds, the asymmetry is approximately equal to the storm velocity of forward movement. Observed wind inflow angle (i.e., storm motion not subtracted) is shown to vary both radially and azimuthally within the tropical cyclone. The smallest observed wind inflow angles are found in the left-front quadrant with the largest values in the right-rear quadrant. As the velocity of forward movement increases and the central pressure decreases, observed inflow angles ahead of the storm decrease and those behind the storm increase. In the right-rear quadrant, the observed inflow angle increases with radius from the storm center. In all other quadrants, the observed inflow angle is approximately constant as a function of radial distance.

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Tropical Cyclone Inner-Core Kinetic Energy Evolution

Monthly Weather Review ◽

10.1175/2008mwr2268.1 ◽

2008 ◽

Vol 136 (12) ◽

pp. 4882-4898 ◽

Cited By ~ 71

Author(s):

Katherine S. Maclay ◽

Mark DeMaria ◽

Thomas H. Vonder Haar

Keyword(s):

Tropical Cyclone ◽

Kinetic Energy ◽

Inner Core ◽

Surface Wind ◽

Statistical Testing ◽

Vertical Shear ◽

Structure Evolution ◽

Wind Fields ◽

Secondary Eyewall Formation ◽

Wind Structure

Abstract Tropical cyclone (TC) destructive potential is highly dependent on the distribution of the surface wind field. To gain a better understanding of wind structure evolution, TC 0–200-km wind fields from aircraft reconnaissance flight-level data are used to calculate the low-level area-integrated kinetic energy (KE). The integrated KE depends on both the maximum winds and wind structure. To isolate the structure evolution, the average relationship between KE and intensity is first determined. Then the deviations of the KE from the mean intensity relationship are calculated. These KE deviations reveal cases of significant structural change and, for convenience, are referred to as measurements of storm size [storms with greater (less) KE for their given intensity are considered large (small)]. It is established that TCs generally either intensify and do not grow or they weaken/maintain intensity and grow. Statistical testing is used to identify conditions that are significantly different for growing versus nongrowing storms in each intensification regime. Results suggest two primary types of growth processes: (i) secondary eyewall formation and eyewall replacement cycles, an internally dominated process, and (ii) external forcing from the synoptic environment. One of the most significant environmental forcings is the vertical shear. Under light shear, TCs intensify but do not grow; under moderate shear, they intensify less but grow more; under very high shear, they do not intensify or grow. As a supplement to this study, a new TC classification system based on KE and intensity is presented as a complement to the Saffir–Simpson hurricane scale.

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Development and Testing of Tropical Cyclone Parametric Wind Models Tailored for Midlatitude Application—Preliminary Results

Journal of Applied Meteorology and Climatology ◽

10.1175/jam2407.1 ◽

2006 ◽

Vol 45 (9) ◽

pp. 1244-1260 ◽

Cited By ~ 23

Author(s):

Allan W. MacAfee ◽

Garry M. Pearson

Keyword(s):

Tropical Cyclone ◽

Surface Wind ◽

Angular Size ◽

Absolute Error ◽

Parametric Models ◽

Wind Fields ◽

Low Latitude ◽

New Techniques ◽

Qualitative And Quantitative ◽

Using Data

Abstract Over the years, researchers have developed parametric wind models to depict the surface winds within a tropical cyclone (TC). Most models were developed using data from aircraft flights into low-latitude (south of 30°N) TCs in the Atlantic Ocean, Gulf of Mexico, and Caribbean Sea. Such models may not adequately reproduce the midlatitude TC wind field where synoptic interaction and acceleration are more pronounced. To tailor these models for midlatitude application, latitude-dependent angular size and shape details were added by using new techniques to set values for model input parameters and by incorporating additional field-shaping procedures. A method to assess the different techniques and field-shaping procedures was developed in which qualitative and quantitative assessment was performed using five parametric models and samples of buoy and 2D surface wind data. Contingency tables and statistical scores such as mean absolute error and bias were used to select the techniques and procedures that create the most realistic depiction of low- and midlatitude TC surface wind fields.

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Preliminary Analysis of Wind Retrieval Based on GF-3 Wave Mode Images

10.20944/preprints201804.0223.v2 ◽

2018 ◽

Author(s):

Lei Wang ◽

Bing Han ◽

Xinzhe Yuan ◽

Bin Lei ◽

Chibiao Ding ◽

...

Keyword(s):

Wind Speed ◽

Incidence Angle ◽

Surface Wind ◽

Wave Mode ◽

Azimuth Angle ◽

Calibration Constant ◽

Wind Fields ◽

Wind Retrieval ◽

Geophysical Model ◽

The Cross

In this paper, we analyze the measurements of the normalized radar cross-section(NRCS) in Wave Mode for Chinese C-band Gaofen-3(GF-3) synthetic aperture radar (SAR). Based on 2779 images from GF-3 quad-polarization SAR in Wave Mode and collocated wind vectors from ERA-Interim, we verify the feasibility of using ocean surface wind fields and VV-polarized NRCS to perform normalized calibration. The method uses well-validated empirical C-band geophysical model function (CMOD4) to estimate the calibration constant for each beam. The Amazon rainforest experiment results show that the accuracy of obtained calibration constant meets the requirements. In addition, the relationship between cross-pol NRCS and wind vectors is discussed. The cross-pol NRCS increases linearly with wind speed and it has an approximate cosine modulation with the wind direction when the wind speed is greater than 8m/s. The cross-polarized system noise floor is low enough to ignore it in wind retrieval. Furthermore, we also investigate the properties of the polarization ratio, denoted PR, and show that it is dependent on incidence angle and azimuth angle. Two empirical models of the PR are fitted, one as a function of incidence angle only, the other with additional dependence on azimuth angle. Assessments show that the σ_VV^0 retrieved from new PR models as well as σ_HH^0 is in good agreement with σ_VV^0 extracted from SAR images directly. And it is also shown that considering the azimuth angle can improve polarization conversion accuracy.

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Wind Structure Discrepancies between Two Best Track Datasets for Western North Pacific Tropical Cyclones

Monthly Weather Review ◽

10.1175/mwr-d-16-0163.1 ◽

2016 ◽

Vol 144 (12) ◽

pp. 4533-4551 ◽

Cited By ~ 3

Author(s):

Jinjie Song ◽

Philip J. Klotzbach

Keyword(s):

Tropical Cyclone ◽

North Pacific ◽

Western North Pacific ◽

Shape Parameter ◽

Surface Wind ◽

Japan Meteorological Agency ◽

Wind Structure ◽

Linear Relationships ◽

Wind Analysis ◽

Joint Typhoon Warning Center

Abstract Symmetric and wavenumber-1 asymmetric characteristics of western North Pacific tropical cyclone (TC) outer wind structures are compared between best tracks from the Joint Typhoon Warning Center (JTWC) and the Japan Meteorological Agency (JMA) from 2004 to 2014 as well as the Multiplatform Tropical Cyclone Surface Wind Analysis (MTCSWA) product from 2007 to 2014. Significant linear relationships of averaged wind radii are obtained among datasets, in which both gale-force and storm-force wind radii are generally estimated slightly smaller (much larger) by JTWC (JMA) than by MTCSWA. These correlations are strongly related to TC intensity relationships discussed in earlier work. Moreover, JTWC (JMA) on average represents a smaller (greater) derived shape parameter than MTCSWA does, implying that JTWC (JMA) typically assesses a more compact (less compact) storm than MTCSWA. For the wavenumber-1 asymmetry, large differences among datasets are found regardless of the magnitude or the direction of the longest radius. JTWC estimates more asymmetric storms than JMA, and it provides greater wavenumber-1 asymmetry magnitudes on average. Asymmetric storms are most frequently oriented toward the east, northeast, and north in JTWC and MTCSWA, whereas they are most frequently oriented toward the southeast, east, and northeast in JMA. The direction of the longest gale-force (storm force) wind radius in JTWC is statistically rotated 18° (32°) clockwise to that in JMA. Although the wind radii in JTWC are of higher quality than those in JMA when using MTCSWA as a baseline, there remains a need to provide a consistent and reliable wind radii estimating process among operational centers.

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Evaluation of the Surface Wind Field over Land in WRF Simulations of Hurricane Wilma (2005). Part I: Model Initialization and Simulation Validation

Monthly Weather Review ◽

10.1175/mwr-d-20-0199.1 ◽

2021 ◽

Author(s):

David S. Nolan ◽

Brian D. McNoldy ◽

Jimmy Yunge

Keyword(s):

Wind Field ◽

Urban Areas ◽

Initial Conditions ◽

Surface Wind ◽

South Florida ◽

Wind Fields ◽

Near Surface ◽

Hurricane Wilma ◽

Wind Analysis ◽

Forecasting System

AbstractWhile global and regional dynamical models are used to predict the tracks and intensities of hurricanes over the ocean, these models are not currently used to predict the wind field and other impacts over land. This two-part study performs detailed evaluations of the near-surface, over-land wind fields produced in simulations of Hurricane Wilma (2005) as it traveled across South Florida. This first part describes the production of two high-resolution simulations using the Weather Research and Forecasting Model (WRF), using different boundary layer parameterizations available in WRF: the Mellor-Yamada-Janjić (MYJ) scheme and the Yonsei University (YSU) scheme. Initial conditions from the Global Forecasting System (GFS) are manipulated with a vortex bogussing technique to modify the initial intensity, size, and location of the cyclone. It is found possible through trial and error to successfully produce simulations using both the YSU and MYJ schemes that closely reproduce the track, intensity, and size of Wilma at landfall. For both schemes the storm size and structure also show good agreement with the wind fields diagnosed by H*WIND and the Tropical Cyclone Surface Wind Analysis (TCSWA). Both over water and over land, the YSU scheme has stronger winds over larger areas than MYJ, but the surface winds are more reduced in areas of greater surface roughness, particularly in urban areas. Both schemes produced very similar inflow angles over land and water. The over-land wind fields are examined in more detail in the second part of this study.

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Tropical Cyclone Destructive Potential by Integrated Kinetic Energy

Bulletin of the American Meteorological Society ◽

10.1175/bams-88-4-513 ◽

2007 ◽

Vol 88 (4) ◽

pp. 513-526 ◽

Cited By ~ 156

Author(s):

Mark D. Powell ◽

Timothy A. Reinhold

Keyword(s):

Wind Speed ◽

Tropical Cyclone ◽

Kinetic Energy ◽

Surface Wind ◽

Surface Wind Speed ◽

Wind Loading ◽

Wind Fields ◽

Damage Potential ◽

Spatial Coverage ◽

Destructive Potential

Tropical cyclone damage potential, as currently defined by the Saffir-Simpson scale and the maximum sustained surface wind speed in the storm, fails to consider the area impact of winds likely to force surge and waves or cause particular levels of damage. Integrated kinetic energy represents a framework that captures the physical process of ocean surface stress forcing waves and surge while also taking into account structural wind loading and the spatial coverage of the wind. Integrated kinetic energy was computed from gridded, objectively analyzed surface wind fields of 23 hurricanes representing large and small storms. A wind destructive potential rating was constructed by weighting wind speed threshold contributions to the integrated kinetic energy, based on observed damage in Hurricanes Andrew, Hugo, and Opal. A combined storm surge and wave destructive potential rating was assigned according to the integrated kinetic energy contributed by winds greater than tropical storm force. The ratings are based on the familiar 1–5 range, with continuous fits to allow for storms as weak as 0.1 or as strong as 5.99.

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