HRD 2000 Programs by Subject

The majority of the Hurricane Research Division projects actively address the "Advance Short-term Warning and Forecast Services" element of the NOAA 1995-2005 Strategic Plan. However, our scientists are also involved in important research relating to the "Coastal Ecosystems Health", "Implement Seasonal to Interannual Climate Forecasts", and "Predict and Assess Decadal to Centennial Change" elements.

Tropical Cyclone Research

1. Hurricane Track Forecasting

   SEMISPECTRAL MODELS OF HURRICANE MOTION AND INTENSIFICATION.

   To evaluate the roles of spectral truncation, domain size and baroclinicity in hurricane motion using a semispectral model and, more generally, to evaluate the power of the semispectral vortex tracking (SSVT) formulation to improve physical understanding and modeling of tropical cyclones.

   Prediction of model perfromance

   Provide estimates of model error in operational forecasts of tropical cyclone motion.

   Ensemble forecasting and prediction of model performance

   Evaluation of methods to improve operational forecasts of tropical cyclone motion.

   Adaptive observations to improve hurricane track forecasts

   Target aircraft and dropsonde observations to optimally affect tropical cyclone track forecasts.

   The HRD Synoptic Surveillance Field Experiment : The impact of operational synoptic surveillance on operational hurricane track forecast models

   To evaluate the impact of special environmental observations on the objective hurricane track forecast guidance available to the OAR.

   OBJECTIVE ANALYSIS OF THE HURRICANE AND ITS ENVIRONMENT

   Diagnosis of the structure of the tropical cyclone core and environment; investigation of factors influencing tropical cyclone motion and intensification.

2. Internal Dynamics

   Modeling the hurricane dynamics with explicit moist convection

   Comprehensive understanding of hurricane dynamics with a numerical model that explicitly includes the cloud-scale moist convection interacting with the hurricane environment.

   AN IMPROVED UNDERSTANDING OF LOW-LEVEL THERMODYNAMIC CONDITIONS NEAR THE TROPICAL CYCLONE INNER CORE

   Through observations, obtain an improved physical understanding of air-sea interaction processes and boundary layer thermodynamics within and outside the tropical cyclone (TC) inner core.

   HURRICANE EYE THERMODYNAMICS

   Physical understanding of the eye's role in hurricane intensification.

   Climatological and Synoptic Characteristics of Rapidly Intensifying Tropical Cyclones in the North Atlantic Basin
   

   To investigate rapidly intensifying tropical cyclones as defined for the North Atlantic Basin.

   ARE THE BETA GYRES NORMAL MODES?

   To determine whether the streamfunction dipoles induced by the beta effect on simulated hurricane-like vortices are normal modes or continuous-spectrum solutions.

   Structure of Hurricanes and its Variation as observed by Airborne Doppler Radar

   Describe the various inner core kinematic and reflectivity structures, and their relationships to environmental factors, such as wind shear and sea-surface temperature . Also describe their short-term variation.

   KINEMATIC VELOCITY STRUCTURE OF HURRICANE GILBERT (1988)

   Analyze airborne Doppler radar data collected in Hurricane Gilbert on 14 September 1988, to estimate the axisymmetric components of the three-dimensional windfield of this Category 5 hurricane.

3. Hurricane Precipitation and Electrification

   Development of a TRMM-based Tropical Cyclone Precipitation Climatology

   Use data from the TRMM satellite to estimate tropical rainfall and compare it to ground-truth from the WP-3 aircraft measurements.

   DROP DISTORTIONS NEAR LARGE AIRCRAFT AS OBSERVED BY 2-D PARTICLE PROBE IMAGES

   To determine the cause and extent of the distortion of raindrops around the WP-3D 2-D probe mounts, and to devise means of minimizing and/or compensating for it.

   CLOUD-TO-GROUND LIGHTNING AND TROPICAL CYCLONES

   To identify the location and characteristics of cloud-to-ground (CG) lightning with respect to a hurricane's center, to explain why certain regions of the hurricane are more electrically-active than others, and to determine the universality of past results.

   TROPICAL CYCLONE ELECTRIFICATION STUDIES

   To determine the conditions under which tropical oceanic convection becomes electrified, and to relate that activity to the evolution of the storm circulation.

4. Airborne Hurricane Studies

   Three-Dimensional variational analysis of airborne Doppler observations

   To improve dual- and multiple-Doppler analyses by incorporating the Doppler projection equations, the three-dimensional continuity equation, and filtering within a variational scheme.

   Boundary Layer Measurements in Hurricanes using GPS-sondes : Comparisons with in situ Observations

   HRD began dropping the newly developed NCAR Global Positioning System (GPS) dropwindsondes in the vicinity of Atlantic tropical cyclones. High-resolution vertical profiles of wind speed and direction, temperature, dew point, and pressure were collected from flight-level to the surface. Sondes were dropped near National Data Buoy Center (NDBC) platforms to compare with in situ measurements. Preliminary comparisons have been made between the available mean boundary layer and surface data from profiles in the vicinity of NDBC platforms in tropical cyclones.

   REAL-TIME HURRICANE WIND FIELD ANALYSIS AND DAMAGE MITIGATION

   To develop a real-time hurricane surface wind analysis system for forecast, damage assessment and recovery planning support.

   AIRBORNE HURRICANE ANALYSIS SYSTEMS

   To analyze the relatively large amounts of data collected on board the P-3 aircraft and to transmit key information to forecasters on the ground.

5. Hurricane Winds at Landfall Studies

   WSR-88D observations of hurricane atmospheric boundary layer structure at landfall

   Using data from land-based radar of landfalling hurricanes and intercomparing them with airborne Doppler radar to define the structure of the hurricane boundary layer.

   An Empirical Inland Wind Decay Model for the New England Region

   Use data archived at the Hurricane Research Division (HRD) and the National Climatic Data Center (NCDC) to derive an empirical model for predicting the decrease in tropical cyclone wind speeds after landfall for the New England Region.

   Study of Supertyphoon Paka

   The NOAA Paka Data Acquisition Team of Arthur Chiu, Greg Forbes, and Sam Houston was assembled on Guam soon after Super Typhoon Paka's movement through the Marshall Islands in mid-December 1997. This was the first such group charged with gathering storm related data under the National Post-Storm Data Acquisition Plan. A full report of the findings and recommendations of this team is provided.

   TROPICAL CYCLONE WINDFIELDS AT LANDFALL FROM AIRBORNE AND LAND BASED DOPPLER RADAR DATA

   Analyze the three-dimensional wind structure of landfalling tropical cyclones by combining airborne Doppler radar data collected by NOAA research aircraft with Doppler data archived by National Weather Service WSR-88D coastal radars.

6. Climate Variations

   Seasonal Forecasting of Tropical Cyclones, Tropical Rainfall and the El Nino-Southern Oscillation

   To investigate statistical seasonal forecasting methodologies and to issue real-time seasonal predictions for various tropical meteorology/oceanography phenomena, including Atlantic basin hurricanes, African rainfall and the El Nino/Southern Oscillation phenomena.

   Climate Variability of Tropical Cyclones around the World

   To analyze past tropical cyclone variability and its accompanying climate and to quantify how changes have occurred on the timescales of intra-seasonal, interannual, interdecadal and century ranges.

   EL NIÑO AND ATLANTIC TROPICAL CYCLONES

   Use of objective techniques to better elucidate the role of tropical Pacific SSTs (e.g., ENSO) in Atlantic tropical cyclone fluctuations.

   Other Research Programs and HRD Projects

   1. Technical Evaluations

      EVALUATION OF THE PERFORMANCE OF GPS DROPWINDSONDES

      To evaluate the performance and mesurement errors of the GPS dropwindsondes.

      Satellite Imagery Investigations of Tropical Cyclone Activity

      To help provide satellite imagery both in real-time and for research purposes via the RAMSDIS computer.

   2. Florida Bay

      EPISODIC METEOROLOGICAL EVENTS AFFECTING FLORIDA BAY

      The primary objective of this research project is to reconstruct episodic/catastrophic meteorological events and local weather regimes which critically affect the South Florida ecosystem.

      RECONSTRUCTION OF SURFACE WIND FIELDS FOR TROPICAL CYCLONES AFFECTING FLORIDA BAY

      The primary objective of this research project is to reconstruct episodic/catastrophic meteorological events which critically affect the South Florida ecosystem.

   3. Education

      Hurricanes, Typhoons and Tropical Cyclones Frequently Asked Questions (FAQ)

      To provide informative answers to public/media frequently asked questions on hurricanes via the World Wide Web.

      TROPICAL CYCLONE PUBLIC AWARENESS PROGRAMS: PREPARING FOR THE TWENTY-FIRST CENTURY

      This effort supports the World Meteorological Organization's Tropical Cyclone Programme (TCP). The primary goal of this work is to develop a resource guide, for disaster preparedness officials and educators, for use in creating awareness in tropical-cyclone-prone nations.