Meteorological Modeling of Hurricanes and Coastal Interactions: A Stability Study For Vertical Pressure Levels

EPA Grant Number: R830651C001
Subproject: this is subproject number 001 , established and managed by the Center Director under grant R827072
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Alabama Center For Estuarine Studies (ACES)
Center Director: Shipp, Robert L.
Title: Meteorological Modeling of Hurricanes and Coastal Interactions: A Stability Study For Vertical Pressure Levels
Investigators: Dougherty, F. Carroll , Kimball, Sytske K.
Institution: University of South Alabama
EPA Project Officer: Packard, Benjamin H
Project Period: November 1, 2002 through October 31, 2006 (Extended to October 31, 2007)
RFA: Targeted Research Center (2006) Recipients Lists
Research Category: Targeted Research

Objective:

A study completed for an idealized hurricane simulation over water at a constant surface temperature showed that the storm developed very differently as a function of the vertical spacing of the model sigma levels. The distribution of vertical levels in the inflow, outflow, and middle layers of the atmosphere clearly affected the intensity, size, and structure of the storms, causing certain processes to be under- or over-resolved. A strong outflow was found to be necessary for proper storm intensification, while a strong inflow layer did not correspond to an intense storm. In fact, when a strong inflow layer was coupled with a weak outflow layer, a particularly weak storm was the result. When too few levels were assigned to the outflow layer, convection was confined to low- and mid-tropospheric levels, and too little latent heating occurred at the middle levels to facilitate the formulation of a strong secondary circulation. However, too few levels in the planetary boundary level would cause a storm to intensify beyond its theoretically calculated maximum potential intensity. Before better guidelines for vertical level distribution could be developed, however, a second study of the sensitivity to vertical sigma levels for more realistic storm simulations was necessary.

This new study will use data from Hurricane Katrina as it made landfall on the Gulf Coast as the test case for varying the distribution of sigma levels in the Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model version 5 (MM5). In the idealized simulation, varying sea surface temperatures and upper level environmental flows were not included, yet they may have an impact of the development of the storm as a function of the sigma level distribution. In addition, the physics parameterizations may also be a function of the number of sigma levels in a particular region. Two sets of sensitivity studies will be addressed. The first will use a fixed number of sigma levels distributed in several different regions. These results will be compared with the trends identified with the idealized results. A second set of simulations will add more levels in certain regions to evaluate the sensitivity of the storm structure and development to the placement of the sigma levels. Both sets of results will be compared with observations and analyzed.

The ultimate goal of these studies is to provide recommendations for an optimal number of sigma levels and their distribution. These results have important implications to hurricane forecasting; models such as MM5 are used operationally to forecast hurricane track and intensity. If such models are sensitive to the distribution and number of vertical levels, then forecasts may not accurately represent the real situation with serious consequences to life and property.

Progress and Final Reports:

  • 2003
  • 2004
  • 2005
  • 2006
  • Final

  • Main Center Abstract and Reports:

    R827072    Alabama Center For Estuarine Studies (ACES)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R827072C001 Fluorescent Whitening Agents As Facile Pollution Markers In Shellfishing Waters
    R827072C002 Red Snapper Demographics on Artificial Reefs: The Effect of Nearest-Neighbor Dynamics
    R827072C003 Stabilization of Eroding Shorelines in Estuarine Wave Eliminates with Constructed Fringe Wetlands Incorporating Offshore Breakwaters
    R827072C004 Interaction Between Water Column Structure and Reproduction in Jellyfish Populations Of Mobile Bay (SGER)
    R827072C005 Effects of Variation in River Discharge and Wind-Driven Resuspension on Higher Trophic Levels in the Mobile Bay Ecosystem
    R827072C006 Results of Zooplankton Component
    R827072C007 Benthic Study Component
    R827072C008 A Preliminary Survey of Macroalgal and Aquatic Plant Distribution in the Mobile Tensaw Delta
    R827072C009 Fisheries-induced changes in the structure and function of shallow water "nursery habitats": an experimental assessment
    R827072C010 Effects Of Variation in River Discharge and Wind-Driven Resuspension on Lower Trophic Levels of the Mobile Bay Ecosystem
    R827072C011 Evaluation of Alabama Estuaries as Developmental Habitat for Juvenile Sea Turtles
    R827072C012 Effects of Salinity Stress on Natural and Anthropogenically-Derived Bacteria in Estuarine Environments
    R827072C013 The Role of Land-Use/Land-Cover and Sub-estuarine Ecosystem Nitrogen Cycling in the Regulation of Nitrogen Delivery to a River Dominated Estuary; Mobile Bay, Alabama
    R827072C014 Environmental Attitudes of Alabama Coastal Residents: Public Opinion Polls and Environmental Policy
    R827072C015 Synthesis and Characterization of an Electrochemical Peptide Nucleic Acid Probe
    R827072C016 Determinants of Small-Scale Variation in the Abundance of the Blue Crab Callinectes Sapidus
    R827072C017 Effects of Estrogen Pollution on the Reproductive Fitness of the Gulf Pipefish, Syngnathus scovelli
    R827072C019 A Model for Genetic Diversity Aquatic Insects of the Mobile/Tensaw River Delta
    R827072C020 Evaluating Trophic Processes as Indicators of Anthropogenic Eutrophication in Coastal Ecosystems: An Exploratory Analysis
    R827072C021 Effects of Anthropogenic Eutrophication on the Magnitude and Trophic Fate of Microphytobenthic Production in Estuaries
    R827072C022 Characteristics of Ship Waves and Wind Waves in Mobile Bay
    R827072C023 Methods Comparison Between Stripping Voltammetry and Plasma Emission Spectroscopy for Metals in Mobile Bay
    R827072C024 Changes in Water Conditions and Sedimentation Rates Associated With Construction of the Mobile Bay Causeway
    R827072C025 Cold-Induced Hibernation of Marine Vibrios in the Gulf of Mexico: A Study of Cell-Cell Communication and Dormancy in Vibrio vulnificus
    R827072C026 Holocene Sedimentary History of Weeks Bay, AL: Human and Natural Impacts on Deposition in a Gulf Coast Estuary
    R827072C027 Shelter Bottlenecks and Self-Regulation in Blue Crab Populations: Assessing the Roles of Nursery Habitats and Juvenile Interactions for Shelter Dependent Organisms
    R827072C028 Predicting Seagrass Survival in Nutrient Enriched Waters: Toward a New View of an Existing Paradigm
    R827072C029 DMSP and its Role as an Antioxidant in the Salt Marsh Macrophyte Spartina alterniflora
    R827072C030 A Preliminary Survey of Aerial and Ground-Dwelling Insects of the Mobile/Tensaw Delta
    R827072C031 Natural Biogeochemical Tags of Striped Mullet, Mugil cephalus, Estuarine Nursery Areas in the North Central Gulf of Mexico
    R827072C032 Resolution of Sedimentation Rates in Impacted Coastal Environments Using 137Cs and 210Pb Markers: Dog River and Fowl River Embayments
    R827072C033 Investigation of the Use of Pulse Amplitude Modulated (PAM) Fluorometry as an Indicator of Submerged Aquatic Vegetation Health in Mobile Bay
    R827072C034 Influence of Invasive Plant Species in Determining Diversity of Aquatic Vegetation in the Mobile-Tensaw Delta
    R827072C035 The Influence of Shallow Water Hydrodynamics on the Importance of Seagrass Detritus in Estuarine Food Webs
    R827072C036 Food Web Interactions, Spatial Subsidies and the Flow of Energy Between the Mobile Bay Delta and Offshore Waters: A SGER Proposal to the Alabama Center for Estuarine Studies
    R830651C001 Meteorological Modeling of Hurricanes and Coastal Interactions: A Stability Study For Vertical Pressure Levels
    R830651C002 Characterization of Glycoprotein Cues Used by the Parasitic Rhizocephalan Barnacle Loxothylacus texanus To Identify Its Blue Crab Host, Callinectes sapidus
    R830651C003 Survey of Diamondback Terrapin Populations in Alabama Estuaries
    R830651C004 An Assessment of Environmental Contaminant Levels in Water and Dragonfly Larvae Tissues from the Mobile/Tensaw Delta