|PROGRESS REPORT - February 1, 1999|
Simulations of Regional Climatic Patterns
which Impact the Florida Bay Water Cycle
Dr. Craig A. Mattocks
University of Miami/CIMAS
Hurricane Research Division, NOAA-AOML
4301 Rickenbacker Causeway
Miami, Florida 33149 -USA-
This project directly addresses the first central question articulated in the Strategic Plan of the Interagency Florida Bay Science Program, namely: How, and at what rates, do persistent and/or catastrophic storms alter freshwater input (via their associ
ated local evaporation/precipitation patterns), thereby inducing changes in the circulation and salinity/nutrient content of Florida Bay?
The approach is to use the Center for Analysis and Prediction of Storms' Advanced Regional Prediction System (ARPS) cloud-/mesoscale atmospheric numerical weather prediction model to simulate persistent, locally-forced weather regimes (land/lake/urban hea t island breeze circulations) which generate thunderstorm complexes over the Everglades and coastal areas that provide roughly one-third of Florida's annual rainfall.
|ACCOMPLISHMENTS DURING FY 98:|
|1. January-August, 1998||In the first phase of development of a coupled hydro-meteorological model, the ARPS model grid was completely reconfigured to closely match the grid of the Natural System Model (NSM) and the South Florida Water Management Model (SFWMM). High-resolution GIS soil/vegetation, land cover/use surface characteristics, and terrain elevation data from SFWMD was reprocessed and incorporated into ARPS. This became an extremely labor-intensive, iterative process because numerous processing errors in the datasets (incorrect map projection, erroneous locations, systematic gaps in data values) had to be corrected. Decoding and analysis algorithms were developed (FORTRAN/C source code) and debugged for use with each of these datasets.|
|2. June-August, 1998||While in the process of reconfiguring the ARPS model with 100-meter resolution Defense Mapping Agency (DMA) terrain elevation data, the PI realized from previously published analyses and model sensitivity studies of coastally trapped disturbances (Ralph e t al., 1998; Thompson et al., 1997) that detailed variations in the terrain can have a profound impact on their initiation and mesoscale structure. The PI also realized that the techniques commonly used for numerical terrain generation were designed 15 ye ars ago for global or synoptic-scale simulations (with grid mesh sizes larger than 100 km) and involve processing datasets with relatively coarse (global, 5-minute) resolution. Blindly extending these techniques to high-resolution mesoscale models generat es numerical noise or suppresses key features in simulations. Therefore, a new hybrid technique was developed and employed to produce a superior rendition of the elevation for the ARPS model. Even fine-scale features, such as the coral ridge south of Miam i and the Florida Keys, are now well resolved.|
|3. May 12, 1998||Presented a poster entitled "Simulations of Regional Climatic Patterns which Impact the Florida Bay Water Cycle" at the FL Bay Science Conference in Miami, FL, authored by Dr. Craig Mattocks and SFWMD colleagues Dr. Paul Trimble, Marie Pietrucha, Matt Hin ton and Beheen Trimble.|
|4. May, 1998||Held extensive briefings with superiors in Miami to report on progress with the ARPS model and to request memory/CPU upgrades to computational resources in order run simulations with the newly reconfigured, high-resolution version of ARPS.|
|5. May-July, 1998||Worked with NOAA-AOML's Paul Willis and CAPS/OU atmospheric research scientists to investigate optimizing model-simulated rainfall estimates by tuning the rain drop size distributions to match those of the airborne and ground-based measurements. After num erous discussions and preliminary experiments with a large eddy simulation (LES) model, it was determined that modifying the drop size distributions for rain, cloud ice, snow, and hail/graupel in the Kessler warm rain and Tao & Simpson ice-phase microphys ics, from the oversimplified Marshall-Palmer (1948) inverse-exponential formulation to an analytical gamma curve fit (which normally would improve the accretion/autoconversion and evaporation of drops at the large and small ends of the spectrum) would hav e little impact on model simulations of rainfall because there are more serious deficiencies in the basic assumptions of the ARPS microphysical parameterizations.|
|6. June, 1998||In order to refine the response of the ARPS surface energy budget (Bougeault et al., 1991), developed new categories and parameters for Everglades muck soil and Mangrove forest.|
|7. September, 1998||Wrote a final report entitled "Configuration of a High-Resolution Mesoscale NWP Model for Coastal Simulations" for a $1 million/year research project at CAPS/OU funded by the Office of Naval Research, which involved remote sensing and prediction of the co astal marine boundary layer.|
|8. September, 1998||Collected and archived an extensive set of meteorological observations during Hurricane Georges' traverse over FL Bay and through the Florida Keys. Sustained winds of 90-115 mph, heavy rains and a 7-9 ft storm surge caused significant damage to algae, cor als, sponges and sea urchins at depths from 7-25 feet.|
|9. October, 1998||Updated the atmospheric modeling portion of the Florida Bay web pages at NOAA-AOML to reflect latest results.|
|OBJECTIVES FOR FY 99:|
|1.||Obtain adequate computational resources to run the newly configured high-resolution version of the ARPS model.|
|2.||Convert terrain elevation, soil/vegetation, and land cover/use datasets to binary format in order to initialize and run a sea breeze simulation using the ARPS model. Estimate the total freshwater input from rainfall over the Florida Peninsula. Generate ev aporation estimates from the ARPS surface energy/soil module. Calibrate results against a composite of real measurements.|
|3.||Submit a paper entitled "Development of a Coupled Hydro-Meteorological Model for Florida Everglades Habitat Reconstruction" for publication in Monthly Weather Review.|
|4.||Incorporate a data window filtering algorithm into the two-dimensional Fast Fourier Transform (FFT) technique used to calculate the power spectral density (PSD) of terrain representations in order to diagnose the numerical noise more accurately. Run 2-D n umerical simulations of mountain wave simulations to assess the performance of each terrain representation.|
|5.||Submit a paper entitled "A New Technique for Generating Terrain Representations in High-Resolution Mesoscale NWP Models" for publication in Weather and Forecasting.|
|6.||Process/analyze meteorological data for Hurricane Georges and submit it to Ms. Dawn Welcher for inclusion into the South Florida Ecosystem Restoration Prediction and Modeling Program (SFERPM) database at NOAA-AOML.|
|7.||Collect GriB, surface, upper-air data and surface winds analyses in for a strong cold frontal passage over Florida Bay. Initialize ARPS with non-homogeneous 3-D fields constructed from NMC/NCEP Eta/Meso model forecast fields merged with the collected real data. Conduct ARPS simulations and contrast the predicted wind forcing over Florida Bay from this advective cold front case against the more locally-driven sea breeze case.|
|8.||Update Florida Bay web pages at NOAA-AOML.|
Bougeault, P., B. Bret, P. Lacarrere and J. Noilhan, 1991: An experiment with an advanced surface parameterization in a mesobeta-scale model. Part II: The June 1986 simulation. Monthly Weather Review, 119, 2374-2392.
Ralph, F.M., L. Armi, J.M. Bane, C. Dorman, W.D. Neff, P.J. Neiman, W.Nuss and P.O.G. Persson, 1998: Observations and analysis of the 10-11 June 1994 coastally trapped disturbance. Monthly Weather Review, 126, 2435-2 465.
Thompson, W.T., T. Haack, J.D. Doyle and S.D. Burk, 1997: A nonhydrostatic mesoscale simulation of the 10-11 June 1994 coastally trapped wind reversal. Monthly Weather Review, 125, 3211-3230.