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| Author | Scott, JP | ||||
| Title | An Intercomparison of Numerically Modeled Flux Data and Satellite-Derived Flux Data for Warm Seclusions | Type | $loc['typeManuscript'] | ||
| Year | 2011 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Satellite; Reanalysis; Air Sea Interaction; Turbulent Heat Fluxes; Intercomparison; Warm Seclusion | ||||
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| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | Approved | $loc['no'] | |||
| Call Number | COAPS @ mfield @ | Serial | 335 | ||
| Permanent link to this record | |||||
| Author | Taylor, J. P. | ||||
| Title | Comparison of ECMWF and Quikscat-Derived Surface Pressure Gradients | Type | $loc['typeManuscript'] | ||
| Year | 2006 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Flagging Techniques | ||||
| Abstract | A technique based solely on QuikSCAT data is developed for determining suspect differences between QSCAT and ECMWF pressure gradients. Pressure fields are computed from scatterometer winds using a variational method that applies a gradient wind conversion. Kinematic analysis of the satellite wind field is performed in order to determine which parameters are physically related to the suspect pressure gradients. It is discovered that the likelihood of these suspect occurrences has the greatest dependence on relative vorticity, total deformation, and the curvature Rossby number. A broad range of these values is tested and a single assessment criterion is derived based upon the value of several skill scores. Overall, the assessment criterion is able to correctly identify the majority of suspect pressure gradients; yet considerable over-flagging does occur in many instances. However, the over-flagging is not random: the false alarms are tightly clustered around the suspect areas, resulting in flagged regions that are too large. Identification of the location of suspect areas in pressure products should be useful to forecasters. | ||||
| Address | Department of Meteorology | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | NASA, OVWST, SeaWinds | Approved | $loc['no'] | ||
| Call Number | COAPS @ mfield @ | Serial | 619 | ||
| Permanent link to this record | |||||
| Author | Strazzo, S | ||||
| Title | Low-Frequency Minimum Temperature Variability Throughout the Southeastern United States during the 1970s: Regime Shift or Phase Coincidence? | Type | $loc['typeManuscript'] | ||
| Year | 2011 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Low-frequency variability; Climate variability; Climate regime | ||||
| Abstract | |||||
| Address | Department of Earth Ocean and Atmospheric Science | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | Approved | $loc['no'] | |||
| Call Number | COAPS @ mfield @ | Serial | 336 | ||
| Permanent link to this record | |||||
| Author | Stroman, A | ||||
| Title | The Rendition of the Atlantic Warm Pool in Reanalyses | Type | $loc['typeManuscript'] | ||
| Year | 2011 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Wang; lead-lag; Contemporaneously; Correlations; Tendency | ||||
| Abstract | |||||
| Address | Department of Earth, Ocean and Atmospheric Science | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | Approved | $loc['no'] | |||
| Call Number | COAPS @ mfield @ | Serial | 337 | ||
| Permanent link to this record | |||||
| Author | Lombardi, K. C. | ||||
| Title | Resolving the Diurnal and Synoptic Variance of Scatterometer Vector Wind Observations | Type | $loc['typeManuscript'] | ||
| Year | 2004 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Rotary Spectra, Least Squares Regression, QSCAT, Midori2, Oceanic Winds | ||||
| Abstract | Scatterometer observations of vector winds are used to examine the amplitudes of synoptic and diurnal cycles. Scatterometers have the advantage of providing global coverage over water; however, irregular temporal sampling complicates the analyses. A least squares technique is used in determination of the amplitudes and phases of the diurnal and synoptic cycles on spatial scales of 5°, 15°, and 30°. In open ocean areas and regions with sufficient open water, the magnitudes of the diurnal and synoptic cycles are 1.0 ms-1 and 3.5ms-1, respectively. Diurnal amplitudes are highest in the polar regions and close to land surfaces due to sea breeze effects. The fraction of variance explained by the diurnal cycle is greatest near the equator. Synoptic amplitudes are consistently larger downwind of land from storm tracks and in the southern polar region as the time analyzed is during the southern winter season. | ||||
| Address | Department of Meteorology | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | NASA, OSU | Approved | $loc['no'] | ||
| Call Number | COAPS @ mfield @ | Serial | 624 | ||
| Permanent link to this record | |||||
| Author | Banks, R. | ||||
| Title | Variability of Indian Ocean Surface Fluxes Using a New Objective Method | Type | $loc['typeManuscript'] | ||
| Year | 2006 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Indian Ocean Dipole Mode, Indian Ocean, Objective Method, Surface Turbulent Fluxes, Monsoon, Gridded Product | ||||
| Abstract | A new objective technique is used to analyze monthly mean gridded fields of air and sea temperature, scalar and vector wind, specific humidity, sensible and latent heat flux, and wind stress over the Indian Ocean. A variational method produces a 1°x1° gridded product of surface turbulent fluxes and the variables needed to calculate these fluxes. The surface turbulent fluxes are forced to be physically consistent with the other variables. The variational method incorporates a state of the art flux model, which should reduce regional biases in heat and moisture fluxes. The time period is January 1982 to December 2003. The wind vectors are validated through comparison to monthly scatterometer winds. Empirical orthogonal function (EOF) analyses of the annual cycle emphasize significant modes of variability in the Indian Ocean. The dominant monsoon reversal and its connection with the southeast trades are linked in eigenmodes one and two of the surface fluxes. The third eigenmode of latent and sensible heat flux reveal a structure similar to the Indian Ocean Dipole (IOD) mode. The variability in surface fluxes associated with the monsoons and IOD are discussed. September-October-November composites of the surface fluxes during the 1997 positive IOD event and the 1983 negative IOD event are examined. The composites illustrate characteristics of fluxes during different IOD phases. | ||||
| Address | Department of Meteorology | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | NASA, OSU, NOAA, NSF | Approved | $loc['no'] | ||
| Call Number | COAPS @ mfield @ | Serial | 621 | ||
| Permanent link to this record | |||||
| Author | Lowry, M. R. | ||||
| Title | Developing a Unified Superset in Quantifying Ambiguities Among Tropical Cyclone Best Track Data for the Western North Pacific | Type | $loc['typeManuscript'] | ||
| Year | 2009 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | |||||
| Abstract | In the western North Pacific basin, several agencies archive “best track” data of tropical cyclones. The Joint Typhoon Warning Center (JTWC) in Hawaii is responsible for the issuance of tropical cyclone warnings for United States Department of Defense interests and has a record of tropical cyclones extending back to 1945. The Japanese Meteorological Agency (JMA) is the World Meteorological Organization (WMO) official Regional Specialized Meteorological Center (RSMC) for the western North Pacific basin and has best track tropical cyclone data extending back to 1951. The Shanghai Typhoon Institute (STI) of the Chinese Meteorological Administration and the Hong Kong Observatory (HKO) of the Government of the Hong Kong Special Administrative Region also have 6-hourly tropical cyclone data records from 1949 and 1961, respectively. Western North Pacific (WNP) data sets are investigated in order to quantify ambiguities in position and intensity estimates among the forecast institutions through the development of a unified Superset. Ambiguities among the two primary warning centers (JMA and JTWC) are presented in the context of a changing observation network, observational tools, and analysis techniques since the beginning of tropical cyclone records. Mean differences in position estimates are found between the two centers on the order of 60 km prior to the introduction of meteorological satellites in 1961 and near 50 km following the deactivation of aircraft reconnaissance in 1987. Results show a step function change among intensity in JTWC and JMA best track data from 1989 to 1990 due to varying applications of the Dvorak intensity estimation technique. Parsing best track data into landfall subsets does not ameliorate interagency differences in position or intensity estimates. Additionally, analyses from Superset data call into question the veracity of JTWC best track data during the period from 1995-1999. The applicability of adopting an individual data set in discerning long term climate trends is examined in light of these differences. Past efforts to analyze, assemble, and maintain a complete, reliable best track tropical cyclone data set for the WNP are discussed among topical methods of incorporating the Superset within a basin-wide re-analysis. | ||||
| Address | Department of Meteorology | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | Approved | $loc['no'] | |||
| Call Number | COAPS @ mfield @ | Serial | 605 | ||
| Permanent link to this record | |||||
| Author | Williams, M | ||||
| Title | Characterizing Multi-Decadal Temperature Variability in the Southeastern United States | Type | $loc['typeManuscript'] | ||
| Year | 2010 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Meteorology, Climate Variability, Climate, Warm Regime, Cold Regim | ||||
| Abstract | Prior studies of the long-term temperature record in the Southeastern United States (SE US) mostly discuss the long-term cooling trend, and the inter-annual variability produced by the region's strong ties to El Niño Southern Oscillation (ENSO). An examination of long-term temperature records in the SE US show clear multi-decadal variations in temperature, with relative warm periods in the 1920's through the mid 1950's and a cool period in the late 1950's through the late 1990's. This substantial shift in multi-decadal variability is not well understood and has not been fully investigated. It appears to account for the long-term downward trend in temperatures. An accurate characterization of this variability could lead to improved interannual and long-term forecasts, which would be useful for agricultural planning, drought mitigation, water management, and preparation for extreme temperature events. Statistical methods are employed to determine the spatial coherence of the observed variability on seasonal time scales. The goal of this study is to characterize the nature of this variability through the analysis of National Weather Service Cooperative Observer Program (COOP) station data in Florida, Georgia, Alabama, North Carolina, and South Carolina. One finding is a shift in the temperature Probability Distribution Function (PDF) between warm regimes and cool regimes. | ||||
| Address | Department of Earth Ocean and Atmospheric Science | ||||
| Corporate Author | Thesis | $loc['Master's thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Medium | |||
| Area | Expedition | Conference | |||
| Funding | Approved | $loc['no'] | |||
| Call Number | COAPS @ mfield @ | Serial | 578 | ||
| Permanent link to this record | |||||
| Author | Winterbottom, H | ||||
| Title | The Development of a High-Resolution Coupled Atmosphere-Ocean Model and Applications Toward Understanding the Limiting Factors for Tropical Cyclone Intensity Prediction | Type | $loc['typeManuscript'] | ||
| Year | 2010 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Tropical cyclone vortex initialization, Coupled atmosphere-ocean model | ||||
| Abstract | The prediction of tropical cyclone (TC) motion has improved greatly in recent decades. However, similar trends remain absent with respect to TC intensity prediction. Several hypotheses have been proposed attempting to explain why dynamical NWP models struggle to predict TC intensity. The leading candidates are as follows: (1) the lack of an evolving ocean (i.e., sea-surface temperature) boundary condition which responds as a function of the atmosphere (e.g., TC) forcing, (2) inappropriate initial conditions for the TC vortex (e.g., lack of data assimilation methods), (3) NWP model grid-length resolutions which are unable to resolve the temporal and length scale for the features believed responsible for TC vortex intensity. modulations (i.e., eye-wall dynamics, momentum transport, vortex Rossby wave interactions, etc.), and (4) physical parametrization which do not adequately represent the air-sea interactions observed during TC passage. In this study, a coupling algorithm for two independent, high-resolution, and state-of-the-art atmosphere and ocean models is developed. The atmosphere model -- the Advanced Weather Research and Forecasting (WRF-ARW) model is coupled to the HYbrid Coordinate Ocean Model (HYCOM) using a (UNIX) platform independent and innovative coupling methodology. Further, within the WRF-ARW framework, a dynamic initialization algorithm is developed to specify the TC vortex initial condition while preserving the synoptic-scale environment. Each of the tools developed in this study is implemented for a selected case-study: TC Bertha (2008) and TC Gustav (2008) for the coupled-model and TC vortex initialization, respectively. The experiment results suggest that the successful prediction (with respect to the observations) for both the ocean response and the TC intensity cannot be achieved by simply incorporating (i.e., coupling) an ocean model and/or by improving the initial structure for the TC. Rather the physical parametrization governing the air-sea interactions is suggested as the one of the weaknesses for the NWP model. This hypothesis is (indirectly) supported through a diagnostic evaluation of the synoptic-scale features (e.g., sea-level pressure and the deep-layer mean wind beyond the influence of the TC) while the assimilated TC vortex is nudged toward the observed intensity value. It is found -- in the case of TC Gustav (2008) using WRF-ARW, that as the assimilated TC vortex intensity approaches that of the observed, the balance between the mass and momentum states for WRF-ARW is compromised leading to unrealistic features for the environmental sea-level pressure and deep-layer (800- to 200-hPa) mean wind surrounding the TC. Forcing WRF-ARW to assimilate a TC vortex of the observed maximum wind-speed intensity may ultimately compromise the prediction for the TC's motion and subsequently mitigate any gains for the corresponding intensity prediction.Suggestions for additions to the coupled atmosphere-ocean model include a wave-model (WAVEWATCH3), the assimilation of troposphere thermodynamic observations, and modifications to the existing atmospheric boundary-layer parametrization. The current suite of atmosphere model parametrizations do not accurately simulate the observed azimuthal and radial variations for the exchange coefficients (e.g., drag and enthalpy) that have been indicated as potentialpredictor variables for TC intensity modulation. However, these modifications should be implemented only after the limitations for the current coupled-model and TC vortex initialization methods are fully evaluated. | ||||
| Address | Department of Meteorology | ||||
| Corporate Author | Thesis | $loc['Ph.D. thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
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| Area | Expedition | Conference | |||
| Funding | Approved | $loc['no'] | |||
| Call Number | COAPS @ mfield @ | Serial | 572 | ||
| Permanent link to this record | |||||
| Author | Yu, P | ||||
| Title | Development of New Techniques for Assimilating Satellite Altimetry Data into Ocean Models | Type | $loc['typeManuscript'] | ||
| Year | 2006 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Data Assimilation, Reduced Space, First Baroclinic Mode, Ocean Models, Vertical Normal Mode Decomposition, Variational | ||||
| Abstract | State of the art fully three-dimensional ocean models are very computationally expensive and their adjoints are even more resource intensive. However, many features of interest are approximated by the first baroclinic mode over much of the ocean, especially in the lower and mid latitude regions. Based on this dynamical feature, a new type of data assimilation scheme to assimilate sea surface height (SSH) data, a reduced-space adjoint technique, is developed and implemented with a three-dimensional model using vertical normal mode decomposition. The technique is tested with the Navy Coastal Ocean Model (NCOM) configured to simulate the Gulf of Mexico. The assimilation procedure works by minimizing the cost function, which generalizes the misfit between the observations and their counterpart model variables. The “forward” model is integrated for the period during which the data are assimilated. Vertical normal mode decomposition retrieves the first baroclinic mode, and the data misfit between the model outputs and observations is calculated. Adjoint equations based on a one-active-layer reduced gravity model, which approximates the first baroclinic mode, are integrated backward in time to get the gradient of the cost function with respect to the control variables (velocity and SSH of the first baroclinic mode). The gradient is input to an optimization algorithm (the limited memory Broyden-Fletcher-Goldfarb-Shanno (BFGS) method is used for the cases presented here) to determine the new first baroclinic mode velocity and SSH fields, which are used to update the forward model variables at the initial time. Two main issues in the area of ocean data assimilation are addressed: 1. How can information provided only at the sea surface be transferred dynamically into deep layers? 2. How can information provided only locally, in limited oceanic regions, be horizontally transferred to ocean areas far away from the data-dense regions, but dynamically connected to it? The first problem is solved by the use of vertical normal mode decomposition, through which the vertical dependence of model variables is obtained. Analyses show that the first baroclinic mode SSH represents the full SSH field very closely in the model test domain, with a correlation of 93% in one of the experiments. One common way to solve the second issue is to lengthen the assimilation window in order to allow the dynamic model to propagate information to the data-sparse regions. However, this dramatically increases the computational cost, since many oceanic features move very slowly. An alternative solution to this is developed using a mapping method based on complex empirical orthogonal functions (EOF), which utilizes data from a much longer period than the assimilation cycle and deals with the information in space and time simultaneously. This method is applied to map satellite altimeter data from the ground track observation locations and times onto a regular spatial and temporal grid. Three different experiments are designed for testing the assimilation technique: two experiments assimilate SSH data produced from a model run to evaluate the method, and in the last experiment the technique is applied to TOPEX/Poseidon and Jason-1 altimeter data. The assimilation procedure converges in all experiments and reduces the error in the model fields. Since the adjoint, or “backward”, model is two-dimensional, the method is much more computationally efficient than if it were to use a fully three-dimensional backward model. | ||||
| Address | Department of Oceanography | ||||
| Corporate Author | Thesis | $loc['Ph.D. thesis'] | |||
| Publisher | Florida State University | Place of Publication | Tallahassee, FL | Editor | |
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
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| Area | Expedition | Conference | |||
| Funding | NSF, ONR, NASA | Approved | $loc['no'] | ||
| Call Number | COAPS @ mfield @ | Serial | 589 | ||
| Permanent link to this record | |||||
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