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Author
Deng, J. ; Wu, Z. ; Zhang, M. ; Huang, N.E. ; Wang, S. ; Qiao, F.
Title
Using Holo-Hilbert spectral analysis to quantify the modulation of Dansgaard-Oeschger events by obliquity
Type
$loc['typeJournal Article']
Year
2018
Publication
Quaternary Science Reviews
Abbreviated Journal
Quaternary Science Reviews
Volume
192
Issue
Pages
282-299
Keywords
Pleistocene ; Paleoclimatology ; Greenland ; Antarctica ; Data treatment ; Data analysis ; Dansgaard-oeschger (DO) events ; Obliquity forcing ; Phase preference ; Holo-hilbert spectral analysis ; Amplitude modulation ; EMPIRICAL MODE DECOMPOSITION ; GREENLAND ICE-CORE ; NONSTATIONARY TIME-SERIES ; ABRUPT CLIMATE-CHANGE ; LAST GLACIAL PERIOD ; NORTH-ATLANTIC ; MILLENNIAL-SCALE ; RECORDS ; VARIABILITY ; CYCLE
Abstract
Astronomical forcing (obliquity and precession) has been thought to modulate Dansgaard-Oeschger (DO) events, yet the detailed quantification of such modulations has not been examined. In this study, we apply the novel Holo-Hilbert Spectral Analysis (HHSA) to five polar ice core records, quantifying astronomical forcing's time-varying amplitude modulation of DO events and identifying the preferred obliquity phases for large amplitude modulations. The unique advantages of HHSA over the widely used windowed Fourier spectral analysis for quantifying astronomical forcing's nonlinear modulations of DO events is first demonstrated with a synthetic data that closely resembles DO events recorded in Greenland ice cores (NGRIP, GRIP, and GISP2 cores on GICC05 modelext timescale). The analysis of paleoclimatic proxies show that statistically significantly more frequent DO events, with larger amplitude modulation in the Greenland region, tend to occur in the decreasing phase of obliquity, especially from its mean value to its minimum value. In the eastern Antarctic, although statistically significantly more DO events tend to occur in the decreasing obliquity phase in general, the preferred phase of obliquity for large amplitude modulation on DO events is a segment of the increasing phase near the maximum obliquity, implying that the physical mechanisms of DO events may be different for the two polar regions. Additionally, by using cross-spectrum and magnitude-squared analyses, Greenland DO mode at a timescale of about 1400 years leads the Antarctic DO mode at the same timescale by about 1000 years. (C) 2018 Elsevier Ltd. All rights reserved.
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
0277-3791
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ user @
Serial
971
Permanent link to this record
Author
Devanas, A. ; Stefanova, L.
Title
Statistical Prediction Of Waterspout Probability For The Florida Keys
Type
$loc['typeJournal Article']
Year
2018
Publication
Weather and Forecasting
Abbreviated Journal
Wea. Forecasting
Volume
33
Issue
Pages
389-410
Keywords
Regression analysis ; Forecast verification/skill ; Forecasting techniques ; Probability forecasts/models/distribution ; Statistical forecasting
Abstract
A statistical model of waterspout probability was developed for wet-season (June–September) days over the Florida Keys. An analysis was performed on over 200 separate variables derived from Key West 1200 UTC daily wet-season soundings during the period 2006–14. These variables were separated into two subsets: days on which a waterspout was reported anywhere in the Florida Keys coastal waters and days on which no waterspouts were reported. Days on which waterspouts were reported were determined from the National Weather Service (NWS) Key West local storm reports. The sounding at Key West was used for this analysis since it was assumed to be representative of the atmospheric environment over the area evaluated in this study. The probability of a waterspout report day was modeled using multiple logistic regression with selected predictors obtained from the sounding variables. The final model containing eight separate variables was validated using repeated fivefold cross validation, and its performance was compared to that of an existing waterspout index used as a benchmark. The performance of the model was further validated in forecast mode using an independent verification wet-season dataset from 2015–16 that was not used to define or train the model. The eight-predictor model was found to produce a probability forecast with robust skill relative to climatology and superior to the benchmark waterspout index in both the cross validation and in the independent verification.
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Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
0882-8156
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
553
Permanent link to this record
Author
DiNapoli, S
Title
Determining the Error Characteristics of H*WIND
Type
$loc['typeManuscript']
Year
2010
Publication
Abbreviated Journal
Volume
Issue
Pages
Keywords
Hurricane, Tropical Cyclones, Wind Analysis, Uncertainty
Abstract
The HRD Real-time Hurricane Wind Analysis System (H*Wind) is a software application used by NOAA's Hurricane Research Division to create a gridded tropical cyclone wind analysis based on a wide range of observations. One application of H*Wind fields is calibration of scatterometers for high wind speed environments. Unfortunately, the accuracy of the H*Wind product has not been studied extensively, and therefore the accuracy of scatterometer calibrations in these environments is also unknown. This investigation seeks to determine the uncertainty in the H*Wind product and estimate the contributions of several potential error sources. These error sources include random observation errors, relative bias between different data types, temporal drift resulting from combining non-simultaneous measurements, and smoothing and interpolation errors in the H*Wind software. The effects of relative bias between different data types and random observation errors are determined by performing statistical calculations on the observed wind speeds. We show that in the absence of large biases, the total contribution of all error sources results in an uncertainty of approximately 7% near the storm center, which increases to nearly 15% near the tropical storm force wind radius. The H*Wind analysis algorithm is found to introduce a positive bias to the wind speeds near the storm center, where the analyzed wind speeds are enhanced to match the highest observations. In addition, spectral analyses are performed to ensure that the filter wavelength of the final analysis product matches user specifications. With increased knowledge of these error sources and their effects, researchers will have a better understanding of the uncertainty in the H*Wind product, and can then judge the suitability of H*Wind for various research applications
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
574
Permanent link to this record
Author
Domingues, R. ; Kuwano-Yoshida, A. ; Chardon-Maldonado, P. ; Todd, R.E. ; Halliwell, G. ; Kim, H.-S. ; Lin, I.-I. ; Sato, K. ; Narazaki, T. ; Shay, L.K. ; Miles, T. ; Glenn, S. ; Zhang, J.A. ; Jayne, S.R. ; Centurioni, L. ; Le Hénaff, M. ; Foltz, G.R. ; Bringas, F. ; Ali, M.M. ; DiMarco, S.F. ; Hosoda, S. ; Fukuoka, T. ; LaCour, B. ; Mehra, A. ; Sanabia, E.R. ; Gyakum, J.R. ; Dong, J. ; Knaff, J.A. ; Goni, G.
Title
Ocean Observations in Support of Studies and Forecasts of Tropical and Extratropical Cyclones
Type
$loc['typeJournal Article']
Year
2019
Publication
Frontiers in Marine Science
Abbreviated Journal
Front. Mar. Sci.
Volume
6
Issue
Pages
446
Keywords
Abstract
Over the past decade, measurements from the climate-oriented ocean observing system have been key to advancing the understanding of extreme weather events that originate and intensify over the ocean, such as tropical cyclones (TCs) and extratropical bomb cyclones (ECs). In order to foster further advancements to predict and better understand these extreme weather events, a need for a dedicated observing system component specifically to support studies and forecasts of TCs and ECs has been identified, but such a system has not yet been implemented. New technologies, pilot networks, targeted deployments of instruments, and state-of-the art coupled numerical models have enabled advances in research and forecast capabilities and illustrate a potential framework for future development. Here, applications and key results made possible by the different ocean observing efforts in support of studies and forecasts of TCs and ECs, as well as recent advances in observing technologies and strategies are reviewed. Then a vision and specific recommendations for the next decade are discussed.
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Corporate Author
Thesis
Publisher
Place of Publication
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Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
2296-7745
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ user @
Serial
1043
Permanent link to this record
Author
Dukhovskoy, D. S. ; Morey, S. L. ; O'Brien, J. J.
Title
Baroclinic topographic waves on the Nicaragua Shelf generated by tropical cyclones
Type
$loc['typeReport']
Year
2006
Publication
Abbreviated Journal
Volume
Issue
Pages
Keywords
Abstract
Address
Corporate Author
Thesis
Publisher
World Meteorological Organization
Place of Publication
Geneva, Switzerland
Editor
Cote, J.
Language
Summary Language
Original Title
Series Editor
Series Title
Research Activities in Atmospheric and Ocean Modeling, Report No. 36
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
ISBN
Medium
Area
Expedition
Conference
Funding
ONR, NASA
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
924
Permanent link to this record
Author
Dukhovskoy, D. S. ; Morey, S. L. ; O'Brien, J. J.
Title
Topographic Rossby Waves in a Z-Level Ocean Model
Type
$loc['typeReport']
Year
2005
Publication
Abbreviated Journal
Volume
Issue
Pages
03.05-03.06
Keywords
Abstract
Address
Corporate Author
Thesis
Publisher
World Meteorological Organization
Place of Publication
Geneva, Switzerland
Editor
Cote, J.
Language
Summary Language
Original Title
Series Editor
Series Title
Research Activities in Atmospheric and Ocean Modeling, Report No. 35
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
ISBN
Medium
Area
Expedition
Conference
Funding
ONR, NASA
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
903
Permanent link to this record
Author
Dukhovskoy, D. S. ; Morey, S. L. ; O'Brien, J. J.
Title
Topographic Rossby waves in a z-level ocean model
Type
$loc['typeMagazine Article']
Year
2005
Publication
Eos Trans. AGU
Abbreviated Journal
Volume
86
Issue
18
Pages
Jt. Assem. Suppl., Abstract OS22A-06
Keywords
Abstract
Address
Corporate Author
Thesis
Publisher
Place of Publication
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
ONR, NASA
Approved
$loc['no']
Call Number
COAPS @ mfield @
Serial
909
Permanent link to this record
Author
Dukhovskoy, D.S. ; Yashayaev, I. ; Proshutinsky, A. ; Bamber, J.L. ; Bashmachnikov, I.L. ; Chassignet, E.P. ; Lee, C.M. ; Tedstone, A.J.
Title
Role of Greenland Freshwater Anomaly in the Recent Freshening of the Subpolar North Atlantic
Type
$loc['typeJournal Article']
Year
2019
Publication
Journal of Geophysical Research: Oceans
Abbreviated Journal
J. Geophys. Res. Oceans
Volume
124
Issue
5
Pages
3333-3360
Keywords
Greenland ice sheet melting ; freshwater anomaly ; subpolar North Atlantic ; subpolar gyre ; passive tracer numerical experiment ; freshwater budget
Abstract
The cumulative Greenland freshwater flux anomaly has exceeded 5000 km3 since the 1990s. The volume of this surplus fresh water is expected to cause substantial freshening in the North Atlantic. Analysis of hydrographic observations in the subpolar seas reveal freshening signals in the 2010s. The sources of this freshening are yet to be determined. In this study, the relationship between the surplus Greenland freshwater flux and this freshening is tested by analyzing the propagation of the Greenland freshwater anomaly and its impact on salinity in the subpolar North Atlantic based on observational data and numerical experiments with and without the Greenland runoff. A passive tracer is continuously released during the simulations at freshwater sources along the coast of Greenland to track the Greenland freshwater anomaly. Tracer budget analysis shows that 44% of the volume of the Greenland freshwater anomaly is retained in the subpolar North Atlantic by the end of the simulation. This volume is sufficient to cause strong freshening in the subpolar seas if it stays in the upper 50�100 m. However, in the model the anomaly is mixed down to several hundred meters of the water column resulting in smaller magnitudes of freshening compared to the observations. Therefore, the simulations suggest that the accelerated Greenland melting would not be sufficient to cause the observed freshening in the subpolar seas and other sources of fresh water have contributed to the freshening. Impacts on salinity in the subpolar seas of the freshwater transport through Fram Strait and precipitation are discussed.
Address
Corporate Author
Thesis
Publisher
Place of Publication
Editor
Language
Summary Language
Original Title
Series Editor
Series Title
Abbreviated Series Title
Series Volume
Series Issue
Edition
ISSN
2169-9275
ISBN
Medium
Area
Expedition
Conference
Funding
Approved
$loc['no']
Call Number
COAPS @ user @
Serial
1029
Permanent link to this record
Author
Engelman, M. B.
Title
A Validation of the FSU/COAPS Climate Model
Type
$loc['typeManuscript']
Year
2008
Publication
Abbreviated Journal
Volume
Issue
Pages
Keywords
Crop Models, Skill Scores, Seasonal Prediction, Extreme Events
Abstract
This study examines the predictability of the Florida State University/Center for Oceanic and Atmospheric Prediction Studies (FSU/COAPS) climate model, and is motivated by the model's potential use in crop modeling. The study also compares real-time ensemble runs (created using persisted SST anomalies) to hindcast ensemble runs (created using weekly updated SST) to asses the effect of SST anomalies on forecast error. Wintertime (DJF, 2 month lead time) surface temperature and precipitation forecasts over the southeastern United States (Georgia, Alabama, and Florida) are evaluated because of the documented links between tropical Pacific SST anomalies and climate in the southeastern United States during the winter season. The global spectral model (GSM) runs at a T63 resolution and then is dynamically downscaled to a 20 x 20 km grid over the southeastern United States using the FSU regional spectral model (RSM). Seasonal, monthly, and daily events from the October 2004 and 2005 model runs are assessed. Seasonal (DJF) plots of real-time forecasts indicate the model is capable of predicting wintertime maximum and minimum temperatures over the southeastern United States. The October 2004 and 2005 real-time model runs both produce temperature forecasts with anomaly errors below 3°C, correlations close to one, and standard deviations similar to observations. Real-time precipitation forecasts are inconsistent. Error in the percent of normal precipitation vary from greater than 100% in the 2004/2005 forecasts to less than 35% error in the 2005/2006 forecasts. Comparing hindcast runs to real-time runs reveals some skill is lost in precipitation forecasts when using a method of SST anomaly persistence if the SST anomalies in the equatorial Pacific change early in the forecast period, as they did for the October 2004 model runs. Further analysis involving monthly and daily model data as well as Brier scores (BS), relative operating characteristics (ROC), and equitable threat scores (ETS), are also examined to confirm these results.
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
607
Permanent link to this record
Author
Enloe, J.
Title
ENSO impacts on peak wind gusts in the United States
Type
$loc['typeManuscript']
Year
2002
Publication
Abbreviated Journal
Volume
Issue
Pages
Keywords
Abstract
Address
Department of Meteorology
Corporate Author
Thesis
$loc['Master's thesis']
Publisher
Place of Publication
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
629
Permanent link to this record