Dr. Daniel Holdaway

Dr. Daniel Holdaway

  • RESEARCH ASSOCIATE
  • 301.614.6158
  • NASA/GSFC
  • Mail Code: 610.1
  • Greenbelt , MD 20771
  • Employer: UNIVERSITIES SPACE RESEARCH ASSOCIATION
  • Brief Bio

    Daniel Holdaway joined NASA's Global Modeling and Assimilation Office in February 2011. Since then he has worked in the atmospheric data assimilation group and specializes in the development of the tangent linear and adjoint versions of GEOS-5. He has developed linearizations of the non-hydrostatic FV3 cubed sphere dynamical core and the convection, cloud, radiation, aerosol and boundary layer schemes. The adjoint of GEOS-5 is one of the most capable in the World and is used for a number of research and operational applications by GMAO and external collaborators.

    Daniel is interested in using the adjoint of GEOS-5 for a number of research applications, especially investigating how initial condition errors can impact forecasts of tropical cyclones and hurricanes. Using the adjoint he has looked at how Saharan dust can impact developing storms and how small scale errors can impact track. He has also used the adjoint to investigate the causes of sudden stratospheric warming. 
     

    Positions/Employment

    12/2013 - Present

    Scientist II

    University Space Research Association, Greenbelt, MD
    2/2011 - 12/2013

    Scientist I

    University Space Research Association, Greenbelt, MD
    10/2010 - 2/2011

    Postdoctoral Researcher

    Exeter University and Tradewind Turbines, Exeter, United Kingdom

    Computational Fluid Dynamics (CFD) of local wind flow with a view to optimal wind turbine positioning. In this position I generated a high resolution computational mesh for an area of land in South West England obtained from GIS data. I then simulated the localized wind speeds for a selection of prevailing wind directions using a Large Eddy Simulation (LES) in OpenFOAM. From the results we were able to determine the most efficient spots to position a portable wind turbine. I also converted CAD specifications of a vertical axis wind turbine into a computational mesh and simulated the stresses experienced by the turbine for a range of different wind speeds. Results from these experiments were used to help asses optimal sail trim.

    Education

    Degree of Ph.D. in Mathematics. Exeter University, 2010. “Coupling Large Scale Dynamics to the Planetary Boundary Layer: Impact of Vertical Discretisation”. Advised by Professor John Thuburn and Dr. Nigel Wood.

    Degree of M.Sc. in Computational Science and Modelling. Exeter University, 2006. Awarded with Distinction (First Class, 4.0 GPA equivlaent).

    Degree of B.Sc. in Mathematics. Exeter University, 2005. Awarded with upper second class honours, 2:1.

    Professional Societies

    American Meteorological Society, 2011 - Present
    American Geophysical Union, 2011 - Present
    Royal Meteorological Society (Student Member), 2006 - 2010

    Other Professional Information

    ORCID identity: orcid.org/0000-0002-3672-2588

    ResearcherID: http://www.researcherid.com/rid/Q-5198-2016

    ResearchGate: https://www.researchgate.net/profile/Daniel_Holdaway

    LinkedIn: https://www.linkedin.com/in/daniel-holdaway-7a65bb60

    H-index: 4 (as of 11/16/2016)

    Publications

    Refereed

    Holdaway, D., and Y. Yang. 2016. "Study of the Effect of Temporal Sampling Frequency on DSCOVR Observations Using the GEOS-5 Nature Run Results (Part I): Earth’s Radiation Budget." Remote Sens., 8 (2): 98 [10.3390/rs8020098]

    Holdaway, D., and Y. Yang. 2016. "Study of the Effect of Temporal Sampling Frequency on DSCOVR Observations Using the GEOS-5 Nature Run Results (Part II): Cloud Coverage." Remote Sensing, 8 (5): [10.3390/rs8050431]

    Holdaway, D. R., and J. Kent. 2015. "Assessing the tangent linear behaviour of common tracer transport schemes and their use in a linearised atmospheric general circulation model ." Tellus A, 67: 27895 [10.3402/tellusa.v67.27895]

    Holdaway, D., R. M. Errico, R. Gelaro, J. G. Kim, and R. B. Mahajan. 2015. "A Linearized Prognostic Cloud Scheme in NASA’s Goddard Earth Observing System Data Assimilation Tools." Monthly Weather Review, 143 (10): 4198-4219 [10.1175/MWR-D-15-0037.1]

    Holdaway, D. R., and R. M. Errico. 2014. "Using Jacobian sensitivities to assess a linearization of the relaxed Arakawa-Schubert convection scheme." Q.J.R. Meteorol. Soc., 140 (681): 1319-1332 [10.1002/qj.2210]

    Holdaway, D. R., R. M. Errico, R. Gelaro, and J. G. Kim. 2014. "Inclusion of Linearized Moist Physics in NASA’s Goddard Earth Observing System Data Assimilation Tools." Mon. Weather Rev., 142 (1): 414-433 [10.1175/MWR-D-13-00193.1]

    Holdaway, D. R., J. Thuburn, and N. Wood. 2013. "Comparison of Lorenz and Charney–Phillips vertical discretisations for dynamics–boundary layer coupling. Part II: Transients." Quarterly Journal of the Royal Meteorological Society, 139 (673): 1087–1098 [10.1002/qj.2017]

    Holdaway, D. R., J. Thuburn, and N. Wood. 2013. "Comparison of Lorenz and Charney–Phillips vertical discretisations for dynamics–boundary layer coupling. Part I: Steady states." Quarterly Journal of the Royal Meteorological Society, 139 (673): 1073-1086 [10.1002/qj.2016]

    Holdaway, D. R., J. Thuburn, and N. Wood. 2007. "On the relation between order of accuracy, convergence rate and spectral slope for linear numerical methods applied to multiscale problems." International Journal for Numerical Methods in Fluids, 56 (8): 1297-1303 [10.1002/fld.1644]

    Talks, Presentations and Posters

    Invited

     GE Whitney Symposium

    10 / 12 / 2015
    •  Data assimilation and observation analysis for numerical weather prediction at NASA

     JCSDA Summer Colloquium

    8 / 4 / 2015
    •  Presented lecture on "Adjoint Model Basics"

    Other

    AGU Fall Meeting 2016

    12 / 13 / 2016
    • Study of the effect of temporal sampling frequency on DSCOVR observations using the GEOS-5 Nature Run
    • Cloud Properties Of The Daytime Earth As Observed By DSCOVR-EPIC: A First Look

    32nd Conference on Hurricanes and Tropical Meteorology

    4 / 21 / 2016
    • Investigating Sensitivity to Saharan Dust During Hurricane Helene (2006) Using an Adjoint

    AMS Annual Meeting 2016

    1 / 14 / 2016
    • Investigating Sensitivity to Saharan Dust in Atlantic Hurricane Formation Using the GEOS-5 Adjoint Model
    • Assessment of the Current Satellite Observing System Using the GEOS-5 Observation Impact Monitoring Tool

    AMS Annual Meeting 2017

    1 / 23 / 2016
    • Forecast Sensitivity Observation Impact (FSOI) Inter-comparison Experiment
    • Development and applications of the adjoint of the non-hydrostatic GEOS-5 FV3 dynamical core
    • Investigating the Source of Track and Intensity Errors in Forecasts of Hurricane Joaquin Using the NASA GEOS-5 and Navy Coamps Adjoint Systems

    AGU Fall Meeting 2015

    12 / 16 / 2015
    • Investigating troposphere-stratosphere coupling during the southern hemisphere sudden stratospheric warming using an adjoint model.

     Goddard Young Scientist Forum

    7 / 15 / 2015
    • Investigating sensitivity to Saharan dust in tropical cyclone formation using the adjoint of GEOS-5

     Eurpoean Geosciences Union Annual Meeting

    4 / 13 / 2015
    • Investigating sensitivity to Saharan dust in tropical cyclone formation using NASA’s adjoint model.
    • Comparison of the tangent linear properties of tracer transport schemes applied to geophysical problems.

     Workshop on Meteorological Sensitivity Analysis and Data Assimilation

    1 / 6 / 2015
    •  Investigating sensitivity to dust in tropical cyclone formation using the GEOS-5 adjoint model

    Brief Bio

    Daniel Holdaway joined NASA's Global Modeling and Assimilation Office in February 2011. Since then he has worked in the atmospheric data assimilation group and specializes in the development of the tangent linear and adjoint versions of GEOS-5. He has developed linearizations of the non-hydrostatic FV3 cubed sphere dynamical core and the convection, cloud, radiation, aerosol and boundary layer schemes. The adjoint of GEOS-5 is one of the most capable in the World and is used for a number of research and operational applications by GMAO and external collaborators.

    Daniel is interested in using the adjoint of GEOS-5 for a number of research applications, especially investigating how initial condition errors can impact forecasts of tropical cyclones and hurricanes. Using the adjoint he has looked at how Saharan dust can impact developing storms and how small scale errors can impact track. He has also used the adjoint to investigate the causes of sudden stratospheric warming. 
     

    Publications

    Refereed

    Holdaway, D., and Y. Yang. 2016. "Study of the Effect of Temporal Sampling Frequency on DSCOVR Observations Using the GEOS-5 Nature Run Results (Part I): Earth’s Radiation Budget." Remote Sens. 8 (2): 98 [10.3390/rs8020098]

    Holdaway, D., and Y. Yang. 2016. "Study of the Effect of Temporal Sampling Frequency on DSCOVR Observations Using the GEOS-5 Nature Run Results (Part II): Cloud Coverage." Remote Sensing 8 (5): [10.3390/rs8050431]

    Holdaway, D. R., and J. Kent. 2015. "Assessing the tangent linear behaviour of common tracer transport schemes and their use in a linearised atmospheric general circulation model ." Tellus A 67 27895 [10.3402/tellusa.v67.27895]

    Holdaway, D., R. M. Errico, R. Gelaro, J. G. Kim, and R. B. Mahajan. 2015. "A Linearized Prognostic Cloud Scheme in NASA’s Goddard Earth Observing System Data Assimilation Tools." Monthly Weather Review 143 (10): 4198-4219 [10.1175/MWR-D-15-0037.1]

    Holdaway, D. R., and R. M. Errico. 2014. "Using Jacobian sensitivities to assess a linearization of the relaxed Arakawa-Schubert convection scheme." Q.J.R. Meteorol. Soc. 140 (681): 1319-1332 [10.1002/qj.2210]

    Holdaway, D. R., R. M. Errico, R. Gelaro, and J. G. Kim. 2014. "Inclusion of Linearized Moist Physics in NASA’s Goddard Earth Observing System Data Assimilation Tools." Mon. Weather Rev. 142 (1): 414-433 [10.1175/MWR-D-13-00193.1]

    Holdaway, D. R., J. Thuburn, and N. Wood. 2013. "Comparison of Lorenz and Charney–Phillips vertical discretisations for dynamics–boundary layer coupling. Part II: Transients." Quarterly Journal of the Royal Meteorological Society 139 (673): 1087–1098 [10.1002/qj.2017]

    Holdaway, D. R., J. Thuburn, and N. Wood. 2013. "Comparison of Lorenz and Charney–Phillips vertical discretisations for dynamics–boundary layer coupling. Part I: Steady states." Quarterly Journal of the Royal Meteorological Society 139 (673): 1073-1086 [10.1002/qj.2016]

    Holdaway, D. R., J. Thuburn, and N. Wood. 2007. "On the relation between order of accuracy, convergence rate and spectral slope for linear numerical methods applied to multiscale problems." International Journal for Numerical Methods in Fluids 56 (8): 1297-1303 [10.1002/fld.1644]

                                                                                                                                                                                            
    NASA Logo, National Aeronautics and Space Administration