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.
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.
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.
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)
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]
GE Whitney Symposium
10 / 12 / 2015JCSDA Summer Colloquium
8 / 4 / 2015AGU Fall Meeting 2016
12 / 13 / 201632nd Conference on Hurricanes and Tropical Meteorology
4 / 21 / 2016AMS Annual Meeting 2016
1 / 14 / 2016AMS Annual Meeting 2017
1 / 23 / 2016AGU Fall Meeting 2015
12 / 16 / 2015Goddard Young Scientist Forum
7 / 15 / 2015Eurpoean Geosciences Union Annual Meeting
4 / 13 / 2015Workshop on Meteorological Sensitivity Analysis and Data Assimilation
1 / 6 / 2015Daniel 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.
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]