The Center for Atmospheric Sciences | » Ernest M. Nyaku

    • Ph. D, Atmospheric Science, Hampton University, 2016

    • MS, Applied Mathematics, Hampton, 2010

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      Recent News:

      June 1, 2015 : APS Exhibit lights up CNU STEM Day
      Fire tornado demonstration.

      The Hampton University Atmospheric and Planetary Science Department took its show on the road on Saturday, May 30, to Christopher Newport University’s annual STEM Day celebration.  Faculty members John McNabb and William Moore were joined by graduate students John Blalock, Liqiao Lei, and Earnest Nyaku inside and outside the CNU Field House to demonstrate atmospheric […]

  • Ernest M. Nyaku

    I have recently been awarded a Ph.D in atmospheric science from the department of atmospheric and planetary science in Hampton University. I earned my my bachelor’s degree at the Kwame Nkrumah University of Science and Technology in Kumasi, Ghana in 2001 majoring in Mathematics and Statistics. In 2010, I was awarded a Masters degree in Applied Mathematics at Hampton University and then proceeded into a Ph.D program in the Department of Atmospheric and Planetary Science, where was honored to work with Dr. Robert Loughman as my advisor on my Ph.D dissertation.

    During my first two years in the Ph.D program, I assisted with several sensitivities studies to prepare the retrieval algorithms for the Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (LP) instrument, which was launched in October 2011,as acknowledged in [1] .
    These studies included investigating:
    – how each of the three spectral bandpass characteristics used in the retrieval algorithm affected the total ozone retrievals.
    – the effect of reducing the number of wavelengths used in the multiple scattering grid (Q-grid) for ozone retrievals for the full orbit.
    – the effect of cloud height retrievals on the ozone retrievals.

    In my third year, I participated in the radiative transfer model modifications documented in [12], for which I am a co-auther.
    My Ph.d dissertation title was “Characterizing Aerosol Properties in the Upper Troposphere and Stratosphere from Limb Scatter Radiance”.
    The research involved, finding how well the stratospheric aerosol phase function could be characterized from limb scatter geometry and applied to the retrieval of the stratospheric aerosol extinction profile by using the OMPS forward model and also how this extinction retrieved compared to that of other limb scattering instruments (OSIRIS and SCIAMACHY) that employ different phase functions in their retrieval algorithms.

    [1] D. F. Rault, R. P. Loughman, "The OMPS limb profiler environmental data record algorithm theoretical basis document and expected performance", IEEE Transactions on Geoscience and Remote Sensing, 2013, 51, 5, 2505-2527 view bibtex
    [2] R.P. Loughman, D. E. Flittner, E. M. Nyaku, 'et., "Gauss-{S}eidel limb scattering ({GSLS}) radiative transfer model development in support of the Ozone Mapping and Profiler Suite ({OMPS}) limb profiler mission", Atmospheric Chemistry and Physics, 2015, 15, 6, 3007-3020 view bibtex

    Project: Characterizing aerosol properties in the upper troposphere and stratosphere from limb scatter radiance

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    The most important stratospheric aerosol property for most applications is the aerosol extinction coefficient ka, which represents the rate at which energy is removed by aerosols from a beam per unit of path length traversed, and varies with both altitude z and wavelength λ. The aerosol single-scattering albedo (SSA) indicates the fraction of aerosol extinction […]

    Project: Limb Scattering Radiative Transfer Model Development in Support of the Ozone Mapping and Profiler Suite (OMPS) Limb Profiler Mission

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    My recent work has been funded by NASA through a sub-contract with SSAI, which has supported radiative transfer model improvements relevant for the Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (LP) sensor.  This sensor launched aboard the Suomi NPP satellite in October 2011, and the current acting leader for the OMPS LP algorithm team […]