Erdal Yiğit, PhD

Associate Professor of Physics
Department of Physics and Astronomy, Space Weather Lab, George Mason University



Introduction

Dr. Yiğit's research focuses on
  • Whole atmosphere coupling
  • Gravity waves in planetary atmospheres
  • General circulation modeling
  • Dynamics of planetary atmospheres
  • Space weather

Biosketch

Erdal Yiğit received his Ph.D. at the University College London, UK, in 2009 in physics. In March 2009, he moved to the USA to work at the University of Michigan's Atmospheric Oceanic and Space Sciences Laboratory as a Postdoctoral Researcher. In 2012, he moved to California for another Postdoctoral position at UC Berkeley's Space Sciences Laboratory, where he has later been promoted to an Assistant Research Physicist position that he kept till August 2013. In September 2013, he joined George Mason University's Physics and Astronomy Department as a tenure-track faculty member. He has been granted tenure in 2018. His research interests cover topics from atmospheric, space and planetary sciences, in particular, global modeling of and internal wave effects in planetary atmospheres, such as, Earth and Mars. He is the developer of the first whole atmosphere gravity wave parameterization suitable for general circulation models of planetary atmospheres. He is the recipient of the 2016 Zeldovich Medal jointly presented by COSPAR and the Russian Academy of Sciences for his significant contributions to the study of coupling between the lower and upper atmospheres on Earth and Mars by gravity waves. He is the sole author of the Springer's two-volume monograph series on "Atmospheric and Space Sciences" one on Neutral atmospheres and the second on Ionospheres and Plasma Environments. He lives in Fairfax, Virginia (VA), USA.

Web Information

Facebook Page : https://www.facebook.com/erdalyigit80/

Twitter: https://twitter.com/ProfErdalYigit

ResearchGate: https://www.researchgate.net/profile/Erdal_Yigit2

Erdal@Mason: www.physics.gmu.edu/people/erdal-yigit/

ORCID iD iconorcid.org/0000-0002-2819-2521

Education

Publications

Summary of Peer-reviewed Publications (Quick Overview)




Publications -- Peer reviewed (2012-2018)


2018

2017


2016


2015


2014


2013


2012




Peer-reviewed Journal Papers (All):

  1. Kuroda, T., A. S. Medvedev, E. Yiğit, P. Hartogh (2016),
    Global distribution of gravity wave sources and fields in the Martian atmosphere during equinox and solstice inferred from a high-resolution general circulation model,
    J. Atmos. Sci, in press.
  2. Yiğit, E., A. S. Medvedev (2016), Role of gravity waves in vertical coupling during sudden stratospheric warmings, Geosci. Lett, 3:27, doi: 10.1186/s40562-016-0056-1.
  3. Kilcik, A., A. Ozguc, E. Yiğit, V. Yurchyshyn, Burcin Donmez (2016), Signature of a possible relationship between the maximum CME speed index and the critical Frequencies of the f1 and f2 Ionospheric Layers: Data Analysis for a Mid-Latitude Ionospheric Station during the Solar Cycles 23 and 24, J. Atmos. Sol.-Terr. Phys., in press.
  4. Medvedev, A. S., H. Nakagawa, C. Mockel, E. Yiğit, T. Kuroda, P. Hartogh, K. Terada, N. Terada, K. Seki, N. M. Schneider, S. K. Jain, J. S. Evans, J. I. Deighan, W. E. McClintock, D. Lo (2016), Comparison of the Martian thermospheric density and temperature from IUVS/MAVEN data and general circulation modeling, Geophys. Res. Lett., in press.
  5. England, S., G. Liu, P. Withers, E. Yiğit, D. Lo , S. Jain, N. Schneider, J. Deighan, W. McClintock, P. Mahaffy, M. Elrod, M. Benna, B. Jakosky (2016), Simultaneous observations of atmospheric tides from combined in situ and remote observations at Mars from the MAVEN spacecraft, J. Geophys. Res. - Planets, in press.
  6. Yiğit, E., P. K. Knizova, K. Georgieva, W. Ward (2016), A review of vertical coupling in the Atmosphere-Ionosphere system: Effects of waves, sudden stratospheric warmings, space weather, and of solar activity, J. Atmos. Sol.-Terr. Phys., 141, 1-12, 10.1016/j.jastp.2016.02.011.
  7. Yiğit, E., H. U. Frey, M. B. Moldwin, T. J. Immel, A. J. Ridley (2016), Hemispheric difference in the response of the upper atmosphere to the August 2011 geomagnetic storm: A simulation study, J. Atmos. Sol.-Terr. Phys., 141, 13-26, doi: 10.1016/j.jastp.2015.10.002.
    • A general circulation model is used to simulate the effects of a major geomagnetic storm on the thermosphere-ionosphere on Earth
    • Advective forcing plays a role in influencing hemispheric asymmetry during the different phases of the storm
  8. Kuroda, T., A. S. Medvedev, E. Yiğit, P. Hartogh (2015), A global view of gravity waves in the Martian atmosphere inferred from a high-resolution general circulation model, Geophys. Res. Lett., doi:10.1002/2015GL066332.
    • First results of gravity wave simulations with a new high-resolution Martian general circulation model are presented,
    • Modeled small-scale gravity wave temperature variances are in a good agreement with Mars Global Surveyor radio occultation data.
  9. Yiğit, E., S. L. England, G. Liu, A. S. Medvedev, P. R. Mahaffy, T. Kuroda, and B. M. Jakosky (2015), High-altitude gravity waves in the Martian thermosphere observed by MAVEN/NGIMS and modeled by a gravity wave scheme, Geophys. Res. Lett., 42, doi:0.1002/2015GL065307.
  10. Yiğit, E., A. S. Medvedev, and P. Hartogh (2015), Gravity waves and high-altitude CO2 ice cloud formation in the Martian atmosphere , Geophys. Res. Lett., 42, doi:10.1002/2015GL064275.
    • Gravity waves facilitate CO2 ice cloud formation in the upper mesosphere of Mars
  11. Medvedev, A. S., F. Gonzales-Galindo, E. Yiğit, A. G. Feofilov, F. Forget, and P. Hartogh (2015), Cooling of the Martian thermosphere by CO2 radiation and gravity waves: An intercomparison study with two general circulation models, J. Geophysical Res. - Planets, 120, doi:10.1002/2015JE004802.
  12. Yiğit, E. , and A. S. Medvedev (2015), Internal wave coupling processes in Earth's atmosphere, Adv. Space Res., 55, doi: 10.1016/j.asr.2014.11.020.
    • A contemporary review of internal wave processes in Earth's atmosphere, discussing atmospheric variability and sudden stratospheric warming
    • Gravity waves, solar tides, Kelvin waves, and planetary (Rossby) waves are introduced.
  13. Yiğit, E. , A. S. Medvedev, S. L. England, and T. J. Immel (2014), Simulated variability of the high-latitude thermosphere induced by small-scale gravity waves during a sudden stratospheric warming , J. Geophys. Res.-Space Phys., 119, doi: 10.1002/2013JA019283.
    • GW mean dynamical effects in the high-latitude thermosphere increase by up to a factor of 3 to 6 during the warming. The temporal variability of GW drag increases by more than one order of magnitude, exceeding locally the mean GW drag by more than a factor of two at the peak of the warming.
    • The simulated zonal winds exhibit up to 60% increase of smaller-scale temporal variability
    • Enhanced propagation of subgrid-scale GWs into the high-latitude thermosphere directly affects the temporal variability of resolved motions that have smaller spatial and temporal scales than that of solar tides.
  14. Medvedev, A. S., E. Yiğit, T. Kurada, P. Hartogh (2013), General circulation modeling of the Martian upper atmosphere during global dust storms, J. Geophys. Res.-Planets, 118, 1–13, doi:10.1002/jgre.20163.
    • Simulation of two major dust storms on Mars.
    • Atmospheric density during dust storms enhanced in average by a factor of 2 to 3 in the mesosphere and lower thermosphere.
    • Significant impact of the dust storm on the gravity wave propagation and dissipation
  15. Yiğit, E., and A. S. Medvedev (2012), Gravity waves in the thermosphere during a sudden stratospheric warming, Geophys. Res. Lett., 39, L21101, doi:10.1029/2012GL053812.
    • More fast westerly GW harmonics to penetrate into the lower and upper thermosphere during sudden stratospheric warmings.
    • Towards the end of the warming, the imposed westerly GW drag slows down and even reverses the easterlies in the high-latitude mesosphere and lower thermosphere (MLT).
  16. Yiğit, E., A. J. Ridley, and M. B. Moldwin (2012), Importance of capturing heliospheric variability for studies of thermospheric vertical winds, J. Geophys. Res.-Space Phys., 117, A07306, doi: 10.1029/2012JA017596.
  17. Vichare, G., A. J. Ridley, and E. Yiğit (2012), Quiet time ionospheric potential distribution in the non-hydrostatic global ionosphere-thermosphere model, J. Atmos. Sol-Terr. Phys., 80, 161-172.
  18. Medvedev, A. S., and E. Yiğit (2012), Thermal effects of internal gravity waves in the Martian upper atmosphere, Geophys. Res. Lett., 39, L05201, doi:10.1029/2012GL050852.
  19. Yiğit, E., A. S. Medvedev, A. J. Ridley, A. D. Aylward, M. J. Harris, M. Moldwin, and P. Hartogh (2012), Dynamical effects of internal gravity waves in the equinoctial thermosphere, J. Atmos. Sol.-Terr. Phys., 90-91, 104-116.
  20. Yiğit, E. , A. J. Ridley (2011), Role of variability in determining vertical wind speed and variability, J. Geophys. Res.-Space Phys., 116, A12305, doi:10.1029/2011JA016714.
    • Thermospheric ion flows control the vertical wind variability and speed.
    • Variable ion flows generate enhanced Joule heating that cause nonhydrostatic acceleration of the vertical winds.
  21. Medvedev, A. S., E. Yiğit, P. Hartogh, E. Becker (2011), Influence of gravity waves on the Martian atmosphere: General circulation modeling, J. Geophys. Res.-Planets, 116, doi:10.1029/2011JE003848.
  22. Medvedev, A. S., E. Yiğit, P. Hartogh (2011), Estimates of gravity wave drag on Mars: Indication of a possible lower thermospheric wind reversal, Icarus, 211, 909-912, doi:10.1016/j.icarus.2010.10.013.
    • Implementation of the Yiğit et al. (2008) gravity wave parameterization into a Martian General Circulation Model.
    • Strong dynamical influence of gravity waves on the Martian circulation between 100 and 130 km.
  23. Yiğit, E., and A. J. Ridley (2011), Effects of high-latitude thermosphere heating at various scale sizes simulated by a nonhydrostatic global thermosphere ionosphere model, J. Atmos. Sol-Terr. Phys., 73, 592-600, doi:10.1016/j.jastp.2010.12.003.
    • Thermospheric Joule heating is simulated at very high resolution with the Global Ionosphere Thermosphere Model
  24. Yiğit, E., and A. S. Medvedev (2010), Internal gravity waves in the thermosphere during low and high solar activity: Simulation study, J. Geophys. Res.-Space Physics, 115, A00G02, doi:10.1029/2009JA015106.
  25. Cnossen, I., M. J. Harris, N. F. Arnold, and E. Yiğit (2009), Modelled effect of changes in the CO2 concentration on the middle and upper atmosphere: Sensitivity to gravity wave parameterization and absolute concentrations, J. Atmos. Sol-Terr. Phys., 71, 1484–1496.
  26. Yiğit, E., and A. S. Medvedev (2009), Heating and cooling of the thermosphere by internal gravity waves, Geophys. Res. Lett., 36, L14807, doi:10.1029/2009GL038507.
  27. Yiğit, E., A. S. Medvedev, A. D. Aylward, P. Hartogh, and M. J. Harris (2009), Modeling the effects of gravity wave momentum deposition on the general circulation above the turbopause, J. Geophys. Res.-Atmospheres, 114, D07101, 14, doi:10.1029/2008JD011132.
    • Implementation and validation of the Yiğit et al. (2008) scheme in a coupled middle atmosphere thermosphere model.
    • Gravity waves penetrate into the thermosphere above the turbopause producing dynamical effects that are comparable to ion drag.
  28. Yiğit, E., A. D. Aylward, and A. S. Medvedev (2008), Parameterization of the effects of vertically propagating gravity waves for thermosphere general circulation models: Sensitivity study, J. Geophys. Res.-Atmospheres, 113, D19106, doi:10.1029/2008JD010135.
    • First gravity wave parameterization that is suitable for whole atmosphere general circulation models extending from the lower atmosphere to the upper thermosphere
    • Linear gravity wave parameterization overestimates gravity wave effects, while the nonlinear saturation produces better gravity wave effects.

PhD Thesis

  1. Yiğit, E. (2009), Modelling atmospheric vertical coupling: role of gravity wave dissipation in the upper atmosphere, UCL PhD Thesis.

Books

  1. Yiğit, E. (2015), Atmospheric and Space Sciences: Neutral Atmospheres, Volume 1 , Springer Briefs in Earth Sciences. Bookmetrix
  2. Yiğit, E. (2018), Atmospheric and Space Sciences: Ionospheres and Plasma Environments, Volume 2 , Springer Briefs in Earth Sciences. Bookmetrix

Book chapter (Peer-reviewed)

  1. Yiğit, E., and A. S. Medvedev (2013), Extending the parameterization of gravity waves into the thermosphere and modeling their effects, in Climate and Weather of the Sun-Earth System (CAWSES), edited by F.-J. Lbken, Springer Atmospheric Sciences, pp. 467-480, Springer Netherlands, doi:10.1007/978-94-007-4348-9 25.

Other Articles

  1. Yiğit, E., T. Nakamura, C. Stolle, ROSMIC's Coupling by Dynamics-Working Group, VarSITI Newsletter, 10, p 1.
  2. Yiğit, E. (2011), Thermospheric effects of lower atmospheric small-scale gravity waves, CAWSES-II TG4 Newsletter: Highlight on Young Scientists, 4, p. 6.

Publication Lists

 

Profiles

 

PhD Thesis supervised