Brian Tinsley

Brian Tinsley

Professor Emeritus - Physics
Tags: Physics

Professional Preparation

Ph.D. - Physics
University of Canterbury - 1963
M.Sc. - Physics
University of Canterbury - 1961
B.Sc. - Physics
University of Canterbury - 1958

Research Areas

Overview
 Observational and theoretical work on effects of global atmospheric electricity on weather and climate, both from external (solar  wind) and internal (e.g., thunderstorm) sources. Models of effects of current flow in the Global Electric Circuit on charging of aerosols and cloud droplets, and effects of such charges on cloud microphysics, weather and climate.

Research Interests
 Dr. Tinsley has been actively involved in observational and theoretical research on upper atmosphere processes (Aeronomy) for more than 60 years, and has served on many national and international organizations in this field. In 1986-88, while serving as Program Director for Aeronomy at the National Science Foundation, he had the opportunity to discuss long-standing problems in atmospheric science with program directors in areas of meteorology. This led him to begin research on the centuries old question of the effects of changes in the sun on day-to-day weather, and year-to year and century time scale climate change. During the past 34 years he has been author or co-author of more than 45 papers on such effects, including both data analysis and modeling. He has developed a theory that involves the solar wind, as an alternative to the traditional view that changes in solar brightness were responsible. The solar wind is a highly conducting, extremely hot gas that blows from the sun outward over the earth. It impedes the flow of high energy cosmic ray particles coming in from the galaxy, and energizes high energy electrons in the earth's radiation belts that precipitate into the atmosphere; both of these effects change the column conductivity between the ionosphere and the earth's surface. The solar wind also changes the potential difference between the ionosphere and the earth in the polar cap regions, and guides solar flare particles into the polar caps. All four effects alter the ionosphere-earth current density (Jz) that is part of the global atmospheric electric circuit, and which flows down from the ionosphere to the surface and through clouds.

 In the gradients of conductivity at boundaries of clouds and aerosol layers and near the surface (especially near ocean surfaces) the current flow generates a changing potential gradient and a layer of space charge (unipolar charge) in accordance with Poisson's equation. This charge is transferred from air ions to aerosol particles and to droplets, and is convected upwards into storm clouds. The predominance if charge of one sign reduces the scavenging rates (electro-anti-scavenging) and for a distribution with small droplets this can predominate over image-charge scavenging (electro-scavenging) that would otherwise increase the scavenging rates.

 There are good correlations, on the day-to-day time scale, between the four solar wind - modulated inputs to Jz mentioned above and with the small changes in the opacity of stratiform clouds and in atmospheric temperature and dynamics, both in the Arctic and the Antarctic. Similar changes are found with Jz changes due to the thunderstorm generators of the global electric circuit. 

 For clouds with their tops above the freezing level, another process  is the electrical enhancement of the rate of scavenging of ice-forming nuclei (IFN), that increases the rate of contact ice nucleation. This has consequences for cloud thickness and reflectivity to sunlight, and for precipitation rates and latent heat transfer, both of which are capable of affecting atmospheric temperature and dynamics. This mechanism also explains many reports of high rates of ice formation in certain types of clouds that has been a long-standing puzzle for cloud physicists.

  The charge modulation of aerosol scavenging described above increases the scavenging rate and decreases the concentration of the large CCN (electro-scavenging) but decreases the rate of scavenging (electro-anti-scavenging) and increases the concentration of small CCN otherwise due to diffusion scavenging.  This changes the droplet size distribution in subsequent cloud formation, and reduces the droplet coagulation and production of rain. As well as increasing cloud opacity in stratiform clouds, this allows more liquid water to be carried above the freezing level in deep convective storms, (the Rosenfeld mechanism) and the extra release of latent heat of freezing invigorates the updrafts of the storm. In winter cyclones this increases storm vorticity, and explains many reports of winter storm vorticity correlated with Jz. By extension this applies to effects on winter severity in the UK and Western Europe at solar minima, when Jz is tens of percent higher than at solar maxima. The link is sustained storm invigoration over solar minima winters enhancing blocking situations that reduce the flow of warm, moist air off the ocean. 

There are well documented correlations of climate during past millennia with cosmic ray flux changes. These can be understood in terms of electrical interactions between cloud droplets and aerosol particles responding to solar wind-induced changes in atmospheric ionization and in Jz, as discussed above.

 In a collaboration with Dr. Gary Burns of the Australian Antarctic Division we have confirmed with high statistical significance small changes in Antarctic surface pressure with small solar wind-induced changes in Jz, which are consistent with our hypothesized effects on Jz on clouds and storms. In the Arctic the Jz changes are of opposite sign, as are the correlated pressure changes. Further, there are pressure changes that correlate with Jz changes due to changes in the current output of low-latitude thunderstorm generators, that have the same sign in the Arctic as in the Antarctic, as expected from theory. The implication is that changes in Jz produce changes in many clouds, and in cases of deep convection and winter storms at high latitudes, changes in storm invigoration, vorticity, and winter circulation. Recent work by Lam et al. from the British Antarctic Survey, and Frederick from the University of Chicago on polar atmospheric temperature and cloud cover support the above hypothesis of electrical effects on cloud microphysics 

Publications

Uncertainties in evaluating global electric circuit interactions with atmospheric clouds and aerosols, and consequences for radiation and dynamics, B. A. Tinsley. J. Geophys. Res. Atmos., 127, e2021JD03954.  doi.org/10.1029/2021JD035954 2022 - Publication
Seasonal and solar wind duration influences on correlation of high latitude clouds with ionospheric potential, B. A. Tinsley, Limin Zhou, Lin Wang, and Liang Zhang. J. Geophys. Res.–Atmos., 126, 2020JD034201.  doi.org/10.1029/2020JD034201 2021 - Publication
Low latitude lightning activity responses to cosmic ray Forbush decreases, Liang Zhang, B. A. Tinsley and Limin Zhou.  Geophys. Res. Lett., 47, e2020GL087024. doi.org/10.11029/2020GL087024 2020 - Publication
Parameterization of aerosol scavenging due to atmospheric ionization Part 4: Effects of varying altitude. Liang Zhang, B. A. Tinsley and Limin Zhou. J. Geophys. Res. Atmos., 124, 13,105-13,126. doi.org.10.1029/2018JD030126 2019 - Publication
Parameterization of aerosol scavenging due to atmospheric ionization Part 3: Effects of varying droplet radius. Liang Zhang, B. A. Tinsley, and Limin Zhou.  J. Geophys. Res. Atmos., 123, 10,546-10,567.  doi.org/10.1029/2018JD028840 2018 - Publication
The response of longwave radiation at the South Pole to electrical and magnetic variations: Links to meteorological generators and the solar wind. J. E. Frederick, and B. A. Tinsley. J. Atmos. Solar-Terr. Phys., 179, 214-224,2018.  doi.org/10.1016/j.jastp.2018.08.003 2018 - Publication
Parameterization of In-Cloud Aerosol Scavenging due to Atmospheric Ionization Part 2: Effects of Varying Particle Density, Liang Zhang and B. A. Tinsley, J. Geophys. Res. Atmos., 123, 3009-3115. doi.org/10.1002/2017JD027884. 2018 - Publication
The Zonal-Mean and Regional Tropospheric Pressure Responses to Changes in Ionospheric Potential, L. Zhou, B. Tinsley, L. Wang, and G. Burns, J. Atmos. Solar Terr. Phys.,171, 111-118, 2018.   doi.org/10.1016/j.jastp.2017.07.010  2018 2018 - Publication

Appointments

Professor Emeritus
The University of Texas at Dallas [2011–Present]
Professor
The University of Texas at Dallas, formerly Southwest Center for Advanced Studies [1976–2011]
Associate Professor
The University of Texas at Dallas, formerly Southwest Center for Advanced Studies [1970–1976]
Assistant Professor
The Southwest Center for Advanced Studies, which became the University of Texas at Dallas [1967–1970]
Research Associate
Southwest Center for Advanced Studies [1966–1967]
Research Scientist
Southwest Center for Advanced Studies [1963–1966]

Presentations

Observing the Frontier: The Search for Mechanism of Solar Influences on Weather and Climate
2019/02 A video of this presentation is available. This presentation discusses the work of my colleagues and I for the past 30 years, and the larger scientific community for the past two centuries, have been doing on the search for mechanisms connecting activity on the sun, for example as seen in sunspots and in space weather, with natural changes in ambient weather and climate.

Activities

SPECIAL ACTIVITIES
  • Chairman, Division II, Aeronomic Phenomena, of IAGA, 1973-1979
  • Member, U.S. Committee on Extension of the Standard Atmosphere, 1974-1976
  • Associate Editor, Journal of Geophysical Research, 1974-1978
  • Member, Committee on Solar Terrestrial Research of the NAS, 1975-1979
  • Member, U.S. National Committee for IUGG, 1979-1982
  • Discipline Scientist, SCOSTEP, 1976-1982
  • Reporter, Exospheres Division II, IAGA, 1979-1983
  • Member, SCOSTEP Committee for Future Aeronomy Programs, 1981-1983
  • Member, Steering Committee for CEDAR (Coupling Energetics and Dynamics of
  • Atmospheric Regions), 1984-1988
  • Convener, 1987 AGU Symposium on Solar Variability, Weather and Climate
  • Convener, 1989 AAAS Symp. "Weather and Climate; Solar Variability and QBO Connections"
  • Convener, with S. Avery, June 1989 CEDAR/NCAR Workshop "Mechanisms for
  • Tropospheric Effects of Solar Variability and the QBO"
  • Convener, 1989 AGU Symp. "Mechanisms for Atmospheric Effects of Solar Variability and the QBO."
  • Associate Editor, Reviews of Geophysics, 1988-1992
  • Convener, with G. Keating, 1991 AGU Symposium "Atmospheric Response to Solar Photons and Energetic Particle Radiation"
  • Convener, with K. Beard, 1996 Workshop at Los Alamos National Lab., "Links between Variations in Solar Activity, Atmospheric Conductivity, and Clouds"
  • Convener, with O. Troshichev, 1997 IAGA Symposium, "Solar-and Solar Wind Effects on Weather and Climate".
  • Member 1998-2002 AGU Committee on Atmospheric and Space Electricity (CASE)
  • Steering Committee Member, 1999-2003, European Science Foundation Network,
  • "Space Processes and Electrical Charges Influencing Atmospheric Layers' -(SPECIAL).
  • Convener, with O. Troshichev, 2004 AGU Session "Forcing of the Antarctic Stratosphere and Southern Tropospheric Circulation by Solar Activity"
  • Convener, with S. Lloyd, F. Yu and H. Svensmark, 2005 AGU Session "Cosmic Rays, Clouds, and Climate"
  • Convener, with J. Pap, 2010 COSPAR sessions on "Solar Variability, Cosmic Rays, and Climate" at Bremen, Germany, July18-25, 2010.