Brian Tinsley

Brian Tinsley is a physicist who has been actively researching upper atmosphere processes (Aeronomy) for more than 50 years. He has been a Professor of Physics at the University of Texas at Dallas since 1976 and has served on many national and international organizations in this field. He obtained his PhD from the University of Canterbury in New Zealand in November, 1963, for research on optical emissions from the upper atmosphere (airglow and aurorae). With his wife, Beatrice Tinsley, he came to Dallas to work at the newly formed Southwest Center for Advanced Studies, which became the University of Texas at Dallas in 1969. Beatrice obtained a Ph. D. in astrophysics at the University of Texas at Austin, and became a prominent astrophysicist before she died in 1981, resulting in the University of Texas at Austin creating the endowed professorship that bears her name.

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 to him begin research on the centuries old question of the effects of changes in the sun on weather, year-to year climate changes, and global warming on the decadal and century timescale. During the past 22 years he has been author or co-author of more than 40 papers on aspects of such effects, including both data analysis and modeling. He has proposed a mechanism in which the link to the atmosphere is the solar wind (space weather), 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 electric field also changes the potential difference between the ionosphere and the surface in the polar cap regions, and guides solar flare particles into the polar caps. All four inputs 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 deposits electric charge on clouds. Dr Tinsley and students and colleagues have demonstrated good correlations on the day-to-day timescale between each of the four solar wind inputs affecting Jz and small changes in atmospheric temperature and dynamics^[1].

He formed the hypothesis that the Jz effects are due to electrical charge deposited on droplets and aerosol particles (notably condensation nuclei and ice-forming nuclei in clouds) that significantly affects scavenging processes and the concentrations of the nuclei^[2]. The consequences of this include changes in cloud cover and rates of precipitation, and changes in atmospheric dynamics and the jet streams, as has been observed.

This work has led to a potentially very important result. Dr. Tinsley and Dr. Burns of the Australian Antarctic Research Division and Dr. Tinsley’s graduate student Leo Hebert, have shown that there are clear correlations between the electrical current output of the internal atmospheric generators (thunderstorms) in the global electric circuit and surface pressure at both Antarctic and Arctic sites, fully consistent with the externally forced changes^[3]. Thus the work has led to the discovery of a completely unexpected process in meteorology that has implications for climate change. That is that the internal generation of atmospheric electricity, mostly in the tropical regions, affects clouds and meteorological processes all over the globe, and because this current generation changes on daily, seasonal, and longer timescales (notably with global warming) it is an additional input to weather and climate on those timescales that has not been included in current global climate change models. Also, the solar-induced changes have yet to been included, and both of these would modify the current predictions of global warming due to human activities.

Dr. Tinsley collaborates on projects with scientists in Australia, England, China, and the USA; receives invitations to talk at national and international meetings and universities. He organized a three-day symposium in August 2010 in Bremen, Germany on ‘Solar Variability, Cosmic Rays and Climate’, and gave an invited keynote review at a symposium in Goa, India in January 2011.

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