Birkelandsforelesningen 2009

Extreme space weather

Åpent
Videnskapsakademiets hus, Drammensveien 78
Prof. Dr. Paul M. Kintner, Jr

Paul Kintner has been a professor of Electrical and Computer Engineering at Cornell University since 1991. He received his Ph.D. in physics from the University of Minnesota in 1974, then was a postdoctoral research associate at the University of Iowa in Prof. Van Allen's group from 1974-1976. He came to Cornell University in 1976 as a research associate and was promoted to assistant professor in 1981 and associate professor in 1985. He was associate director from1997-2001. As of September 1, 2010, he is a Jefferson Fellow with the U.S. Department of State. 

 

Prof. Kintner's scientific interests include the Geospace environment and the development of instrumentation for both in situ sensing on rockets and satellites and ground-based re­mote sensing. During the past 10 years, he has initiated a program to develop Global Positioning System receivers for scientific ap­plications, including ground-based GPS receivers to monitor ionospheric scintillations and ionospheric drifts and space flight GPS receivers for time synchronization and precision positioning on multiple payload sounding rockets.  He has been the principal investigator for eight sounding rockets, three of which were launched from Norway, and a co-investigator or contributor to 30 more space flight experiments. He is the author or co-author of more than 180 scientific publications on space physics and space weather.

 

Dr. Kintner was chair of the NASA Living With a Star/Geospace Mission Definition Team from 2001-2002. He is a fellow of the American Physical Society, a member of the American Geophysical Union, a senior member of the Institute of Electrical and Electronic Engineers, a senior member of the American Institute of Aeronautics and Astronautics, and a member of the Institute of Navigation. Dr. Kintner developed and teaches courses such as "GPS: Theory and Design" and "Advanced GPS Receiver Design", resulting in several teaching awards. Recently, he served on the National Research Council Committee on the Societal and Economic Impacts of Severe Space Weather Events, leading to this presentation.

Extreme space weather is this year's topic for the Birkeland Lecture. We are already familiar with powerful weather phenomena such as snow- and thunderstorms. Other types of storms can occur in space. These types of storms are known as «sunstorms», and like the earthstorms they can cause problems for us humans. In his lecture, Prof. Dr. Paul M. Kintner, Jr, will explain how these sunstorms emerge and what effect they have. 

”Extreme space weather” har årets Birkelandforeleser, Prof. Dr. Paul M. Kintner, satt som tittel på sitt foredrag. 

Bilde
Reconstruction of the ionospheric storm over North America and the polar regions on October 30, 2003 during a major soar outbursts.
Reconstruction of the ionospheric storm over North America and the polar regions on October 30, 2003 during a major soar outbursts

”Extreme space weather”

 
The sun has its own seasons, and the stormy season will be upon us soon. Every eleven years, the sun enters a period of increased activity called the solar maximum. The FUV (far ultraviolet) portion of the solar spectrum intensifies, making our ionosphere denser and thicker. Frequent solar flares eject up to 10 billion tons of plasma at speeds approaching 1500 kilometers per second, generating intense, broadband bursts of radio waves, magnetic storms at the earth, and stirring up the ionosphere in ways recently thought unimaginable. Called the sunspot cycle, this period of activity is the result of a solar dynamo in which electric currents and magnetic fields are built up in the outer layer of the sun and then destroyed in energetic outbursts. The next sunspot maximum is currently predicted to arrive in May 2013 and to be a relatively weak maximum in terms of sunspot count. One would hope that this is cause for relief, except that the most intense solar outbursts have occurred during below average solar cycles.
 
Birkelandforeleseren 2009
Prof. Dr. Paul M. Kintner
We have survived previous sunspot maxima with few ill effects; why should we not do so again?  The answer is that our technological infrastructure is changing. Longer, higher voltage power grids are more vulnerable to magnetic fields produced by electric currents in space. GPS and other satellite-based services are vulnerable to having their signals interrupted or the satellites damaged. Furthermore, not only have ill effects with serious consequences happened during previous solar maxima, but we also have only a foggy understanding of the severity of space weather. Given a world that is more interconnected with technical systems that are more brittle and less forgiving of unexpected stress, we need to understand the extremes of space weather