Date: Wednesday, August 8, 2007
Time: 10:30am
Location: NIA, Room 137
Additional Information: Presentation (.pdf)

Space Weather Prediction: Role of Potential Field
Source Surface Model and Its Limitations
Bala Poduval, Stanford University

It is well known that solar originated disturbances in the space affect technological systems both on Earth and in space but the term "Space Weather" came into existence only recently. Life on earth has become so dependent on various modern technologies both ground based and space borne that it has become essential to know the conditions in space,"space weather", well in advance for the successful performance of these technological systems and thereby life on earth. This calls for the forecast of space weather. The Earth is embedded in the solar wind, and the magnetosphere protects the Earth's atmosphere from the direct influences of solar wind ions. The changes in the solar wind conditions caused by the solar variances can cause disturbances in the magnetosphere which in turn trigger various
changes in the Earth's atmosphere. In and around the magnetosphere are all the research, telecommunication, navigation and weather satellites stationed. Therefore, systematic forecast of solar wind near the Earth's environment is one of the prime concerns of Space Weather.

I present here a method that is widely in use in predicting the solar wind conditions near the Earth, based on photospheric observations of the solar magnetic field and a coronal model known as Potential Field Source Surface (PFSS) model. Emphasize will be on the limitations of this model and the need to modify the existing technique.