Statistics on Global Alfvén Wave Deposition over the Polar Region

The importance of Alfvén waves to energy transport inside the magnetosphere has been demonstrated. During substorms some of the largest, most energetic Alfvén waves are observed in the magnetotail. Most of their energy carried to lower altitude is dissipated inside the auroral acceleration region via particle acceleration, as confirmed from low-altitude observations. In this presentation we compare the global contributions of Alfvén wave power to the polar-auroral region during different phases of substorms, including functional relationships to the AE and Kp indices. These results will be compared to ionospheric Joule heating rates at high latitudes. Data were collected from an ideal vantage point, namely, above the nominal auroral acceleration region, over a six-year period of Polar spacecraft operation.