HR: 0830h
AN: SA41B-0429    [PDF]
TI: Long-term change in mesopause region temperatures over Fort Collins, CO (41N, 105W): Solar cycle effect and trends
AU: * She, C
EM: joeshe@lamar.colostate,edu
AF: Colorado State University, 200 West Lake Street, Fort Collins, CO 80523-1875 United States
AU: Krueger, D A
EM: krueger@lamar.colostate,edu
AF: Colorado State University, 200 West Lake Street, Fort Collins, CO 80523-1875 United States
AB: The Colorado State University Sodium Lidar has measured temperatures in the mesopause region (80-105km) for over 12 years. Based on 7 years' observation, an episodic change with a warming of 11.8K in 1993 at the mean mesopause altitude of 98km, attributable to Mt. Pinatubo eruptions, was reported. In this paper, we focus on the solar cycle effects. With 11 years of data to the end of 2001, we observed a maximum solar response of 0.06K/SFU at 99km, which decreases at lower and higher altitudes to nearly zero and appears to change sign at ~82km and ~104km. The phase changes are consistent with earlier midlatitude observation with incoherent scatter radar above and Rayleigh lidar below the altitudes reported here, providing clear experimental evidence of dynamical influences thoughout different layers of Earth's atmosphere. We discussed the altitude dependence of response amplitudes and delay the volcanic and solar flux effects have on the mesopause region temperatures, as well as long-term temperature trends. In this paper, we re-investigate the questions with the 2002 data added, and take up the question of seasonal dependence (summer vs winter) as well as difference in QBO phases (east vs. west).
DE: 1620 Climate dynamics (3309)
DE: 1650 Solar variability
SC: SPA - Aeronomy [SA]
MN: 2003 Fall Meeting