HR: 0800h
AN: GC31B-0350    [Abstracts]
TI: How important are PMOD and ACRIM TSI satellite composites for the global warming debate?
AU: * Scafetta, N
EM: ns2002@duke.edu
AF: Duke University, Physics Department, Durham, NC 27707, United States
AB: We discuss the climate consequences of PMOD and ACRIM TSI satellite composite (1978-2006). PMOD shows a slight negative linear trend during the last three decades, while ACRIM shows a more complex 22-year cyclical trend: the average TSI value during solar cycle 22-23 (1991-2002) is higher than both averages during solar cycle 21-22 (1980-1991) and solar cycle (2002-2013) by approximately 0.5 W/m². Several phenomenological studies have found that the 11-year solar cycle induces a global surface temperature cycle with a peak-to-trough amplitude of about 0.1K , which is about three times larger than climate model predictions. Also, the thermal inertia of the climate system has a characteristic time of about τ=5-15 years. We show that under these thermodynamic circumstances the trend of the climate signature of these two composites strongly depends on the behavior of the TSI during the entire 20th century. By using different recent reconstruction of past solar activity we show that ACRIM would cause a global warming, while PMOD could both cause a warming or a cooling according to the value of the characteristic time response of the climate adopted in the simulations.
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1626 Global climate models (3337, 4928)
DE: 1650 Solar variability (7537)
DE: 4430 Complex systems
DE: 7538 Solar irradiance
SC: Global Environmental Change [GC]
MN: 2007 Fall Meeting