On the response of Halogen Occultation Experiment (HALOE) stratospheric ozone and temperature to the 11‐year solar cycle forcing

Abstract

[1] Results are presented on responses in 14-year (1991-2005) time series of stratospheric ozone and temperature from the Halogen Occultation Experiment (HALOE) of the Upper Atmosphere Research Satellite (UARS) to a solar cycle (SC-like) variation. The ozone time series are for ten, 20-degree-wide, latitude bins from 45°S to 45°N and for thirteen ''half-Umkehr'' layers of about 2.5 km thickness and extending from 63 hPa to 0.7 hPa. The temperature time series analyses were restricted to pressure levels in the range of 2 hPa to 0.7 hPa. Multiple linear regression (MLR) techniques were applied to each of the 130 time series of bin-averaged, sunrise plus sunset ozone points over that latitude/pressure domain. A simple, 11-year periodic term and a linear trend term were added to the final MLR models after their seasonal and interannual terms had been determined. Where the amplitudes of the 11-year terms are significant, they are in phase with those of the more standard proxies for the solar UV flux. The maximum minus minimum response for ozone is on the order of 2 to 3% from about 2 to 5 hPa and for the latitudes of 45°S to 45°N. There is also a significant maximum minus minimum response on the order of 1 K for temperature between 15°S and 15°N and from 2 to 0.7 hPa. The associated linear trends for ozone are near zero in the upper stratosphere. It is noted, however, that effects of the changes in total chlorine during this 14-year period were not accounted for explicitly and that their omission can be a confounding effect for both the analyzed solar cycle responses and the linear terms, especially for tropical upper stratospheric ozone. It is concluded that the solar occultation technique of HALOE provided adequate sampling and sufficient vertical resolution for obtaining the solar cycle response in stratospheric ozone.

Methane as a diagnostic tracer of changes in the Brewer–Dobson circulation of the stratosphere

“…Points for the data time series of the present study are generated using the HALOE version 19, Level 2 CH 4 profiles from occurrences of the HALOE SR or SS observations within a latitude zone for 1992-2005, as in Remsberg (2008). The SR and SS profiles are binned into 14 overlapping lati- tude zones from 65 • S to 65 • N and at 12 pressure altitudes, giving a total of 168 separate time series for analysis.…”

On the ambiguous nature of the 11 year solar cycle signal in upper stratospheric ozone

“…An analysis of another high-quality, but relatively short (1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005), satellite data set from the Halogen Occultation Experiment (HALOE) instrument also shows a double-peaked SCS, but the primary peak is shifted upward to the mid stratosphere (35 km altitude) with a second peak in the lower mesosphere [e.g., Remsberg, 2008]. Also, HALOE data do not show any significant ozone SCS in the upper stratosphere (~45 km).…”

Climate responses to SATIRE and SIM-based spectral solar forcing in a 3D atmosphere-ocean coupled GCM

“…The temperature response is more sensitive in the upper stratosphere (2 mb) than in the middle stratosphere (15 mb), by a factor of two for both solar forcing scenarios. The warming in the upper stratosphere is closely related to the UV irradiance changes, and this feature is visible from the observations and many model studies (e.g., Frame & Gray 2010;Remsberg 2008). The sensitivity parameters (i.e., b in Eq.…”

“…Using Halogen Occultation Experiment (HALOE) observations from 1991 to 2005, Remsberg (2008) found maximum ozone response on the order of 2-3% in the upper stratosphere at subtropical to middle latitudes. The average response to SATIRE forcing is about a half of HALOE observed response, whereas the average response to SIM-based forcing is about a factor of two of the observed ozone change.…”

“…8 in that study) except larger response and higher altitude of the peak for SIM-based forcing in this study. Observations from HALOE (peak value of~1°C at~1 mb) (Remsberg 2008) suggest that the response to SATIRE forcing underestimates the temperature changes, whereas response to SIM-based forcing overestimates the temperature changes by a factor of two with a peak a higher altitude.…”