Solar flux and seasonal variations of the mesopause temperatures at 51°N

The influence of large-scale oscillations on long-term trend assessment in hydroxyl temperatures over Davis, Antarctica

“…It is assumed in Burns et al (2002a) that large-scale oscillations are averaged out in the large winter average window of 152 days. A smaller solar cycle dependence is reported compared to some other work, for example Shefov (1969) report a solar cycle dependence of ∼25 K=cycle for OH measurements over Zvenigorod (56 • N; 37 • E) and ∼20 K=cycle over Abastumani (42 • N; 43 • E), Sahai et al (1996) obtain an even larger 34 K=cycle for winter OH measurements over Calgary (53 • N; 114 • W), Labitzke and Chanin (1988) from rocket-sonde measurements over Heiss Island (81 • N; 58 • E) show a dependence of ∼25 K=cycle, L ubken and von Zahn (1991) obtain a dependence of ∼18 K=cycle for OH heights over Andenes (69 • N; 16 • E) and more recently Hernandez (2003) reports a ∼15 K=cycle (13 K=100 sfu) from Fabry-Perot spectrometer OH(6-2)P1(2) Doppler width measurements over South Pole (1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002), She et al (2002) see an equivalent e ect in sodium lidar (98:5 km) temperatures over Ft Collins (41 • N; 105 • W) and Gavrilyeva and Ammosov (2002) derive ∼13 K from IR spectrograph measurements over Maimaga station (63 • N, 129 • E) near Yakutsk. On the other hand Lowe (private communication) sees no more than a 2 K solar cycle dependence in 11 years of OH measurements over Delaware, Canada (43 • N; 81 • W) and Sigernes et al (2003) have also recently reported no signiÿcant solar cycle dependence in their 20 year OH temperature record over Adventdalen, Svalbard (78 • N; 15 • E).…”

“…Shefov, 1969;Myrabo, 1986;Sahai et al, 1996;Bittner et al, 2000) and long-term linear trends (e.g. Golitsyn et al, 1996;Semenov et al, 2002) in the OH layer, often from comparisons of annual averages derived for the whole, or large part, of each year.…”

Experimental evidence for solar cycle and long-term change in the low-latitude MLT region

“…With respect to solar cycle effects, Semenov (2000) has combined the OH data collected over several Russian stations covering the latitude band of 42-56 N and reports a positive solar response of 5:1 ðAE1:5Þ K per 100 solar flux units. Shorter series of OH rotational temperature measurements, made at several locations have mostly shown small or negligible trends (see, for example, Sahai et al, 1996;Reisin and Scheer, 2002;Burns, 2002;Espy and Stegman, 2002).…”

Mesospheric temperatures from observations of the hydroxyl (6–2) emission above Davis, Antarctica: A comparison of rotational and Doppler measurements

“…This approach has been used in a number of studies in both southern and northern hemispheres, and at a range of latitudes (e.g. Scheer and Reisen, 1990;Scheer et al, 1994;Takahashi et al, 1994;Sahai et al, 1996;Mulligan et al, 1996).…”