30 years of synoptic observations from Neumayer Station with links to datasets

High temporal resolution (three hours) records of temperature, wind speed and sea level pressure recorded at Antarctic research station Neumayer (70°S, 8°W) during 1982–2011 are analysed to identify oscillations from daily to intraseasonal timescales. The diurnal cycle dominates the three-hourly time series of temperature during the Antarctic summer and is almost absent during winter. In contrast, the three-hourly time series of wind speed and sea level pressure show a weak diurnal cycle. The dominant pattern of the intraseasonal variability of these quantities, which captures the out-of-phase variation of temperature and wind speed with sea level pressure, shows enhanced variability at timescales of ~ 40 days and ~ 80 days, respectively. Correlation and composite analysis reveal that these oscillations may be related to tropical intraseasonal oscillations via large-scale eastward propagating atmospheric circulation wave-trains. The second pattern of intraseasonal variability, which captures in-phase variations of temperature, wind and sea level pressure, shows enhanced variability at timescales of ~ 35, ~ 60 and ~ 120 days. These oscillations are attributed to the Southern Annular Mode/Antarctic Oscillation (SAM/AAO) which shows enhanced variability at these timescales. We argue that intraseasonal oscillations of tropical climate and SAM/AAO are related to distinct patterns of climate variables measured at Neumayer.本研究针对1982年至2011年间，南极诺伊迈尔（Neumayer）科考站（南纬70°，西经8°）获取的温度、风速与海平面气压的高时间分辨率（3小时间隔）观测记录展开分析，以识别日尺度至季节内尺度的振荡信号。南极夏季的3小时间隔温度时间序列以日循环为主要特征，而冬季则几乎不存在日循环信号。与之相对，风速与海平面气压的3小时间隔时间序列仅表现出微弱的日循环特征。上述气象要素的季节内变率主模态体现了温度、风速与海平面气压的反相变化特征，其变率在约40天与约80天的时间尺度上显著增强。相关分析与合成分析结果表明，此类振荡或通过大尺度向东传播的大气环流波列，与热带地区的季节内振荡存在关联。季节内变率的第二模态则体现了温度、风速与海平面气压的同相变化特征，其变率在约35天、约60天与约120天的时间尺度上显著增强。此类振荡可归因于南半球环状模（Southern Annular Mode, SAM）与南极涛动（Antarctic Oscillation, AAO），该类模态在上述时间尺度上存在显著增强的变率。本研究提出，热带气候的季节内振荡以及SAM/AAO，与诺伊迈尔科考站观测到的气候变量的差异化变率模态存在关联。