A coherence between the QBO and the amplitude of the Mauna Loa atmospheric transmission annual cycle

Abstract

The transmission of direct solar radiation through the atmosphere above Mauna Loa, Hawaii, is shown to have a quasibiennial cyclic component that is coherent with the well-known tropical stratospheric quasi-biennial oscillation (QBO). The QBO-related signal in the 32-year transmission record is manifested as an oscillation in the amplitude of the annual cycle. The transmission annual cycle is known to be caused by seasonal transport of Asian continental dust to and over the island of Hawaii. Variations in water vapour and ozone are eliminated as possible influences in the transmission-QBO re€ationship, leaving aerosols as the source of the oscillation. The ultimate cause for the quasi-biennial signal in the transmission record is unknown. Small but cyclic modifications to the tropospheric energy budget occur as a result of the transmission variations. The magnitude of the energy budget variations are less than those typically expected to have a significant climatic impact.

El Niño–Southern Oscillation correlated aerosol Ångström exponent anomaly over the tropical Pacific discovered in satellite measurements

“…It may involve complicated interaction between different processes, some of which may not have been considered. For example, some studies suggested possible correlation between aerosol properties and the QBO over the tropical Pacific [e.g., Dutton , 1991; Kane , 1994]. However, provided that satellite observations only became available in the past decade which has irregular ENSO cycles, the current record is too short to separate signals of different time scales, and to identify the source of the AE signal.…”

A wavelet-based spectral analysis of long-term time series of optical properties of aerosols obtained by lidar and radiometer measurements over an urban station in Western India

“…Tropospheric aerosols generally show annual and seasonal variability (Bodhaine et al, 1981). In addition to these characteristic oscillations in aerosols, Dutton (1992) reported a strong association between AO in atmospheric transmission factor (ATF) and QBO, and pointed out that the most likely candidate for the source of the QBO in the ATF time series is tropospheric aerosols of the size range 0.1 and 1 mm that scatters solar radiation.…”

Interannual variability of some trace elements and surface aerosol

“…Figure 8 shows a plot of the atmospheric transmission of the solar irradiance observed at MLO. These data have an annual cycle and their amplitude was reported to have a modulation in coherence with the well-known QBO of the equatorial stratospheric wind (Dutton, 1992). Here we check whether any QBO is seen in the deseasonalized data.…”