Lidar measurements of atmospheric lithium

Abstract

The Haute‐Provence Observatory (44° N, 6°E)lidar facility has been extended to study the atmospheric lithium and its isotopic ratio Li7/Li6 in the upper atmosphere. The experimental features have been improved in order to lower the detection limit to 3.105 cm−2 for the total abundance with a resolution of 1.2 km in the altitude profile. The night‐time measurements have been carried out from November 1977 to December 1979 and show some characteristic trends. The seasonal variation of the total abundance is similar to the one observed for sodium. The altitude profile is variable during the night. Total abundance fluctuations and peaks with small scale heights (1.5 km) are observed on numerous occasions. The layer is sensitive to high‐altitude artificial releases, like CAMEO in November 1978, and to impinging meteor showers. It is concluded that study of the behavior of atmospheric lithium and sodium should further our understanding of the alkali‐metals chemistry.

Lidar Soundings of the Mesospheric Nickel Layer Using Ni(3F) and Ni(3D) Transitions

“…Subsequently, resonance lidars have been used for active, altitude-resolved soundings (Bowman et al, 1969), and most recently, satellite-borne spectrometers, detecting scattered sunlight or nightglow, have provided a near global coverage (e.g., Gumbel et al, 2007). So far, the alkali metals, sodium, lithium, and potassium (e.g., Eska et al, 1998;Jegou et al, 1980;Qian & Gardner, 1995); the alkaline earth metals, calcium (e.g., Gerding et al, 2000;Granier et al, 1985) and magnesium (e.g., Correira et al, 2008;Langowski et al, 2015); and the transition metal, iron (e.g., Alpers et al, 1993;Bills & Gardner, 1990;Chu et al, 2011), have been investigated. The metal ions Ca + and Mg + have also been observed by ground-based lidar (e.g., Gerding et al, 2000) and from space (Langowski et al, 2015), respectively.…”

Sporadic Enhancement of the Mesospheric Sodium during the Perseids .GAMMA. Meteor Shower.

“…Enhancements of mesospheric sodium from permanent meteoric shower influxes have already been observed either by the photometric technique or the lidar technique (HAKE et al, 1972;MEGIE and BLAMONT, 1977). In addition to the enhancement of the sodium layer during meteor showers, the enhancement of lithium layer was already observed (JEGOU et al, 1980). It seems difficult to see such correlation by the photometric measurements at twilight because of the fast rise time and the relaxation time of the increase during meteor showers.…”

Resonance lidar system for mesospheric sodium measurements

“…Since then, resonance lidars have been used to study mesospheric metallic species other than Na, such as potassium, lithium, calcium in atomic and ionic form, and iron. [15][16][17][18][19] Measurements of atmospheric temperature from the Doppler broadening of the Na D 2 lines were made by Fricke and von Zahn 5 and She at al. 20 Later, She and Yu 21 presented an accurate method of determining the radial wind from the Na D 2 Doppler shift.…”