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Produced by both nature and human activities, sulfur dioxide (SO2) is an important species in the earth's atmosphere. SO2 has also been found in the atmospheres of other planets and satellites in the solar system. The photoabsorption cross sections and photodissociation of SO2 have been studied for several decades. In this paper, we reported the experimental results for photodissociation dynamics of SO2 via the G ̃ 1B1 state. By analyzing the images from the time-sliced velocity map ion imaging method, the vibrational state population distributions and anisotropy parameters were obtained for the O(1D2) + SO(X3Σ−, a1Δ, b1Σ+) and O(1S0) + SO(X3Σ−) channels, and the branching ratios for the channels O(1D2) + SO(X3Σ−), O(1D2) + SO(a1Δ), and O(1D2) + SO(b1Σ+) were determined to be ∼0.3, ∼0.6, and ∼0.1, respectively. The SO products were dominant in electronically and rovibrationally excited states, which may have yet unrecognized roles in the upper planetary atmosphere. [ABSTRACT FROM AUTHOR]

In geophysical hydrodynamics, baroclinic instability denotes the process in which the perturbations draw the energy from the mean flow potential power. Researchers focus their attention on the baroclinic instability in the Earth's atmosphere and oceans for the meteorological diagnosis and prediction. Under investigation in this paper is a repulsive nonlinear system modeling the marginally unstable baroclinic wave packets in a baroclinic flow. With respect to the amplitude of the baroclinic wave packet and correction to the mean flow resulting from the self-rectification of the baroclinic wave, we present a Lax pair with the changeable parameters and then derive the N-dark-dark soliton solutions, where N is a positive integer. Asymptotic analysis on the N-dark-dark solitons is processed to obtain the algebraic expressions of the N-dark-dark soliton components. We find that the obtained phase shift of each dark-dark soliton component is relevant with the N − 1 spectral parameters. Furthermore, we take N = 3 as an example and graphically illustrate the 3-dark-dark solitons, which are consistent with our asymptotic-analysis results. Our analysis may provide the explanations of the complex and variable natural mechanisms of the baroclinic instability. [ABSTRACT FROM AUTHOR]

We study and describe the reshaping of ultrashort and broadband mid-IR optical pulses in an ambient atmosphere. While all pulse propagation undergoes dispersion and absorption, which causes pulse reshaping, the effects are strongly pronounced for broadband radiation in the mid-IR due to the orders of magnitude greater oscillator strengths of molecular constituents of our atmosphere. A noticeable macroscopic impact is a transition of the measured autocorrelation function from squared hyperbolic secant to Lorentzian, which we fully explain based on pulse propagation, including molecular free induction decay. Electro-optical sampling directly reveals the light wave response to atmospheric molecular free induction decay, and a Kramers–Kronig-based propagation model thoroughly explains the observation. The findings are essential for applications in sensing, standoff detection, high-energy pulse propagation, and energy delivery. [ABSTRACT FROM AUTHOR]