On tidal variability and the existence of planetary wave-like oscillations in the upper thermosphere—II. Non-linear interactions and global scale oscillations

Abstract. FORMOSAT-3/COSMIC temperature data during 2009 to 2010 are analysed for tides in the middle atmosphere from ~ 10 to 50 km. COSMIC is a set of six micro satellites in near sun synchronous orbits with 30° orbital separations and provides good phase space sampling of tides. Short term tidal variability is deduced by considering ± 10 days' data together. The DW1 tide is found to peak over the equator at 30 km. It maximises and slightly shifts poleward during winters and thus is attributed to ozone absorption. Over mid and high latitudes, DW1 and the non-migrating tides DS0 and DW2 are intermittent in nature. Numerical experiments in the current study show that these could be a result of aliasing as they are found to occur at times of steep rise or fall in the mean temperature, particularly during the SSW of 2010. Further, stationary planetary wave components are found to be of very large amplitudes in the northern hemispheres reaching 18 K at 30 km over 65° N. By using data from COSMIC over shorter durations, aliasing between SPW and non-migrating tides is reduced and thus results in the large amplitudes of the former. This study clearly indicates that non-linear interactions are not a very important source of generation of the non migrating tides in the high latitude winter hemisphere. There is also a modulation of SPW1 by ~ 60 days in the high latitudes, which was not seen earlier.

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Migrating and non-migrating tides observed in the stratosphere from FORMOSAT-3/COSMIC temperature retrievals

Annales Geophysicae ◽

10.5194/angeo-38-421-2020 ◽

2020 ◽

Vol 38 (2) ◽

pp. 421-435 ◽

Cited By ~ 1

Author(s):

Uma Das ◽

William E. Ward ◽

Chen Jeih Pan ◽

Sanat Kumar Das

Keyword(s):

Planetary Wave ◽

Middle Atmosphere ◽

High Latitudes ◽

Sudden Stratospheric Warming ◽

Short Term ◽

The Mean ◽

Tidal Variability ◽

Using Data ◽

Stationary Planetary Wave ◽

Linear Interactions

Abstract. Formosa Satellite-3 and Constellation Observing System for Meteorology, Ionosphere and Climate (FORMOSAT-3/COSMIC) temperature data during October 2009–December 2010 are analysed for tides in the middle atmosphere from ∼10 to 50 km. COSMIC is a set of six micro-satellites in near-Sun-synchronous orbits with 30∘ orbital separations that provides good phase space sampling of tides. Short-term tidal variability is deduced by considering ±10 d data together. The migrating diurnal (DW1) tide is found to peak over the Equator at 30 km. It maximises and slightly shifts poleward during winters. Over middle and high latitudes, DW1 and the non-migrating diurnal tides with wavenumber 0 (DS0) and wavenumber 2 (DW2) are intermittent in nature. Numerical experiments in the current study show that these could be a result of aliasing as they are found to occur at times of a steep rise or fall in the mean temperature, particularly during the sudden stratospheric warming (SSW) of 2010. Further, the stationary planetary wave component of wavenumber 1 (SPW1) is found to be of very large amplitudes in the Northern Hemisphere, reaching 18 K at 30 km over 65∘ N. By using data from COSMIC over shorter durations, it is shown that aliasing between stationary planetary wave and non-migrating tides is reduced and thus results in the large amplitudes of the former. This study clearly indicates that non-linear interactions are not a very important source for the generation of non-migrating tides in the middle- and high-latitude winter stratosphere. There is also a modulation of SPW1 by a ∼60 d oscillation in the high latitudes, which was not seen earlier.

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Internal GIG Ecosystem in IT/ITeS Organisations for Non-linear Growth

South Asian Journal of Human Resources Management ◽

10.1177/23220937211013266 ◽

2021 ◽

pp. 232209372110132

Author(s):

Debolina Dutta ◽

Prem Mirchandani ◽

K. P. Anasha

Keyword(s):

Employee Satisfaction ◽

Linear Growth ◽

Growth Models ◽

Global Scale ◽

Growth Trajectory ◽

It Services ◽

Industry Growth ◽

It Service ◽

Significant Contributor ◽

Non Linear

The Indian IT/ITeS industry is a significant contributor to India’s GDP and has had an impressive growth trajectory. However, it continues to be plagued with talent shortages, managing employee satisfaction, growth aspirations and reducing attrition. COVID-19 has presented an unprecedented opportunity for IT service organisations to transform the established paradigm of working. The industry has been exploring non-linear growth models that address the talent demand-supply gap. With skilled talent shortage continuing to limit the industry growth, non-linear initiatives of growth are urgently required. We propose a model of ‘Internal Gig’ worker (I-GIG) for the IT services industry. The new I-GIG workforce would be providing non-linear outcomes without increasing costs significantly. We also argue that this model would be motivational for employees who opt for it, with commensurate reward motivations to engage them. Additionally, this model would enable the workanywhere, anytime and leverage talent availability on a global scale.

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