Impact of Convective Gravity Waves on the Tropical Middle Atmosphere During the Madden-Julian Oscillation

Kalisch, S.,Kang, M.-J.,Chun, H.-Y. American Geophysical Union 2018 Journal of Geophysical Research: Atmospheres Vol.123 No.17

Tropical Gravity Wave Observations During the 2016 QBO Disruption

Silvio Kalisch,Hye-Yeong Chun 한국기상학회 2021 한국기상학회 학술대회 논문집 Vol.2021 No.10

In early 2016 equatorward propagating extratropical Rossby waves prominently caused a disruption of the quasi-biennial oscillation (QBO) - an until then unprecedented event. Recent studies (e.g. Kang et al. 2020) showed that equatorial planetary waves and small-scale gravity waves play an equally important role. Gravity waves, albeit known for their small horizontal and vertical characteristic wavelengths, can transport large amounts of energy and momentum from their tropospheric sources deep into the middle and upper atmosphere. However, global satellite observations of gravity waves generally remain challenging. In this presentation we will show results from remote-sensing satellite observations. We use observational data from NASA"s Atmospheric Infrared Sounder (AIRS) satellite instrument for our analysis. Variances of the 4.3 μm CO2 band brightness temperature are analysed to investigate the connection of gravity waves with the QBO disruption event. Spatial and temporal variations of gravity wave activity in the middle atmosphere are analysed for different regions in the tropics. Additionally, we use 8 μm brightness temperature data from AIRS to control our findings for deep convective activity. Our results show an increase in gravity wave variances during the QBO westerly phase prior the disruption with highest variances found in the pacific region. However, the Latin America region shows more prominent gravity wave activity in January and February 2016. The temporal correlation of this increased gravity wave activity with zonal winds were found highest at the 30 hPa level. We will further discuss potential implications of spatial gravity wave distributions to the development of the QBO disruption.

The Role of Gravity Waves During the QBO Disruption in 2016: A satellite perspective

Silvio Kalisch,Hye-Yeong Chun 한국기상학회 2021 한국기상학회 학술대회 논문집 Vol.2021 No.4

In February 2016, for the first time on record, the westerly phase of the QBO (quasi-biennial oscillation) was disrupted. This unprecedented event was prominently cause by equatorward propagating extratropical Rossby waves. Further studies (e.g. Kang et al. 2020) showed that equatorial planetary waves and small-scale gravity waves play an equally important role. Gravity waves in particular are known for their small horizontal and vertical characteristic wavelengths and can transport large amounts of energy and momentum from their tropospheric sources deep into the middle and upper atmosphere. In this study we will show results from remote-sensing satellite observations during the 2016 QBO disruption. We use observational data from NASA’s Atmospheric Infrared Sounder (AIRS) satellite instrument for our analysis. Variances of the 4.3 ㎛ CO₂ band brightness temperatures perturbations are analysed together with 8 ㎛ brightness temperature data to investigate the connection of gravity waves with the QBO disruption event. Spatial and temporal variations of gravity wave activity in the middle atmosphere are analysed for seven different regions in the tropics. The results show an increase in gravity wave variances during the QBO westerly phase prior the disruption with highest variances found in the pacific region. However, the Latin America region shows more prominent gravity wave activity in January and February 2016. We will further discuss potential implications of these spatial gravity wave distributions to the development of the QBO disruption.

Satellite Observations of Gravity Wave Activity During the Major Sudden Stratospheric Warming Event in 2009

Silvio Kalisch,Hye-Yeong Chun,Lars Hoffmann 한국기상학회 2020 한국기상학회 학술대회 논문집 Vol.2020 No.10

AIRS satellite observations of northern hemisphere gravity waves during the 2009 sudden stratospheric warming event

Silvio Kalisch,Hye-Yeong Chun 한국기상학회 2019 한국기상학회 학술대회 논문집 Vol.2019 No.10

Information Processing Styles of Nurse Managers and Staff Nurses

Beatrice J. Kalisch,Suzanne Begeny 한국간호과학회 2005 한국간호과학회 학술대회 Vol.2005 No.10

Current Research of East Asian Art History in Germany: Transmedia and Transcultural Discourses

Jeong-hee Lee-Kalisch 동악미술사학회 2017 東岳美術史學 Vol.0 No.21

The current research projects we have in the German language areas, presenting trends predominantly within the field of East Asian Art History, are concerned with transculturality and transmediality, with a transregional focus on the whole of Asia as well as on Africa and Europe. The application of the term “Transculture” has also produced many fashionable studies in Europe, such as »Global Art History«, »World Art History«, and »Horizontal Art History« and so on. As a result, most of these already mentioned institutions now offer curricula of art histories in global and transcultural contexts. Referring to my own three research topics as an example, I will try to define in which way the theoretical and methodological approaches can be understood in terms of transculturality and transmediality, and how we apply these in practical analysis: - Case study one: Transculturality in terms of transmedia practices from painting to photography in the age of modernity - Case study two: Transcultural processes of translation, appropriation and new interpretation as well as visual misunderstandings as an example of Buddhist art - Case study three: At the limits of transcultural theoretical applications, we utilize of “the eye of parallel seeing”. The aim of this talk is the defining the terms and its practice in more compact way: I could say, that the term transculturality can be understood as a phenomena or concept of meta and basic theory of cultural history, or art history in global context. Under the terms transmediality and translation I understand the approaching methods, which are used to explain the development processes and traces of transcultural phenomena. By using these methods we should find out who translates (actors of transculturalizing) and what (objects of transculture), where (transregional analysis), when (in global-historical context) in which way or how (transcultural practice) and why (anthropological analysis in transcultural, global context). The “parallel seeing” is also one of the comparative approaching methods for anthropological cultural studies on almost visual aesthetical level.

독일에서의 동아시아 미술사 연구 현황 : 매체간 그리고 문화간 담론들

Jeong-hee Lee-Kalisch 동악미술사학회 2017 東岳美術史學 Vol.0 No.21

The current research projects we have in the German language areas, presenting trends predominantly within the field of East Asian Art History, are concerned with transculturality and transmediality, with a transregional focus on the whole of Asia as well as on Africa and Europe. The application of the term “Transculture” has also produced many fashionable studies in Europe, such as »Global Art History«, »World Art History«, and »Horizontal Art History« and so on. As a result, most of these already mentioned institutions now offer curricula of art histories in global and transcultural contexts. Referring to my own three research topics as an example, I will try to define in which way the theoretical and methodological approaches can be understood in terms of transculturality and transmediality, and how we apply these in practical analysis: - Case study one: Transculturality in terms of transmedia practices from painting to photography in the age of modernity - Case study two: Transcultural processes of translation, appropriation and new interpretation as well as visual misunderstandings as an example of Buddhist art - Case study three: At the limits of transcultural theoretical applications, we utilize of “the eye of parallel seeing”. The aim of this talk is the defining the terms and its practice in more compact way: I could say, that the term transculturality can be understood as a phenomena or concept of meta and basic theory of cultural history, or art history in global context. Under the terms transmediality and translation I understand the approaching methods, which are used to explain the development processes and traces of transcultural phenomena. By using these methods we should find out who translates (actors of transculturalizing) and what (objects of transculture), where (transregional analysis), when (in global-historical context) in which way or how (transcultural practice) and why (anthropological analysis in transcultural, global context). The “parallel seeing” is also one of the comparative approaching methods for anthropological cultural studies on almost visual aesthetical level.

A comprehensive observational filter for satellite infrared limb sounding of gravity waves

Trinh, Q. T.,Kalisch, S.,Preusse, P.,Chun, H.-Y.,Eckermann, S. D.,Ern, M.,Riese, M. Copernicus GmbH 2015 Atmospheric measurement techniques Vol.8 No.3

<P><p><strong>Abstract.</strong> This paper describes a comprehensive observational filter for satellite infrared limb sounding of gravity waves. The filter considers instrument visibility and observation geometry with a high level of accuracy. It contains four main processes: visibility filter, projection of the wavelength on the tangent-point track, aliasing effect, and calculation of the observed vertical wavelength. The observation geometries of the SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) and HIRDLS (High Resolution Dynamics Limb Sounder) are mimicked. Gravity waves (GWs) simulated by coupling a convective GW source (CGWS) scheme and the gravity wave regional or global ray tracer (GROGRAT) are used as an example for applying the observational filter. Simulated spectra in terms of horizontal and vertical wave numbers (wavelengths) of gravity wave momentum flux (GWMF) are analyzed under the influence of the filter. We find that the most important processes, which have significant influence on the spectrum are the visibility filter (for both SABER and HIRDLS observation geometries) and aliasing for SABER and projection on tangent-point track for HIRDLS. The vertical wavelength distribution is mainly affected by the retrieval as part of the 'visibility filter' process. In addition, the short-horizontal-scale spectrum may be projected for some cases into a longer horizontal wavelength interval which originally was not populated. The filter largely reduces GWMF values of very short horizontal wavelength waves. The implications for interpreting observed data are discussed.</p> </P>

Tuning of a convective gravity wave source scheme based on HIRDLS observations

Trinh, Quang Thai,Kalisch, Silvio,Preusse, Peter,Ern, Manfred,Chun, Hye-Yeong,Eckermann, Stephen D.,Kang, Min-Jee,Riese, Martin Copernicus GmbH 2016 Atmospheric Chemistry and Physics Vol.16 No.11

<P>Abstract. Convection as one dominant source of atmospheric gravity waves (GWs) has been the focus of investigation over recent years. However, its spatial and temporal forcing scales are not well known. In this work we address this open issue by a systematic verification of free parameters of the Yonsei convective GW source scheme based on observations from the High Resolution Dynamics Limb Sounder (HIRDLS). The instrument can only see a limited portion of the gravity wave spectrum due to visibility effects and observation geometry. To allow for a meaningful comparison of simulated GWs to observations, a comprehensive filter, which mimics the instrument limitations, is applied to the simulated waves. By this approach, only long horizontal-scale convective GWs are addressed. Results show that spectrum, distribution of momentum flux, and zonal mean forcing of long horizontal-scale convective GWs can be successfully simulated by the superposition of three or four combinations of parameter sets reproducing the observed GW spectrum. These selected parameter sets are different for northern and southern summer. Although long horizontal-scale waves are only part of the full spectrum of convective GWs, the momentum flux of these waves is found to be significant and relevant for the driving of the QBO (quasi-biennial oscillation). The zonal momentum balance is considered in vertical cross sections of GW momentum flux (GWMF) and GW drag (GWD). Global maps of the horizontal distribution of GWMF are considered and consistency between simulated results and HIRDLS observations is found. The latitude dependence of the zonal phase speed spectrum of GWMF and its change with altitude is discussed. </P>