scholarly journals Multiscale interactions between monsoon intra-seasonal oscillations and low pressure systems that produce heavy rainfall events of different spatial extents

2021 ◽  
pp. 1-36
Author(s):  
Akshaya C Nikumbh ◽  
Arindam Chakraborty ◽  
G.S. Bhat ◽  
Dargan M. W. Frierson
Keyword(s):  
Large Scale ◽  
Thermodynamic Characteristics ◽  
Central India ◽  
Low Pressure ◽  
Monsoon Trough ◽  
The Other ◽  
Rainfall Events ◽  
Other Hand ◽  
Seasonal Oscillations ◽  
Low Pressure Systems

AbstractThe sub-seasonal and synoptic-scale variability of the Indian summer monsoon rainfall are controlled primarily by monsoon intra-seasonal oscillations (MISO) and low pressure systems (LPS), respectively. The positive and negative phases of MISO lead to alternate epochs of above-normal (active) and below-normal (break) spells of rainfall. LPSs are embedded within the different phases of MISO and are known to produce heavy precipitation events over central India. Whether the interaction with the MISO phases modulates the precipitation response of LPSs, and thereby the characteristics of extreme rainfall events (EREs) remains unaddressed in the available literature. In this study, we analyze the LPSs that produce EREs of various spatial extents viz., Small, Medium, and Large over central India from 1979 to 2012. We also compare them with the LPSs that pass through central India and do not give any ERE (LPS-noex). We find that thermodynamic characteristics of LPSs that trigger different spatial extents of EREs are similar. However, they show differences in their dynamic characteristics. The ERE producing LPSs are slower, moister and more intense than LPS-noex. The LPSs that lead to Medium and Large EREs tend to occur during the positive phase of MISO when an active monsoon trough is present over central India. On the other hand, LPS-noex and the LPSs that trigger Small EREs occur mainly during the neutral or negative phases of the MISO. The large-scale dynamic forcing, intensification of LPSs, and diabatic generation of low-level potential vorticity due to the presence of active monsoon trough help in the organization of convection and lead to Medium and Large EREs. On the other hand, the LPSs that form during the negative or neutral phases of MISO do not intensify much during their lifetime and trigger scattered convection, leading to EREs of small size.

scholarly journals Projected Changes in South Asian Monsoon Low Pressure Systems

2020 ◽  
Vol 33 (17) ◽  
pp. 7275-7287 ◽  
Author(s):  
Wenhao Dong ◽  
Yi Ming ◽  
V. Ramaswamy
Keyword(s):  
South Asian ◽  
Large Scale ◽  
Climate Model ◽  
Asian Summer Monsoon ◽  
Central India ◽  
Low Pressure ◽  
Geophysical Fluid Dynamics Laboratory ◽  
South Asian Summer Monsoon ◽  
Projected Changes ◽  
Low Pressure Systems

AbstractMonsoon low pressure systems (MLPSs) are among the most important synoptic-scale disturbances of the South Asian summer monsoon. Potential changes in their characteristics in a warmer climate would have broad societal impacts. Yet, the findings from a few existing studies are inconclusive. We use the Geophysical Fluid Dynamics Laboratory (GFDL) coupled climate model CM4.0 to examine the projected changes in the simulated MLPS activity under a future emission scenario. It is shown that CM4.0 can skillfully simulate the number, genesis location, intensity, and lifetime of MLPSs. Global warming gives rise to a significant decrease in MLPS activity. An analysis of several large-scale environmental variables, both dynamic and thermodynamic, suggests that the decrease in MLPS activity can be attributed mainly to a reduction in low-level relative vorticity over the core genesis region. The decreased vorticity is consistent with weaker large-scale ascent, which leads to less vorticity production through the stretching term in the vorticity equation. Assuming a fixed radius of influence, the projected reduction in MLPSs would significantly lower the associated precipitation over north-central India, despite an overall increase in mean precipitation.

scholarly journals Performance of Adenosine Deaminase assay in diagnosis of pulmonary & extrapulmonary tuberculosis

2021 ◽  
Author(s):  
Anuja N Mulmule ◽  
Arti R Mishra ◽  
Vinita R Hutke ◽  
Seema D Shekhawat ◽  
Amit R Nayak ◽  
...  
Keyword(s):  
Adenosine Deaminase ◽  
Large Scale ◽  
Extrapulmonary Tuberculosis ◽  
Central India ◽  
Abdominal Tuberculosis ◽  
The Other ◽  
Clinical Samples ◽  
Other Hand ◽  
Study Results

Adenosine Deaminase (ADA) estimation in all forms of tuberculosis (TB) is done by several investigators, however, there has been a lot of debate about the use of the ADA for TB diagnosis. In the present study, to overcome this debate, we have planned a large scale study in the Central India population for all forms of TB i.e. pulmonary TB (PTB), tuberculous meningitis (TBM), TB arthritis (TBAR), and abdominal tuberculosis (ATB) to access the performance of ADA for diagnosis of TB. In addition to that, we have also studied the performance of the ADA test in the prognosis of TB. ADA activity was evaluated using the method of Guisti and Galanti. To evaluate the role of the ADA test as a prognostic marker in TB, we have collected follow-up clinical samples of PTB and TBM cases. The sensitivity of the ADA test is impressive in all forms of TB clinical samples analyzed for the study (PTB [82%], TBM [85%] TBAR [85%]), and (ATB) [84%]. However, the specificity was variable as ADA test results were found to be satisfactory for extrapulmonary TB (EPTB) cases ( i.e TBM [89%], (ATB) [88%], TBAR [88%]), on the other hand, poor specificity was observed in PTB cases (PTB [48%]). In the follow-up clinical samples (collected before and after anti-TB treatment [ATT]). In the follow-up samples, the result of the ADA test was observed to have declined drastically thereby showing a negative value after the ATT. Our study, which consists of a large number of samples, suggests that the ADA has very limited value in the diagnosis of PTB, and hence it is not recommended for PTB diagnosis. On the other hand, the ADA test is found to be useful for the diagnosis of EPTB in correlation to the patient's clinical condition. Along with the above-mentioned aspects and according to our follow-up study results, we recommend that ADA be useful as a prognostic indicator for TB.

An investigation of the bias in the median track of Monsoon Low Pressure Systems over the Indian subcontinent in CESM1.2.2 simulations

2021 ◽  
Author(s):  
Tresa Mary Thomas ◽  
Govindasamy Bala ◽  
Venkata Vemavarapu Srinivas
Keyword(s):  
Monsoon Rainfall ◽  
Indian Subcontinent ◽  
Low Pressure ◽  
Monsoon Trough ◽  
Tropospheric Temperature ◽  
Monsoon Period ◽  
Global Circulation Models ◽  
Extreme Precipitation Events ◽  
Latitudinal Shift ◽  
Low Pressure Systems

<p>Monsoon low pressure systems (LPS) are synoptic scale tropical disturbances that form in the Indian subcontinent over the quasi-stationary monsoon trough axis during the monsoon period (June to September). In a recent study, we showed that 60-70% of monsoon rainfall and 78% of extreme precipitation events in India are associated with LPS. Global circulation models (GCMs) have been used to understand the behavior of tropical disturbances in the past. It has been found that model resolution plays a key role in simulating the climatology of tropical storms, with finer resolution (of the order of 20-100km) required to better represent the genesis and propagation of these storms. As GCMs can be run at these finer resolutions today, various characteristics of LPS in the Indian subcontinent can be studied. It has been found that most CMIP5 GCMs show a southward latitudinal shift in the monsoon trough location and hence in the LPS tracks and associated characteristics. This shift has been attributed to a weaker simulated meridional tropospheric temperature gradient (MTG) in the models. However, the cause of weaker MTG in models is not known. In this study, we investigate the reason for the weaker MTG and hence the southward latitudinal shift of LPS tracks in the Climate Earth System Model (CESM1.2.2). A present-day control simulation is performed at 0.9°×1.25° horizontal resolution, and output is saved at 6-hourly intervals for LPS track analysis. We find that CESM is capable of simulating the general behavior of monsoon over the Indian subcontinent in terms of seasonality, propagation of monsoon rainfall, and mean monsoon winds. LPS are tracked in the CESM outputs by our recently proposed Automated Tracking Algorithm using Geopotential Criteria (ATAGC). A southward latitudinal shift is observed in the median track of LPS in CESM present-day simulations. The value of MTG is also significantly smaller compared to the observed MTG. The results from investigations on the likely causes for the weaker MTG in CESM will be presented at the meeting.</p>

scholarly journals The Theory of the Large Scale Structure of the Universe

1978 ◽  
Vol 79 ◽  
pp. 409-421 ◽  
Author(s):  
Ya B. Zeldovich
Keyword(s):  
Early Childhood ◽  
Sigmund Freud ◽  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
The Other ◽  
Childhood Experiences ◽  
Other Hand ◽  
The Universe ◽  
Single Statement

The God-father of psychoanalysis Professor Sigmund Freud taught us that the behaviour of adults depends on their early childhood experiences. in the same spirit, the problem of cosmological analysis is to derive the observed present day situation and structure of the Universe from certain plausible assumptions about its early behaviour. Perhaps the most important single statement about the large scale structure is that there is no structure at all on the largest scale − 1000 Mpc and more. On this scale the Universe is rather uniform, structureless and isotropically expanding - just according to the simplified pictures of Einstein-Friedmann……. Humason, Hubble…. Robertson, Walker. On the other hand there is a lot of structure on the scale of 100 or 50 Mpc and less. There are clusters and superclusters of galaxies.

scholarly journals Adult caddisflies (Trichoptera) attracted to artificial lights in the middle reaches of the Shinano River from 2005 to 2007

Zoosymposia ◽  
2011 ◽  
Vol 5 (1) ◽  
pp. 143-146 ◽  
Author(s):  
KIMIO HIRABAYASHI ◽  
GORO KIMURA ◽  
EISO INOUE
Keyword(s):  
Species Composition ◽  
Air Temperature ◽  
Large Scale ◽  
Abundant Species ◽  
The Other ◽  
Seasonal Abundance ◽  
Other Hand ◽  
The Mean ◽  
Summer Flood

The species composition and abundance of adult caddisflies attracted to the illuminated showcase of a vending machine set along the middle reaches of the Shinano River were investigated every Sunday night from April to November in 2005 to 2007. A total of 1,405 adult caddisflies was collected during the investigation periods. We identified a total of 13 species belonging to 11 genera of 8 families. The most abundant species was Psychomyia acutipennis (Ulmer 1908) each year. Psychomyia acutipennis adults were collected from mid-May to the beginning of October (the range of mean air temperature was 13.8 to 27.7°C), with its seasonal abundance divided into several peaks, i.e., the end of May, the beginning of June, and the end of August to the beginning of September in both 2006 and 2007. On the other hand, in 2005 when there was no large-scale summer flood and there were no marked abundance peaks. The present study suggests that the mean air temperature and summer floods impacted the seasonal abundance of P. acutipennis adults.

scholarly journals The Bologna submillisecond pulsar survey

2000 ◽  
Vol 177 ◽  
pp. 27-30 ◽  
Author(s):  
Nichi D’Amico
Keyword(s):  
Neutron Star ◽  
Large Scale ◽  
Equations Of State ◽  
The Other ◽  
Millisecond Pulsar ◽  
Millisecond Pulsars ◽  
Spin Period ◽  
Other Hand

AbstractSince the discovery of the original millisecond pulsar, no pulsars with a shorter spin period (P<1.56 ms) were found. However, according to the most popular equations of state, the theoretical limiting spin period of a neutron star can be much shorter. On the other hand, most of the large scale searches for millisecond pulsars carried out so far were strongly biased against the detection of ultrashort periodicities. In this paper we describe a new large scale pulsar survey with a minimum detectable period much shorter than previous searches.

scholarly journals II. On the stratification of vesicular ice by pressure

1859 ◽  
Vol 9 ◽  
pp. 209-213
Keyword(s):  
Melting Temperature ◽  
Large Scale ◽  
Freezing Point ◽  
The Other ◽  
Bounding Surface ◽  
Effect Of Pressure ◽  
Other Hand ◽  
Continuous Mass ◽  
Two Sides

In my last letter to you I pointed out that my brother’s theory of the effect of pressure in lowering the freezing-point of water, affords a perfect explanation of various remarkable phenomena involving the internal melting of ice, described by Professor Tyndall in the Number of the ‘Proceedings’ which has just been published. I wish now to show that the stratification of vesicular ice by pressure observed on a large scale in glaciers, and the lamination of clear ice described by Dr. Tyndall as produced in hand specimens by a Brahmah’s press, are also demonstrable as conclusions from the same theory. Conceive a continuous mass of ice, with vesicles containing either air or water distributed through it ; and let this mass be pressed together by opposing forces on two opposite sides of it. The vesi­cles will gradually become arranged in strata perpendicular to the lines of pressure, because of the melting of ice in the localities of greatest pressure and the regelation of the water in the localities of least pressure, in the neighbourhood of groups of these cavities . For, any two vesicles nearly in the direction of the condensation will afford to the ice between them a relief from pressure, and will occa­sion an aggravated pressure in the ice round each of them in the places farthest out from the line joining their centres; while the pressure in the ice on the far sides of the two vesicles will be some­ what diminished from what it would be were their cavities filled up with the' solid, although not nearly as much diminished as it is in the ice between the two. Hence, as demonstrated by my brother’s theory and my own experiment, the melting temperature of the ice round each vesicle will be highest on its side nearest to the other vesicle, and lowest in the localities on the whole farthest from the line joining the centres. Therefore, ice will melt from these last-mentioned localities, and, if each vesicle have water in it, the partition between the two will thicken by freezing on each side of it. Any two vesicles, on the other hand, which are nearly in a line per­pendicular to the direction of pressure will agree in leaving an aggra­vated pressure to be borne by the solid between them, and will each direct away some of the pressure from the portions of the solid next itself on the two sides farthest from the plane through the centres, perpendicular to the line of pressure. This will give rise to an in­ crease of pressure on the whole in the solid all round the two cavi­ties, and nearly in the plane perpendicular to the pressure, although nowhere else so much as in the part between them. Hence these two vesicles will gradually extend towards one another by the melting of the intervening ice, and each will become flattened in towards the plane through the centres perpendicular to the direction of press­ure, by the freezing of water on the parts of the bounding surface farthest from this plane. It may be similarly shown that two vesi­cles in a line oblique to that of condensation will give rise to such variations of pressure in the solid in their neighbourhood, as to make them, by melting and freezing, to extend, each obliquely towards the other and from the parts of its boundary most remote from a plane midway between them, perpendicular to the direction of pressure.

Resisting (Meta) Physical Catastrophes through Acts of Marronage

2020 ◽  
Vol 23 (1) ◽  
pp. 35-57
Author(s):  
Pedro Lebrón Ortiz ◽  
Keyword(s):  
Puerto Rican ◽  
Large Scale ◽  
The Other ◽  
Other Hand ◽  
The One

The colonial process constituted a twofold catastrophe. On the one hand, the genocide and enslavement of racialized bodies, along with the large-scale destruction of their lands was a material, or physical, catastrophe. On the other hand, colonialism led to a reconfiguring of intersubjectivities which constituted a “metaphysical catastrophe” according Puerto Rican philosopher Nelson Maldonado-Torres. This metaphysical catastrophe relegates the racialized subject beneath the zones of being and non-being leading to dehumanization and permanent war. This text intends to illuminate ways in which analectical marronage, as an existential state of Being, resists this twofold catastrophe brought about by the imperial enterprise.

Simulation of Monsoon trough and low pressure systems in CMIP6 models

2020 ◽  
Author(s):  
Praveen Veluthedathekuzhiyil ◽  
Ajayamohan Ravindran ◽  
Sabeerali Cherumadanakadan Thelliyil
Keyword(s):  
Climate Models ◽  
Monsoon Rainfall ◽  
Indian Monsoon ◽  
Low Pressure ◽  
Monsoon Trough ◽  
Warming Scenario ◽  
Wide Range ◽  
Future Warming ◽  
Dynamical Features ◽  
Low Pressure Systems

<p>Monsoon low pressure systems (LPS) contributes to more than half of the Indian monsoon rainfall. However most climate models fail to capture the characteristics of low pressure systems realistically. This aspect is scrutinized in a wide range of available CMIP6 model simulations using an objective LPS tracking algorithm. Broader features such as monsoon trough over which these systems forms are also analyzed. It has been found that, majority of the models fail to realistically represent these two important features. However few models that were able to capture these events in CMIP5 are able to simulate them in CMIP6 as well. We examine the dynamical features that lead to realistic simulation of LPS in these set of models. Selected good models are then used to study the characteristics of LPS in a future warming scenario. This study will help in judging the performance of models and for any future improvements.</p>

scholarly journals Concertante techniques in Trois images by Ivo Petrić

2001 ◽  
Vol 37 (1) ◽  
pp. 103-112
Author(s):  
Niall O'Loughlin
Keyword(s):  
20Th Century ◽  
Large Scale ◽  
The Other ◽  
Violin Concerto ◽  
Avant Garde ◽  
Other Hand ◽  
The One ◽  
The Individual ◽  
Frank Martin ◽  
Movement Structure

The large-scale romantic concerto has been reevaluated by many composers of the 20th century. These have included Stravinsky, Honegger and Frank Martin, who have all tended to compose on a much smaller scale. One such work is Ivo Petrić's Trois images, a violin concerto dating from 1972-73. It displays an ambiguous approach to form, the relationships between the soloist and orchestra, the use of musical motives and the idea of the concerto. On the one hand, it has links with tradition in that it uses the title and three-movement structure of the concerto, the traditional relationships of dialogue, solo and accompaniment, development of motives and virtuoso techniques. On the other hand, it breaks with tradition by disguising the contrasts and separation of the individual movements, and transforming traditional concerto techniques for use in the freely coordinated idiom that the composer was using at the time. It proves to be an excellent example of how concerto techniques can be combined with the techniques of the avant-garde.

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