scholarly journals Energetics of the lower tropospheric eddies in wave number domain during northern summer monsoon

MAUSAM ◽  
2021 ◽  
Vol 51 (2) ◽  
pp. 119-126
Author(s):  
S. M. BAWISKAR ◽  
M. D. CHIPADE ◽  
S. S. SINGH
Keyword(s):  
Kinetic Energy ◽  
Summer Monsoon ◽  
Standing Waves ◽  
Wave Number ◽  
Tropical Region ◽  
Data Set ◽  
Tropical Regions ◽  
Northern Summer ◽  
Energy Processes ◽  
The Waves

Lower tropospheric energetics and energy processes of zonal waves for three consecutive northern summer monsoon seasons of 1994, 1995 and 1996 are presented. Fourier technique is used. The features of the tropical and extra-tropical regions are very well reflected by the data set used for this study. The results do not show marked year to year variations in the pattern of energy processes. The character of energy processes differs significantly from one latitudinal region to other. Wave to zonal mean flow interactions and wave to wave interactions are almost opposite in character over R1 (10° S -10° N) and R2 (10° N -30° N). L (n) interaction indicates that R1 acts as source of kinetic energy to the waves over R2. Particularly, standing waves I and 2 over RI are the major source of kinetic energy to the waves over R2. Extra-tropical region R3 (30° N -50° N) is dominated by transient waves while tropical regions R1 and R2 are dominated by standing waves. Medium and short waves have significant contributions over extra-tropical region whereas tropical regions are dominated by long waves. The pattern of energy processes over R3 is somewhat similar to the energy processes over R1. This is because both the regions have anti-cyclonic lateral shear.

scholarly journals Upper tropospheric energetics of standing eddies In wave number domain during contrasting Monsoon activity over India

MAUSAM ◽  
2021 ◽  
Vol 43 (4) ◽  
pp. 403-410
Author(s):  
S.S. BAWISKAR ◽  
S.M. SINGH
Keyword(s):  
Energy Source ◽  
Kinetic Energy ◽  
Interaction Analysis ◽  
Standing Waves ◽  
Wave Interaction ◽  
Wave Number ◽  
Mean Flow ◽  
S Wave ◽  
Flow Interaction ◽  
Energy Equations

The upper tropospheric energetics of the standing eddies in wave number domain during contrasting monsoon' activity over India have been investigated. Two normal monsoon years (1970. 1971) and two drought monsoon years (1972, 1979) are considered for a comparative study, Energy equations of Saltzman (1957) are used to compute wave-wave Interaction and wave to zonal mean flow Interaction. Analysis of the results show that the standing eddies in the region of tropical easterlies (5°S-24 .2°N) have larger kinetic energy than those in the region of southern hemispheric, westerlies (24.2°S-5°S). Wave to zonal mean flow interaction of all waves (waves 1-15) Indicate that the standing eddies are a source of kinetic energy to zonal mean flow ID the region of easterlies and there sink of kinetic energy to zonal mean flow in the region of westerlies. In the region of easterlies planetary standing waves (waves 1-2) are the major kinetic energy source to other standing waves and wave-wave Interaction of all waves leads to positive Imbalance of kinetic energy during normal monsoon years (1970, 1971) and negative imbalance, of kinetic, energy during drought monsoon years (1972, 19~9). In the region of westerlies the imbalance of kinetic energy IS negative during normal monsoon years and positive during drought monsoon years.

Cross-equatorial dry intrusions and their impact on Indian summer monsoon-associated water cycle

2020 ◽  
Author(s):  
Deepika Rai ◽  
Shira Raveh-Rubin
Keyword(s):  
Summer Monsoon ◽  
Indian Summer Monsoon ◽  
Water Cycle ◽  
Sensible Heat Flux ◽  
Atmospheric Stability ◽  
Lower Troposphere ◽  
Surface Fluxes ◽  
Annual Rainfall ◽  
Tropical Region ◽  
Tropical Regions

<p>Dry intrusion (DI) is the slantwise descent of dry air from the extratropical upper troposphere to the mid/lower troposphere of the lower latitudes. When reaching the tropical regions, DIs substantially change the overall amount of available moisture, ocean surface fluxes into the atmosphere, as well as the atmospheric stability to vertical motion and the 3-dimensional flow and associated dynamics. However, the occurrence of such events has not been quantified systematically. Here, we quantify the climatological occurrence of DIs that extend from the extratropics to tropical regions. Specifically, we focus on events that host subsequent cross-equatorial flow. Using 6-hourly ERA-Interim reanalysis data with a Lagrangian approach, we show that during the summer monsoon season (June to September) DIs enter the tropical region from the southern hemisphere with peaks that exceed 10 % frequency in time. DI arrival into the tropics is associated with dry and cold lower-tropospheric anomalies, and consequently induced ocean evaporation and sensible heat flux into the atmosphere. Although cross-equatorial DIs are rare, a hotspot of such DIs is evident in the Indian Ocean, having a potential role for Indian summer monsoon (ISM) water cycle. The dominance of the ISM for the annual rainfall over India implies that small changes in the evaporation and moisture pathways may influence the ISM precipitation downstream significantly. Indeed, we demonstrate the connection between ISM rainfall and the preceding water-cycle interaction under DI conditions, and further show that DIs entering the Indian subcontinent modify the low-level jets. </p>

scholarly journals Estimation of the annual rainfall erosivity index based on hourly rainfall data in a tropical region

2020 ◽  
Author(s):  
Ming-Hsi Lee ◽  
I-Ping Hsu
Keyword(s):  
Kinetic Energy ◽  
Soil Loss ◽  
Rainfall Intensity ◽  
Rainfall Data ◽  
Annual Rainfall ◽  
Tropical Region ◽  
Rainfall Erosivity ◽  
Data Set ◽  
Data Accumulation ◽  
Hourly Rainfall

The annual mean rainfall erosivity (R) indicates the potential soil loss caused by the precipitation and runoff and is used to predict the soil loss from agricultural hillslopes. R is calculated from rainfall stations with continuously recording rainfall databases. However, many short-term real-time rainfall databases that also relate to the rainfall intensity are not readily available around Taiwan, with the hourly rainfall data being predominantly available. The annual mean rainfall erosivity calculated by the 10-min rainfall data accumulation converted to the 30-min rainfall data (R<sub>10_30</sub>) can be estimated using the annual mean rainfall erosivity calculated by the 10-min rainfall data accumulation convert to the hourly rainfall data (R<sub>10_60</sub>) that are calculated from the kinetic energy calculated by the 10-min rainfall data accumulation converted to the hourly rainfall data (E<sub>60j</sub>). The maximum 60-min rainfall intensity calculated by the 10-min rainfall data accumulation converted to the hourly rainfall data (I<sub>60j</sub>) has been established in rainfall stations throughout southern Taiwan. The 10-min rainfall data set consists of 15 221 storm events from 2002 to 2017 monitored by 51 rainfall stations located in the tropical regions in Taiwan. According to the results of this study, the average conversion factors of the kinetic energy (1.04), rainfall erosivity (1.47), and annual mean rainfall erosivity (1.30) could be estimated based on the 10-min rainfall data.

scholarly journals Validation of the HIRHAM-Simulated Indian Summer Monsoon Circulation

2010 ◽  
Vol 2010 ◽  
pp. 1-14 ◽  
Author(s):  
Stefan Polanski ◽  
Annette Rinke ◽  
Klaus Dethloff
Keyword(s):  
Summer Monsoon ◽  
Climate Model ◽  
Regional Climate ◽  
Horizontal Resolution ◽  
Monsoon Circulation ◽  
Data Sets ◽  
Data Set ◽  
Topographic Features ◽  
Temperature And Precipitation ◽  
Simulated Precipitation

The regional climate model HIRHAM has been applied over the Asian continent to simulate the Indian monsoon circulation under present-day conditions. The model is driven at the lateral and lower boundaries by European reanalysis (ERA40) data for the period from 1958 to 2001. Simulations with a horizontal resolution of 50 km are carried out to analyze the regional monsoon patterns. The focus in this paper is on the validation of the long-term summer monsoon climatology and its variability concerning circulation, temperature, and precipitation. Additionally, the monsoonal behavior in simulations for wet and dry years has been investigated and compared against several observational data sets. The results successfully reproduce the observations due to a realistic reproduction of topographic features. The simulated precipitation shows a better agreement with a high-resolution gridded precipitation data set over the central land areas of India and in the higher elevated Tibetan and Himalayan regions than ERA40.

scholarly journals An Analysis of the Energetics of Tropical and Extra-Tropical Regions for Warm ENSO Composite Episodes

2017 ◽  
Vol 32 (1) ◽  
pp. 39-51
Author(s):  
Zayra Christine Sátyro ◽  
José Veiga
Keyword(s):  
Kinetic Energy ◽  
Potential Energy ◽  
El Niño ◽  
Energy Production ◽  
El Nino ◽  
Southern Oscillation ◽  
Stable Condition ◽  
The Other ◽  
Tropical Regions ◽  
Using Data

Abstract This study focuses on the quantification and evaluation of the effects of ENSO (El Niño Southern Oscillation) warm phases, using a composite of five intense El Niño episodes between 1979 – 2011 on the Energetic Lorenz Cycle for four distinct regions around the globe: 80° S – 5° N (region 1), 50° S – 5° N (region 2), 30° S – 5° N (region 3), and 30° S – 30° N (region 4), using Data from NCEP reanalysis-II. Briefly, the results showed that zonal terms of potential energy and kinetic energy were intensified, except for region 1, where zonal kinetic energy weakened. Through the analysis of the period in which higher energy production is observed, a strong communication between the available zonal potential and the zonal kinetic energy reservoirs can be identified. This communication weakened the modes linked to eddies of potential energy and kinetic energy, as well as in the other two baroclinic conversions terms. Furthermore, the results indicate that for all the regions, the system itself works to regain its stable condition.

scholarly journals Breeding Temperate Japonica Rice Varieties Adaptable to Tropical Regions: Progress and Prospects

Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2253
Author(s):  
Myrish Pacleb ◽  
O-Young Jeong ◽  
Jeom-Sig Lee ◽  
Thelma Padolina ◽  
Rustum Braceros ◽  
...  
Keyword(s):  
The Philippines ◽  
Tropical Region ◽  
Japonica Rice ◽  
Rice Varieties ◽  
Temperate Japonica ◽  
Tropical Regions ◽  
Tropical Environments ◽  
Increasing Demand ◽  
Northeast Asian ◽  
The Tropics

Temperate japonica rice is mainly cultivated in temperate regions. Many temperate japonica varieties have a superior grain quality that is preferred in Northeast Asian countries such as Japan, Korea, and China. The changes in consumers’ preferences in Southeast Asia and Western countries has contributed to increasing the demand for temperate japonica. Most temperate japonica varieties developed in temperate regions typically exhibit extra-early flowering under the short-day conditions in the tropics, which usually results in severely reduced yields. Since 1992, we have been developing temperate japonica varieties that can adapt to tropical environments to meet the increasing demand for temperate japonica rice, having released six varieties in the Philippines. Especially, the yield of one of the temperate japonica varieties, Japonica 7, was comparable to the yields of leading indica varieties in the Philippines. Here, we discuss the current breeding initiatives and future plans for the development of tropical-region-bred temperate japonica rice.

Estimating kinetic energy for therapy sessions

2018 ◽  
pp. 44
Author(s):  
Alejandro Romero ◽  
Raymundo Cornejo ◽  
Fernando Martínez ◽  
Claudia Barraza ◽  
Vania Álvarez
Keyword(s):  
Kinetic Energy ◽  
Human Body ◽  
Input Device ◽  
Global Evaluation ◽  
Motion Sensing ◽  
Data Set ◽  
Daily Observation ◽  
Preliminary Results ◽  
Daily Data ◽  
Therapy Sessions

Therapists usually base the progress of the patients on a daily observation with a global evaluation every six months. This scenario could create a lack of exact and measurable daily data. Measurable data could be very helpful for monitoring patient’s progress and take important decisions regarding the therapy activities. A way to calculate the movement of a human body is through its kinetic energy. The kinetic energy measures the amount of energy spent in a therapy session or activity. The present study calculates the kinetic energy spent by children during movement based learning therapy through a data set captured with a motion sensing input device. Our preliminary results indicate an important impact on kinetic energy during this type of therapy

The equatorial wind structure in Jupiter’s stratosphere from direct wind and temperature measurements with ALMA and IRTF/TEXES

2021 ◽  
Author(s):  
Bilal Benmahi ◽  
Thibault Cavalié ◽  
Thomas K. Greathouse ◽  
Vincent Hue ◽  
Rohini Giles ◽  
...  
Keyword(s):  
Tropical Region ◽  
Temperature Structure ◽  
Horizontal Structure ◽  
Tropical Regions ◽  
Upper Troposphere ◽  
Thermal Wind ◽  
Wind Speeds ◽  
Wind Structure ◽  
First Time ◽  
Middle Stratosphere

&lt;p&gt;Since 30 years, an equatorial oscillation of the temperature structure with a quasi-period of 4 years has been discovered in the atmosphere of Jupiter (Orton et al. 1991, Leovy et al. 1991). This phenomenon results in a complex vertical and horizontal structure of prograde and retrograde jets. However, the wind structure of the stratosphere in the equatorial zone of Jupiter has not been measured directly. It has only been inferred in the tropical region from the thermal wind balance using temperatures measured in the jovian stratosphere and the cloud-top wind speeds measured as a initial condition (e.g. Flasar et al. 2004). But temperatures are not constrained between the upper troposphere and the middle stratosphere from observations, limiting thus the accuracy of the thermal wind balance.&lt;/p&gt; &lt;p&gt;In this study, we derive self-consistently for the first time the structure of the tropical winds by utilizing wind and temperature observations all performed in the stratosphere. The wind speeds were obtained by Cavali&amp;#233; et al. (2021) at 1 mbar in Jupiter's stratosphere in both the equatorial and tropical regions in March 2017 with ALMA. The stratospheric thermal field was measured a few days before from the equator to the mid-latitudes with Gemini/TEXES (Giles et al. 2020). For the derivation of the wind, we use both the thermal wind equation (Pedlosky 1979) and the equatorial thermal wind equation (Marcus et al. 2019). In this paper, we will present and discuss our results.&lt;/p&gt;

scholarly journals Partitioning Waves and Eddies in Stably Stratified Turbulence

Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 420 ◽  
Author(s):  
Henri Lam ◽  
Alexandre Delache ◽  
Fabien S Godeferd
Keyword(s):  
Dispersion Relation ◽  
Kinetic Energy ◽  
Laminar Flow ◽  
Turbulent Flow ◽  
Numerical Simulations ◽  
Direct Numerical Simulations ◽  
Energy Concentration ◽  
Kinetic Energy Density ◽  
Stratified Turbulence ◽  
The Waves

We consider the separation of motion related to internal gravity waves and eddy dynamics in stably stratified flows obtained by direct numerical simulations. The waves’ dispersion relation links their angle of propagation to the vertical θ , to their frequency ω , so that two methods are used for characterizing wave-related motion: (a) the concentration of kinetic energy density in the ( θ , ω ) map along the dispersion relation curve; and (b) a direct computation of two-point two-time velocity correlations via a four-dimensional Fourier transform, permitting to extract wave-related space-time coherence. The second method is more computationally demanding than the first. In canonical flows with linear kinematics produced by space-localized harmonic forcing, we observe the pattern of the waves in physical space and the corresponding concentration curve of energy in the ( θ , ω ) plane. We show from a simple laminar flow that the curve characterizing the presence of waves is distorted differently in the presence of a background convective mean velocity, either uniform or varying in space, and also when the forcing source is moving. By generalizing the observation from laminar flow to turbulent flow, this permits categorizing the energy concentration pattern of the waves in complex flows, thus enabling the identification of wave-related motion in a general turbulent flow with stable stratification. The advanced method (b) is finally used to compute the wave-eddy partition in the velocity–buoyancy fields of direct numerical simulations of stably stratified turbulence. In particular, we use this splitting in statistics as varied as horizontal and vertical kinetic energy, as well as two-point velocity and buoyancy spectra.

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