The coupled influence of instability indices and DWR data in estimating the squall speed of thunderstorms

2013 ◽  
Vol 49 (4) ◽  
pp. 451-465 ◽  
Author(s):  
Sutapa Chaudhuri ◽  
Sayantika Goswami ◽  
Anirban Middey
Keyword(s):  
Dwr Data ◽  
Instability Indices

scholarly journals Growth, instability and forecast of marine products export from India

2016 ◽  
Vol 63 (4) ◽  
Author(s):  
Apu Das ◽  
Nalini Ranjan Kumar ◽  
Prathvi Rani
Keyword(s):  
Moving Average ◽  
Export Performance ◽  
Arima Model ◽  
South East Asia ◽  
Arima Models ◽  
Policy Makers ◽  
Increasing Trend ◽  
Marine Products ◽  
Auto Regressive ◽  
Instability Indices

This paper analysed growth and instability in export of marine products from India with an attempt to forecast the total export quantity of marine products from the country. The compound growth rates and instability indices of marine products export from India were estimated for major importing countries viz., Japan, USA, European Union, South-east Asia and Middle East; as more than 80% of the marine products export from India destines to these markets. The study revealed high compound growth rate and low instability in case of selected countries. The study also revealed that India’s marine products export concentrated mainly to those countries, which were falling in less desirable or least desirable category which has affected export performance of the country. Forecast of India’s marine products export was done by fitting univariate Auto Regressive Integrated Moving Average (ARIMA) models. ARIMA (1, 1, 0) was found suitable for modelling marine products export from India. The results of ARIMA model indicated increasing trend in export of Indian marine products. This calls for serious attention by policy makers to identify competitive and stable market destinations for marine products export which could help in harnessing the potential of marine products export from India.

scholarly journals Interrelation among different instability indices of the troposphere over Dhaka associated with thunderstorms/nor'westers over Bangladesh during the pre-monsoon season

MAUSAM ◽  
2021 ◽  
Vol 58 (3) ◽  
pp. 361-368
Author(s):  
SAMARENDRA KARMAKAR ◽  
MD. MAHBUB ALAM
Keyword(s):  
Monsoon Season ◽  
Stability Index ◽  
Dew Point ◽  
Standard Errors ◽  
Regression Equations ◽  
K Index ◽  
Total Index ◽  
Level Of Significance ◽  
Almost All ◽  
Instability Indices

Attempts have been made to correlate different instability indices among themselves statistically. The study reveals that the Showalter Stability Index (SI) has moderate to good correlations with different instability indices except Dew-point Index (DPI), Vertical Total Index (VT), Modified Vertical Total Index (MVT) and Modified K-Index (MK). Most of the correlations co-efficient are found to be significant up to 99% level of significance except Dry Instability Index (DII), which has correlation with SI up to 95% level of significance. Lifted Index (LI) has moderate to good correlation with different instability indices except DII, K-Index (KI) and MVT. Most of the correlations co-efficient are significant up to 99% level of significance except VT, SWEAT Index (SWI) and MKI, which have correlation with LI up to 95% level of significance. Unmodified instability indices have moderate to strong correlation with the corresponding modified instability indices, having 99% level of significance. The correlation co-efficient of VT and MVT, SWI and Modified SWEAT Index (MSWI), and KI and MKI are comparatively large. Standard errors of estimate are small in almost all the cases except a few. The regression equations obtained are likely to be helpful in the computation of different instability indices.

Association of atmospheric pollution and instability indices: A detailed investigation over an Indian urban metropolis

2017 ◽  
Vol 196 ◽  
pp. 83-96 ◽  
Author(s):  
Rohit Chakraborty ◽  
Upal Saha ◽  
A.K. Singh ◽  
Animesh Maitra
Keyword(s):  
Atmospheric Pollution ◽  
Instability Indices

Selected instability indices in Europe

2008 ◽  
Vol 96 (1-2) ◽  
pp. 85-94 ◽  
Author(s):  
Mariusz Siedlecki
Keyword(s):  
Instability Indices

scholarly journals Impact of extreme cyclone events on coastal agriculture in Bangladesh

2019 ◽  
Vol 30 ◽  
pp. 33-41
Author(s):  
MA Farukh ◽  
MAM Hossen ◽  
S Ahmed
Keyword(s):  
Climate Change ◽  
Storm Surge ◽  
Crop Production ◽  
Gis Technology ◽  
Cyclonic Storm ◽  
Recent Climate ◽  
The World ◽  
Approximate Percentage ◽  
Boro Rice ◽  
Instability Indices

Extreme cyclone events are now occurring more frequently in Bangladesh. Bangladesh experiences severe 52 cyclones from 1960 to 2010 where, the approximate percentage of storm surge impact is 40%, the largest in the world. A severe cyclone in 1970 and 1991 caused loss of 300,000 and 200,000 lives. It is reported that 210000, 36000, and 3500 tonnes of boro rice, aus rice, and other food crops (e.g. potatoes and vegetables) were totally destroyed by 1991 cyclone. The storm surge killed huge livestock and caused loss of 100% of freshwater fish. Recently, the super cyclonic storm SIDR (2007) and AILA (2009) affected 10,000 and 300,000 people, respectively. Apart from these, cyclones NARGIS (2008) and MOHASEN (2013) are also mentionable. The crop production in the coastal regions of Bangladesh is most vulnerable by cyclones while, sea level rise by 2050 will inundate 17.7% of southern coastal areas. Tropical cyclones could become more frequent with more strength under recent climate change conditions. In this research, a new dimension of extreme weather assessment is done combining GCM and GIS technology and using tropospheric instability indices. The thermodynamic environment, vertical instability characteristics of severe cyclones are indispensable to cope with climate change conditions, and for planning, disaster management, and to reduce the risk of food insufficiency. Progressive Agriculture, Vol. 30, Suppl. 1: 33-41, 2019

scholarly journals Instability indices and forecasting thunderstorms: the case of 30 April 2009

2012 ◽  
Vol 12 (2) ◽  
pp. 403-413 ◽  
Author(s):  
S. Tajbakhsh ◽  
P. Ghafarian ◽  
F. Sahraian
Keyword(s):  
Relative Humidity ◽  
Prediction Model ◽  
Numerical Weather Prediction ◽  
Vertical Velocity ◽  
Weather Prediction ◽  
Numerical Weather Prediction Model ◽  
Weather Station ◽  
Using Data ◽  
Instability Indices

Abstract. In this paper, one meteorological case study for two Iranian airports are presented. Attempts have been made to study the predefined threshold amounts of some instability indices such as vertical velocity and relative humidity. Two important output variables from a numerical weather prediction model have been used to survey thunderstorms. The climatological state of thunder days in Iran has been determined to aid in choosing the airports for the case studies. The synoptic pattern, atmospheric thermodynamics and output from a numerical weather prediction model have been studied to evaluate the occurrence of storms and to verify the threshold instability indices that are based on Gordon and Albert (2000) and Miller (1972). Using data from the Statistics and Data Center of the Iran Meteorological Organization, 195 synoptic stations were used to study the climatological pattern of thunderstorm days in Iran during a 15-yr period (1991–2005). Synoptic weather maps and thermodynamic diagrams have been drawn using data from synoptic stations and radiosonde data. A 15-km resolution version of the WRF numerical model has been implemented for the Middle East region with the assistance of global data from University Corporation for Atmospheric Research (UCAR). The Tabriz airport weather station has been selected for further study due to its high frequency of thunderstorms (more than 35 thunderstorm days per year) and the existence of an upper air station. Despite the fact that storms occur less often at the Tehran weather station, the station has been chosen as the second case study site due to its large amount of air traffic. Using these two case studies (Tehran at 00:00 UTC, 31 April 2009 and Tabriz at 12:00 UTC, 31 April 2009), the results of this research show that the threshold amounts of 30 °C for KI, −2 °C for LI and −3 °C for SI suggests the occurrence and non-occurrence of thunderstorms at the Tehran and Tabriz stations, respectively. The WRF model output of vertical velocity and relative humidity are the two most important indices for examining storm occurrence, and they have a numerical threshold of 1 m s−1 and 80%, respectively. These results are comparable to other studies that have examined thunderstorm occurrence.

Sign in / Sign up

Export Citation Format

Share Document