scholarly journals Cyclones and depressions over north Indian Ocean during 2001

MAUSAM ◽  
2022 ◽  
Vol 53 (3) ◽  
pp. 265-270
Author(s):  
Editor Mausam
Keyword(s):  
Indian Ocean ◽  
North Indian Ocean

scholarly journals Design of Wave Glider Optimal Parameters Suitable for the Northwest Pacific Ocean, the North Indian Ocean, and the South China Sea

2021 ◽  
Vol 9 (4) ◽  
pp. 408
Author(s):  
Xi Chen ◽  
Mei Hong ◽  
Shiqi Wu ◽  
Kefeng Liu ◽  
Kefeng Mao
Keyword(s):  
Indian Ocean ◽  
South China Sea ◽  
South China ◽  
North Indian Ocean ◽  
Northwest Pacific ◽  
Northwest Pacific Ocean ◽  
The North ◽  
Wave Element ◽  
Wave Glider ◽  
The Northwest Pacific Ocean

To study the optimal design of Wave Glider parameters in the wave environment of the Northwest Pacific Ocean, the North Indian Ocean, and the South China Sea, the average velocity of a Wave Glider was taken as the evaluation criterion. Wave reanalysis data from ERA5 were used to classify the mean wave height and period into five types by the K-means clustering method. In addition, a dynamic model was used to simulate the influence of umbilical length, airfoil, and maximum limited angle on the velocity of the Wave Glider under the five types of wave element. The force of the wings was simulated using FLUENT as the model input. The simulation results show that (1) 7 m is the most suitable umbilical length; (2) a smaller relative thickness should be selected in perfect conditions; and (3) for the first type of wave element, 15° is the best choice for the maximum limited angle, and 20° is preferred for the second, third, and fourth types, while 25° is preferred for the fifth type.

Extended Prediction of North Indian Ocean Tropical Cyclones

2012 ◽  
Vol 27 (3) ◽  
pp. 757-769 ◽  
Author(s):  
James I. Belanger ◽  
Peter J. Webster ◽  
Judith A. Curry ◽  
Mark T. Jelinek
Keyword(s):  
Tropical Cyclone ◽  
Indian Ocean ◽  
Tropical Cyclones ◽  
North Indian Ocean ◽  
Ensemble Prediction ◽  
Tropical Cyclone Genesis ◽  
Lead Times ◽  
Prediction System ◽  
Ensemble Prediction System ◽  
The North

Abstract This analysis examines the predictability of several key forecasting parameters using the ECMWF Variable Ensemble Prediction System (VarEPS) for tropical cyclones (TCs) in the North Indian Ocean (NIO) including tropical cyclone genesis, pregenesis and postgenesis track and intensity projections, and regional outlooks of tropical cyclone activity for the Arabian Sea and the Bay of Bengal. Based on the evaluation period from 2007 to 2010, the VarEPS TC genesis forecasts demonstrate low false-alarm rates and moderate to high probabilities of detection for lead times of 1–7 days. In addition, VarEPS pregenesis track forecasts on average perform better than VarEPS postgenesis forecasts through 120 h and feature a total track error growth of 41 n mi day−1. VarEPS provides superior postgenesis track forecasts for lead times greater than 12 h compared to other models, including the Met Office global model (UKMET), the Navy Operational Global Atmospheric Prediction System (NOGAPS), and the Global Forecasting System (GFS), and slightly lower track errors than the Joint Typhoon Warning Center. This paper concludes with a discussion of how VarEPS can provide much of this extended predictability within a probabilistic framework for the region.

scholarly journals Effect of tropical cyclones on the Stratosphere-Troposphere Exchange observed using satellite observations over north Indian Ocean

2016 ◽  
Author(s):  
M. Venkat Ratnam ◽  
S. Ravindra Babu ◽  
S. S. Das ◽  
Ghouse Basha ◽  
B. V. Krishnamurthy ◽  
...  
Keyword(s):  
Water Vapor ◽  
Indian Ocean ◽  
Tropical Cyclones ◽  
Lower Stratosphere ◽  
North Indian Ocean ◽  
Satellite Observations ◽  
Upper Troposphere ◽  
North West ◽  
The North ◽  
The Impact

Abstract. Tropical cyclones play an important role in modifying the tropopause structure and dynamics as well as stratosphere-troposphere exchange (STE) process in the Upper Troposphere and Lower Stratosphere (UTLS) region. In the present study, the impact of cyclones that occurred over the North Indian Ocean during 2007–2013 on the STE process is quantified using satellite observations. Tropopause characteristics during cyclones are obtained from the Global Positioning System (GPS) Radio Occultation (RO) measurements and ozone and water vapor concentrations in UTLS region are obtained from Aura-Microwave Limb Sounder (MLS) satellite observations. The effect of cyclones on the tropopause parameters is observed to be more prominent within 500 km from the centre of cyclone. In our earlier study we have observed decrease (increase) in the tropopause altitude (temperature) up to 0.6 km (3 K) and the convective outflow level increased up to 2 km. This change leads to a total increase in the tropical tropopause layer (TTL) thickness of 3 km within the 500 km from the centre of cyclone. Interestingly, an enhancement in the ozone mixing ratio in the upper troposphere is clearly noticed within 500 km from cyclone centre whereas the enhancement in the water vapor in the lower stratosphere is more significant on south-east side extending from 500–1000 km away from the cyclone centre. We estimated the cross-tropopause mass flux for different intensities of cyclones and found that the mean flux from stratosphere to troposphere for cyclonic stroms is 0.05 ± 0.29 × 10−3 kg m−2 and for very severe cyclonic stroms it is 0.5 ± 1.07 × 10−3 kg m−2. More downward flux is noticed in the north-west and south-west side of the cyclone centre. These results indicate that the cyclones have significant impact in effecting the tropopause structure, ozone and water vapour budget and consequentially the STE in the UTLS region.

scholarly journals Trend of shift in the area of cyclo-genesis over north Indian Ocean

MAUSAM ◽  
2021 ◽  
Vol 58 (1) ◽  
pp. 49-58
Author(s):  
CHARAN SINGH ◽  
B. R. LOE
Keyword(s):  
Standard Deviation ◽  
Indian Ocean ◽  
Bay Of Bengal ◽  
Arabian Sea ◽  
North Indian Ocean

ABSTRACT. Cyclo-genesis over north Indian Ocean (Bay of Bengal and the Arabian Sea) has been studied with reference to the formation and shift of cyclo-genesis area. The frequency of formation of cyclones during a particular month and year for the period of study has been presented. The study has shown that the maximum number of cyclo-genesis occurred during the month of July followed by August and September. Cyclo-genesis was about three times more in the Bay of Bengal as compared to that in the Arabian Sea. Areas favourable for cyclo-genesis were found between Lat. 15.0° N to 22.5° N and Long. 86.0° E to 92.0° E over the Bay of Bengal and Lat. 7.0° N to 12.5° N and 60.0° E to 74.0° E over the Arabian sea while meander over north Indian ocean, some times its shift significantly. Standard deviation of number of cyclones has been computed for the decades from 1891-2000. It was found that it was maximum (1.96) during 1941-1950 followed by 1981-1990 (1.92).

Sign in / Sign up

Export Citation Format

Share Document