• SRINIVAS DESAMSETTI

Articles written in Journal of Earth System Science

• Trends in the genesis and landfall locations of tropical cyclones over the Bay of Bengal in the current global warming era

Trends in tropical cyclone (TC) genesis and landfall over the Bay of Bengal (BOB) were analysed to identify global warming and climate change impacts. The historical TC data for the period 1901–2015 available through the cyclone eAtlas from India Meteorological Department were used. The analysis was confined to the 3-month period from October to December when the maximum number of TCs occurs over the BOB. Analysis was conducted for the two 50-yr periods of 1901–1950 and 1961–2010 and the four 30-yr periods of 1921–1950, 1961–1990, 1971–2000 and 1981–2010 to ascertain the differences and tendencies in the genesis and landfall points during the current global warming era since the 1960s and the previous years. The results indicate an increase of TC genesis over the south-east and central BOB and decrease over the south central region. Furthermore, an increased vulnerability of the Bangladesh coastline to TC landfall was detected. In addition, TC systems had decreased in number but increased in intensity. These results confirm the general reports of TC trends over the BOB as of other ocean basins in the post-industrialisation global warming era.

• Sensitivity to initial conditions on the simulation of extratropical cyclone ‘Gong’ formed over North Atlantic

The role of initial conditions (ICs) in the simulation of severe winter storm ‘Gong’ formed over North Atlantic is studied. The life cycle of Gong started at 1800 UTC of 16–0600 UTC of 22 January, 2013, with CSLP of 972 hPa. The gusty wind (${\sim}$33 ms$^{-1}$) and torrential rainfall of ${\sim}$90 mm d$^{-1}$ recorded over several major cities of the Iberian peninsula. Five numerical experiments were performed with the WRF model by initializing at 0600 UTC of 16, 1800 UTC of 16, 0600 UTC of 17, 1800 UTC of 17, and 0600 UTC of 18 January, 2013. Our results suggest that significant differences are seen among the experiments, particularly with the ICs of 0600 UTC 17 January, 2013, which represent the quick movement of Gong with a slight underestimation of intensity. The experiment with IC 0600 UTC on 18 January, 2013 produced the best simulation as compared to the observations. The simulated track, intensity, wind flow, and rainfall were well agreeing with the observations. The 12-h average track errors were ranging from 95 to 332 km with 24-, 36-, 48-, 60-, and 72-h lead time. The Q-vectors of Gong with the WRF model with 24-h lead time produced minimum errors.

$\bf{Highlights}$

$\bullet$ Sensitivity of initial and boundary conditions (ICs) are studied for an extra-tropical cyclone (ETC, Gong (2013)) over North Atlantic Ocean using WRF model.

$\bullet$ Movement (track) and synoptic feature of Gong have been evaluated with observations. WRF could simulate the characteristics throughout life cycle of Gong.

$\bullet$ The model attained intense stage was well simulated.

$\bullet$ Cyclogenesis and Q-Vector for Gong are sensitive to the ICs and model could simulate better with 48-h lead time.

• Assessment of wind energy potential over India using high-resolution global reanalysis data

An assessment of wind energy potential based on wind speed data over the Indian subcontinent has been made using high spatio-temporal resolution global reanalysis for the period from 1979 to 2018. Regions of high wind speed exceeding 4.5 m/s are identified over West Rajasthan, West Gujarat, Saurashtra and Kutch, Central Maharashtra, Interior Karnataka, and Rayalaseema. Threshold wind speeds are noted to occur during the daytime, and during the summer months from May through September. Wind speeds and the spatial extent of threshold winds increase rapidly with height below 40 m and then gradually up to 100 m. The wind power density is highest between 50 and 80 m, with the potential highest over Gujarat, Kutch, and Interior Karnataka and moderate over Saurashtra and Rayalaseema. This study also notifies that offshore wind potential is higher than over land, and most of the western parts of India are congenial for low wind farming. The present study clearly delineates wind speed distributions and wind power productivity regions over the entire Indian subcontinent. The results would provide authentic wind speed and wind power potential information that would be useful for the industries, government agencies, and industries concerning wind harness over India.

$\bf{Highlights}$

$\bullet$ Wind power potential is assessed over the Indian subcontinent.

$\bullet$ Spatial regions of wind speeds at different thresholds were identified.

$\bullet$ Durations of wind speed hours per day for different thresholds were estimated.

$\bullet$ Wind power potential at different heights was evaluated.

$\bullet$ Favourable regions for wind farming over the Indian subcontinent were presented.

• # Journal of Earth System Science

Volume 130, 2021
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019