Vol. 35, No. 2

1.  Bhattacharya, S. K., S. D. Kotal, S. Nath, S. K. Roy Bhowmik and P. K. Kundu: Tropical cyclone intensity prediction over the North Indian Ocean - An NWP based objective approach.

A Numerical Weather Prediction (NWP) based objective intensity prediction approach has been explored for prediction of tropical cyclone intensity over the North Indian Ocean (NIO) using ECMWF model outputs. The intensity of a tropical cyclone is classified by the maximum sustained wind (10-min mean) according to World Meteorological Organization (WMO). An empirical relationship between the difference of the model's maximum mean sea level pressure (MSLP) inside a 6° × 6° grid box around the centre of the system and the lowest mean sea level pressure at the centre of the system (ΔP) with the observed intensity is developed using over 100 analyses during 2010-2012. The same is used to predict intensity of very severe cyclonic storm Hudhud and a Deep Depression observed over the Bay of Bengal during 2014. The results show that the empirical equation is skillful in prediction of intensity as compared to predictions computed using the relationship Vmax = K√ΔP with different constant values of K. The error analyses show that the relative error in intensity prediction using the empirical equation derived in the present study is 34% less than the same using K = 14.2 kt/√hPa in Vmax = K√ΔP with an improvement which is significant at the level of 0.95.

Keywords: Numerical Weather Prediction (NWP), North Indian Ocean (NIO), intensity, mean sea level pressure, pressure defect, average absolute error, standard deviation

[ PDF]

2.  Molinari, I., I. Dasović, J. Stipčević, V. Šipka, E. Kissling, J. Clinton, S. Salimbeni, S. Prevolnik, D. Giardini, S. Wiemer, the AlpArray-CASE Field Team and the AlpArray-CASE Working Group: Investigation of the Central Adriatic lithosphere structure with the AlpArray-CASE seismic experiment.

The tectonics of the Adriatic microplate is not well constrained and remains controversial, especially at its contact with the Dinarides, where it acts as the lower plate. While the northern part of the Adriatic microplate will be accurately imaged within the AlpArray project, its central and southern parts deserve detailed studies to obtain a complete picture of its structure and evolution. We set-up the Central Adriatic Seismic Experiment (CASE) as a AlpArray Complementary Experiment with a temporary seismic network to provide high-quality seismological data as a foundation for research with state-of-the-art methods and high-precision seismic images of the controversial area. The international AlpArray-CASE project involves four institutions: the Department of Earth Sciences and the Swiss Seismological Service of ETH Zürich (CH), the Department of Geophysics of the Faculty of Science at the University of Zagreb (HR), the Republic Hydrometeorological Service of the Republic of Srpska (BIH) and Istituto Nazionale di Geofisica e Vulcanologia (I). The established temporary seismic network will be operational for at least 18 months. It combines existing permanent and temporary seismic stations operated by the involved institutions together with newly deployed temporary seismic stations, installed in November and December 2016, managed by ETH Zürich and INGV: five in Croatia, four in Bosnia and Herzegovina and one in Italy. We present our scientific aims and network geometry as well as newly deployed stations sites and settings. In particular, the new stations show favourable noise level (power spectral density estimates). The new network improves considerably the theoretical ray coverage for ambient noise tomography and the magnitude threshold shown in the Bayesian magnitude of completeness threshold map.

Keywords: AlpArray, Adriatic microplate, Dinarides, lithosphere, seismic networks, noise level

[ PDF]