Investigation on the consequential features of Southwest Monsoon-2007 Onset and Super cyclone "Gonu" using Satellite, Model and Ground-based data

Onset features of the Summer monsoon-2007 were analyzed using data from five different sources, namely,the Tropical Rainfall Measuring Mission (TRMM) 3-hourly rainfall, National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) wind reanalysis data set, NOAA Outgoing Longwave Radiation (OLR), cloud imageries from the meteosat satellite,cloud base height and cloud occurrence frequency from a ground-based Vaisala Laser Ceilometer at Thiruvananthapuram. On the day of onset, 33 mm of rainfall was registered by TRMM satellite over south Kerala region with 80% cloud frequency and an averaged cloud base height of 2 km. On the next day, the formation of ‘Gonu’ super cyclone as a consequence of the convergence of monsoon onset surge in the Arabian Sea has caused the dissipation of cloud bands in the Arabian Sea and in the Bay of Bengal, except over the region of the system. This caused a lull situation for about ten days after the India Meteorological Department (IMD) declared monsoon onset. In fact, the remarkable characteristics of onset, such as deepening of westerlies and strengthening of low level jet streams were observed only after two weeks of IMD declared monsoon onset. Another unique behavior of 2007 monsoon onset was that the Arabian Sea branch of monsoon onset surge has advanced faster than the Bay of Bengal branch in the early stage

Quantisation of Klein–Gordon field in

In this paper we study the quantisation of scalar field theory in $$\kappa$$-deformed space-time. Using a quantisation scheme that use only field equations, we derive the quantisation rules for deformed scalar theory, starting from the $$\kappa$$-deformed equations of motion. This scheme allows two choices; (1) a deformed commutation relation between the field and its conjugate which leads to usual oscillator algebra, (2) an undeformed commutation relation between field and its conjugate leading to a deformed oscillator algebra. This deformed oscillator algebra is used to derive modification to Unruh effect in the $$\kappa$$-space-time

Observational study of cloud base height and its frequency over a tropical station, Thiruvananthapuram, using a ceilometer

This study aims to investigate the characteristic features of cloud base height (CBH) over Thiruvananthapuram during different seasons. CBH data were used for the present work derived from the Vaisala Laser Ceilometer, CL31 (VLC) installed at the campus of the Centre for Earth Science Studies, Akkulam (8.29° N, 76.59° E, 15 m above sea level). The VLC was in operation from the second week of July 2006 onwards. From the study, we found that CBH shows distinct diurnal and seasonal variations during all the seasons (except on rainy days). The diurnal variation for low-level clouds was different from that for the mid-level clouds. A cloud-free layer is evident in the region between 2.5 and 4 km. This cloud-free zone is more prominent during the southwest monsoon period compared to other seasons. Moreover, the monthly variations of cloud frequency and CBH were also described in addition to the different periodicities in cloud frequency. The periodicities found in the cloud frequency were 8 days and 30 days and these are significant at the 5 level. Thermodynamic parameters from the radiosonde were also related to the cloud frequency for various seasons and they were in good agreement