Dr.C A Babu
https://dyuthi.cusat.ac.in:443/xmlui/handle/purl/3776
2024-02-07T16:46:10ZMeteorological aspects of mud bank formation along south west coast of India
https://dyuthi.cusat.ac.in:443/xmlui/handle/purl/3805
Meteorological aspects of mud bank formation along south west coast of India
Babu,C A; Asha, Philip S; Hareeshkumar, P V
The study mainly intends to investigate the meteorological aspects associated with the formation of mud
banks along southwest coast of India. During the formation of mud bank, the prominent monsoon
organized convection is located in the equatorial region and relatively low clouding over Indian
mainland. The wind core of the low level jet stream passes through the monsoon organized convection.
When the monsoon organized convection is in the equatorial region, the low level wind over the
southwest coast of India is parallel to the coastline and toward south. This wind along the coast gives rise
to Ekman mass transport away from the coastline and subsequently formation of mud bank, if the high
wind stress persists continuously for three or more days. As a result of the increased alongshore wind
stress, the coastal upwelling increases. An increase in chlorophyll-a concentration and total chlorophyll
can also be seen associated with mudbank formation
www.elsevier.com/locate/csr
2013-08-15T00:00:00ZRole of sea-surface wind and transport on enhanced aerosol optical depth observed over the Arabian Sea
https://dyuthi.cusat.ac.in:443/xmlui/handle/purl/3804
Role of sea-surface wind and transport on enhanced aerosol optical depth observed over the Arabian Sea
Babu,C A; Shivaprasad, P
The objective of this study is to understand the reasons for the enhancement in
aerosol optical depth (AOD) over the Arabian Sea observed during June, July and
August. During these months, high values of AOD are found over the sea beyond
10◦ N and adjacent regions. The Arabian Sea is bounded by the lands of Asia
and Africa on its three sides. So the region is influenced by transported aerosols
from the surroundings as well as aerosols of local origin (marine aerosols). During
the summer monsoon season in India, strong surface winds with velocities around
15 m s−1 are experienced over most parts of the Arabian Sea. These winds are capable
of increasing sea spray activity, thereby enhancing the production of marine
aerosols. The strong winds increase the contribution of marine aerosols over the
region to about 60% of the total aerosol content. The main components of marine
aerosols include sea salt and sulphate particles. The remaining part of the aerosol
particles comes from the western and northern land masses around the sea, of
which the main component is transported dust particles. This transport is observed
at higher altitudes starting from 600 m. At low levels, the transport occurs mainly
from the Indian Ocean and the Arabian Sea itself, indicating the predominance
of marine aerosols at these levels. The major portion of the total aerosol loading
was contributed by coarse-mode particles during the period of study. But in the
winter season, the concentration of coarse-mode aerosols is found to be less. From
the analysis, it is concluded that the increase in marine aerosols and dust particles
transported from nearby deserts results in an increase in aerosol content over the
Arabian Sea during June, July and August.
International Journal of Remote Sensing
Vol. 33, No. 16, 20 August 2012, 5105–5118
2012-02-17T00:00:00ZLong term trends of seasonal and monthly rainfall in different intensity ranges over Indian subcontinent
https://dyuthi.cusat.ac.in:443/xmlui/handle/purl/3801
Long term trends of seasonal and monthly rainfall in different intensity ranges over Indian subcontinent
Babu,C A; Hamza, Varikoden; Krishnakumar, K
In general Indian summer monsoon rainfall did not show any significant trend in all Indian summer monsoon rainfall series, however, it was reported that the ISMR is subjected to spatial trends. This paper made an attempt to bring out long term trends of different intensity classes of summer monsoon rainfall in different regions of Indian subcontinent. The long term trend of seasonal and monthly rainfall were also made using the India Meteorological Department gridded daily rainfall data with a spatial resolution of 1° × 1° latitude-longitude grid for the period from 1st January, 1901 to 31st December, 2003. The summer monsoon rainfall shows an increasing trend in southeast, northwest and northeast regions, whereas decreasing trend in the central and west coastal regions. In monthly scale, July rainfall shows decreasing trend over west coastal and central Indian regions and significant increasing trend over northeast region at 0.1% significant level. During the month August, decreasing trend is observed in the west coastal stations at 10% significant level. In most of the stations, mean daily rainfall shows an increasing trend for low and very high intense rainfall. For the moderate rainfall, the trend is different for different regions. In the central and southern regions the trend of moderate and moderately high classes show increasing trend. And for the high and very high intensity classes, the trend is decreasing significantly. In the northeastern regions, above 10 mm/day rainfall shows significantly increasing trend with 0.1% significant level.
MAUSAM, 64, 3 (July 2013), 481-488
2012-10-16T00:00:00ZDiurnal Structure of Monsoon Boundary Layer
https://dyuthi.cusat.ac.in:443/xmlui/handle/purl/3800
Diurnal Structure of Monsoon Boundary Layer
Babu,C A; Hamza, V
The characteristics of the monsoon boundary layer are imperative to understand in the perception of the tropical
regions. The southwest monsoon is associated with a strong wind in the lower troposphere near 1.5 km and is referred to
as Low Level Jet stream (LLJ). The boundary layer structure associated with the LLJ during monsoon can be studied
using L-band Ultra High Frequency (UHF) radar. This L-band wind profiler-commonly referred as lower atmospheric
wind profiler (LAWP), was installed at NARL, Gadanki. Zonal, meridional and vertical wind components are used to
understand the diurnal variation of the wind in the Atmospheric Boundary Layer (ABL) and associated features. From the
analysis during non rainy days of the southwest monsoon, it is found that the LLJ has maximum strength during the early
morning hours at lower level and the height increases as day progresses. The vertical wind shows the transfer of momentum
from the LLJ towards the surface, indicating the sinking motion during the daytime. Vertical gradient of the wind shear
shows the intensity of clear air turbulence is moderate and no severe clear air turbulence is noticed during the monsoon
period
J.Mar. Atmos. Res. Vol.3, No.2 July 2007, 51-59
2007-07-01T00:00:00Z