Influence of cyclone Phailin on the Upper Ocean over Bay of Bengal · 2017-08-14 · Influence of...

International Journal of Applied Environmental Sciences

ISSN 0973-6077 Volume 12, Number 5 (2017), pp. 717-729

© Research India Publications

http://www.ripublication.com

Influence of cyclone Phailin on the Upper Ocean over

Bay of Bengal

C. Purna Chand1, M.V. Rao1, K.V.S.R. Prasad2 and K.H. Rao1

1National Remote Sensing Centre, Hyderabad, India 2 Dept. of Meteorology and Oceanography, Andhra University, Visakhapatnam, India

Abstract

The influence of cyclonic storm Phailin during October 2013 on the ocean

surface over Bay of Bengal have been studied using Earth Observation (EO)

Sensors data as well as in-situ observations including temperature and salinity

profiles from Argo float data near vicinity of the Phailin track. The Phailin

(8th to 13th October 2013) induced cooling along the cyclone track is clearly

seen with substantial cooling observed before the landfall of the cyclone. This

cooling is a result of vertical mixing induced by upwelling due to strong winds

and Ekman current during the Phailin Cyclone. The significant wave height

increase along the coast is observed in the SARAL-Altika and Jason-2

Altimeter data. The pressure drop and the increase in salinity are found during

12th October 2013 due to passage of Phailin cyclone.

Keywords: Cyclone, Argo float, phailin, upper ocean, vertical mixing.

1. INTRODUCTION

Meteorologists use the term "tropical cyclone" for a closed atmospheric circulation

that forms over a tropical or subtropical ocean. Once maximum sustained wind speed

exceeds 74 miles per hour these storms are called hurricanes in the Atlantic Ocean,

typhoons in the Pacific Ocean, and very severe cyclones (super cyclones in recent

terminology) in the Indian Ocean.

The Tropical Cyclone damages the property and lot of casualties in coastal regions

due to gale winds and heavy rains associated flooding. People realized that the oceans

play a significant role in formation, development and strengthening of Tropical

718 C. Purna Chand, M.V. Rao, K.V.S.R. Prasad and K.H. Rao

Cyclone. Aftermath of Tropical Cyclone, variation in Sea Surface Temperature, gale

winds, Sea Waves, Surface Pressure, currents and biological activity are seen. The

changes of these parameters due to Tropical Cyclone are studied independently by

several researchers. The Cyclone induced Sea Surface Temperature cooling has been

investigated by different authors, using remotely sensed data sets [Stramma et al.,

1986, Peter et al., 1995, Suetsugu et al., 2000, Rao et al., 2002, Sadhuram. Y., 2004,

and Yablonsky et al., 2013]. Space-born wind measurements and significant response

to the strong wind forcing during tropical cyclone have been noticed [Atlas et al.,

1996, Atlas and Hoffman 2000, Adams et al., 2005, 2006, Liu and Xie 2008, Shuwen

Zhang et al., 2014, C P Chand et al., 2014, 2015 and Sasamal et al., 2015]. The impact

of Scatterometer wind on tropical cyclone forecasting has been studied [Isaksen and

Stoffelen 2000]. The nutrients are efficiently replenished in euphotic layer and

phytoplankton biomass rapidly enhanced due to tropical storm passage [Shiah et al.,

2000, Subramanyam et al., 2002,Preethi et al, 2015 and Aneesh et al., 2014].

The upper ocean response to a moving storm has been an important and interesting

topic in the physical and biological oceanographic studies. Keeping this in view, a

comprehensive study during one Tropical Cyclone (Phailin) using Earth Observation

Sensors data and in-situ observations during October 8-14, 2013 has been carried out.

1.1 Very Severe Cyclonic Storms ‘Phailin’

The cyclone Phailin during October 8-14, 2013 is the category four Hurricane, out of

three very severe cyclonic storms occurred during 2013. As per India Meteorological

Department (IMD) [www.imd.gov.in] reports on 8th October 2013 the Deep

Depression upgraded to Cyclone and subsequently a cyclonic storm named it as

Phailin. It is further strengthened and formed into a very severe cyclonic storm by

10th October 2013. The Phailin is further intensified with a central pressure of 994

mb and crossed the coast near Gopalpur, Odisha, East Coast of India on 12th October

2013. The cyclone ‘Phailin’ prompted India's biggest evacuation in last 23 years with

more than 550,000 people moving up from the coastline in Odisha and Andhra

Pradesh to safer places. Forty four deaths and 696 million USD damage due to the

cyclone have been reported.

2. DATA USED AND METHODOLOGY

In this study Level 2B wind field data from Ocean Sat-2 Scatterometer (OSCAT)

obtained during Phailin Cyclone (both descending and ascending passes, equatorial

crossing time nearly at 6:30 and 18:30 GMT respectively) from NRSC, Hyderabd.

The wind field data (both speed and direction) is available in 25 Km and 50 Km grid

size. The 25 Km wind field data has been used to estimate wind stress and wind

Influence of cyclone Phailin on the Upper Ocean over Bay of Bengal 719

stress curl using standard formula [Sourabh et al., 2014]. The 50 Km wind field data

is used to compute pressure fields using University of Washington Planetary

Boundary Layer (UWPBL) Model as described by Patoux et al., [2003]. The UWPBL

model compute surface wind from the knowledge of geostrophic wind ‘Farward’ and

‘Inverse’ model calculate geostrophic wind at top of boundary layer from surface

wind. The boundary layer wind in two different models viz; two layer similarity

model for mid-latitude (60o to 10oS and 10o to 60oN) and Mixed layer model for

tropical region (20oS to 20oN) yield the pressure gradients. The absolute pressure

values can be obtained through least square fit from a priori pressures from

observations/model values and here we used buoy data from Indian National Centre

for Ocean Information Services (INCOIS) [www.incois.gov.in] as a priori pressures.

The model required input data other than wind fields on air temperature, sea surface

temperature, humidity, and horizontal temperature gradient. These inputs are taken

from the climatological data.

The Sea Surface Temperatures (SSTs) both daily and weekly were extracted from

Tropical Rainfall Measuring Mission’s (TRMM) Microwave Imager (TMI)

[www.remss.com] during the period of cyclone Phailin to study the cooling effect.

The ocean surface currents are estimated from Ekman surface current through

OSCAT wind stress component and geostrophic current through SARAL Altika

derived sea surface heights [Saurabh et al., 2014]. The chlorophyll-a estimates are

obtained from OCM-2 data during Phailin. The significant wave heights were

estimated using the Saral-Altika and Jason-2 data during Phailin Cyclone.

In addition temperature and salinity profile Argo float data near vicinity of the Phailin

track were obtained from coriolis project and programs (http://www.coriolis.eu.org)

during cyclone period. These profile data are used to compute Mixed Layer Depth

(MLD).

3. RESULTS AND DISCUSSIONS

The Tropical Cyclone ‘Phailin’ induced changes over Bay of Bengal were studied

with the help of multi sensor derived ocean parameters. Normally during the Tropical

Cyclone, the heat transfer from ocean to the atmosphere through evaporation is

enhanced by cyclone induced surface winds, which transport water vapor to the

troposphere.

Other way the cyclone induced surface winds do generate upper-ocean currents and

this process of current generation does not happen directly. The winds build up

waves at the sea surface, and some of the energy from the winds goes into growing

and propagating these waves. When the waves break, energy is transferred downward

into the ocean currents.


The cyclone-induced chl-a increase is another process accounting for a few percent of

the total chl-a increase in some areas. In oligotrophic regions, the increase in chl-a

tended to become larger as the corresponding SST decrease became larger, although

the relationship between them is opposite in mesotrophic and eutrophic regions.

3.1 Sea Surface Temperature

To compare the sea surface temperatures during cyclone period with that prior to

cyclone, SSTs from first week of October 2013 (i.e. week ending on 5th October

2013) have been chosen as reference. The SST anomaly’s estimated from the

individual day SST from 8th to 13th October, 2013 by subtracting daily SST from

weekly (week ending on 5th October 2013) SSTs. Hence the positive value indicates

cooling and negative represents warming. The colour coded SST anomaly images are

generated, have been presented in figure 1(a). The temperature anomalies during the

cyclone period along the track from 8th to 13th have been presented in figure 1(b). It is

seen from figure 1, that the cooling is observed 1.0 to 2.0 0 C from 8th to 11th and

cooling increases as it approaches to the coast, attains maximum (≈ 6.0 0C) on 13th

October 2013 near land fall point.

Figure 1. (a) Colour coded images depicting SST anomaly (weekly average for the

week ending on 5th October 2013 minus SSTs of daily from 8th to 13th October 2013),

high positive anomaly along coast indicate maximum cooling on 13th October 20113.

(b) SST anomaly all along the Phailin cyclone track is shown from 8th to 13th October

2013(Maximum cooling observed).


The upwelling caused by the cyclonic storm has to be balanced by the downwelling at

the adjoining place. When the storm is closer to the coast, the downwelling might

have probably taken place to the west of the storm, which is evident from the positive

SST anomalies towards the west of the cyclonic track. The storm also has generated

coastally trapped Kelvin waves with cooler waters that propagated towards the east

coast of India. The extent of these cooled waters near the east coast of India is clearly

seen during the landfall of cyclone Phailin (figure 1(a)). The Sea Surface

Temperatures are cooled significantly along the storm track in the open ocean, but the

cooling is more prominent along the coast (figure 1(b)).

There are two possible explanations for surface cooling due to cyclones: extraction of

thermal energy from the surface due to evaporation, or wind induced vertical mixing

of the water column. This argument is based upon viewing the ocean as a two-layer

fluid; a warm upper layer, and a cold deeper layer. (The interface is referred to as the

main thermocline). The upper layer is relatively thick in October, so there must be a

great deal of vertical mixing to draw deep cold water to the surface. Along the shelf,

however, which the storm encounters as it approaches to the coast, the upper layer is

relatively thin. Therefore, with the same amount of vertical mixing, more cold water

can be drawn to the surface, and cooling is more substantial.

To substantiate the observed cooling in satellite derived SST, we have also collected

temperature and salinity profiles from Argo float data near vicinity of the Phailin

track (figure 2). There are three Argo Floats data available near vicinity of the Phailin

track with float ID Nos. 2901334, 2901335 and 2901327. Of which 2901335 is

available daily data, whereas 2901334 is once in five days starting from 07th October

2013 and 2901327 is available on 8th, 12th and 15th October 2013. The Mixed Layer

Depth (MLD) is computed based density criteria, the depth at which density is 0.125

at all three float locations and is presented in figure 2.

For all the three floats, the salinity and temperature profiles are presented in figure 3.

It is very clearly seen from all the profiles, that the surface cooling is observed on 12th

October, 2013 and at the same time the increase in surface salinity is seen on 12th,

indicating sub-surface cooled high saline waters appearing on the surface due to high

vertical mixing. It is also observed deepening of MLD on 12th October, 2013. It is

interesting to note that the surface salinity increase is quite high compared to surface

temperature cooling. Surface cooling observed is more than 2oC at Argo id 2901335

location after the passage of the storm (i.e. from 9th to 12th October 2013). The salinity

increase from 3.5 ppm, 4 ppm and 5.5 ppm at Argo id 2901334, 2901335 and

2901327 respectively during cyclone passage. From these observations (figure 3), it

is clear that the vertical mixing is dominant and observed stable mixed layer during

12th October 2013. There are fluctuation in these Argo float data due their locations

(2901335 on the track, 2901327 close to the track and 2901334 little away from the

track), as seen in figure 2, as well as coverage of data (one float, once in 5 days, one

float daily and the other on 8th, 12th and 15th October 2013).


Figure 2. The Phailin track with Argo floats Position; along with the Mixed Layer

Depth plotted against the dates for the profiles from Argo floats.

3.2 Wind, Wind Stress, Wind Stress Curl and Ekman Current

The wind, Wind Stress (WS) and Wind Stress Curl (WSC) products of the OSCAT

are studied with reference to the impact of cyclone Phailin. The wind vector and WS

are critically important for determining the large scale ocean circulation and transport.

Vector winds are needed to study the ocean and atmospheric process, like Ekman

transport, upwelling and mixed layer dynamics etc.


Figure 3. The salinity and temperature profiles for all the three Argo floats during the

cyclone Phailin period.


The high resolution (25 Km) wind velocities from OSCAT during the phailin cyclone

are studied. Though the wind speed measurement range of OSCAT is 4-24 m/s, the

wind speeds retrieved show as high as around 107 km/hr (29.6 m/s) on 12th during

landfall of Phailin. The estimated wind speeds reported by IMD are as high as 215

km/hr during landfall, which is double than the satellite estimation, and is mainly due

to saturation of the sensor. WS and WSC also increased all along the track from 8th to

12th and reached to maximum, 2.58 N/m2 and 9.86 N/m3 respectively at landfall

location on 12th October. The Tropical cyclone induced strong winds transfer the heat

from ocean to atmosphere through evaporation, which transport water vapour into the

troposphere. However, expected high evaporation may not be observed during the

cyclone due to intense cooling of surface, though strong winds are present. The

surface wind exerted stress lead to vertical mixing due to friction and generate

currents in the oceanic mixed layer. It is also known that the wind stress during

cyclone leads to move the waters away from the storm center through currents

generated over there and to maintain equilibrium cooled sub-surface waters comes up.

This process is known as storm generated ‘upwelling’. All these processes result in

cooling the sea surface all along the cyclone track and are discussed in the previous

section. The Phailin surface winds exert a stress on the ocean surface due to friction,

generating ocean currents in the oceanic mixed layer.

Under the assumption that the water currents are driven only by the transfer of

momentum from the wind, Ekman theory explains the theoretical state of circulation

and currents generated are known as Ekman Currents. Ekman motion describes the

wind-driven portion of circulation seen in the surface layer. Hence the Ekman

Currents are estimated using OSCAT wind during the Phailin cyclone. The maximum

Ekman current velocity observed was around 170 cm/s on 12th October 2013. It is

clearly seen that the waters moving away from the storm center and cooled sub-

surface waters comes up there, leading to sea surface cooling all along the cyclone

track.

3.3 Sea Level Pressure fields

The sea level pressure retrieved from OSCAT winds using UWPBL model during

Phailin Cyclone have been studied. Here we observed 10 mb pressure drop from 8th

to 13th October 2013. As per IMD, the pressure drop during the same period reported

to be 63-64 mb. Deep Depression is upgraded to Cyclone and subsequently to a

cyclonic storm named as Phailin. It is further strengthened and formed into a very

severe cyclonic storm by 10th and is further intensified with a central pressure of 994

mb and crossed the coast near Gopalpur on 12th October 2013. By nomenclature a

pressure drop of 5 to 9 mb with maximum sustained 3 minutes surface winds of

34 knots or more is called as cyclonic storm, which is clearly observed in our satellite

based pressure estimations from 8th to 10th October 2013. Though the IMD estimated

pressure values differ from satellite derived ones, the isobars maps generated are

closely matching with IMD reports during this cyclone (Figure 4). The pressure drop

at the cyclone centre is noticed to be low compared to estimated pressure drop

http://www.aoml.noaa.gov/hrd/tcfaq/D4.html


reported by IMD mainly due to saturation of winds (4-24 m/sec) measured by the

Oceansat Scatterometer sensor, which is input for the retrieval of pressure fields using

UWPBL model. The low pressure centers from UWPBL model derivatives are drawn

to built the cyclone track and found it is closer to the IMD track. Though the pressure

values differ from the IMD reported values, the increase in closed isobars from 8th to

12th October 2013 clearly indicate the intensity of cyclone.

Figure 4. Estimated pressures using UWPBL model from 8th to 13th October 2013 are

presented here. A low pressure system is present in north Andaman Sea with 1003 mb

pressure and for 12th October 2013, with a steep drop in pressure from surroundings

was observed and is as low as 993 mb on 12th October 2013.


3.4 Chlorophyll Concentration

The Ocean Colour Monitor (OCM) – 2 is one of the sensor onboard Oceansat-2

intended to estimate Chlorophyll-a as one of the parameters. The Chlorophyll

distribution along the cyclone track (according to IMD) has been computed before

and after the cyclone Phailin. From the analysis, it is observed that the chlorophyll-a

concentration has increased from 1.08 (before) to 7.06 mg/m3 after the cyclone

[Preethi et al., 2015].

3.5 Significant Wave Height

The significant wave heights were estimated using the SARAL-Altika and Jason-2

data during Phailin Cyclone i.e. on 12th October 2013. The Significant Wave Height

(SWH) variations against latitude during the pass of Saral-Altika-051 reveal high

SWH at 20o N latitude on 12th October, 2013 [Sasamal et al., 2015].

4. CONCLUSIONS

The cyclone induced cooling along the cyclone track is clearly seen in the satellite

derived Sea Surface Temperatures during the cyclone Phailin. Substantial cooling is

observed before the landfall of the cyclone. The cooling is a result of all the three

processes; namely evaporation, vertical mixing and upwelling. However, we observed

that the vertical mixing induced by upwelling is the dominant one.

The surface salinity increase is quite high compared to surface temperature cooling as

evident in the vertical profiles of Argo float temperature and salinity data.

The OSCAT winds, wind stress and wind stress curl impact is reflected in the ocean

surface by indicating intensive mixing to deeper waters.

It is clearly seen from the Ekman current that the waters are moving away from the

storm center leading upwelling to happen at the storm center.

The UWPBL model derived pressure fields are found useful in the construction of

cyclone track and intensity, through numerically they are underestimated due to

saturation of winds during cyclone.

Though, the evaporation rates are expected to be high during cyclone due to high

surface winds, but it is not as high as expected due to sudden surface cooling.

Finally, the winds are the major cause for upper ocean response to a moving storm.

Vertical mixing occurs because the cyclone’s surface winds exert a stress on the ocean

surface due to friction, generating ocean currents in the oceanic mixed layer which is

reflected in surface cooling, increase in surface salinity and high chlorophyll

concentration observed in passage of Phailin cyclone.

http://www.hurricanescience.org/glossary/?letter=M#glossaryword531

http://www.hurricanescience.org/glossary/?letter=F#glossaryword484


5. ACKNOWLEDGEMENTS

We express our gratitude to J. Patoux, PBL Research Group, Department of

Atmospheric Sciences, University of Washington, USA for his support rendered

during the execution of UWPBL model at NRSC and also his valuable suggestions.

Our sincere thanks to Saurabh Bansal former Scientist in OSG/ECSA/NRSC for his

continuous support. This work was carried out at National Remote Sensing Centre

(NRSC), as a part of Oceansat-II utilisation and NICES program. The Argo data were

collected and made freely available by the Coriolis project and programmes that

contribute to this study. TMI data are produced by Remote Sensing Systems and

sponsored by the NASA Earth Sciences Program is used in this study.

REFERENCES

[1] Adams, I. S., W. L. Jones, S. Vasudevan, and S. Soisuvarn (2005), Hurricane

wind retrievals using the SeaWinds scatterometer on QuikSCAT. Proc. Of

MTS/IEEE OCEANS 2005, Washington, D.C., Marine Technology Society and

the Oceanic Engineering Society of the IEEE, pp.2148-2150.

[2] Adams, I.S., C.C. Hennon, W. L. Jones, and K. A. Ahmad (2006), Evaluation

of hurricane ocean vector winds from WindSat. IEEE Trans. Geosci. Rem.

Sens., 44, pp.656 – 667.

[3] Aneesh, A. Lotliker, T. Srinivasa Kumar, Venkat Shesu Reddem and Shailesh

Nayak (2014), Cyclone Phailin enhanced the productivity following its

passage: evidence from satellite data. Current Sci., 106(3), pp.360-361

[4] Atlas, R. M., R. N. Hoffman, S. C. Bloom, J. C. Jusem, and J. Ardizzone

(1996), A multiyear global surface wind velocity dataset using SSM/I wind

observations. Bull. Amer. Meteor. Soc., 77, pp.869-882.

[5] Atlas, R., and R.N. Hoffman (2000), The use of satellite surface wind data to

improve weather analysis and forecasting at the NASA Data Assimilation

Office. Satellites, Oceanography and Society, Halpern, D., Elsevier

Oceanography Series,

[6] Isaksen, L., and A. Stoffelen (2000), ERS-Scatterometer wind data impact on

ECMWF's tropical cyclone forecasts. IEEE Trans. Geosci. Rem. Sens., 38,

pp.1885-1892.

[7] Liu, W. T. and X. Xie (2008), Ocean-atmosphere momentum coupling in the

Kuroshio Extension observed from space. J. Oceanogr., 64, pp.631-637.

[8] Peter, G. Black, and L.K. Shay (1995). Observed sea surface temperature

variability in tropical cyclones: Implications for structure and intensity change.

Preprints, 21st Conference on Hurricanes and Tropical Meteorology, Miami,

FL, April 24-28, 1995. American Meteorological Society, Boston, 603-604.

[9] Patoux, J., R. C. Foster, and R. A. Brown (2003), Global Pressure Fields from

Scatterometer Winds. Journal of Applied Meteorology, 42, 813-826


[10] Preethi Latha, T., K. H. Rao, P. V. Nagamani, E. Amminedu, S. B.

Choudhury, C. B. S. Dutt, V. K. Dadhwal (2015), Impact of Super Cyclone

PHAILIN on chlorophyll-a concentration and productivity in the Bay of

Bengal. International Journal of Geoscience, Vol. 6(5), pp.473-480.

[11] Purnachand, Ch., M. V. Rao, I. V. Ramana, M. M. Ali, J. Patoux, and

M.A.Bourassa (2014), Estimation of Sea-Level Pressure Fields during

Cyclone Nilam from Oceansat-2 Scatterometer Winds. Atmos. Sci. Let. 15,

pp.65-71.

[12] Purnachand, Ch., I. V. Ramana, M. M. Ali, K. H. Rao, P. N. Sridhar, C. B. S.

Dutt and M. V. Rao (2015), Retrieval and Validation of Pressure Fields from

Scatterometer Winds. Tech. Rep. No. NRSC – ECSA – OSG – NOV – 2014 –

TR – 667, NRSC, Hyderabad, pp. 27.

[13] Rao, M. V., B. Jena, I. V. Ramana and M. M. Ali (2002), Remote Sensing of

Sea Surface cooling by a Tropical Cyclone. In: Proc. of International

conference of ISPRS held during Dec. 3rd-6th at Hyderabad, India, 34(7),

pp.63-68.

[14] Sadhuram, Y. (2004), Record decrease of sea surface temperature following

the passage of a super cyclone over the Bay of Bengal, Current Sci., 86( 3),

pp.383-384.

[15] Sasamal, S. K., B. Sourabh, K. H. Rao, C. B. S. Dutt, and V. K. Dadhwal

(2015). OSCAT Wind Stress and Wind Stress Curl during the Bay of Bengal

Tropical Cyclone ‘Mahasen’, International Journal of Engineering Science

and Innovative Technology, 4(2), pp.152-162.

[16] Sasamal, S. K., Sourabh Bansal, C. B. S. Dutt, V. K. Dadhwal (2015), Use of

SARAL AltiKa geophysical products towards the study of ‘Phailin’.

International Journal of Engineering Science and Innovative Technology, Vol.

4(2), pp. 125-134.

[17] Sourabh, B., S. K. Sasamal, K. H. Rao, C. B. S. Dutt, (2014). Indian Ocean

Surface Currents using OSCAT and Saral-Altika. Tech. Rep. No. NRSC –

ECSA – OSG – NOV – 2014 – TR – 659, NRSC, Hyderabad, pp. 21.

[18] Sourabh, B., S. K. Sasamal, Chiranjivi Jayaram, T.V.S. Udaya Bhaskar, D.

Swain (2014), OSCAT Wind Stress and Wind Stress Curl Products. Tech.

Rep. No. NRSC – ECSA – OSG – NOV – 2014 – TR – 661, NRSC, Hyderabad,

pp. 18.

[19] Shiah, F. K., S.W. Chung, S.J. Kao, G. C. Gong, K. K. Liu (2000),

Biological and hydrographical responses to tropical cyclones (typhoons) in the

continental shelf of the Taiwan Strait. Cont. Shelf Res. 20, pp.2029–2044.

[20] Shuwen Zhang, Lingling Xie , Yijun Hou, Hui Zhao, Yiquan Qi, and Xiaofei

Yi (2014). Tropical storm-induced turbulent mixing and chlorophyll-a

enhancement in the continental shelf southeast of Hainan Island, Journal of

Marine Systems, 129, pp.405-414.

http://www.sciencedirect.com/science/article/pii/S0924796313001954







http://www.sciencedirect.com/science/journal/09247963

http://www.sciencedirect.com/science/journal/09247963


[21] Stramma, L., P. Cornillon (1986), Satellite observation of Sea Surface Cooling

by Hurricanes, J. Geophys. Res., 91, pp.5031-5035.

[22] Subramanyam Bulusu, K. H. Rao, N. Srinivasa Rao, V. S. N. Murthy, and

Ryan J. Sharp (2002), Influence of a tropical Cyclone on Chlorophyll-a

concentration in the Arabian Sea, Geophysical Research Letters, 29(22),

pp.2051-2065.

[23] Suetsugu, M. Kawamura, H., and Nishihama, S (2000), Sea Surface cooling

caused by typhoons in the Western North Pacific Ocean. PORSEC

Proceedings, Goa, India, 1, pp.258-262.

[24] Yablonsky, R. M., and I. Ginis (2013), Impact of a warm ocean eddy's

circulation on hurricane-induced sea surface cooling with implications for

hurricane intensity, Monthly Weather Review, 141(3), pp. 997-1021.

Influence of cyclone Phailin on the Upper Ocean over Bay of Bengal · 2017-08-14 · Influence of...

Documents

Transcript of Influence of cyclone Phailin on the Upper Ocean over Bay of Bengal · 2017-08-14 · Influence of...