Exploring the upper ocean

Tandon Laboratory at UMass Dartmouth

Author: sid (page 1 of 5)

Breakthrough Insights Emerged from MISO-BOB Campaign Aircraft Observations Over Indian Ocean

In a pioneering mission, a group of researchers (including Dr Amit Tandon) participating the Monsoon Intra-Seasonal Oscillations in the Bay of Bengal (MISO-BOB) field campaign, funded by the US Office of Naval Research, has provided groundbreaking insights into the tropical supercluster dynamics over the equatorial Indian Ocean.

In a study led by Dr Phadtare from University of Notre Dame, observations were collected using a WC-130J aircraft operated by Air Force’s 53rd Weather Reconnaissance Squadron, which delved into the heart of the action during the summer monsoon seasons of 2018 . Dropsonde observations revealed a captivating variance of zonal winds within the supercluster. The upper troposphere favored easterlies, while the lower troposphere exhibited prevailing westerlies, creating a unique atmospheric stratification just below the 0°C level.

Of particular interest was the cold pool at the center of the supercluster. It maintained a consistent easterly component, with the coldest temperatures registering a 2.5°C drop at the center. The depth of the cold pool varied, reaching its deepest at the rear/western end and shallower at the front/eastern end, measuring at around 300 meters. A key revelation was the identification of the level of free convection (LFC) at the front end. On the eastern flank, researchers observed zonal convergence between the westerlies within the supercluster and ambient easterlies at lower tropospheric levels. This suggested the uplifting of conditionally unstable air parcels above LFC due to convergence, rather than the influence of the cold pool.

Conversely, the western flank exhibited low-level zonal divergence, further supporting the concept of ‘self-similarity’ between mesoscale convective systems and large-scale waves.

The MISO-BOB campaign’s findings provide a leap forward in our understanding of monsoon intra-seasonal oscillations. The data obtained from these aircraft observations holds promise for refining climate models and advancing our ability to predict tropical weather patterns, contributing to more effective global weather predictions in the future.

More information about this article can be found here. Congratulations Dr Phadtare and team!


A schematic of the observations taken by the WC130J aircraft in the supercluster. (Adapted from Figure 10 of Phadtare et al. 2024)

Patrick Pasteris defends his Master’s thesis

We are thrilled to announce that Patrick Pasteris, a Master’s student in Tandon Lab, defended his master’s thesis on November 10, 2023. He worked on the Aurelia Upper Ocean Profiler (UOP), a revolutionary solution to the financial constraints plaguing upper ocean observations, for his thesis. Inspired by the Aurelia jellyfish genus, the Aurelia UOP is engineered for upper-ocean profiling within the top 200 meters, utilizing a unique buoyancy engine mechanism and integrating wireless connectivity.

Patrick’s journey with this profiler began with a 2016 Senior Capstone project, which saw the evolution of a groundbreaking idea into the Aurelia UOP. Mentoring five multidisciplinary Capstone teams and guided by Dr. Amit Tandon, Professor of Mechanical Engineering, alongside committee members Dr. Alice Pietri and Dr. John Buck, Pasteris successfully navigated the challenges of developing this affordable and user-friendly oceanic research device.

The Aurelia UOP Lite, the culmination of Patrick’s thesis research which involved a series of tank and ocean tests, is a compact 10lb device capable of reaching depths of 50m. This innovation not only signifies a significant milestone in oceanic research but also holds the promise of advancing weather forecasting and enhancing maritime safety through cost-effective upper ocean monitoring. The Aurelia UOP Lite stands as a testament to the power of interdisciplinary collaboration and ingenuity, paving the way for a new era in scientific exploration.

Congratulations Patrick!


Patrick (left) with his thesis committee members: Dr Amit Tandon (first from right), Dr John Buck (second from right) and Dr Alice Pietri (virtual)

Filipe featured on the UMassD feature story

Dr. Filipe Pereira was recently featured in the Feature stories section of UMassD. Find more about his motivating academic journey so far, which had its own challenges, as well as what the future holds for him here (including his upcoming appointment in Scripps Institution of Oceanography as a UC president’s fellow!).

Congratulations Filipe!

Vicky speaks at 2023 ACCOMPLISH Scholarship Award event

One of the Lab Alumni, Viktoriya Balabanova, recently spoke in an event to welcome 2023 ACCOMPLISH Scholarship Awardees and talk about the Scholarship. The ACCOMPLISH program from UMassD, funded by NSF, aims to provide a multi-faceted financial and social support and contextualized computing-centered educational framework for eligible STEM students to propel them into the nation’s high-quality STEM workforce. In her talk (video at the end of this article) , Vicky talks about how this award helped her to be inspired towards the importance of computational knowledge, work on such projects in Physics (including her BS thesis work in Tandon lab as a part of WHOI-UMassD Blue Economy internship) and graduate sooner. Vicky also talks about the procedure to apply for this scholarship. More about the program can be found here

Tandon lab members participate in the EKAMSAT Pilot cruise 2023

(L-R) Sid Kerhalkar, Prof. Amit Tandon and Debarshi Sarkar with the R/V Roger Revelle docked in the Mormugao port.

Professor Amit Tandon, Siddhant (Sid) Kerhalkar (PhD candidate) and Debarshi Sarkar (incoming PhD student) were aboard the US research vessel Roger Revelle for the pilot cruise of EKAMSAT (Enhancing Knowledge of the Arabian Sea Marine Environment through Science and Advanced Training) in the Arabian Sea, June 09-26, 2023. EKAMSAT is a USA-India international collaboration. The USA team is funded by the US Office of Naval Research for the air-sea interaction, marine meteorology, and physical oceanography components, and the Indian team is funded by the Indian Ministry of Earth Sciences (MoES). During the pilot, the two teams worked collaboratively to understand the evolution of the mini-warm pool in the Arabian Sea and its connection to the Indian Summer Monsoon. In addition, three NASA-funded scientists also joined this cruise to examine the ocean ecosystem during this cruise.

After reaching Goa during the first week of June, the three of them were joined onboard by 20 other scientists from institutions such as the University of Washington, Scripps Institution of Oceanography, Woods Hole Oceanographic Institution, Columbia University, University of Notre Dame, Consiglio Nazionale delle Ricerche (Italy), NOAA Center for Weather and Climate Prediction, Penn State University, Whatcom Community College and Indian institutions  INCOIS, NIOT, NCMRWF, and IITM-Pune. The ship made port calls in Goa, India for this experiment, with Prof. Craig Lee from U of Washington as the chief scientist of the cruise. The ship left the Mormugao port on the night of June 08. 2023, while the Arabian sea was  being churned by cyclone Biparjoy resulting in a very high wave and wind state. To commemorate the beginning of the pilot cruise and the project, the ship was virtually flagged by the MoES secretary. Due to the passage of Tropical cyclone Biparjoy, the team shifted its target station southward from 14.6 N, 69 E (NIOT AD07 mooring) to 12.06 N, 67.75 E (100 km offshore of AD 08 mooring). This meant that the ship had a longer transit time, which was made tougher due to rough waves from the cyclone, making most of the members sea-sick for the initial few days.

Virtual flag-off of EKAMSAT cruises (Source: INCOIS Twitter)

In addition to learning how to operate out of Goa, the scientific goals of the pilot cruise were focused on understanding the processes that governed the evolution of stratification around the target station (one-dimensional versus the lateral processes) before obtaining clean simultaneous measurements of atmospheric variables and vertical ocean profiles to measure accurate air-sea fluxes, including the importance of waves and swell for these fluxes. In order to obtain clean atmospheric measurements, the ship needs to point into the wind. The passage of the cyclone also inspired secondary goals of understanding the role of waves in driving the mixing and sampling across the cyclone wake to unearth the processes behind restratifying the cold dense wake created by the cyclone .

Cruise Map of EKAMSAT Pilot 2023

(Clockwise from Top Left): A pretty sunset in Arabian Sea, Prof Tandon and Sid during the watch, CTD rosette underwater, CTD rosette being deployed, Science discussions in the hope of a rain event, uCTD probe underwater

This cruise was a major learning experience for the participating student members of Tandon lab: Sid and Debarshi. In addition to both of them participating in uCTD watches and helping with typical deployment-recovery of other gear when needed,  Sid was mostly in charge of preliminary processing and visualization of the ship through-flow, lower atmospheric variables, and wave data. Debarshi, who was participating in his first scientific cruise, was tasked to process and plot the profiles from the CTD casts. The data and ideas from this experiment will eventually be used for parts of their respective dissertations. Along with serving on watches, Professor Tandon provided overall guidance, as well as conceptual inputs to the cruise along with senior scientist Professor Janet Sprintall and Chief scientist Professor Craig Lee.


EKAMSAT Pilot Cruise 2023 Science Team

Sid also documented some of the science activities on the cruise using his action camera (see the video above). Overall, the cruise was very successful and the team members are now looking forward to analyzing the dataset and working on the science further.

Sid featured on the UMassD feature story

Sid was recently featured in the Feature stories section of UMassD. Find more about his motivation for pursuing his doctoral dissertation in the Tandon Lab, his research interests, his participation in research cruises and his favorite things about the lab and UMassD in the article here.

Congratulations Sid!

Listening for Rain: Principal Component Analysis Unlocks New Insights

A group of researchers including Prof. Amit Tandon have unveiled an innovative approach to studying rainfall patterns in a recent article published in the Journal of the Acoustical Society of America. By harnessing the power of Principal Component Analysis (PCA) and acoustic data using hydrophones, scientists are pushing the boundaries of detecting precipitation. Traditional methods of tracking rainfall rely on weather radar and satellite imagery, which can be limited in remote or heavily vegetated areas. Given that more than 75% of the Earth’s precipitation occurs over the ocean and satellite measurements have large uncertainties, meteorologists and climatologists seek alternate rain detection methods to further improve weather prediction models.

This paper uses data from a weather station, located in the SMAST pier in New Bedford as a reference and simultaneously listened to the rainfall from the hydrophones on the pier to develop a new PCA based rain detection algorithm which exploits broadband acoustic data.

The data collection setup in SMAST pier. The hydrophones are 1 and 2 m below the low-tide line at the end of the pier. Weather measurements occur on the pier itself.

Top (a): Rain and wind recorded by the weather station for a few days in August 2021. Middle (b): A spectrogram of audio data recorded by a pier-mounted hydrophone during this time. Bottom (c): A banded plot showing whether a datapoint is usable in this experiment.

More information about this article can be found here. Congratulations Dr Mallary and team!

Sid presents his PhD work at IITM Pune

Siddhant (Sid) Kerhalkar, a PhD candidate in Tandon labs, presented a seminar on his research on Diurnal Warm Layers (DWLs) at Indian Institute of Tropical Meteorology Pune on July 11, 2023.  Attended by many distinguished scientists there, Sid was able to convince the audience about the importance of DWLs in monsoon representation and present observational evidence of the lateral variability over O(30 km) in these layers, arguably due to the spatial gradients in the wind speed patterns and background stratification over similar length scales in the Bay of Bengal.

Sid also utilized this time to understand the work various research various groups do at IITM Pune as well as understand how observational oceanographers like him could help the modeling community in developing a better understanding of monsoons.

Sid presenting at IITM Pune

Iury and Sid attend the ONR Code 322 Workshop held in Arlington, VA on May 22-23, 2023

In an endeavor to navigate the careers in ocean research, Iury and Sid participated in the ONR Code 322 Graduate Student and Postdoc Workshop, hosted in Arlington, VA, on May 22-23, 2023. This comprehensive career workshop illuminated the diverse array of  opportunities, showcased the pivotal functions of the Office of Naval Research (ONR), emphasized the art of science communication, underscored the importance of safe and inclusive fieldwork practices, and facilitated networking among peers and potential employers. This workshop was attended by various officials from U.S. Navy, ONR, NOAA, NSF, NRL etc.

This workshop helped the attendees see their research as contributing to the broader society.  Moreover, the workshop’s focus on science communication resonated deeply and recognized its pivotal role in conveying the significance of their work to diverse audiences.

Finally, the networking sessions held great value as they allowed Iury and Sid to connect with potential employers and peers. These connections opened doors to opportunities, form mentorship and collaborations.


Iury and Sid participating in the ONR Code 322 Workshop

Vicky featured on the UMassD feature story

Viktoriya was recently featured in the Feature stories section of UMassD. Find more about the different avenues she pursued before doing her undergraduate thesis in the Tandon Lab, in the article here.

Congratulations Vicky!

Older posts
Skip to toolbar