Jensen
Tommy G.
Jensen
Tommy G.
No Thumbnail Available
Search Results
Now showing
1 - 3 of 3
-
ArticleCoupled ocean–atmosphere modeling and predictions(Sears Foundation for Marine Research, 2017-05-01) Miller, Arthur J. ; Collins, Matthew ; Gualdi, Silvio ; Jensen, Tommy G. ; Misra, Vasu ; Pezzi, Luciano Ponzi ; Pierce, David W. ; Putrasahan, Dian ; Seo, Hyodae ; Tseng, Yu-HengKey aspects of the current state of the ability of global and regional climate models to represent dynamical processes and precipitation variations are summarized. Interannual, decadal, and global-warming timescales, wherein the influence of the oceans is relevant and the potential for predictability is highest, are emphasized. Oceanic influences on climate occur throughout the ocean and extend over land to affect many types of climate variations, including monsoons, the El Niño Southern Oscillation, decadal oscillations, and the response to greenhouse gas emissions. The fundamental ideas of coupling between the ocean-atmosphere-land system are explained for these modes in both global and regional contexts. Global coupled climate models are needed to represent and understand the complicated processes involved and allow us to make predictions over land and sea. Regional coupled climate models are needed to enhance our interpretation of the fine-scale response. The mechanisms by which large-scale, low-frequency variations can influence shorter timescale variations and drive regionalscale effects are also discussed. In this light of these processes, the prospects for practical climate predictability are also presented.
-
ArticleASIRI : an ocean–atmosphere initiative for Bay of Bengal(American Meteorological Society, 2016-11-22) Wijesekera, Hemantha W. ; Shroyer, Emily L. ; Tandon, Amit ; Ravichandran, M. ; Sengupta, Debasis ; Jinadasa, S. U. P. ; Fernando, Harindra J. S. ; Agrawal, Neeraj ; Arulananthan, India K. ; Bhat, G. S. ; Baumgartner, Mark F. ; Buckley, Jared ; Centurioni, Luca R. ; Conry, Patrick ; Farrar, J. Thomas ; Gordon, Arnold L. ; Hormann, Verena ; Jarosz, Ewa ; Jensen, Tommy G. ; Johnston, T. M. Shaun ; Lankhorst, Matthias ; Lee, Craig M. ; Leo, Laura S. ; Lozovatsky, Iossif ; Lucas, Andrew J. ; MacKinnon, Jennifer A. ; Mahadevan, Amala ; Nash, Jonathan D. ; Omand, Melissa M. ; Pham, Hieu ; Pinkel, Robert ; Rainville, Luc ; Ramachandran, Sanjiv ; Rudnick, Daniel L. ; Sarkar, Sutanu ; Send, Uwe ; Sharma, Rashmi ; Simmons, Harper L. ; Stafford, Kathleen M. ; St. Laurent, Louis C. ; Venayagamoorthy, Subhas K. ; Venkatesan, Ramasamy ; Teague, William J. ; Wang, David W. ; Waterhouse, Amy F. ; Weller, Robert A. ; Whalen, Caitlin B.Air–Sea Interactions in the Northern Indian Ocean (ASIRI) is an international research effort (2013–17) aimed at understanding and quantifying coupled atmosphere–ocean dynamics of the Bay of Bengal (BoB) with relevance to Indian Ocean monsoons. Working collaboratively, more than 20 research institutions are acquiring field observations coupled with operational and high-resolution models to address scientific issues that have stymied the monsoon predictability. ASIRI combines new and mature observational technologies to resolve submesoscale to regional-scale currents and hydrophysical fields. These data reveal BoB’s sharp frontal features, submesoscale variability, low-salinity lenses and filaments, and shallow mixed layers, with relatively weak turbulent mixing. Observed physical features include energetic high-frequency internal waves in the southern BoB, energetic mesoscale and submesoscale features including an intrathermocline eddy in the central BoB, and a high-resolution view of the exchange along the periphery of Sri Lanka, which includes the 100-km-wide East India Coastal Current (EICC) carrying low-salinity water out of the BoB and an adjacent, broad northward flow (∼300 km wide) that carries high-salinity water into BoB during the northeast monsoon. Atmospheric boundary layer (ABL) observations during the decaying phase of the Madden–Julian oscillation (MJO) permit the study of multiscale atmospheric processes associated with non-MJO phenomena and their impacts on the marine boundary layer. Underway analyses that integrate observations and numerical simulations shed light on how air–sea interactions control the ABL and upper-ocean processes.
-
ArticleNorthern Arabian Sea Circulation-Autonomous Research (NASCar) : a research initiative based on autonomous sensors(Oceanography Society, 2017-06) Centurioni, Luca R. ; Hormann, Verena ; Talley, Lynne D. ; Arzeno, Isabella B. ; Beal, Lisa M. ; Caruso, Michael J. ; Conry, Patrick ; Echols, Rosalind ; Fernando, Harindra J. S. ; Giddings, Sarah N. ; Gordon, Arnold L. ; Graber, Hans C. ; Harcourt, Ramsey R. ; Jayne, Steven R. ; Jensen, Tommy G. ; Lee, Craig M. ; Lermusiaux, Pierre F. J. ; L’Hegaret, Pierre ; Lucas, Andrew J. ; Mahadevan, Amala ; McClean, Julie L. ; Pawlak, Geno ; Rainville, Luc ; Riser, Stephen C. ; Seo, Hyodae ; Shcherbina, Andrey Y. ; Skyllingstad, Eric D. ; Sprintall, Janet ; Subrahmanyam, Bulusu ; Terrill, Eric ; Todd, Robert E. ; Trott, Corinne ; Ulloa, Hugo N. ; Wang, HeThe Arabian Sea circulation is forced by strong monsoonal winds and is characterized by vigorous seasonally reversing currents, extreme differences in sea surface salinity, localized substantial upwelling, and widespread submesoscale thermohaline structures. Its complicated sea surface temperature patterns are important for the onset and evolution of the Asian monsoon. This article describes a program that aims to elucidate the role of upper-ocean processes and atmospheric feedbacks in setting the sea surface temperature properties of the region. The wide range of spatial and temporal scales and the difficulty of accessing much of the region with ships due to piracy motivated a novel approach based on state-of-the-art autonomous ocean sensors and platforms. The extensive data set that is being collected, combined with numerical models and remote sensing data, confirms the role of planetary waves in the reversal of the Somali Current system. These data also document the fast response of the upper equatorial ocean to monsoon winds through changes in temperature and salinity and the connectivity of the surface currents across the northern Indian Ocean. New observations of thermohaline interleaving structures and mixing in setting the surface temperature properties of the northern Arabian Sea are also discussed.