Modeling the Pacific Ocean on the Computer [Video]

In fluid dynamics, motions on and below the ocean surface, such as surface and internal (underwater) waves, or along the ocean floor are modeled. Before we can simulate the ocean on a computer, it has to be mathematically divided into separate "control volumes" for which we impose the classic physical conservation principles for mass, momentum, energy, or salinity. Sometimes, billions of these discrete boxes are coupled in a single model. Computer models alongside satellite or field study data, as well as some laboratory experiments help us understand how large-scale events such as underwater avalanches can impair underwater infrastructure such as telecommunication cables or pipelines, how gas and oil reservoirs form below the ocean floor, or how ocean transport of heat, salt, and CO~2~ affects global climate, ocean temperature, and acidification. Scalability is important for this type of modeling, since computational investigations of ocean flows often start with small systems that are then upscaled into much larger-scale phenomena. Video available at: https://vimeo.com/52739849

Observing and Modeling the Pacific Ocean [Video]

Marine scientists incorporate a wide array of observations and models to understand the oceans, their dynamics, and the life they support. The development of new sensing technologies such as satellites, gliders, and robotic floats, as well as increasing public interest and funding for projects to investigate the ocean’s role in climate change, has transformed marine sciences into "big data" sciences. But the observational scientist still faces numerous obstacles in measuring ocean characteristics such as sea surface height, currents, temperature, salinity, water color, ocean chemistry, and undersea life: electromagnetic radiation does not readily penetrate its waters, which makes it harder to conduct observations and communicate with underwater instruments, and because oceans are full of life, so called "biofouling" is a challenge to observing, especially in the sun-lit layers near the surface. Nevertheless, new technologies such as robotic vehicles and new sensors are enabling observations throughout the ocean water column. These technologies, coupled with rapidly advancing ocean models, are revolutionizing our understanding of the marine biosphere. $$Image: UCSB undergraduates Andie Rupprecht and Sean Jawetz recover a robotic stand-up paddle board used for measuring ocean currents. Photograph by Libe Washburn.$$ Video available: https://vimeo.com/52739734

PICES Press, Vol. 8, No. 2, July 2000

Beyond El Nino Conference The status of the Bering Sea: June - December, 1999 The state of the western North Pacific in the second half of 1999 The state of the eastern North Pacific since autumn 1999 Project Argo Report of the ICES Zooplankton Ecology Working Group/PICES meeting Shark abundance increases in the Gulf of Alaska PICES Lower Trophic Level Modeling Workshop, Nemuro On the third meeting of the LMR-GOOS Panel Ocean Ecology of Juvenile Salmonids along the North American Coas

Modeling North Pacific temperature and pressure changes from coastal tree-ring chronologies

Climate modeling using coastal tree-ring chronologies has yielded the first summer temperature reconstructions for coastal stations along the Gulf of Alaska and the Pacific Northwest. These land temperature reconstructions are strongly correlated with nearby sea surface temperatures, indicating large-scale ocean-atmospheric influences. Significant progress has also been made in modeling winter land temperatures and sea surface temperatures from coastal and shipboard stations. In addition to temperature, the pressure variability center over the central North Pacific Ocean (PAC), which is related to the strength and location of the Aleutian Low pressure system, could be extended using coastal tree rings

An empirical parameterization of subsurface entrainment temperature for improved SST anomaly simulations in an intermediate ocean model

An empirical model for the temperature of subsurface water entrained into the ocean mixed layer (Te) is presented and evaluated to improve sea surface temperature anomaly (SSTA) simulations in an intermediate ocean model (IOM) of the tropical Pacific. An inverse modeling approach is adopted to estimate Te from an SSTA equation using observed SST and simulated upper-ocean currents. A relationship between Te and sea surface height (SSH) anomalies is then obtained by utilizing a singular value decomposition (SVD) of their covariance. This empirical scheme is able to better parameterize Te anomalies than other local schemes and quite realistically depicts interannual variability of Te, including a nonlocal phase lag relation of Te variations relative to SSH anomalies over the central equatorial Pacific. An improved Te parameterization naturally leads to better depiction of the subsurface effect on SST variability by the mean upwelling of subsurface temperature anomalies. As a result, SSTA simulations are significantly improved in the equatorial Pacific; a comparison with other schemes indicates that systematic errors of the simulated SSTAs are significantly small—apparently due to the optimized empirical Teparameterization. Cross validation and comparisons with other model simulations are made to illustrate the robustness and effectiveness of the scheme. In particular it is demonstrated that the empirical Te model constructed from one historical period can be successfully used to improve SSTA simulations in another

Paleoclimate evolution of the North Pacific Ocean during the late Quaternary: Progress and challenges

High- and low-latitude climatic processes in the North Pacific Ocean are important components of the global climate system. For example, the interplay among North Pacific atmospheric circulation, ocean circulation, and biological productivity affects atmospheric carbon dioxide levels and marine oxygen concentrations. Here we review recent research on the North Pacific paleoclimatic and paleoceanographic evolution during the late Quaternary and its response to external forcings such as orbital insolation, ice-sheet extent, and greenhouse gas concentrations. First, we summarize the principles and application of relative paleointensity as a critical chronological tool in North Pacific paleoclimate research. Second, we illustrate the latest discoveries on the interaction between North Pacific Intermediate Water formation and high-to-low latitude teleconnection processes. Third, recent progress in linking dust fluxes and marine productivity and their global significance for the carbon cycle are presented. Finally, several key scientific problems are highlighted for future research on ocean-atmosphere-climate interactions in the North Pacific, pointing to the importance of combining paleo-records and modeling simulations. Overall, this review also aims to provide a broad insight into possible future changes of ocean-atmosphere circulation in the North Pacific region under a rapidly warming climate

Bibliography update on the California current system and related mesoscale ocean modeling

This bibliography updates the following publication: Mooers, C.N.K., R.G. Williams, K.C. Vierra and G.R. Halliwell, Jr., 1980. Bibliogrphy for the Coastal Circulation of the Eastern North Pacific. College of Marine Studies, University of Delaware, 77 pp.This bibliography has been prepared for use in the Ocean Prediction Through Observation, Modeling and Analysis (OPTOMA) program. It updates the 1980 publication "Bibliography for the Coastal Ciruclation of the Eastern North Pacific." In addition, mesoscale ocean modeling references related to the California Current System has been included.Prepared for: Office of Naval Research, Environmental Sciences Directorate (Code 420) Arlington, VAhttp://archive.org/details/bibliographyupda00batt61153N N0001484 WR24051NAApproved for public release; distribution is unlimited

Report of the 2005 Workshop on Ocean Ecodynamics Comparison in the Subarctic Pacific

I. Scientific Issues Posed by OECOS II. Participant Contributions to the OECOS Workshop A. ASPECTS OF PHYTOPLANKTON ECOLOGY IN THE SUBARCTIC PACIFIC Microbial community compositions by Karen E. Selph Subarctic Pacific lower trophic interactions: Production-based grazing rates and grazing-corrected production rates by Nicholas Welschmeyer Phytoplankton bloom dynamics and their physiological status in the western subarctic Pacific by Ken Furuya Temporal and spatial variability of phytoplankton biomass and productivity in the northwestern Pacific by Sei-ichi Saitoh, Suguru Okamoto, Hiroki Takemura and Kosei Sasaoka The use of molecular indicators of phytoplankton iron limitation by Deana Erdner B. IRON CONCENTRATION AND CHEMICAL SPECIATION Iron measurements during OECOS by Zanna Chase and Jay Cullen 25 The measurement of iron, nutrients and other chemical components in the northwestern North Pacific Ocean by Kenshi Kuma The measurement of iron, nutrients and other chemical components in the northwestern North Pacific Ocean by Kenshi Kuma C. PHYSICAL OCEANOGRAPHY, FINE-SCALE DISTRIBUTION PATTERNS AND AUTONOMOUS DRIFTERS The use of drifters in Lagrangian experiments: Positives, negatives and what can really be measured by Peter Strutton The interaction between plankton distribution patterns and vertical and horizontal physical processes in the eastern subarctic North Pacific by Timothy J. Cowles D. MICROZOOPLANKTON Microzooplankton processes in oceanic waters of the eastern subarctic Pacific: Project OECOS by Suzanne Strom Functional role of microzooplankton in the pelagic marine ecosystem during phytoplankton blooms in the western subarctic Pacific by Takashi Ota and Akiyoshi Shinada E. MESOZOOPLANKTON Vertical zonation of mesozooplankton, and its variability in response to food availability, density stratification, and turbulence by David L. Mackas and Moira Galbraith Marine ecosystem characteristics and seasonal abundance of dominant calanoid copepods in the Oyashio region by Atsushi Yamaguchi, Tsutomu Ikeda and Naonobu Shiga OECOS: Proposed mesozooplankton research in the Oyashio region, western subarctic Pacific by Tsutomu Ikeda Some background on Neocalanus feeding by Michael Dagg Size and growth of interzonally migrating copepods by Charles B. Miller Growth of large interzonal migrating copepods by Toru Kobari F. MODELING Ecosystem and population dynamics modeling by Harold P. Batchelder III. Reports from Workshop Breakout Groups A. PHYSICAL AND CHEMICAL ASPECTS WITH EMPHASIS ON IRON AND IRON SPECIATION B. PHYTOPLANKTON/MICROZOOPLANKTON STUDIES C. MESOZOOPLANKTON STUDIES IV. Issues arising during the workshop A. PHYTOPLANKTON STOCK VARIATIONS IN HNLC SYSTEMS AND TROPHIC CASCADES IN THE NANO AND MICRO REGIMES B. DIFFERENCES BETWEEN EAST AND WEST IN SITE SELECTION FOR OECOS TIME SERIES C. TIMING OF OECOS EXPEDITIONS D. CHARACTERIZATION OF PHYSICAL OCEANOGRAPHY V. Concluding Remarks VI. References (109 page document

Remote Ocean Forcing on Interannual-to-Decadal Climate Variability through Inter-Basin Interactions

This dissertation explores the connection between ocean basins through the atmosphere by employing observational data analyses and a climate modeling approach. Sea surface temperature changes in the tropical Pacific, known as the El Niño Southern Oscillation, can influence worldwide weather and sea surface temperatures in other ocean basins. For instance, tropical Pacific sea surface temperatures can impact the Atlantic and Indian Oceans through airflow changes along the equator. However, Atlantic and Indian Ocean sea surface temperature changes can also influence the tropical Pacific through similar processes. Therefore, it is challenging to identify the mechanisms of these remote connections between ocean basins due to two-way interconnections. To better understand how ocean basins are connected by the atmosphere, this dissertation uses climate models to simulate the climate response from ocean forcing. Results in this dissertation show that the three tropical oceans are more tightly connected than previously thought. After introducing the dissertation in Chapter 1, Chapter 2 shows how the Atlantic Ocean can cause long-lasting changes in Australia rainfall through teleconnections. Chapter 3 reveals that Atlantic sea surface temperatures can influence north Pacific sea surface temperatures through remote teleconnections. Lastly, Chapter 4 explores trends in rainfall in the Pacific and the Indian Ocean from the 1980s to the 2010s. The results in this dissertation provide a path for-ward to increase the forecasting capability of the El Niño Southern Oscillation and help the climate science community enhance our understanding of climate variability

Numerical investigations of seasonal and interannual variability of North Pacific Subtropical Mode Water and its implications for Pacific climate variability

Author Posting. © American Meteorological Society, 2011. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 24 (2011): 2648–2665, doi:10.1175/2010JCLI3435.1.North Pacific Subtropical Mode Water (NPSTMW) is an essential feature of the North Pacific subtropical gyre imparting significant influence on regional SST evolution on seasonal and longer time scales and, as such, is an important component of basin-scale North Pacific climate variability. This study examines the seasonal-to-interannual variability of NPSTMW, the physical processes responsible for this variability, and the connections between NPSTMW and basin-scale climate signals using an eddy-permitting 1979–2006 ocean simulation made available by the Estimating the Circulation and Climate of the Ocean, Phase II (ECCO2). The monthly mean seasonal cycle of NPSTMW in the simulation exhibits three distinct phases: (i) formation during November–March, (ii) isolation during March–June, and (iii) dissipation during June–November—each corresponding to significant changes in upper-ocean structure. An interannual signal is also evident in NPSTMW volume and other characteristic properties with volume minima occurring in 1979, 1988, and 1999. This volume variability is correlated with the Pacific decadal oscillation (PDO) with zero time lag. Further analyses demonstrate the connection of NPSTMW to the basin-scale ocean circulation. With this, modulations of upper-ocean structure driven by the varying strength and position of the westerlies as well as the regional air–sea heat flux pattern are seen to contribute to the variability of NPSTMW volume on interannual time scales.Support for this research was provided by the Partnership for Advancing Interdisciplinary Modeling (PARADIGM), a National Ocean Partnership Program and by a NASA Modeling, Analysis, and the Prediction (MAP) project called Estimating the Circulation and Climate of the Ocean, Phase II (ECCO2)