Assessment of the Upper-Ocean Observing System in the Equatorial Pacific: The Role of Argo in Resolving Intraseasonal to Interannual Variability

2015 ◽  
Vol 32 (9) ◽  
pp. 1668-1688 ◽  
Author(s):  
Florent Gasparin ◽  
Dean Roemmich ◽  
John Gilson ◽  
Bruce Cornuelle
Keyword(s):  
Large Scale ◽  
Equatorial Pacific ◽  
Optimal Interpolation ◽  
Upper Ocean ◽  
Spatial Covariance ◽  
The Pacific ◽  
Independent Observations ◽  
The Time Domain ◽  
Ocean Observing

AbstractUsing more than 10 years of Argo temperature and salinity profiles (2004–14), a new optimal interpolation (OI) of the upper ocean in the equatorial Pacific is presented. Following Roemmich and Gilson’s procedures, which were formulated for describing monthly large-scale anomalies, here every 5 days anomaly fields are constructed with improvements in the OI spatial covariance function and by including the time domain. The comparison of Argo maps with independent observations, from the TAO/TRITON array, and with satellite sea surface height (SSH), demonstrates that Argo is able to represent around 70%–80% of the variance at intraseasonal time scales (periods of 20–100 days) and more than 90% of the variance for the seasonal-to-longer-term variability. The RMS difference between Argo and TAO/TRITON temperatures is lower than 1°C and is around 1.5 cm when the Argo steric height is compared to SSH. This study also assesses the efficacy of different observing system components and combinations, such as SSH, TAO/TRITON, and Argo, for estimating subsurface temperature. Salinity investigations demonstrate its critical importance for density near the surface in the western Pacific. Objective error estimates from the OI are used to evaluate different sampling strategies, such as the recent deployment of 41 Argo floats along the Pacific equator. Argo’s high spatial resolution compared with that of the moored array makes it better suited for studying spatial patterns of variability and propagation on intraseasonal and longer periods, but it is less well suited for studying variability on periods shorter than 20 days at point locations. This work is a step toward better utilization of existing datasets, including Argo, and toward redesigning the Tropical Pacific Observing System.

scholarly journals Pacific subduction control on Asian continental deformation including Tibetan extension and eastward extrusion tectonics

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
W. P. Schellart ◽  
Z. Chen ◽  
V. Strak ◽  
J. C. Duarte ◽  
F. M. Rosas
Keyword(s):  
Subduction Zones ◽  
Large Scale ◽  
Active Role ◽  
The Pacific ◽  
Slab Rollback ◽  
Continental Deformation ◽  
Basin Formation ◽  
Backarc Basins ◽  
East West

Abstract The India-Asia collision has formed the highest mountains on Earth and is thought to account for extensive intraplate deformation in Asia. The prevailing explanation considers the role of the Pacific and Sunda subduction zones as passive during deformation. Here we test the hypothesis that subduction played an active role and present geodynamic experiments of continental deformation that model Indian indentation and active subduction rollback. We show that the synchronous activity and interaction of the collision zone and subduction zones explain Asian deformation, and demonstrate that east-west extension in Tibet, eastward continental extrusion and Asian backarc basin formation are controlled by large-scale Pacific and Sunda slab rollback. The models require 1740 ± 300 km of Indian indentation such that backarc basins form and central East Asian extension conforms estimates. Indentation and rollback produce ~260–360 km of eastward extrusion and large-scale clockwise upper mantle circulation from Tibet towards East Asia and back to India.

Extreme nonhydrostatic tidal dynamics

2019 ◽  
pp. 37-51
Author(s):  
Наум Евсеевич Вольцингер ◽  
Алексей Анатольевич Андросов
Keyword(s):  
Boundary Value Problem ◽  
Large Scale ◽  
Water Exchange ◽  
Dynamic Pressure ◽  
Boundary Value ◽  
Vertical Motion ◽  
Vertical Acceleration ◽  
Tidal Dynamics ◽  
The Pacific

Моделирование длинноволновых океанологических процессов традиционно выполняется в гидростатическом (Гс) приближении, обеспечивающем высокую точность расчета гидрофизических полей, когда вертикальным ускорением движения можно пренебречь. На горном рельефе это не так, и учет динамической компоненты давления становится необходимым. Негидростатическое (Нг) моделирование крупномасштабных океанологических явлений реализуется решением 3D краевой гидродинамической задачи. Структуру метода составляют этапы решения Гс-задачи, краевой задачи для уравнения Пуассона (Нг) и коррекции полей гидрофизических характеристик. Значимость Нг-фактора выявляется при рассмотрении безразмерного вида уравнений, когда безразмерные параметры характеризуют горный рельеф области. Случай резких изменений рельефа, требующий решения Нг-задачи, - пролив Ломбок. Приводятся оценки Нг-фактора в водообмене между океанами, результаты сравнения спектров вертикальной скорости в Гс- и Нг-постановках. Modelling of long-wave oceanological processes is traditionally performed in a hydrostatic (Hs) approximation, which ensures high accuracy of the calculation of hydrophysical fields, when the vertical acceleration of vertical motion can be neglected. In mountainous terrain, this is not the case, and consideration of the dynamic pressure component becomes necessary. Non-hydrostatic (Nh) modelling of large-scale oceanological phenomena is implemented by solving hydrodynamic boundary value problem in an arbitrary 3D domain. The structure of the method consists of the stages of solving the Hs problem, the boundary value problem for the Poisson equation (Nh), and the correction of the fields of hydrophysical characteristics. That is the pressure is presented as a sum of its hydrostatic and dynamical components. Significance of Nh is revealed when considering the dimensionless type of equations, when dimensionless parameters characterize the mountain relief of the region. The Lombok Strait having a complex morphometric structure is an important link in the water exchange between the Pacific and Indian Oceans, it has been chosen as the object for modelling. Estimates of the role of Nh in water exchange between the oceans are given using the comparison of the solution for problems in Hs and Nh sets. It indicates the need to take into account Nh in conditions of pronounced sea mountain relief.

scholarly journals Oceanic origins for wintertime Euro-Atlantic blocking

2020 ◽  
Author(s):  
Ayako Yamamoto ◽  
Masami Nonaka ◽  
Patrick Martineau ◽  
Akira Yamazaki ◽  
Young-Oh Kwon ◽  
...  
Keyword(s):  
Large Scale ◽  
Dispersion Model ◽  
Reanalysis Data ◽  
Low Latitude ◽  
The Pacific ◽  
Atlantic Origin ◽  
Lagrangian Dispersion ◽  
Low Altitude ◽  
Heat And Moisture

Abstract. Although conventionally attributed to dry dynamics, increasing evidence points to a key role of moist dynamics in the formation and maintenance of blocking events. The source of moisture crucial for these processes, however, remains elusive. In this study, we identify the moisture sources responsible for latent heating associated with the wintertime Euro-Atlantic blocking events detected over 31 years (1979–2010). To this end, we track atmospheric particles backward in time from the blocking centres for a period of 10 days, using an offline Lagrangian dispersion model applied to an atmospheric reanalysis data. The analysis reveals that 36–55 % of particles gain a massive amount of heat and moisture from the ocean over the course of 10 days. Via large-scale ascent, these moist particles transport low potential vorticity (PV) air of low-altitude, low-latitude origins to the upper troposphere where the amplitude of blocking is the most prominent, consistent with the previous studies. PV of these moist particles remains significantly lower compared to their dry counterparts throughout the course of 10 days, preferentially constituting blocking cores. Further analysis reveals that approximately two-thirds of the moist particles source their moisture locally from the Atlantic, while the remaining one-third from the Pacific. The Gulf Stream and Kuroshio and their extensions, as well as the eastern Pacific northeast of Hawaii, not only provide heat and moisture to the particles but also act as springboards for their large-scale, cross-isentropic ascent. While the particles of the Atlantic origin swiftly ascend just before their arrival at the blocking, those of the Pacific origin ascend additional few days earlier, after which they carry low PV in the same manner as dry particles. Thus, our study reveals that what may appear to be a blocking maintenance mechanism governed by dry dynamics alone can, in fact, be of moist origin.

The Role of Sense of Direction and Other Factors During Navigation in a Large-Scale, Unconstrained Environment

2013 ◽  
Author(s):  
Elisabeth J. Ploran ◽  
Ericka Rovira ◽  
James C. Thompson ◽  
Raja Parasuraman
Keyword(s):  
Large Scale ◽  
Sense Of Direction

The Role Of Surface Waves On The Upper Ocean: Application In Indonesian Seas

Jurnal Segara ◽  
2012 ◽  
Vol 8 (1) ◽  
pp. 1 ◽  
Author(s):  
Rita Tisiana Dwi Kuswardani ◽  
Fangli Qiao
Keyword(s):  
Surface Waves ◽  
Upper Ocean ◽  
Indonesian Seas

Magnetic Properties of xCeO2•(50 − x) PbO•50B2O3 Glasses and Glass Ceramics

2017 ◽  
Vol 13 (1) ◽  
pp. 4486-4494 ◽  
Author(s):  
G.El Damrawi ◽  
F. Gharghar
Keyword(s):  
Magnetic Properties ◽  
Large Scale ◽  
Glass Ceramics ◽  
Magnetic Behavior ◽  
Crystal Formation ◽  
Dual Roles ◽  
Effective Agent ◽  
Ordered Structures ◽  
Essential Change

Cerium oxide in borate glasses of composition xCeO2·(50 − x)PbO·50B2O3 plays an important role in changing both microstructure and magnetic behaviors of the system. The structural role of CeO2 as an effective agent for cluster and crystal formation in borate network is clearly evidenced by XRD technique. Both structure and size of well-formed cerium separated clusters have an effective influence on the structural properties. The cluster aggregations are documented to be found in different range ordered structures, intermediate and long range orders are the most structures in which cerium phases are involved. The nano-sized crystallized cerium species in lead borate phase are evidenced to have magnetic behavior.  The criteria of building new specific borate phase enriched with cerium as ferrimagnetism has been found to keep the magnetization in large scale even at extremely high temperature. Treating the glass thermally or exposing it to an effective dose of ionized radiation is evidenced to have an essential change in magnetic properties. Thermal heat treatment for some of investigated materials is observed to play dual roles in the glass matrix. It can not only enhance alignment processes of the magnetic moment but also increases the capacity of the crystallite species in the magnetic phases. On the other hand, reverse processes are remarked under the effect of irradiation. The magnetization was found to be lowered, since several types of the trap centers which are regarded as defective states can be produced by effect of ionized radiation. 

The Impact of Quantitative Easing on Emerging Markets – Literature Review

e-Finanse ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 67-76
Author(s):  
Piotr Bartkiewicz
Keyword(s):  
Emerging Markets ◽  
Large Scale ◽  
Empirical Literature ◽  
Quantitative Easing ◽  
Methodological Choices ◽  
The Subject ◽  
Methodological Approaches ◽  
The Impact ◽  
Sufficient Precision

AbstractThe article presents the results of the review of the empirical literature regarding the impact of quantitative easing (QE) on emerging markets (EMs). The subject is of interest to policymakers and researchers due to the increasingly larger role of EMs in the world economy and the large-scale capital flows occurring after 2009. The review is conducted in a systematic manner and takes into consideration different methodological choices, samples and measurement issues. The paper puts the summarized results in the context of transmission channels identified in the literature. There are few distinct methodological approaches present in the literature. While there is a consensus regarding the direction of the impact of QE on EMs, its size and durability have not yet been assessed with sufficient precision. In addition, there are clear gaps in the empirical findings, not least related to relative underrepresentation of the CEE region (in particular, Poland).

Age Advantages of Emotional Experience during the COVID-19 Pandemic are Robust, but Diminished Compared to Pre-pandemic Conditions

2020 ◽  
Author(s):  
Rui Sun ◽  
Disa Sauter
Keyword(s):  
Older Adults ◽  
Large Scale ◽  
Negative Emotion ◽  
Emotional Experience ◽  
Negative Emotions ◽  
Older Individuals ◽  
Selection Strategies ◽  
Scale Test ◽  
Prolonged Stress

Getting old is generally seen as unappealing, yet aging confers considerable advantages in several psychological domains (North & Fiske, 2015). In particular, older adults are better off emotionally than younger adults, with aging associated with the so-called “age advantages,” that is, more positive and less negative emotional experiences (Carstensen et al., 2011). Although the age advantages are well established, it is less clear whether they occur under conditions of prolonged stress. In a recent study, Carstensen et al (2020) demonstrated that the age advantages persist during the COVID-19 pandemic, suggesting that older adults are able to utilise cognitive and behavioural strategies to ameliorate even sustained stress. Here, we build on Carstensen and colleagues’ work with two studies. In Study 1, we provide a large-scale test of the robustness of Carstensen and colleagues’ finding that older individuals experience more positive and less negative emotions during the COVID-19 pandemic. We measured positive and negative emotions along with age information in 23,629 participants in 63 countries in April-May 2020. In Study 2, we provide a comparison of the age advantages using representative samples collected before and during the COVID-19 pandemic. We demonstrate that older people experience less negative emotion than younger people during the prolonged stress of the COVID-19 pandemic. However, the advantage of older adults was diminished during the pandemic, pointing to a likely role of older adults use of situation selection strategies (Charles, 2010).

An Ocean Observing System for Large-Scale Monitoring and Mapping of Noise Throughout the Stellwagen Bank National Marine Sanctuary

2011 ◽  
Author(s):  
Christopher W. Clark ◽  
William T. Ellison ◽  
Leila T. Hatch ◽  
Richard L. Merrick ◽  
Sofie M. Van Parijs ◽  
...  
Keyword(s):  
Large Scale ◽  
Ocean Observing
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