Sustained Ocean Observations from Merchant Marine Vessels

2001 ◽  
Vol 35 (3) ◽  
pp. 38-42 ◽  
Author(s):  
Tom Rossby
Keyword(s):  
Upper Ocean ◽  
Atmospheric Conditions ◽  
Merchant Marine ◽  
Accurate Picture ◽  
Weather And Climate ◽  
The Mean ◽  
New Generation ◽  
Marine Vessels ◽  
Ocean Observations ◽  
Mean State

Merchant marine vessels have provided invaluable information about weather and climate over the seas. In this note, it is shown how these vessels also contribute to ocean research through systematic surveys of upper ocean temperature, salinity and currents. By repeatedly sampling a particular route, one can obtain an accurate picture of the mean state of the ocean and where and how it varies. With a few examples drawn from our own work we show how commercial shipping and cruise vessels, with their unparalleled access to the oceans, could give society far more extensive and valuable information about upper ocean and atmospheric conditions on a regular basis. But for this to happen, a new generation of ocean instrumentation needs to be developed that is optimized for completely automatic and unattended operation on such vessels. It also means working with the merchant marine community to develop guidelines and procedures for future cooperative efforts.

scholarly journals AXIS—An Autonomous Expendable Instrument System

2017 ◽  
Vol 34 (12) ◽  
pp. 2673-2682 ◽  
Author(s):  
D. M. Fratantoni ◽  
J. K. O’Brien ◽  
C. Flagg ◽  
T. Rossby
Keyword(s):  
Thermal Structure ◽  
New Technology ◽  
Space Time ◽  
Time Variability ◽  
Upper Ocean ◽  
Time Stamp ◽  
Merchant Marine ◽  
Marine Vessels ◽  
System Axis

AbstractExpendable bathythermographs (XBT) to profile upper-ocean temperatures from vessels in motion have been in use for some 50 years now. Developed originally for navy use, they were soon adapted by oceanographers to map out upper-ocean thermal structure and its space–-time variability from both research vessels and merchant marine vessels in regular traffic. These activities continue today. This paper describes a new technology—the Autonomous Expendable Instrument System (AXIS)—that has been developed to provide the capability to deploy XBT probes on a predefined schedule, or adaptively in response to specific events without the presence of an observer on board. AXIS is a completely self-contained system that can hold up to 12 expendable probes [XBTs, XCTDs, expendable sound velocimeter (XSV)] in any combination. A single-board Linux computer keeps track of what probes are available, takes commands from ashore via Iridium satellite on what deployment schedule to follow, and records and forwards the probe data immediately with a time stamp and the GPS position. This paper provides a brief overview of its operation, capabilities, and some examples of how it is improving coverage along two lines in the Atlantic.

Characteristics of the dynamical tropopause derived from satellite observations

2020 ◽  
Author(s):  
Yixuan Shou ◽  
Feng Lu ◽  
Shaowen Shou
Keyword(s):  
Geostationary Satellite ◽  
Tropopause Height ◽  
Reanalysis Dataset ◽  
Weather And Climate ◽  
Low Latitudes ◽  
Mean Pressure ◽  
Estimation Scheme ◽  
The Mean ◽  
Spatio Temporal ◽  
New Generation

<p><strong>                                                                                                                             Abstract</strong></p><p>As the products of the complicated interactions and the kinematic, chemical and radiative balances between upper troposphere and lower stratosphere, dynamical tropopause is recognized as a key boundary of atmosphere closely related to weather and climate change. In this study, a high-spatio-temporal-resolution dynamical tropopause pressure estimation scheme based on the measurements from the Advanced Geostationary Radiation Imager boarded on the new generation geostationary satellite of China, FengYun-4A, is proposed. The implemented retrieval model is quantitative validated against ERA-Interim reanalysis dataset showing a high accuracy with the correlation coefficient of 0.9603 and root-mean-square-error of 42.96 hPa. The method is applied to a 1-year period starting in January 2018 over the east hemisphere. The geographic distributions and the seasonal cycle show that the dynamical tropopause height is varied with the latitudes and seasons which has the mean pressure of about 50 hPa over low latitudes and about 300 hPa over the high latitudes where the tropopause height reaches the minimum during March-May. Generally, the folds preferentially occur in the subtropics around 20-40º latitude where the upper fronts located. They are found to have potential connection with the rain band splitting during the Mei-Yu season in East Asia.</p><p><strong>Keywords：</strong>Dynamic tropopause, FengYun-4 geostationary satellite, WV channels</p>

scholarly journals Instrumented Wave Gliders for Air-Sea Interaction and Upper Ocean Research

2021 ◽  
Vol 8 ◽  
Author(s):  
Laurent Grare ◽  
Nicholas M. Statom ◽  
Nick Pizzo ◽  
Luc Lenain
Keyword(s):  
State Of The Art ◽  
Data Sources ◽  
Upper Ocean ◽  
Independent Data ◽  
Minimal Flow ◽  
Structure Interaction ◽  
Weather And Climate ◽  
Frontal Processes ◽  
Ocean Observations ◽  
Measurement Capabilities

Over the last several years, the Air-Sea Interaction Laboratory at Scripps Institution of Oceanography has developed a fleet of wave-powered, uncrewed Wave Gliders (Liquid Robotics) specifically designed and instrumented for state-of-the-art air-sea interaction and upper ocean observations. In this study, measurement capabilities from these platforms are carefully described, compared, and validated against coincident measurements from well-established, independent data sources. Data collected from four major field programs from 2013 to 2020 are considered in the analysis. Case studies focusing on air-sea interaction, Langmuir circulations, and frontal processes are presented. We demonstrate here that these novel, instrumented platforms are capable of collecting observations with minimal flow-structure interaction in the air-sea boundary layer, a region of crucial current and future importance for models of weather and climate.

scholarly journals Impact of semidiurnal tidal variability during SSWs on the mean state of the ionosphere and thermosphere

2016 ◽  
Vol 121 (8) ◽  
pp. 8077-8088 ◽  
Author(s):  
N. M. Pedatella ◽  
A. D. Richmond ◽  
A. Maute ◽  
H.‐L. Liu
Keyword(s):  
The Mean ◽  
Tidal Variability ◽  
Mean State

scholarly journals Diurnal Coupling in the Tropical Oceans of CCSM3

2006 ◽  
Vol 19 (11) ◽  
pp. 2347-2365 ◽  
Author(s):  
Gokhan Danabasoglu ◽  
William G. Large ◽  
Joseph J. Tribbia ◽  
Peter R. Gent ◽  
Bruce P. Briegleb ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Diurnal Cycle ◽  
Upper Ocean ◽  
Solar Forcing ◽  
Layer Depth ◽  
Climate System Model ◽  
Tropical Oceans ◽  
Ocean Coupling ◽  
Coupling Interval ◽  
The Mean

Abstract New features that may affect the behavior of the upper ocean in the Community Climate System Model version 3 (CCSM3) are described. In particular, the addition of an idealized diurnal cycle of solar forcing where the daily mean solar radiation received in each daily coupling interval is distributed over 12 daylight hours is evaluated. The motivation for this simple diurnal cycle is to improve the behavior of the upper ocean, relative to the constant forcing over each day of previous CCSM versions. Both 1- and 3-h coupling intervals are also considered as possible alternatives that explicitly resolve the diurnal cycle of solar forcing. The most prominent and robust effects of all these diurnal cycles are found in the tropical oceans, especially in the Pacific. Here, the mean equatorial sea surface temperature (SST) is warmed by as much as 1°C, in better agreement with observations, and the mean boundary layer depth is reduced. Simple rectification of the diurnal cycle explains about half of the shallowing, but less than 0.1°C of the warming. The atmospheric response to prescribed warm SST anomalies of about 1°C displays a very different heat flux signature. The implication, yet to be verified, is that large-scale air–sea coupling is a prime mechanism for amplifying the rectified, daily averaged SST signals seen by the atmosphere. Although the use of upper-layer temperature for SST in CCSM3 underestimates the diurnal cycle of SST, many of the essential characteristics of diurnal cycling within the equatorial ocean are reproduced, including boundary layer depth, currents, and the parameterized vertical heat and momentum fluxes associated with deep-cycle turbulence. The conclusion is that the implementation of an idealized diurnal cycle of solar forcing may make more frequent ocean coupling and its computational complications unnecessary as improvements to the air–sea coupling in CCSM3 continue. A caveat here is that more frequent ocean coupling tends to reduce the long-term cooling trends typical of CCSM3 by heating already too warm ocean depths, but longer integrations are needed to determine robust features. A clear result is that the absence of diurnal solar forcing of the ocean has several undesirable consequences in CCSM3, including too large ENSO variability, much too cold Pacific equatorial SST, and no deep-cycle turbulence.

The Three-Cornered Hat Method for Estimating Error Variances of Three or More Atmospheric Data Sets – Part II: Evaluating Radio Occultation and Radiosonde Observations, Global Model Forecasts, and Reanalyses

2021 ◽  
Author(s):  
Therese Rieckh ◽  
Jeremiah P. Sjoberg ◽  
Richard A. Anthes
Keyword(s):  
Radio Occultation ◽  
State Of The Art ◽  
Specific Humidity ◽  
Data Sets ◽  
Error Growth ◽  
Atmospheric Conditions ◽  
Error Statistics ◽  
Weather And Climate ◽  
Atmospheric Data ◽  
The Impact

AbstractWe apply the three-cornered hat (3CH) method to estimate refractivity, bending angle, and specific humidity error variances for a number of data sets widely used in research and/or operations: radiosondes, radio occultation (COSMIC, COSMIC-2), NCEP global forecasts, and nine reanalyses. We use a large number and combinations of data sets to obtain insights into the impact of the error correlations among different data sets that affect 3CH estimates. Error correlations may be caused by actual correlations of errors, representativeness differences, or imperfect co-location of the data sets. We show that the 3CH method discriminates among the data sets and how error statistics of observations compare to state-of-the-art reanalyses and forecasts, as well as reanalyses that do not assimilate satellite data. We explore results for October and November 2006 and 2019 over different latitudinal regions and show error growth of the NCEP forecasts with time. Because of the importance of tropospheric water vapor to weather and climate, we compare error estimates of refractivity for dry and moist atmospheric conditions.

Comparison Of Drugs in Patients Using New Generation Anticoagulants

2021 ◽  
Vol 6 (14) ◽  
pp. 56-67
Author(s):  
Arslan Say ◽  
Abdülkadir ÇAKMAK ◽  
Gökhan KESKİN ◽  
Erdinç PELİT ◽  
Yılmaz ÖZBAY
Keyword(s):  
Atrial Fibrillation ◽  
Clinical Practice ◽  
Venous Thromboembolism ◽  
Oral Anticoagulants ◽  
Recurrent Venous Thromboembolism ◽  
Anticoagulant Drugs ◽  
History Of ◽  
The Mean ◽  
N 93 ◽  
New Generation

Aim: New generation anticoagulants rapidly find a wider area of use in the clinic due to the use problems of other oral anticoagulants. Anticoagulants such as Dabigatran, Rivaroxaban, and Apixaban with safer treatment intervals have been accepted in clinical practice guidelines and have taken their place as preferred drugs. In this study, we aimed to retrospectively examine the effects of three new-generation anticoagulant drugs on a group of patients. Material and Methods: In this retrospectively planned study, patients diagnosed with atrial fibrillation (n = 522) were divided into three groups according to the drugs used for treatment (Dabigatran, Rivaroxaban, and Apixaban). Routine blood values of the patients in each group were retrospectively scanned according to age, gender, time of drug initiation and presence of chronic disease. Results: According to the results obtained, it was found that the mean HCT, BUN, AST, ALT, MPV, Iron, and Ferritin were higher in patients using Apixaban than those using Dabigatran and Rivaroxaban drugs, but the age, average values of Hgb1 Hgb2, Hgb1, PLT, CrCl, Gfr and INR of the patients using Apixaban lower than those using Dabigatran and Rivaroxaban. The highest rate (22.5%) was found in the group of patients taking apixaban (n=93) when people taking the drugs were examined in terms of mortality. Conclusion: It has been observed that Rivaroxaban can be used more safely in patients with a history of acute cancer and thrombosis, patients with recurrent venous thromboembolism, and patients with high frailty, three drugs should be preferred instead of oral anticoagulants.

Interdecadal changes in the interannual variability of the summer temperature over Northeast Asia

2021 ◽  
pp. 1-50
Author(s):  
Ruidan Chen ◽  
Zhiping Wen ◽  
Riyu Lu ◽  
Wenjun Liu
Keyword(s):  
Interannual Variability ◽  
Northeast Asia ◽  
Tropical Indian Ocean ◽  
Summer Temperature ◽  
Atmospheric Variability ◽  
The Pacific ◽  
The Mean ◽  
Southeastern Tropical Indian Ocean ◽  
Interdecadal Changes ◽  
Mean State

AbstractThis study reveals the interdecadal changes in the interannual variability of the summer temperature over Northeast Asia (NEA), which presents an enhancement around the early 1990s and a reduction after the mid-2000s. The stronger NEA temperature variability after the early 1990s is favored by the enhanced influence of the Pacific–Japan (PJ) teleconnection, which is remotely modulated by the southeastern tropical Indian Ocean (SETIO). After the early 1990s, the mean state over the SETIO presents relatively warmer SST and ascending motion, favoring a good relationship between the local SST and convection. Therefore, the SETIO SST could prominently influence the local convection and subsequently modulate the convection over the western North Pacific (WNP) via a cross-equatorial overturning circulation. The abnormal convection over the WNP further triggers the PJ teleconnection to influence NEA. However, these ocean–atmosphere processes disappear before the early 1990s. In this period, the mean state over the SETIO features relatively colder SST and subsiding motion, accompanied by a poor relationship between the local SST and convection. Therefore, the variability of convection over the SETIO is weak, thus the atmospheric variability over the WNP is also weakened and the PJ teleconnection presents a different distribution that could not influence NEA. The reduced variability of NEA temperature after the mid-2000s is related to the feeble influence of the PJ teleconnection and the reduced variability of the SETIO SST, which is modulated by the SST over the tropical central–eastern Pacific during the preceding winter to spring.

scholarly journals Impact of Resolution on the Tropical Pacific Circulation in a Matrix of Coupled Models

2009 ◽  
Vol 22 (10) ◽  
pp. 2541-2556 ◽  
Author(s):  
Malcolm J. Roberts ◽  
A. Clayton ◽  
M.-E. Demory ◽  
J. Donners ◽  
P. L. Vidale ◽  
...  
Keyword(s):  
Coupled Model ◽  
Walker Circulation ◽  
Ocean Model ◽  
Tropical Pacific ◽  
Coupled Models ◽  
Model Stability ◽  
The Mean ◽  
The Impact ◽  
Mean State ◽  
The Tropical Pacific

Abstract Results are presented from a matrix of coupled model integrations, using atmosphere resolutions of 135 and 90 km, and ocean resolutions of 1° and 1/3°, to study the impact of resolution on simulated climate. The mean state of the tropical Pacific is found to be improved in the models with a higher ocean resolution. Such an improved mean state arises from the development of tropical instability waves, which are poorly resolved at low resolution; these waves reduce the equatorial cold tongue bias. The improved ocean state also allows for a better simulation of the atmospheric Walker circulation. Several sensitivity studies have been performed to further understand the processes involved in the different component models. Significantly decreasing the horizontal momentum dissipation in the coupled model with the lower-resolution ocean has benefits for the mean tropical Pacific climate, but decreases model stability. Increasing the momentum dissipation in the coupled model with the higher-resolution ocean degrades the simulation toward that of the lower-resolution ocean. These results suggest that enhanced ocean model resolution can have important benefits for the climatology of both the atmosphere and ocean components of the coupled model, and that some of these benefits may be achievable at lower ocean resolution, if the model formulation allows.

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