scholarly journals Annual variation in the foraging behaviour of thick-billed murres in relation to upper-ocean thermal structure around St. George Island, Bering Sea

2010 ◽  
Vol 8 ◽  
pp. 289-298 ◽  
Author(s):  
N Kokubun ◽  
A Takahashi ◽  
M Ito ◽  
K Matsumoto ◽  
AS Kitaysky ◽  
...  
Keyword(s):  
Bering Sea ◽  
Annual Variation ◽  
Foraging Behaviour ◽  
Thermal Structure ◽  
Upper Ocean

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.

scholarly journals Inorganic Radiocarbon in Time-Series Sediment Trap Samples: Implication of Seasonal Variation of 14C in the Upper Ocean

Radiocarbon ◽  
1996 ◽  
Vol 38 (3) ◽  
pp. 583-595 ◽  
Author(s):  
Makio C. Honda
Keyword(s):  
Time Series ◽  
Bering Sea ◽  
Sediment Trap ◽  
Seasonal Variability ◽  
Sea Of Okhotsk ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Sediment Traps ◽  
Upper Ocean ◽  
The Bering Sea

In order to verify sediment trap samples as indicators of upper ocean 14C concentrations, particulate inorganic radiocarbon (PICΔ14C) collected by time-series sediment traps in the Sea of Okhotsk and the Bering Sea was measured by accelerator mass spectrometry (AMS). All of the PICΔ14C measurements were < 0‰, in contrast to GEOSECS 14C data in the upper ocean from the northwestern North Pacific. This difference is attributed to the upwelling of deepwater that contains low Δ14C of dissolved inorganic carbon (DICΔ14C) and to the decrease over time of surface DICΔ14C owing to the decrease of atmospheric Δ14C values. In addition, PICΔ14C values showed significant seasonal variability: PICΔ14C collected in the fall was the greatest (-22‰ on average), whereas PICΔ14C collected in winter showed an average minimum of −48‰. It is likely that this difference was caused by changes in mixed layer thickness. Although some uncertainties remain, further study on PICΔ14C will enable us to estimate seasonal variability in DICΔ14C and air-sea CO2 exchange rate.

Recent interannual upper ocean variability in the deep southeastern Bering Sea

2005 ◽  
Vol 63 (2) ◽  
pp. 381-405 ◽  
Author(s):  
Amy E. Wirts ◽  
Gregory C. Johnson
Keyword(s):  
Bering Sea ◽  
Upper Ocean ◽  
Ocean Variability

scholarly journals Upper-Ocean Thermal Structure and the Western North Pacific Category 5 Typhoons. Part II: Dependence on Translation Speed

2009 ◽  
Vol 137 (11) ◽  
pp. 3744-3757 ◽  
Author(s):  
I-I. Lin ◽  
Iam-Fei Pun ◽  
Chun-Chieh Wu
Keyword(s):  
Mixed Layer ◽  
North Pacific ◽  
Western North Pacific ◽  
Thermal Structure ◽  
Subsurface Layer ◽  
Heat Content ◽  
Correlation Coefficients ◽  
Upper Ocean ◽  
Translation Speed

Abstract Using new in situ ocean subsurface observations from the Argo floats, best-track typhoon data from the U.S. Joint Typhoon Warning Center, an ocean mixed layer model, and other supporting datasets, this work systematically explores the interrelationships between translation speed, the ocean’s subsurface condition [characterized by the depth of the 26°C isotherm (D26) and upper-ocean heat content (UOHC)], a cyclone’s self-induced ocean cooling negative feedback, and air–sea enthalpy fluxes for the intensification of the western North Pacific category 5 typhoons. Based on a 10-yr analysis, it is found that for intensification to category 5, in addition to the warm sea surface temperature generally around 29°C, the required subsurface D26 and UOHC depend greatly on a cyclone’s translation speed. It is observed that even over a relatively shallow subsurface warm layer of D26 ∼ 60–70 m and UOHC ∼ 65–70 kJ cm−2, it is still possible to have a sufficient enthalpy flux to intensify the storm to category 5, provided that the storm can be fast moving (typically Uh ∼ 7–8 m s−1). On the contrary, a much deeper subsurface layer is needed for slow-moving typhoons. For example at Uh ∼ 2–3 m s−1, D26 and UOHC are typically ∼115–140 m and ∼115–125 kJ cm−2, respectively. A new concept named the affordable minimum translation speed Uh_min is proposed. This is the minimum required speed a storm needs to travel for its intensification to category 5, given the observed D26 and UOHC. Using more than 3000 Argo in situ profiles, a series of mixed layer numerical experiments are conducted to quantify the relationship between D26, UOHC, and Uh_min. Clear negative linear relationships with correlation coefficients R = −0.87 (−0.71) are obtained as Uh_min = −0.065 × D26 + 11.1, and Uh_min = −0.05 × UOHC + 9.4, respectively. These relationships can thus be used as a guide to predict the minimum speed a storm has to travel at for intensification to category 5, given the observed D26 and UOHC.

scholarly journals Reconstructing the thermal structure of the upper ocean: Insights from planktic foraminifera shell chemistry and alkenones in modern sediments of the tropical eastern Indian Ocean

2011 ◽  
Vol 26 (3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Mahyar Mohtadi ◽  
Delia W. Oppo ◽  
Andreas Lückge ◽  
Ricardo DePol-Holz ◽  
Stephan Steinke ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Thermal Structure ◽  
Eastern Indian Ocean ◽  
Upper Ocean ◽  
Planktic Foraminifera ◽  
Shell Chemistry
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