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Samuel R. Laney

given sensor or instrument is polled, configured, or driven within a larger observing network. The challenges that this increased sophistication in sensors and instruments adds to typical integration scenarios may be relatively minor in large-scale observational programs that enjoy substantial technical support. Yet for individual researchers or smaller groups that lack access to appropriate instrumentation expertise, this increased sophistication can impact and in some cases may limit the types of

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Claudia Lorrai, Daniel F. McGinnis, Peter Berg, Andreas Brand, and Alfred Wüest

the sediment roughness and water depth, the measurement height above the sediment (in our case between 10 and 15 cm), determines the horizontal footprint, which is defined as the area that contributes (e.g., 90%) to the flux ( Berg et al. 2007 ). 3. Implementation of EC measurements and data analysis a. Instrumentation: The realization of an EC device The EC device includes a Clark-type microelectrode oxygen sensor (Unisense AS, Denmark) and an acoustic Doppler velocimeter (ADV; “Vector

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G. Reverdin, J. Boutin, N. Martin, A. Lourenco, P. Bouruet-Aubertot, A. Lavin, J. Mader, P. Blouch, J. Rolland, F. Gaillard, and P. Lazure

drifters has been carried during that period primarily by four different manufacturers (Clearwater Instrumentations, Metocean Data Systems, Pacific Gyre, and Technocean). The common drifter design consists of a surface float of nearly 40-cm diameter connected with a tether to a drogue, often a 7-m-long holey sock attached to it 12 m below the surface (there is a smaller alternative model with 32-cm-diameter surface float, but not considered here). Temperature measurement is done by a thermistor potted

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Hans van Haren, Martin Laan, Sander Asjes, and Bas Denissen

1. Introduction Ocean researchers who regularly deploy stand-alone subsurface instrumentation in the deep sea may have experienced difficulties in retrieving their precious scientific materials and archived data. Normally, such instrumented lines or landers are equipped with one or two devices to release one or more “anchor” weights acoustically from a deck unit on board a ship. In some occasions when the anchor weight has to be retrieved, a pop-up buoy is released instead of the entire

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Marshall Swartz, Daniel J. Torres, Steve Liberatore, and Robert Millard

1. Background Since the first use of conducting wire to telemeter data from instruments lowered from ships, users have faced significant constraints in both data speed and maximum achievable distance. Seemingly a technology plateau was reached, because for over three decades, various telemetry schemes achieved less than 10 kbit s −1 data rates over 10-km-long single- or three-conductor cables developed for oil drilling instrumentation and control applications. In the United States, the

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Keith Jackson, Jeremy Wilkinson, Ted Maksym, David Meldrum, Justin Beckers, Christian Haas, and David Mackenzie

1. Introduction This paper describes the development of a new ice mass balance (IMB) buoy that uses the established principle of measuring temperatures at closely spaced intervals down a chain of sensors deployed through sea ice. However, this new IMB buoy uses a novel construction method for the chain that allows opportunities for dramatic reduction in cost and complexity compared to previous thermistor chain designs. Also, we describe a heated anemometer mode that allows for identification of

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Samuel Harding, Levi Kilcher, and Jim Thomson

rates ( Moum and Nash 2009 ; Perlin and Moum 2012 ). In this process, the motion of the submerged instrumentation platforms can be measured using a combination of acceleration, angular rotation rate, compass, and pressure sensor data. Integrated multiaxis inertial measurement units (IMUs) are available to detect both the linear acceleration and the angular rotation rate in pitch, roll, and yaw. One application of tidal current research of increasing interest is in the harnessing of energetic flows

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Erik O. Nilsson, Anna Rutgersson, and Peter P. Sullivan

1. Introduction The eddy correlation method is a standard method to determine turbulent scalar fluxes. The method uses correlation of the high-frequency signal of the vertical velocity and the scalar of interest. If the two signals are measured by separate instruments (which is the case for many scalars), the sensors must be separated to avoid flow distortion. This displacement unfortunately attenuates the flux estimate. The loss of flux occurs because of an unavoidable decorrelation between

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Satoshi Sakai, Aya Ito, Kazuhiro Umetani, Isao Iizawa, and Masanori Onishi

.0 W m −2 for overcast skies. From these values, we can expect that the error in the calculated irradiance due to an error in the zenith angle is less than 1 W m −2 deg −1 . 3. Instrumentation The present instrument is shown schematically in Fig. 2a and a prototype is depicted in Fig. 2b . The device consists of a thermopile sensor with IR lens, a thermistor, and an operational amplifier. The thermopile sensor type is 15TP551N (SEMITEC Ishizuka Electronics) in a TO5 (metal can) package. A cut

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A. T. Jessup and R. Branch

1. Introduction Validation of sea surface temperature (SST) measurements derived from satellite-based infrared sensors is complicated because the representative depth of the satellite measurements is significantly different from the depth of in situ measurements used for validation. Infrared (IR) techniques have an effective measurement depth of less than 10 μ m and provide the surface “skin” temperature T skin . The most common in situ SST validation measurements use the bulk temperature T

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