RRS Discovery Cruise 368, 15 Jul - 04 Aug 2011. Hydrographic measurements on WOCE line A16N

RRS Discovery Cruise 368 was a repeat occupation of part of the Atlantic hydrographic section designated by the World Ocean Circulation Experiment (WOCE) as A16N. A total of 29 CTDO (conductivity-temperature-depth-oxygen) stations were occupied. This included one test station, 27 stations between 49N and 23N on the WOCE A16N ‘20W’ line, and one final station near the ESTOC site close to Tenerife. Continuous profile measurements were CTDO and Lowered Acoustic Doppler Current Profiler (LADCP). Discrete bottle measurements from a 24-place rosette included salinity and dissolved oxygen analysed on board, and dissolved inorganic nutrients, Dissolved Inorganic Carbon and Total Alkalinity for analysis ashore. Underway measurements included Vessel-Mounted ADCP, surface ocean measurements and surface meteorology. The cruise was a UK contribution to the GO-SHIP sustained hydrography program. It was a partial repeat of the line designated in WOCE as A16N, which was previously occupied as a comprehensive cruise in 2003. In addition, a microbial program was carried out as an opportunistic activity by scientists who would remain on board for the following cruise.This report describes the methods used to acquire and process the data on board the ship during RRS Discovery Cruise 368.<br/

RSS James Cook Cruise JC032, 07 Mar – 21 Apr 2009. Hydrographic sections across the Brazil Current and at 24°S in the Atlantic.

Hydrographic sections were occupied in the South Atlantic Ocean and during March - April 2009 aboard the RRS James Cook (JC032). Three of these sections intersected the Brazil current at three separate latitudes during the steam northwards from Montevideo. The main trans-Atlantic section was occupied at 24°S. The primary objective of this cruise was to measure ocean physical, chemical and biological parameters in order to establish regional budgets of heat freshwater and carbon. The main section completed an overall aim, devised under the Oceans 2025 project, to create a box around the South Atlantic and Southern Ocean region to expose the regional circulation scheme and basin-scale budgets of physical and biogeochemical properties by performing a box-inverse analysis of the new observations. A total of 118 CTD/LADCP stations were sampled across the South Atlantic. In addition to temperature, salinity and oxygen profiles from the sensors on the CTD package, water samples from a 24-bottle rosette were analysed for salinity, dissolved oxygen and inorganic nutrients at each station. Water samples were collected from strategically selected stations and analysed onboard ship for SF6, CFC’s, pCO2, TIC, alkalinity, and nutrient biogeochemistry. In addition, samples were collected from the ship’s underway system to calibrate and compliment the data continually collected by the TSG (thermosalinograph). Full depth velocity measurements were made at every station by an LADCP (Lowered Acoustic Doppler Current Profiler) mounted on the frame of the rosette. Throughout the cruise, velocity data in the upper few hundred metres of the water column were collected by the ship’s VMADCP (vessel mounted acoustic Doppler current profiler) transducers (75Hz and 150Hz) mounted on the hull. Meteorological variables were monitored using the onboard surface water and meteorological sampling system (SURFMET). Bathymetric data was collected using the EA600 echo sounder and EM120 swath system, which is attached to the hull. This report describes the methods used to acquire and process the data aboard the ship during cruise JC032

RRS James Clark Ross Cruise JR306, 10-20 Jan 2015. Hydrographic measurements on WOCE line SR1b

Twentieth complete occupation of the Drake Passage section, established during the World Ocean Circulation Experiment as repeat section SR1b, first occupied in 1993 and re occupied most years since then. Full-depth temperature, salinity, and lowered ADCP velocity profiles were measured at the 30 repeat stations (with the 9 northern stations along 58 W, as from 2009 on). Underway measurements included navigation, VM-ADCP, sea surface temperature and salinity, water depth, and meteorological variables. The objectives were to investigate interannual variability in Antarctic Circumpolar Current (ACC) structure and Transport, the positions of the ACC fronts, and Drake Passage temperature and salinity distributions

Assessing the Presence and Distribution of 23 Hawaiian Yellow-Faced Bee Species on Lands Adjacent to Military Installations on O‘ahu and Hawai‘i Island

Reports were scanned in black and white at a resolution of 600 dots per inch and were converted to text using Adobe Paper Capture Plug-in.The endemic Hylaeus bees are critical pollinators in native ecosystems in Hawai‘i. Seven species are proposed for listing as endangered, and many more are rare and potentially endangered. We surveyed 40 localities on O‘ahu, 56 on Hawai‘i, and approximately 70 km of the coastline of Hawai‘i for 23 species of native Hylaeus, including four added during the course of the project. All of the native Hylaeus were much rarer than they were during previous surveys in 1999–2002, including many previously considered common. The only target species found in significant numbers was H. anthracinus, which is restricted to narrow strips of seashore vegetation on both islands but can occur in high density where present. However, the largest O‘ahu population, at Ka‘ena Point, appears to have completely disappeared since it was last observed in 2002. Significant populations exist on Hawai‘i, but only two sites are currently known on O‘ahu. Six of the other species on O‘ahu were not seen at all, and the remaining six (H. anomalus, H. laetus, H. makaha, H. mamo, H. mana, and H. mimicus) were collected once or twice and/or with a total of 1–5 individuals each. On Hawai‘i, only H. flavipes, H. kona, H. laetus, H. ombrias, and H. rugulosus were collected, mainly from in or around Pōhakuloa Training Area during a brief period of July and August. Most non-target species have been found at least once, but nearly all in low numbers; some of the less common ones, including H. setosifrons on Hawai‘i, were extremely rare or absent. The past several years have been extremely dry on the leeward sides of the islands, where most of the rare species occur, and drought may be a factor in the low numbers of bees. Serious damage and mortality among Myoporum sandwicense, an important floral resource, as a result of thrips infestation may also be important in reducing numbers and diversity of bees in montane areas of Hawai‘i. These results indicate that management of Hylaeus for recovery will be difficult, particularly at montane sites, but that the conservation need is also increasingly urgent as invasive species and climate change are having a greater and more rapid impact than anticipated. In coastal sites, the alien tree Heliotropium foertherianum (=Tournefortia argentea, tree heliotrope) is a critical floral resource for Hylaeus and should be managed with careful regard for impacts on bee populations.This project was funded by Department of Defense Legacy Resource Management Program grant 11-104 to the Hawai‘i Division of Forestry and Wildlife. We thank Betsy Gagné, Lisa Hadway, Ryan Peralta, and Elliott Parsons of DOFAW; Peter Peshut, Nikhil Inman-Narahari, Rogelio Doratt, Rachel Moseley, Martha Kawasaki, and Bridget Frederick of Pōhakuloa Training Area; Kapua Kawelo, Joby Rohrer, Michael Walker, Stephanie Joe, and many others of the O‘ahu Army Natural Resources Program; Sam Droege of USGS; Jason Gibbs of Cornell University; and Donald Price, Leon Hallacher, and Herbert Poepoe of the University of Hawai‘i–Hilo for support and assistance in carrying out work for this project

RRS James Clark Ross Cruise 302, 06 Jun - 21 Jul 2014. The 2015 RAGNARRoC, OSNAP AND Extended Ellett Line cruise report

Cruise JR302 was an NERC-NC funded cruise aiming to complete a full CTD section across the subpolar gyre, from Canada to Greenland to Scotland. The CTD section was located along the OSNAP track (www.ukosnap.org), providing a high quality and high resolution synoptic survey for the start of that programme. The objectives included a full suite of biogeochemistry measurements under the RAGNARRoC programmes. Finally, the eastern part of the section included the 2014 occupation of the Extended Ellett Line (projects.noc.ac.uk/ExtendedEllettLine) between Scotland and Iceland. Additional sections were made around the Cape Farewell region with the objective of measuring transport and the movement of water away from the boundary currents. Additional objectives included deploying eight Met Office Argo floats, and recovering one SAMS glider. Two new instruments were trialled by deploying them on the CTD frame; the IMP and RBR. All objectives were successfully completed

Observational advances in estimates of oceanic heating

Since the early twenty-first century, improvements in understanding climate variability resulted from the growth of the ocean observing system. The potential for a closure of the Earth’s energy budget has emerged with the unprecedented coverage of Argo profiling floats, which now provide a decade (2006–2015) of invaluable information on ocean heat content changes above 2000 m. The expertise gained from Argo and repeat hydrography sections motivated the extension of the array toward the ocean bottom, which will progressively reveal the poorly known deep ocean and reduce the uncertainty of its presumed 10–15 % contribution to the global ocean warming trend of 0.65–0.80 W m−2. The sustainability and synergy of various observing systems helped to corroborate numerical models and decipher the internal variability of distinct ocean basins. Due to unique observations of the circulation in the North Atlantic, particular attention is paid to heat content changes and their relationship to dynamic variability in that region

A crop water stress index based internet of things decision support system for precision irrigation of wine grape

The goal of irrigation for wine grape grown in arid or semiarid regions is to sustain vine survival and to optimize berry attributes for quality wine production. Precision irrigation of wine grape is hindered by the lack of a smart, decision support system (DSS) to remotely monitor vine water status. The objectives of this study were to: develop and field test an Internet of Things (IoT) DSS system for precision irrigation of wine grape. The IoT system was comprised of a suite of insitu sensors used to monitor real-time weather conditions, grapevine canopy temperature, soil moisture, and irrigation amount. Sensor data were collected and stored on a field deployed data logger that calculated a daily thermal Crop Water Stress Index (CWSI) for grapevine using a neural network model with real-time sensor data model inputs. The data logger also hosted, via a cellular modem, webpages showing a running, 12-day history of daily CWSI, fraction of available soil moisture (fASW), irrigation amount, and other sensor data. The webpages were accessible to vineyard managers via cell phone or computer. The CWSI based IoT DDS system was installed at two small acreage, commercial estate vineyards in southwestern Idaho USA over four growing seasons. At each vineyard site, the DSS was used daily by the vineyard irrigation manager to schedule irrigation events. Neither vineyard manager used any other quantitative vine water status monitoring tool for irrigation management decisions. The midday leaf water potential (LWP) of grapevines was routinely measured by research project personnel. Data collected over the study period at each vineyard showed a significant (p < 0.001) correlation with LWP and fASW, providing evidence that, under the conditions of this study, the daily CWSI based IoT provided automated, remote monitoring of vine water status. Both vineyard managers reported daily use of the DSS for irrigation scheduling decisions. Over the four-year study, each vineyard manager was able to maintain consistent seasonal average CWSI daily values and irrigation application amounts, despite yearly differences in climatic conditions. The results of this study demonstrate that a CWSI based IoT DSS can be used for precision irrigation of wine grape in a commercial vineyard under semiarid growing conditions

Moving spray-plate center-pivot sprinkler rating index for assessing runoff potential

Numerous moving spray-plate center-pivot sprinklers are commercially available providing a range of drop size distributions and wetted diameters. A means to quantitatively compare sprinkler choices in regards to maximizing infiltration and minimizing runoff is currently lacking. The objective of this study was to develop a soil independent quantitative runoff potential index to facilitate selection of sprinklers for center-pivot sprinkler irrigation systems. Drop sizes, velocities and water application rates of numerous moving spray-plate sprinklers were measured in the laboratory over a range of flow rates and operating pressures. The proposed sprinkler runoff index is based on application rates of kinetic energy and water computed by overlapping specific power and water application profiles of sprinklers equally spaced 3 m along a center-pivot lateral. Results show that substantial differences in runoff potential exist between sprinkler choices and several sprinklers can have similar runoff potential index values. In some cases, equivalent potential runoff index values were obtained with compensating differences in specific power and application rate. The proposed sprinkler runoff index provides a new and unique approach for evaluating moving spray-plate sprinklers in regards to runoff potential and provides an effective means for comparing sprinkler choices by identifying sprinklers with large drops and relatively small wetted diameters

A see-saw in Pacific Subantarctic Mode Water formation driven by atmospheric modes

Subantarctic Mode Water (SAMW) in the Pacific forms in two distinct pools in the south central and southeast Pacific, which subduct into the ocean interior and impact global storage of heat and carbon. Wintertime thickness of the central and eastern SAMW pools vary predominantly out of phase with each other, by up to ±150 m between years, resulting in an interannual thickness see‐saw. The thickness in the eastern (central) pool is found to be strongly positively (negatively) correlated with both the Southern Annular Mode (SAM) and El Niño Southern Oscillation (ENSO). The relative phases of the SAM and ENSO set the SAMW thickness, with in phase reinforcing modes in 2005‐2008 and 2012‐2017 driving strong differences between the pools. Between 2008‐2012 out of phase atmospheric modes result in less coherent SAMW patterns. SAMW thickness is dominated by local formation driven by SAM and ENSO modulated wind stress and turbulent heat fluxes

Droplet Kinetic Energy of Moving Spray-Plate Center-Pivot Irrigation Sprinklers

The kinetic energy of discrete water drops impacting a bare soil surface generally leads to a drastic reduction in water infiltration rate due to formation of a seal on the soil surface. Under center-pivot sprinkler irrigation, kinetic energy transferred to the soil prior to crop canopy development can have a substantial effect on seasonal runoff and soil erosion, especially when the soil is not protected by crop residue cover. Droplet kinetic energy of seven commercial off-center action rotating spray-plate sprinklers was characterized over a range of flow rates and pressures. Sprinkler droplet kinetic energy was characterized using two methods; droplet kinetic energy per unit sprinkler discharge and droplet kinetic energy applied per unit water depth under center-pivot irrigation with 3 m sprinkler spacing. The two methods are correlated but kinetic energy per unit sprinkler discharge does not represent droplet kinetic energy applied to the soil under center pivot irrigation as the correlation is not 1:1. Droplet kinetic energy applied for a given flow rate and operating pressure varied by up to 200% among the sprinklers evaluated. Designing sprinklers that minimize kinetic energy transferred to bare soil will require a monotonic decreasing application rate with radial distance as any peak in application rate at large radial distances will result in a peak in specific power. Kinetic energy per unit drop volume will always increase with radial distance as drops sizes get larger with radial distance. The sprinkler with the lowest droplet kinetic energy applied or lowest average composite specific power may not necessarily be the sprinkler that results in the greatest infiltrated depth or least potential runoff. Thus, droplet kinetic energy is not suitable as a single parameter to select between sprinkler choices