255 research outputs found
Reduction of the virtual space for coupled-cluster excitation energies of large molecules and embedded systems
Peer reviewe
Single-shot full strain tensor determination with microbeam X-ray Laue diffraction and a two-dimensional energy-dispersive detector
SENCO Induction Pack: Supporting you at the start of your journey.
The National Award for SENCO Providers Group (Leading Learning for Special Educational Needs and Disability CiC), as part of Whole School SEND and funded by the DfE, has developed an Induction Pack aimed at new and aspiring SENCOs. This pack is now available on the SEND Gateway.
The aim of the pack is to support SENCOs at the start of their journey, before they complete the NASENCO qualification, but it is also likely to prove useful for more experienced SENCOs as a quick reference tool. It contains useful summaries of information and areas for SENCOs to consider, as well as many references and links to documents and websites. The pack has been trialled with new and experienced SENCOs and feedback has been very positive
BASEWECS - Influence of the Baltic Sea and its annual ice coverage on the water and energy budget of the Baltic Sea
BASEWECS is a contribution to the German Climate Research Program DEKLIM. The project started in May 2001 and lasted until December 2004. BASEWECS aimed at the investigation of the influence of the Baltic Sea and its annual ice coverage on the water and energy budget of the BALTEX are
Autonomous Ocean Measurements in the California Current Ecosystem
Event-scale phenomena, of limited temporal duration or restricted spatial extent, often play a disproportionately large role in ecological processes occurring in the ocean water column. Nutrient and gas fluxes, upwelling and downwelling, transport of biogeochemically important elements, predator-prey interactions, and other processes may be markedly influenced by such events, which are inadequately resolved from infrequent ship surveys. The advent of autonomous instrumentation, including underwater gliders, profiling floats, surface drifters, enhanced moorings, coastal high-frequency radars, and satellite remote sensing, now provides the capability to resolve such phenomena and assess their role in structuring pelagic ecosystems. These methods are especially valuable when integrated together, and with shipboard calibration measurements and experimental programs
CODE-2 : moored array and large-scale data report
The Coastal Ocean Dynamics Experiment
(CODE) was undertaken to identify and study
the important dynamical processes which
govern the wind-driven motion of coastal
water over the continental shelf. The
initial effort in this multi-year, multi-institutional
research program was to obtain
high-quality data sets of all the
relevant physical variables needed to construct
accurate kinematic and dynamic descriptions
of the response of shelf water
to strong wind forcing in the 2 to 10 day
band. A series of two small-scale, densely-
instrumented field experiments of approximately
four months duration (called CODE-1
and CODE-2) were designed to explore and
to determine the kinematics and momentum
and heat balances of the local wind-driven
flow over a region of the northern California
shelf which is characterized by both
relatively simple bottom topography and
large wind stress events in both winter
and summer. A more lightly instrumented,
long -term, large-scale component was
designed to help separate the local wind-driven
response in the region of the small-scale
experiments from motions generated
either offshore by the California Current
system or in some distant region along the
coast, and also to help determine the seasonal
cycles of the atmospheric forcing,
water structure, and coastal currents over
the northern California shelf.
The first small-scale experiment
(CODE-1) was conducted between April and
August, 1981 as a pilot study in "which
primary emphasis was placed on characterizing
the wind-driven "signal" and the
"noise" from which this signal must be
extracted. In particular, CODE-1 was
designed to identify the key features of
the circulation and its variability over
the northern California shelf and to
determine the important time and length
scales of the wind-driven response. The
second small-scale experiment (CODE-2) was
conducted between April and August, 1982
and was designed to sample more carefully
the mesoscale horizonta1 variability
observed in CODE-1. This report presents a
basic description of the moored array data
and some other Eulerian data collected
during CODE-2. A brief description of the
CODE-2 field program is presented first,
followed by a description of the common
data analysis procedures used to produce
the various data sets presented here. Then
basic descriptions of the following data
sets are presented: (a) the coastal and
moored meteorological measurements, (b)
the moored current measurements, (c) array
plots of the surface wind stress and near-surface
current measurements, (d) the
moored temperature and conductivity observations,
(e) the bottom pressure measurements,
and (f) the wind and adjusted
coastal sea level observations obtained as
part of the CODE-2 large-scale component.This work has
been supported by the National Science
Foundation
Using present-day observations to detect when anthropogenic change forces surface ocean carbonate chemistry outside preindustrial bounds
© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Biogeosciences 13 (2016): 5065-5083, doi:10.5194/bg-13-5065-2016.One of the major challenges to assessing the impact of ocean acidification on marine life is detecting and interpreting long-term change in the context of natural variability. This study addresses this need through a global synthesis of monthly pH and aragonite saturation state (Ωarag) climatologies for 12 open ocean, coastal, and coral reef locations using 3-hourly moored observations of surface seawater partial pressure of CO2 and pH collected together since as early as 2010. Mooring observations suggest open ocean subtropical and subarctic sites experience present-day surface pH and Ωarag conditions outside the bounds of preindustrial variability throughout most, if not all, of the year. In general, coastal mooring sites experience more natural variability and thus, more overlap with preindustrial conditions; however, present-day Ωarag conditions surpass biologically relevant thresholds associated with ocean acidification impacts on Mytilus californianus (ΩaragâŻ<âŻ1.8) and Crassostrea gigas (ΩaragâŻ<âŻ2.0) larvae in the California Current Ecosystem (CCE) and Mya arenaria larvae in the Gulf of Maine (ΩaragâŻ<âŻ1.6). At the most variable mooring locations in coastal systems of the CCE, subseasonal conditions approached Ωaragâ=ââŻ1. Global and regional models and data syntheses of ship-based observations tended to underestimate seasonal variability compared to mooring observations. Efforts such as this to characterize all patterns of pH and Ωarag variability and change at key locations are fundamental to assessing present-day biological impacts of ocean acidification, further improving experimental design to interrogate organism response under real-world conditions, and improving predictive models and vulnerability assessments seeking to quantify the broader impacts of ocean acidification.The CO2 and ocean acidification observations
were funded by NOAAâs Climate Observation Division (COD)
in the Climate Program Office and NOAAâs Ocean Acidification
Program. The maintenance of the Stratus and WHOTS
Ocean Reference Stations were also supported by NOAA COD
(NA09OAR4320129). Additional support for buoy equipment,
maintenance, and/or ancillary measurements was provided by
NOAA through the US Integrated Ocean Observing System
office: for the La Parguera buoy under a Cooperative Agreement
(NA11NOS0120035) with the Caribbean Coastal Ocean Observing
System, for the ChĂĄ bËa buoy under a Cooperative Agreement
(NA11NOS0120036) with the Northwest Association of Networked
Ocean Observing System, for the Grayâs Reef buoy under
a Cooperative Agreement (NA11NOS0120033) with the Southeast
Coastal Ocean Observing Regional Association, and for the Gulf of
Main buoy under a Cooperative Agreement (NA11NOS0120034)
with the Northeastern Regional Association of Coastal and Ocean
Observing Systems
Characterizing, modelling and understanding the climate variability of the deep water formation in the North-Western Mediterranean Sea
Observing, modelling and understanding the climate-scale variability of the deep water formation (DWF) in the North-Western Mediterranean Sea remains today very challenging. In this study, we first characterize the interannual variability of this phenomenon by a thorough reanalysis of observations in order to establish reference time series. These quantitative indicators include 31 observed years for the yearly maximum mixed layer depth over the period 1980â2013 and a detailed multi-indicator description of the period 2007â2013. Then a 1980â2013 hindcast simulation is performed with a fully-coupled regional climate system model including the high-resolution representation of the regional atmosphere, ocean, land-surface and rivers. The simulation reproduces quantitatively well the mean behaviour and the large interannual variability of the DWF phenomenon. The model shows convection deeper than 1000 m in 2/3 of the modelled winters, a mean DWF rate equal to 0.35 Sv with maximum values of 1.7 (resp. 1.6) Sv in 2013 (resp. 2005). Using the model results, the winter-integrated buoyancy loss over the Gulf of Lions is identified as the primary driving factor of the DWF interannual variability and explains, alone, around 50 % of its variance. It is itself explained by the occurrence of few stormy days during winter. At daily scale, the Atlantic ridge weather regime is identified as favourable to strong buoyancy losses and therefore DWF, whereas the positive phase of the North Atlantic oscillation is unfavourable. The driving role of the vertical stratification in autumn, a measure of the water column inhibition to mixing, has also been analyzed. Combining both driving factors allows to explain more than 70 % of the interannual variance of the phenomenon and in particular the occurrence of the five strongest convective years of the model (1981, 1999, 2005, 2009, 2013). The model simulates qualitatively well the trends in the deep waters (warming, saltening, increase in the dense water volume, increase in the bottom water density) despite an underestimation of the salinity and density trends. These deep trends come from a heat and salt accumulation during the 1980s and the 1990s in the surface and intermediate layers of the Gulf of Lions before being transferred stepwise towards the deep layers when very convective years occur in 1999 and later. The salinity increase in the near Atlantic Ocean surface layers seems to be the external forcing that finally leads to these deep trends. In the future, our results may allow to better understand the behaviour of the DWF phenomenon in Mediterranean Sea simulations in hindcast, forecast, reanalysis or future climate change scenario modes. The robustness of the obtained results must be however confirmed in multi-model studies
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