The CLIMODE field campaign : observing the cycle of convection and restratification over the Gulf Stream

Author Posting. © American Meteorological Society, 2009. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 90 (2009): 1337-1350, doi:10.1175/2009BAMS2706.1.A major oceanographic field experiment is described, which is designed to observe, quantify, and understand the creation and dispersal of weakly stratified fluid known as “mode water” in the region of the Gulf Stream. Formed in the wintertime by convection driven by the most intense air–sea fluxes observed anywhere over the globe, the role of mode waters in the general circulation of the subtropical gyre and its biogeo-chemical cycles is also addressed. The experiment is known as the CLIVAR Mode Water Dynamic Experiment (CLIMODE). Here we review the scientific objectives of the experiment and present some preliminary results.Physical Oceanography program of NS

Variability in the Deep Western Boundary Current : local versus remote forcing

Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 117 (2012): C12022, doi:10.1029/2012JC008369.Horizontal velocity, temperature and salinity measurements from the Line W array for the period 2004–2008 show large changes in the water mass structure and circulation of the Deep Western Boundary Current (DWBC). Fluctuations in the flow with periods from 10 to 60 days are bottom intensified: signals most likely associated with topographic Rossby waves (TRW). A fraction (∼15%) of the DWBC transport variability is caused by Gulf Stream rings and meanders. These flow anomalies are surface intensified and fluctuate at frequencies lower than the TRW. Interannual variability in the velocity field appears to be related to changes in the hydrographic properties. The dominant mode of variability is characterized by an overall freshening, cooling, a potential vorticity (PV) increase in the deep Labrador Sea Water (dLSW) and a PV decrease in the Overflow Water (OW). The variability in the flow associated with these property changes is not spatially homogeneous. Offshore (water depths larger than 3500 m) changes in the velocity are in phase with PV changes in the OW: a decrease in the OW PV is accompanied by an increase in the southward (negative) transport. Conversely, variations of the inshore flow are in phase with changes in the dLSW PV (increasing PV and decreasing transport). This trend, true for most of the record, reverses after the winter of 2007–2008. A sudden decrease of the dLSW PV is observed, with a corresponding intensification of the flow in the inner DWBC as well as a northward shift in the Gulf Stream axis.Financial support for the Line W program (2004–2008) was provided by the U.S. National Science Foundation (grants OCE-0241354 and OCE-0726720) as well as funding from the WHOI’s Ocean and Climate Change Institute.2013-06-2

Understanding success in the context of brownfield greening projects: The requirement for outcome evaluation in urban greenspace success assessment

Many European governments place strong emphasis on integrated land use policies, particularly the re-establishment of public open access greenspaces through brownfield land regeneration. The UK Government considers the regeneration of brownfield land a prime tool for the delivery of regional economic regeneration, neighbourhood renewal and international biodiversity commitments. A number of failed brownfield greening projects question both the sustainability of such undertakings and whether greenspaces are fulfilling the functions they were designed for. Reliance on developer-, funding body- and site owner-centric notions of success in project delivery evaluation, to the exclusion of social and environmental impacts, has failed to highlight revenue requirements for management and maintenance to maintain function and quality. Brownfield greening project aims and objectives can be characterised as inputs, processes, outputs and outcomes using the general organisational ‘logic’ framework model. Applying this framework to six UK case studies, this research demonstrated that most greenspace aims and objectives are in fact ‘outcomes’ delivered in the medium and long terms following regeneration. The model is supportive of integrated, stakeholder inclusive monitoring over short, medium and long time periods. Physicochemical and social data from the case study sites were employed to present a comprehensive evaluation of site success. In each case, a lack of monitoring and evaluation – combined with insufficient supporting revenue funds – failed to highlight site issues, changes in local emphasis and ultimately a lack of success with respect to project aims and site sustainability. This research supports claims that capital funds to regenerate land must be supported by a revenue package for management and maintenance, that monitoring must be a funded activity; and, that monitoring and evaluation in support of the management cycle will promote the long-term sustainability, value and use of a greenspace