Modelling twentieth century global ocean circulation and iceberg flux at 48°N: Implications for west Greenland iceberg discharge

We have used a coupled ocean-iceberg model to study the variation in global ocean circulation and North Atlantic iceberg flux from 1900 to 2008. The latter component of the study focused particularly on Greenland icebergs feeding into the Labrador Current and past Newfoundland. The model was forced with daily heat, freshwater and wind fluxes from the Twentieth Century Reanalysis. The reanalysis heat fluxes were shown to be offset from the, shorter, NCEP reanalysis and a grid-point correction was applied to this component of the forcing. The model produces a generally realistic ocean circulation, although with an enhanced Atlantic Meridional Overturning largely due to the forcing. The modelled iceberg flux at 48°N is well correlated with the long-term observed flux when using a modelled iceberg discharge that varies in a similar fashion to the highly variable observed flux at 48°N. From this model we infer changes in the spatial and temporal variability of iceberg calving from western Greenland. During the first third of the twentieth century the majority of modelled icebergs reaching 48°N derive from southern Greenland, while only after 1930 is the traditional perspective of a majority of such icebergs originating from Baffin Bay consistent with model results. Decadal-scale changes in the dominant regional sources are found, with oscillations between western Greenland and northern Baffin Bay. The latter origin was modelled to be most important in the last third of the twentieth century, although west Greenland sources have increased in importance in recent years. The model correctly reproduces the pronounced late spring peak in flux at 48°N for southern Greenland icebergs, but has an approximately six month offset for icebergs from Baffin Bay, most likely due to resolution issues leading to model icebergs not being delayed in shallow coastal waters, whereas in reality they may be grounded for some time or trapped in coastal sea-ice. © 2015 The Authors

Prospects for seasonal forecasting of iceberg distributions in the North Atlantic

An efficient approach to ocean–iceberg modelling provides a means for assessing prospects for seasonal forecasting of iceberg distributions in the northwest Atlantic, where icebergs present a hazard to mariners each spring. The stand-alone surface (SAS) module that is part of the Nucleus for European Modelling of the Ocean (NEMO) is coupled with the NEMO iceberg module (ICB) in a “SAS-ICB” configuration with horizontal resolution of 0.25°. Iceberg conditions are investigated for three recent years, 2013–2015, characterized by widely varying iceberg distributions. The relative simplicity of SAS-ICB facilitates efficient investigation of sensitivity to iceberg fluxes and prevailing environmental conditions. SAS-ICB is provided with daily surface ocean analysis fields from the global Forecasting Ocean Assimilation Model (FOAM) of the Met Office. Surface currents, temperatures and height together determine iceberg advection and melting rates. Iceberg drift is further governed by surface winds, which are updated every 3 h. The flux of icebergs from the Greenland ice sheet is determined from engineering control theory and specified as an upstream flux in the vicinity of Davis Strait for January or February. Simulated iceberg distributions are evaluated alongside observations reported and archived by the International Ice Patrol. The best agreement with observations is obtained when variability in both upstream iceberg flux and oceanographic/atmospheric conditions is taken into account. Including interactive icebergs in an ocean–atmosphere model with sufficient seasonal forecast skill, and provided with accurate winter iceberg fluxes, it is concluded that seasonal forecasts of spring/summer iceberg conditions for the northwest Atlantic are now a realistic prospect

Prediction of iceberg trajectories for the North Atlantic and Arctic Oceans

Icebergs are a well-known hazard for shipping. Their study also provides information about diverse geophysical processes, as varied as ocean circulation, air-sea fluxes, calving rates of glaciers or the mass balance of ice sheets. As a first step to obtaining this information from iceberg data we have developed a model of iceberg drift driven by ocean and atmospheric forcing derived from general circulation models. We have applied the drift model to a distribution of typical icebergs released from the main tidewater glaciers of the North Atlantic and Arctic Oceans. We demonstrate that the main driving force of iceberg motion is rooted in the unsteady component of oceanic advection. From simulated trajectories we are able to reproduce the observed southwards limit of iceberg penetration and demonstrate sometimes surprising geographical links between iceberg origin and ultimate melting zones. Copyright 1996 by the American Geophysical Union

Bridging the gap: A case study of a partnership approach to skills development through student engagement in bristol’s green capital year

© 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. HEIs are well placed to engage with local communities, and can connect students with organisations through several pathways, such as volunteering opportunities, placements, internships, or projects. The University of the West of England, Bristol (UWE), the University of Bristol and their respective Students’ Unions have been working in partnership with the city and local communities, using HEFCE Catalyst funding to promote student involvement in sustainability activity during Bristol’s year as European Green Capital. The Green Capital Student Capital project has created a broad programme of citywide impact through mobilising the enthusiasm of the city’s student body. It delivered a wide-ranging programme of engagement in city sustainability and in so doing developed skills, knowledge and attributes in the student body that support the development of graduate attributes and amore sustainable lifestyle. The project demonstrates how institutions can collaborate across cities and communities to have internal and external impacts for sustainability

UWE - Celebrating Bristol Green Capital 2015 activities catalogue

This catalogue showcases and celebrates examples of the work of the hundreds of UWE staff and students who contributed to Bristol Green Capital 2015

UWE Celebrating Bristol Green Capital 2015 - Activities portfolio (supporting document for UWE Celebrating Bristol Green Capital 2015 activities catalogue)

This Activities Portfolio details projects, events and initiatives which represent the work of hundreds of UWE staff and students during Bristol's year as European Green Capital in 2015. It is the working file to accompany the UWE Green Capital 2015 Activities Catalogue

Wind-driven upwelling around grounded tabular icebergs

Funding was provided by NSF Polar Programs - Grant Number: ARC-1304137.Temperature and salinity data collected around grounded tabular icebergs in Baffin Bay in 2011, 2012 and 2013 indicate wind-induced upwelling at certain locations around the icebergs. These data suggest that along one side of the iceberg, wind forcing leads to Ekman transport away from the iceberg, which causes upwelling of the cool saline water from below. The upwelling water mixes with the water in the thermocline, causing the mixed layer to become cooler and more saline. Along the opposite side of the iceberg, the surface Ekman transport moves towards the iceberg, which causes a sharpening of the thermocline as warm fresh water is trapped near the surface. This results in higher mixed layer temperatures and lower mixed layer salinities on this side of the iceberg. Based on these in situ measurements, we hypothesize that the asymmetries in water properties around the iceberg, caused by the opposing effects of upwelling and sharpening of the thermocline, lead to differential deterioration around the iceberg. Analysis of satellite imagery around iceberg PII-B-1 over a six month monitoring period reveals differential decay around the iceberg, in agreement with this mechanism.Publisher PDFPeer reviewe

The Bristol Method: Green Capital Student Capital - The power of student sustainability engagement

THE BRISTOL METHODThe Bristol Method is a knowledge-transfer programme aimed at helping people in other cities understand and apply the lessons that Bristol has learned in becoming a more sustainable city, not just in 2015 but in the last decade. Each module of the Bristol Method is presented as an easy-to-digest ‘how to’ guide on a particular topic, which use Bristol’s experiences as a case study. The modules contain generic advice and recommendations that each reader can tailor to their own circumstances.This module focusses on the Green Capital: Student Capital project, and explains how the University of the West of England, Bristol (UWE) and the University of Bristol – with their respective students’ unions – have been working in partnership with the city and local communities, using Higher Education Funding Council for England Catalyst funding to promote student involvement in Green Capital activities across Greater Bristol.Student Capital created a broad programme of citywide impact during European Green Capital. It delivered a programme of student and staff engagement in enhancing sustainability within the city and has developed student and staff engagement with sustainability action. Through action research approaches it is also providing lessons for how institutions can collaborate across cities and communities to have internal and external impacts for sustainability. This report is for anyone seeking to increase sustainability engagement. In it we tell the story of the Student Capital project, explaining the processes and the outcomes, and suggesting pieces of advice and lessons for what went well, and what could have been done better or differently

First Nd isotope record of Mediterranean–Atlantic water exchange through the Moroccan Rifian Corridor during the Messinian Salinity Crisis

We present the first neodymium isotope reconstruction of Mediterranean–Atlantic water exchange through the Moroccan (‘Rifian’) Corridor 8–5 Ma. This covers the late Miocene Messinian Salinity Crisis (MSC); a period when progressive tectonic restriction of the Mediterranean–Atlantic seaways resulted in extreme, basin-wide Mediterranean salinity fluctuations. The Rifian Corridor was one of these seaways and until now, relatively poor age constraints existed for the timing of Corridor closure, due to the impact of uplift and erosion on the sedimentary record. The bottom water Nd isotope record from the continuous Bou Regreg Valley succession in northwest Morocco allows us to explore corridor connectivity with the Atlantic. Data from the interior and Mediterranean edge of the Rifian Corridor (respectively, the Taza–Guercif and Melilla basins, northern Morocco) provide new information on corridor shallowing and the provenance of water flowing through the seaway. As a result, we can constrain the age of Rifian Corridor closure to 6.64–6.44 Ma. We also find no evidence of the siphoning of Atlantic waters through the seaway (7.20–6.58 Ma). Our results cannot exclude the possibility that at times during the Messinian Salinity Crisis, Mediterranean Outflow Water reached the Atlantic