BODC Cruise Metadata Report for RRS James Cook (740H) cruise JC123

Introduction

This report collates information from the BODC cruise inventory and oceanographic databases. It presents

Cruise Inventory Information
A summary of BODC data holdings for the cruise from the
- National Oceanographic Database
- Projects Database
References - including cruise tracks and cruise reports

Cruise Inventory Information

Long name	RRS James Cook (740H) cruise JC123
Short name	JC123
Objectives and Narrative	Cruise JC123 was the second of two cruises on the UK research vessel the RRS James Cook related to the research project BRITICE-CHRONO: constraining rates and style of marine-influenced ice sheet decay. BRITICE-CHRONO is a five-year research project that brings together more than 40 researchers comprising glaciologists, marine and terrestrial Quaternary scientists and ice-sheet modellers. It involves researchers from eight UK universities, plus the British Geological Survey, British Antarctic Survey, NERC's radiocarbon facility and Scottish Universities Environmental Research Centre as well as project partners in Ireland, Italy, Sweden and Norway. The overall aim of the project is to provide the World's best reconstruction of the demise of a marine-based ice sheet and one that will be critical in developing and testing the next generation of ice sheet models. To achieve this we seek to answer the following research questions: 1. How do marine-based ice sheets deglaciate? By steady, stepped or catastrophic retreat, or partial 'float-off'? 2. What is the main driver(s) of retreat and what is the relative importance of climate change vs. sea level rise? 3. How is ice loss affected as the ice sheet margin crosses the marine-terrestrial transition? Once it back-steps onto land for how long does it stabilise, is it prone to quasi-stable oscillations? 4. What is the glaciological significance of ice rafted detritus (IRD)? This is fundamental for resolving the above because there is current uncertainty as to whether an IRD layer represents ice sheet margin advance or retreat. 5. Which ice sheet model implementations of iceberg calving, grounding line dynamics and ice stream mechanics are best suited for predicting ice sheet retreat? The focus of BRITICE-CHRONO is on retreat rates from marine-calving to terrestrial-melting margins and this requires that effort is split between these environments. The marine and terrestrial work is fully integrated and follows a common sampling strategy and procedure. Research effort is organised via a series of 8 transects from the continental shelf edge to a short distance (~30 km) onshore. The marine component utilises existing geophysical data archives supplied through our collaboration with the Geological Survey of Ireland and University of Maynooth, and also from British Geological Survey to identify target locations.
Ship	RRS James Cook
Departure Port	Southampton, United Kingdom
Departure Date	2015-07-03
Arrival Port	Southampton, United Kingdom
Arrival Date	2015-08-02
Principal Scientist(s)	Colm O'Cofaigh (University of Durham Department of Geography)
Responsible Organisation	University of Durham Department of Geography
Associated Project(s)	BRITICE-CHRONO
IHB Sea Areas Visited	North Sea, Inner Seas off the West Coast of Scotland, North East Atlantic Ocean (limit 40W)
Marsden Squares Visited	181/216;1/216;3/217;1/252;1
Work Area Description	The Minch. Continental shelf east and west of the Shetlands. North Sea.
Unable to lookup cruise bounds at this time
Work Area Bounding Polygon
Southern Limit	unknown
Northern Limit	unknown
Western Limit	unknown
Eastern Limit	unknown

Cruise Inventory Datasets

Geology and geophysics
Core - rock	Quantity: number of cores = 179 Description: Vibrocores up to 6 m long and piston cores up to 8 m long.
Multi-beam echosounding	Quantity: track kilometres = 8970 Description: Kongsberg Simrad EM710. Run continuously throughout the cruise and data acquirded along the track shown in the cruise track chart below.
Other geological/geophysical measurements	Quantity: track kilometres = 8970 Description: Kongsberg Simrad SBP120 sub-bottom profiler. Run continuously throughout the cruise and data acquirded along the track shown in the cruise track chart below.