Home
| | Home | | My BADC | | Data | | Search | | Community | | Help | |
 | Get Data | Access Rules | Submit Data | Dataset Index |  |
Introduction
The thermohaline circulation is a global ocean circulation, driven by differences in the density of the sea water that is controlled by temperature (thermal) and salinity (haline). In the north Atlantic, the thermohaline circulation transports warm and salty water to the north, where it, together with the North Atlantic Drift (the north-eastern most extension of the Gulfstream), contributes to the warm sea surface along the coast of western Europe and to the relatively mild European winters. From ice cores drilled in Greenland, there is evidence that rapid climate changes took place during the last glacial (the period roughly from 100,000 to 20,000 years before present): over a period of just several decades, northern European winter temperature dropped by as much as 10 degrees for periods typically lasting 1000 years. The present explanation is that large, pulse-like freshwater fluxes (probably from icebergs that originated from the continental ice sheets) were released into the north Atlantic where they weakened or shut down the thermohaline circulation. In a warmer greenhouse climate, it is also likely that the freshwater flux into the north Atlantic will increase; using a scenario of doubling CO2 within the next 70 years, most atmospheric models predict an increase in precipitation in high latitudes. One of the great uncertainties in these projections is the role of the Greenland ice sheet, which is situated in the middle of the area of interest. We know so little about the variability in its meltwater production and its sensitivity to regional warming that its contribution to the problem of the north Atlantic thermohaline circulation is often ignored, in spite of the fact that the Greenland ice sheet contains enough water to rise global sea level by 6 m! In this proposed research we will quantify in detail how, where and when the Greenland ice sheet has fed fresh water through iceberg calving, subglacial melting and meltwater runoff into the surrounding ocean during the last half century. The melting and runoff is calculated using a coupled snow - atmosphere model that is run over Greenland at very high resolution (11 km in the horizontal), which will take about 1 year on a supercomputer to run! The resulting data will be used by the oceanographical community as a boundary condition for their models of the north-Atlantic thermohaline circulation.
Project Duration: 1 Jun 2005 - 30 Nov 2008
This project is funded by UK NERC, Netherlands Organisation for Scientific Research and the Research Council of Norway - Grant Ref. NE/C51631X/1 - through the RAPID Climate Change NERC directed mode programme.
Access to data and information
Data and software supplied from this project to the BADC will be stored in the BADC RAPID archive.
Access to the archive is currently restricted to participants to this particular project. If you are a programme participant and would like to access this RAPID project data, then please apply for access* to the RAPID data.
You will be requested to abide by the
RAPID Climate Change Data Policy.
Data management, availability and use are ruled by the
RAPID Climate Change Programme Data Management Plan
(PDF document).
Access to Hadley Centre model data held at the BADC is subject to the signature of the NERC-Met Office agreement.
* Note that to apply for access to this dataset, you should first register as a BADC user (anyone is allowed to register). If you are already a registered BADC user, skip this step. If you have forgotten your BADC user ID and/or password, please contact the BADC helpdesk at badc@rl.ac.uk. To register as a new BADC user, please follow the instructions online.
Citation
Who to contact
General queries about these pages ir browsing the data should be directed to the BADC Support Line.
 | Home | Contact | Disclaimer | Last Modified:
|  |
Back to RAPID Home page