SISTeR

Queen Mary 2 with SISTer on starboard bridge

Sea Surface Temperature (SST) is considered one of the essential climate variables and is critical in the understanding of how oceans exchange energy with the atmosphere. Not only are SST's important in understanding climate change but they are also used as input parameters to the meteorological models which are in turn used to generate accurate weather forecasts.

A partnership between the STFC and the Carnival Group UK (Cunard's parent company) has culminated in an instrument developed by RAL Space being installed on the Queen Mary 2. The Sea Surface Temperature monitoring instrument, SISTeR (Scanning Infrared Sea Surface Temperature Radiometer), is a project aimed at validating satellite measurements and improving climate records.

An AATSR sea surface temperature map

Global measurements of SST are performed by satellite borne radiometers that detect the thermal radiation emitted from the "skin" of the sea. To ensure that the satellite measurements are accurate, SISTeR is used to provide a calibrated validation. The ground truthing is provided when the satellite and SISTeR measurements coincide and the SST is recorded at the same location by both instruments.

The Queen Mary 2 is the largest ocean liner in the world and provides the ideal platform from which to perform these measurements. SISTeR is positioned at the prominent vantage point, high on the starboard bridge wing, giving a perfect view of unbroken water. The mixture of transatlantic crossing, (from Southampton to New York) and tropical round the world cruises give an ideal combination of hot and cold water measurements which can be used to validate satellites over the wide variety of Sea Surface Temperatures.

Science and Technology Facilities Council Switchboard: 01793 442000