ACSIS

Enhancing the UK’s capability to detect, attribute and predict changes in the North Atlantic Climate System

The North Atlantic climate system is undergoing changes that are unprecedented in the instrumental record.  These also affect the UK’s climate and weather, with major economic impacts on fisheries, water, energy and health. Led by NCAS, in partnership with CPOM, NOC, BAS, PML and NCEO, ACSIS is delivering a step change in our understanding and predictive capability of the complex ice-ocean-atmosphere interactions involved.

CPOM’s role is to develop multi-decadal satellite datasets to quantify the freshwater fluxes from Greenland and from Arctic sea ice, and to conduct high resolution, observationally constrained sea ice-ocean simulations to establish the processes controlling sea ice decline and their wider impact on the ocean.

Our sea ice volume estimates are based on satellite observations of freeboard height, which are then converted to thickness and volume to give a continuous ongoing record of Arctic sea ice and Greenland volume change.

Variable
Satellite Instrument Time Span Resolution
Temporal Horizontal Vertical
Land ice and sea ice elevation
CryoSat-2 2010-present 369-day, 30-day sub cycle 0.3 (along track) x 1 (across track) km < 4 cm
ERS1&2 1992-2011 35-day 10 km < 10 cm
EnviSat 2002-2012 35-day 10 km < 10 cm

 

We are also using our sea ice model to provide numerical simulations of unsurpassed sophistication, due to the inclusion of form drag, anisotropic rheology and melt ponds, and is systematically calibrated using our unique satellite observations.  In addition, CPOM is providing a diagnosis of trends and variability in Arctic sea ice with analysis of energy and mass budgets to determine proximate cause of changes; and attribution of changes in Arctic sea ice in both the observations and simulations.