Abstract
Abstract. Observed and modelled landfast ice thickness variability and trends spanning more than 5 decades within the Canadian Arctic Archipelago (CAA) are summarized. The observed sites (Cambridge Bay, Resolute, Eureka and Alert) represent some of the Arctic's longest records of landfast ice thickness. Observed end-of-winter (maximum) trends of landfast ice thickness (1957–2014) were statistically significant at Cambridge Bay (−4.31 ± 1.4 cm decade−1), Eureka (−4.65 ± 1.7 cm decade−1) and Alert (−4.44 ± 1.6 cm −1) but not at Resolute. Over the 50+-year record, the ice thinned by ∼ 0.24–0.26 m at Cambridge Bay, Eureka and Alert with essentially negligible change at Resolute. Although statistically significant warming in spring and fall was present at all sites, only low correlations between temperature and maximum ice thickness were present; snow depth was found to be more strongly associated with the negative ice thickness trends. Comparison with multi-model simulations from Coupled Model Intercomparison project phase 5 (CMIP5), Ocean Reanalysis Intercomparison (ORA-IP) and Pan-Arctic Ice-Ocean Modeling and Assimilation System (PIOMAS) show that although a subset of current generation models have a "reasonable" climatological representation of landfast ice thickness and distribution within the CAA, trends are unrealistic and far exceed observations by up to 2 orders of magnitude. ORA-IP models were found to have positive correlations between temperature and ice thickness over the CAA, a feature that is inconsistent with both observations and coupled models from CMIP5.
Highlights
The World Meteorological Organization (WMO, 1970) defines landfast sea ice as “sea ice which remains fast along the coast, where it is attached to the shore, to an ice wall, to an ice front, or over shoals, or between grounded icebergs”
The representation of Canadian Arctic Archipelago (CAA) landfast sea ice thickness within the Coupled Model Intercomparison project phase 5 (CMIP5) is analysed using the 1850–2005 Historical experiment followed by the 2006–2099 Representative Concentration Pathway 8.5 (RCP85) experiment (Taylor et al, 2012)
We investigate ice thickness values from a selection of the highest-resolution models (Storto et al, 2011; Forget et al, 2015; Haines et al, 2014; Zuo et al, 2015; Masina et al, 2015), from the Ocean Reanalysis Intercomparison (ORA-IP) (Balmaseda et al, 2015; Chevallier et al, 2016) (Table 2) and from the Pan-Arctic Ice-Ocean Modeling and Assimilation System (PIOMAS) (Zhang and Rothrock, 2003)
Summary
The World Meteorological Organization (WMO, 1970) defines landfast sea ice as “sea ice which remains fast along the coast, where it is attached to the shore, to an ice wall, to an ice front, or over shoals, or between grounded icebergs”. This analysis examines the trends of measured landfast ice thickness, snow depth and air temperature over a 50+-year period between 1957 and 2014 and compares the results with the earlier analysis by BC92. We use this observational foundation to evaluate the representativeness of landfast ice in state-of-the-art global climate models, assimilation systems and reanalysis products. In recent years some global climate models, reanalysis products and
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
