- 1University of Manitoba, Department of Environment and Geography, Centre for Earth Observation Science, Winnipeg, Canada (armina.soleymani@umanitoba.ca, alex.crawford@umanitoba.ca)
- 2University of Waterloo, Department of Mechanical and Mechatronics Engineering, Waterloo, Canada (ka3scott@uwaterloo.ca)
The Marginal Ice Zone (MIZ) is a dynamic region between open water
and consolidated ice, crucial for heat and moisture exchange and support-
ing diverse marine ecosystems. With Arctic sea ice thinning and the melt
season lengthening, monitoring the MIZ has become increasingly impor-
tant. This study analyzed Arctic MIZ trends over 40 years (1983–2022)
using Bootstrap SIC data and two definitions: one based on the SIC
threshold (MIZt) and another on the SIC anomaly (MIZσ ). MIZt was de-
fined as 0.15 0.15 ≤ SIC < 0.80, while MIZσ used grid cells with a median
standard deviation of SIC anomaly above 0.11, derived from the probabil-
ity density function. This research represents a novel exploration of the
Arctic MIZ using a SIC anomaly-based approach. Both definitions showed
similar seasonal trends, but MIZσ peaked during freeze-up (October) and
break-up (July), while MIZt peaked in summer (August). MIZσ fractions
were consistently higher than those from MIZt across all seasons. Finally,
October and August exhibit the most rapid increases in both MIZt and
MIZσ fractions, coinciding with accelerated sea ice decline. These results
highlight the importance of selecting an MIZ definition tailored to specific
research or applications.
How to cite: Soleymani, A., Crawford, A., and Scott, K. A.: Interannual Variability of the Arctic Marginal Ice Zone Over Four Decades: A Comparison of Two Definitions, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-7366, https://doi.org/10.5194/egusphere-egu25-7366, 2025.
