Multidecadal Arctic sea ice thickness and volume derived from ice age

Abstract

Abstract. Sea ice is a key component of the Arctic climate system, and has impacts on global climate. Ice concentration, thickness, and volume are among the most important Arctic sea ice parameters. This study presents a new record of Arctic sea ice thickness and volume from 1984 to 2018 based on an existing satellite-derived ice age product. The relationship between ice age and ice thickness is first established for every month based on collocated ice age and ice thickness from submarine sonar data (1984–2000) and ICESat (2003–2008) and an empirical ice growth model. Based on this relationship, ice thickness is derived for the entire time period from the weekly ice age product, and the Arctic monthly sea ice volume is then calculated. The ice-age-based thickness and volume show good agreement in terms of bias and root-mean-square error with submarine, ICESat, and CryoSat-2 ice thickness, as well as ICESat and CryoSat-2 ice volume, in February–March and October–November. More detailed comparisons with independent data from Envisat for 2003 to 2010 and CryoSat-2 from CPOM, AWI, and NASA GSFC (Goddard Space Flight Center) for 2011 to 2018 show low bias in ice-age-based thickness. The ratios of the ice volume uncertainties to the mean range from 21 % to 29 %. Analysis of the derived data shows that the ice-age-based sea ice volume exhibits a decreasing trend of −411 km3 yr−1 from 1984 to 2018, stronger than the trends from other datasets. Of the factors affecting the sea ice volume trends, changes in sea ice thickness contribute more than changes in sea ice area, with a contribution of at least 80 % from changes in sea ice thickness from November to May and nearly 50 % in August and September, while less than 30 % is from changes in sea ice area in all months.

Arctic and Antarctic Sea Ice Mean State in the Community Earth System Model Version 2 and the Influence of Atmospheric Chemistry

“…In (b) the NSIDC sea ice index (Fetterer et al, 2017) is shown in blue. In (d) the reference sea ice volume for PIOMAS (Schweiger et al, 2011) and GIOMAS (Zhang & Rothrock, 2003) are shown in light blue and dark blue, respectively, and (e) includes both the PIOMAS reference sea ice volume and the ice age ice volume (Liu et al, 2020) in orange.…”

Investigation of the Arctic Sea ice volume from 2002 to 2018 using multi‐source data

“…Liu et al . (2020) indicated that the changes in the SIT contribute 80% or more to the SIV trend and that the changes in the SIA contribute less than 30% to the SIV trend from November to May. Thus, the proportion of MYI declines with SIT thinning, which contributes to a large decrease in the SIV.…”

“…Such anomalous warm air temperatures resulted in relatively thin sea ice during the growth season from 2015 to 2016 (Ricker et al ., 2017), which partly explains the small SIV value in 2016, as shown in Figure 7. The negative trends during the Envisat period and the insignificant variability trend during the CS‐2 period are similar to the results found in previous studies (Kwok, 2018; Liu et al ., 2020).…”

“…The monthly mean values of the SAT and SST are calculated by averaging all the pixels in a month based on the method by Liu et al . (2020). The SIV has a clear negative correlation with the SAT and SST (Figure 13).…”

“…The DRA is an irregular polygon covering approximately 38% of the Arctic Ocean (Figure 1). SIT variability in the DRA was low during the CS‐2 period (2010–2018) (Kwok, 2018; Liu et al ., 2020).…”