Ice‐melt period dominates annual carbon dioxide evasion from clear‐water Arctic lakes

Abstract

Abstract Current estimates of carbon dioxide (CO 2 ) evasion from Arctic lakes are highly uncertain because few studies integrate seasonal variability, specifically evasion during spring ice‐melt. We quantified annual CO 2 evasion for 14 clear‐water Arctic lakes in Northern Sweden through mass balance (ice‐melt period) and high‐frequency loggers (open‐water period). On average, 80% (SD: ± 18) of annual CO 2 evasion occurred within 10 d following ice‐melt. The contribution of the ice‐melt period to annual CO 2 evasion was high compared to earlier studies of Arctic lakes (47% ± 32%). Across all lakes, the proportion of ice‐melt : annual CO 2 evasion was negatively related to the dissolved organic carbon concentration and positively related to the mean depth of the lakes. The results emphasize the need for measurements of CO 2 exchange at ice‐melt to accurately quantify CO 2 evasion from Arctic lakes.