Lake size shapes the temperature dependence of methane emissions in cryosphere lakes

Lakes in cryospheric regions are increasingly recognized as important but uncertain contributors to global methane (CH₄) budgets. Because CH₄ production and release are highly temperature sensitive, rapid warming in cryospheric regions is expected to amplify lake emissions and play a substantial role in climate feedback mechanisms. However, the response of CH₄ emissions in cryosphere lakes to warming across lake sizes remains underexplored. Using a large, standardized dataset spanning a broad range of lake sizes, we show that diffusive and ebullitive CH₄ fluxes display higher apparent temperature dependences in larger and deeper lakes compared to smaller and shallower systems. These results demonstrate that lake surface area and depth amplify the temperature dependence of CH₄ emissions. Our findings highlight the importance of accounting for lake-size structure when assessing future CH₄ dynamics under accelerated cryosphere warming and shifting lake extent.