Compilation of thaw ponds samples collected each year.

Polygonal ponds (P); runnel ponds (R); dissolved organic carbon (DOC); organic carbon (OC); Greenhouse gases (GHG, including CO2 and CH4); ebullition is GHG released as bubbles; production pathway indicates CH4 produced by acetoclastic methanogenesis (AM) or hydrogenotrophic methanogenesis (HM); temperature (temp). Note that most samples were collected in 2009, with diurnal, ebullition and sediment OC collected in 2011, which was the only occasion when appropriate sampling gear was available.