A new computer model reveals how the timing of permafrost thaw in the Qinghai-Tibet Plateau affects carbon runoff. While spring thaws create highly concentrated bursts of dissolved organic carbon, deeper summer thaws lead to more dilute runoff as water moves through carbon-poor soil layers. The study suggests that long-term warming may actually decrease the total amount of carbon exported sideways from these slopes. This finding challenges the common assumption that thawing ground always increases the volume of carbon flowing into river systems.
