The Yedoma layer, a permafrost layer containing a massive amount of underground ice in the Arctic regions, is reported to be rapidly thawing. In this study, we develop the Permafrost Degradation and Greenhouse gasses Emission Model (PDGEM), which describes the thawing of the Arctic permafrost including the Yedoma layer due to climate change and the greenhouse gas (GHG) emissions. The PDGEM includes the processes by which high-concentration GHGs (CO₂ and CH₄) contained in the pores of the Yedoma layer are released directly by dynamic degradation, as well as the processes by which GHGs are released by the decomposition of organic matter in the Yedoma layer and other permafrost. Our model simulations show that the total GHG emissions from permafrost degradation in the RCP8.5 scenario was estimated to be 31-63 PgC for CO₂ and 1261-2821 TgCH₄ for CH₄ (68^th percentile of the perturbed model simulations, corresponding to a global average surface air temperature change of 0.05–0.11 °C), and 14-28 PgC for CO₂ and 618-1341 TgCH₄ for CH₄ (0.03–0.07 °C) in the RCP2.6 scenario. GHG emissions resulting from the dynamic degradation of the Yedoma layer were estimated to be less than 1% of the total emissions from the permafrost in both scenarios, possibly because of the small area ratio of the Yedoma layer. An advantage of PDGEM is that geographical distributions of GHG emissions can be estimated by combining a state-of-the-art land surface model featuring detailed physical processes with a GHG release model using a simple scheme, enabling us to consider a broad range of uncertainty regarding model parameters. In regions with large GHG emissions due to permafrost thawing, it may be possible to help reduce GHG emissions by taking measures such as restraining land development.

据报道，耶多马层是北极地区含有大量地下冰的永久冻土层，正在迅速融化。在这项研究中，我们开发了永久冻土退化和温室气体排放模型（PDGEM），该模型描述了由于气候变化和温室气体（GHG）排放导致的北极永久冻土（包括耶多马层）的融化。 PDGEM包括Yedoma层孔隙中含有的高浓度GHGs（CO ₂和CH ₄ ）通过动态降解直接释放的过程，以及通过有机物分解释放GHGs的过程。耶多玛层和其他永久冻土层。我们的模型模拟显示，在 RCP8.5 情景中，永久冻土退化造成的温室气体排放总量估计为 31-63 PgC（CO _2）和 1261-2821 TgCH ₄ （CH _4） （扰动模型模拟的^第68 个百分位数，对应于RCP2.6 情景中，全球平均地表气温变化为 0.05–0.11 °C)，CO ₂变化为 14-28 PgC，CH ₄变化为 618-1341 TgCH ₄ (0.03–0.07 °C)。在这两种情况下，耶多玛层动态退化造成的温室气体排放量估计不到永久冻土总排放量的 1%，这可能是因为耶多玛层的面积比例较小。 PDGEM 的一个优点是，可以通过将具有详细物理过程的最先进的地表模型与使用简单方案的温室气体排放模型相结合来估计温室气体排放的地理分布，使我们能够考虑广泛的不确定性关于模型参数。 在因多年冻土融化导致温室气体排放量较大的地区，可以通过采取限制土地开发等措施来帮助减少温室气体排放。