Authors: Oliver Frauenfeld*, Texas A&M University, Xiaoqing Peng, Lanzhou University, Tingjun Zhang, Lanzhou University
Topics: Cryosphere, Climatology and Meteorology
Keywords: Frozen ground, Eurasia, climate change
Session Type: Paper
Start / End Time: 9:55 AM / 11:35 AM
Room: Stones Throw 1 - Granite, Marriott, Lobby Level
Presentation File: No File Uploaded
Seasonally frozen ground plays an important role in hydrological processes, the energy and moisture balance, carbon exchange, as well as ecosystem diversity and productivity. Soil freeze depth (SFD) can be a useful indicator of climate change in cold regions. However, given the limited data coverage in high latitudes and altitudes, diagnosing long-term changes in SFD remains a challenge. Here we combine observational data and model simulations to provide an overview of 250 years of change in SFD in Eurasia. We employ the Stefan solution to quantify the spatial and temporal variability of SFD under historical and projected climate change. The Climatic Research Unit (CRU) dataset and hundreds of soil and air temperature sites are used in combination with 16 CMIP5 climate models and their multi-model ensemble average. The simulations over the historical period (1850–2005) are verified based on the CRU data, and output from three representative concentration pathways (RCP 2.6, 4.5, and 8.5) are used to project 2006–2100 changes. Over the historical 1850–2005 period, we find a statistically significant SFD decrease of 0.49±0.04 cm/decade. Spatially, these changes are concentrated in Siberia and the Tibetan Plateau. The projected changes for the remainder of this century are 0.45±0.18 cm/decade, 1.85±0.21 cm/decade, or 4.58±0.26 cm/decade, depending on whether the RCP 2.6, 4.5, or 8.5 emission scenario will occur. These projections of SFD can provide insights into the spatiotemporal changes that will take place due to climate change in Eurasia, and may facilitate better understanding of future frozen ground variability.