Abrupt Climate Shifts and Extremes over Eurasia In Response to Arctic Sea Ice Change (ACE)_ENG_

Abrupt Climate Shifts and Extremes over Eurasia In Response to Arctic Sea Ice Change (ACE)

BMBF-funded German-Sino Cooperation Program in Climate Research
Funding identification number (FZK): 01LP2004A
Cost (Kostenstelle): DM 87011015
Project duration: 01. Juli 2021 - 31. Mai 2024
Applicants: Prof. Dr. Gerrit Lohmann | Dr. Monica Ionita-Scholz | Prof. Dr. Xun Gong, University of Geoscience , Wuhan, China
PostDoc: Dr. Dmitry Sein

We examine the climate relationship between the Arctic and the mid- latitudes, focusing on the abrupt changes and extremes in the Eurasian climate system in response to the temporal fluctuations of the Arctic. In this project, we will systematically create a database for the Arctic and Eurasian regions in order to characterize temporal and spatial characteristics of abrupt climate changes and extremes in the Holocene. This is combined with climate modeling using the coupled Earth System Model (AWI-ESM). In addition, we will use our model to create climate projections for the next 1000 years, which provides insight into the potential upcoming climate for Germany and China.

Example: Holocene dynamics of East Asian summer monsoon and Arctic sea ice

Within this project we will incorporate different data types with the focus of finding the physical mechanism related to the variability of the Arctic sea-ice variability and its influence on the frequency of extreme evets at mid-latitudes, with a special focus on Europe and Asia. We present records of ice-rafted debris and sedimentation rates from the East Siberian Arctic Shelf to reconstruct the Holocene variations in Arctic sea ice and Russian pan-Arctic river heat discharge, respectively (Figure).

a Pan-Arctic river system, Arctic Ocean circulation (arrow lines), Northern Hemisphere westerlies (orange arrows), and East Asian summer monsoon (EASM, yellow arrows). Sea surface (b) salinity and c temperature (color scales) during July–September in the ESAS region, with mean annual Russian pan-Arctic major river runoff and sediment load (km³/yr and Mt/yr, respectively). The red dots show the locations of sediment cores. EADR, NADR, PWI, AWI, TPD, BG, and SCC are the Eurasian pan-Arctic discharge realm, North American pan-Arctic discharge realm, Pacific water inflow at a water depth of 40–220 m, Atlantic water inflow at a water depth of 200–800 m, surface Transpolar Drift, surface Beaufort Gyre, and surface Siberian Coastal Current, respectively. (Source: www.nature.com)

Our analysis (Dong et al., 2022) reveals dramatic Arctic sea-ice loss and larger river heat discharge during the mid-Holocene than during the late Holocene. In the mid-Holocene summer, intense solar insolation led to warmer conditions in the vast pan-Arctic region. Consequently, intensified thawing of land snow/ice and permafrost and more precipitation over the river basin (45–75°N) substantially multiplied river heat discharge in early summer, reducing Arctic sea ice and thus amplifying the positive influence of early summer solar insolation on sea ice decline. We apply our high-resolution model system to substantiate the hypothesis from paleoclimate data.

More information about the project ACE

References

Dong, J., X. Shi, X. Gong, Astakhov, A.S., Hu, L., Liu, X., Yang, G., Wang, Y., Vasilenko, Y., Qiao, S., Bosin, A., Lohmann, G., 2022: Enhanced Arctic sea ice melting controlled by larger heat discharge of Holocene rivers. Nature comm. 13, 5368. https://doi.org/10.1038/s41467-022-33106-1

Contzen, J., Dickhaus, T., Lohmann G.: Variability and extremes: statistical validation of the Alfred Wegener Institute Earth System Model (AWI-ESM), Geosci. Model Dev., 15, 1803–1820, https://doi.org/10.5194/gmd-15-1803-2022, 2022.

Lohmann, G., A. Wagner, M. Prange, 2021: Resolution of the atmospheric model matters for the Northern Hemisphere Mid-Holocene climate. Dynamics of Atmospheres and Oceans, 93, 101206 doi:10.1016/j.dynatmoce.2021.101206

Shi, J., C. Stepanek, D. Sein, J. Streffing, G. Lohmann, 2023: East Asian summer precipitation in AWI-CM3: Role of resolution and comparison with observations and CMIP6 models. International Journal of Climatology, DOI:10.1002/joc.8075. http://doi.org/10.1002/joc.8075

Streffing, J., Sidorenko, D., Semmler, T., Zampieri, L., Scholz, P., Andrés-Martínez, M., Koldunov, N., Rackow, T., Kjellsson, J., Goessling, H., Athanase, M., Wang, Q., Hegewald, J., Sein, D. V., Mu, L., Fladrich, U., Barbi, D., Gierz, P., Danilov, S., Juricke, S., Lohmann, G., and Jung, T.: AWI-CM3 coupled climate model: description and evaluation experiments for a prototype post-CMIP6 model, Geosci. Model Dev., 15, 6399–6427, 2022. https://doi.org/10.5194/gmd-15-6399-2022

Ionita, 2023: The Arctic Winter Seasons 2016 and 2017: Climatological Context and Analysis. Climate 2023, 11(1), 19; https://doi.org/10.3390/cli11010019

Schwertfeger, B. T., Lohmann, G., Lipskoch, H., 2023: Introduction of the BiasAdjustCXX command-line tool for the application of fast and efficient bias corrections in climatic research. SoftwareX 22, 101379, https://doi.org/10.1016/j.softx.2023.101379