Fifty years of firn evolution on Grigoriev ice cap, Tien Shan, Kyrgyzstan

README Grigoriev data

Overview

The Grigoriev data collection consists of the following files, which are briefly explained further below.From a relatively large number of files and for clarity, we provide mainly those files which have been directlyused in the generation of figures contained in Machguth et al. (2024). While the use in figurecreation was the main selection criteria, the files have not been truncated to data shown in the figures. The files contain more information than shown in the figures. A few files have been added for completeness althoughnot used to create figures (see below).

The data sets provided in this repository are listed in the following. Most of these tables contain relatively raw data. The suggested citations are added in brackets. Please also check Table 1 in Machguth et al. (2024) for potential further references.

- 1990_GRG_90_H1-BETA.xlsx                                          (Arkhipov et al., 1996; Thompson et al., 1997)- 1990_GRG_90_H1-CHM.xlsx                                           (Arkhipov et al., 1996; Thompson et al., 1997)- 1990_GRG_90_H1-STRAT.xlsx                                            (Arkhipov et al., 1996; Thompson et al., 1997)- 1990_GRG_90_H2-CHM.xlsx                                            (Arkhipov et al., 1996; Thompson et al., 1997)- 1990_GRG_90_H2-STRAT.xlsx                                            (Arkhipov et al., 1996; Thompson et al., 1997)- 1990_H1-H2_2018_Grigoriev_MI-decadal.xlsx                            (Arkhipov et al., 1996; Thompson et al., 1997; Machguth et al., 2024)- 2001_GRG_01_S1-EE.xlsx                                            (Arkhipov et al., 2004; Mikhalenko et al., 2005)- 2001_metals.pdf                                                    (Usubaliev, 2003)- 2003_GRG03-S1-EE_001.xlsx                                            (Mikhalenko et al., 2005; Kutuzov, 2005)- 2003_GRG03-S2-EE 001.xlsx                                            (Mikhalenko et al., 2005; Kutuzov, 2005)- 2003_pits.xlsx                                                    (Mikhalenko et al., 2005; Kutuzov, 2005)- 2003_temperature_density.xlsx                                        (Mikhalenko et al., 2005; Kutuzov, 2005)- 2003_temperature_logger_data.xls                                    (Mikhalenko et al., 2005; Kutuzov, 2005)- 2018_density_stratigraphy_field_and_PSI_by_centimeter.xlsx        (Machguth et al., 2024)- 2018_PSI_dating_20230517.xlsx                                        (Eichler et al., 2020; Machguth et al., 2024)

Detailed Information

1990_GRG_90_H1-BETA.xlsx: refers to Core 1 1990 (labelled H1 probably for "Hole 1"). Unknown to what the 1991 data refer, likely a repeat measurement.

1990_GRG_90_H1-CHM.xlsx: Chemistry Core 1 1990.

1990_GRG_90_H1-STRAT.xlsx: Stratigraphic information Core 1 1990

1990_GRG_90_H2-CHM.xlsx: Chemistry Core 2 1990

1990_GRG_90_H2-STRAT.xlsx: Stratigraphic information Core 2 1990

1990_H1-H2_2018_Grigoriev_MI-decadal.xlsx: This table we calculated from the 1990 tables as well as the 2018 data for the purpose of visualizing                                           decadal means in MIs (Fig. 7). Decadal dating of the 1990 cores was done based on the bomb horizon of 1963 (Thompson et al., 1993, 1997),                                            decadal picks from Thompson et al. (1993) and personal communication by Lonnie Thompson (email 19 June 2023).

2001_GRG_01_S1-EE.xlsx: 2001 core, stable water isotope ratios, firn temperatures, percentage of infiltration ice, stratigraphy

2003_GRG03-S1-EE_001.xlsx: 2003 51m and 22.6m cores, 51m core was drilled thermally, 22.6m core mechanically. For the latter similar data as for 2001

2003_GRG03-S2-EE 001.xlsx: 2003 21.3m core. Reduced amount of measured parameters compared to e.g. 2001 core. 

2003_pits.xlsx: Stratigraphy and density measured in a series of snow pits in 2003.

2003_temperature_density.xlsx: Density and temperature measured in 2003 22.6m core. Comparison of T_ice at 4440 m a.s.l. to 1962 core (Dikikh, 1965)

2003_temperature_logger_data.xls: Firn temperatures measured through a thermistor chain during 3 days in June 2003. Data from 14 June have been used for Fig. 5.

2018_density_stratigraphy_field_and_PSI_by_centimeter.xlsx: 2018 core stratigraphy and density. This is a somwhat outdated file which shows the data per centimetre.                                                            The file compares the two measurements of density (only the one from the laboratory was used in Machguth et al., 2024).                                                             Also contains visually observed dust layers (not shown in Machguth et al., 2024)

2018_PSI_dating_20230517.xlsx: Complete data from the analysis of the 2018 core.

Bibliography

Arkhipov, S. M., Mikhalenko, V. N., & Thompson, L. (1996). Struktura i stratigrafiya deyatel’nogo sloya lednika Grigor’eva na Tyan’-Shanye (Structure and stratigraphy of the active layer of the Griroriev glacier in the Tjan-Shan). Materialy Glyatsiologicheskikh Issledovaniy (Data of Glaciological Studies), 80, 68–83.

Arkhipov, S. M., Mikhalenko, V. N., Kunakhovich, M. G., Dikikh, A. N., and Nagornov, O. V.: Termicheskiy reshim, uslovija l’doobrazovanija i akkumulatsija na lednike Grigor’eva (Tyan’-Shan), v 1962–2001 gg. (Thermal regime, types of ice formation and accumulation on the Grigoriev glacier (Tien Shan), 1962–2001), Materialy Glyatsiologicheskikh Issledovaniy (Dataof Glaciological Studies), 96, 77–83, 2004.

Eichler, A., Kronenberg, M., Brütsch, S., Rüthi, M., Heule, M., Schwikowski, M., et al. (2020). Chernobyl horizon in a Central Asian ice core. Annual Report 2019 - Laboratory of Environmental Chemistry - PSI, 31.

Kutuzov, S. S.: Prostranstvennie izmenenija i stroenie lednikov vnutrennogo Tyan’-Shanya za poslednie 150 let (Spatial changes and structure of the glaciers of the inner Tien Shan over the last 150years), Master’s thesis, Lomonossov State University, Moskva, 2005.

Machguth, H., Eichler, A., Schwikowski, M., Brütsch, S., Mattea, E., Kutuzov, S., et al. (2024). Fifty years of firn evolution on Grigoriev ice cap, Tien Shan, Kyrgyzstan. The Cryosphere, 18(4), 1633–1646. https://doi.org/10.5194/tc-18-1633-2024

Mikhalenko, V. N., Kutuzov, S. S., Fayzrakhmanov, F. F., Nagornov, . B., Thompson, L. G., Kunakhovich, M. G., Arkhipov, S. M., Dikikh, A. N., and Usubaliev, R.: Sokrashhenie oledenenijaTyan’-Shanja v XIX – nachale XXI vv.: rezul’taty kernovoro burenija i izmerenija temperatury v skvazhinakh (Glacier recession in the Tien Shan from the XIX to the beginning of the XXI century:results from ice core drilling and borehole temperature measurements), Materialy Glyatsiologicheskikh Issledovaniy (Data of Glaciological Studies), 98, 175–182, 2005.

Thompson, L. G., Mosley-Thompson, E., Davis, M., Lin, P. N., Yao, T., Dyurgerov, M., & Dal, J. (1993). “Recent warming” ice core evidence from tropical ice cores with emphasis on Central Asia. Global Planet. Change, 7(1–3), 145–156. https://doi.org/10.1016/0921-8181(93)90046-Q

Thompson, L. G., Mikhalenko, V., Mosley-Thompson, E., Durgerov, M., Lin, P. N., Moskalevsky, M., et al. (1997). Ice core records of recent climatic variability: Grigoriev and It-Tish ice caps in Central Tien Shan, Central Asia. Materialy Glyatsiologicheskikh Issledovaniy (Data of Glaciological Studies), 81, 100–109.

Usubaliev, R. A. (2003). Khimitcheskoe zagryaznenie lednikov Tyan’-Shanya (na primere lednika Grigor’eva) (Chemical pollution of Tien Shan glaciers (on the example of Grigoriev Glacier)). Izvestija Natsional’noy Akademii Nauk Kirgizskoy Respubliki (News of the National Academy of Sciences of the Kyrgyz Republic), 4, 154–160.