Helle Astrid Kjær

Helle Astrid Kjær

Project Coordinator


  1. Published

    Supplementary material to "Bipolar volcanic synchronization of abrupt climate change in Greenland and Antarctic ice cores during the last glacial period"

    Svensson, Anders, Dahl-Jensen, Dorthe, Steffensen, Jørgen Peder, Blunier, Thomas, Rasmussen, Sune Olander, Vinther, Bo Møllesøe, Vallelonga, P., Capron, E., Gkinis, Vasileios, Cook, Eliza, Kjær, Helle Astrid, Muscheler, R., Kipfstuhl, S., Wilhelms, F., Stocker, T. F., Fischer, H., Adolphi, F., Erhardt, T., Sigl, M., Landais, A., Parrenin, F., Buizert, C., McConnell, J. R., Severi, M., Mulvaney, R. & Bigler, M., 6 Apr 2020, 32 p. Copernicus/EGU.

    Research output: Other contributionResearch

  2. Published

    On the occurrence of annual layers in Dome Fuji ice core early Holocene ice

    Svensson, Anders, Fujita, S., Bigler, M., Braun, M., Dallmayr, R., Gkinis, Vasileios, Goto-Azuma, K., Hirabayashi, M., Kawamura, K., Kipfstuhl, S., Kjær, Helle Astrid, Popp, T., Simonsen, M., Steffensen, Jørgen Peder, Vallelonga, P. & Vinther, Bo Møllesøe, 2015, In: Climate of the Past. 11, 9, p. 1127-1137

    Research output: Contribution to journalJournal articleResearchpeer-review

  3. Published

    Seasonality of halogen deposition in polar snow and ice

    Spolaor, A., Vallelonga, P., Gabrieli, J., Martma, T., Bjorkman, M. P., Isaksson, E., Cozzi, G., Turetta, C., Kjær, Helle Astrid, Curran, M. A. J., Moy, A. D., Schoenhardt, A., Blechschmidt, A. -., Burrows, J. P., Plane, J. M. C. & Barbante, C., 10 Jan 2014, In: Atmospheric Chemistry and Physics. 14, 18, p. 9613-9622

    Research output: Contribution to journalJournal articleResearchpeer-review

  4. Published

    Particle shape accounts for instrumental discrepancy in ice core dust size distributions

    Simonsen, M. F., Cremonesi, L., Baccolo, G., Bosch, S., Delmonte, B., Erhardt, T., Kjær, Helle Astrid, Potenza, M., Svensson, Anders & Vallelonga, P., 3 May 2018, In: Climate of the Past. 14, 5, p. 601-608

    Research output: Contribution to journalJournal articleResearchpeer-review

  5. Published

    East Greenland ice core dust record reveals timing of Greenland ice sheet advance and retreat.

    Simonsen, M. F., Baccolo, G., Blunier, Thomas, Borunda, A., Delmonte, B., Frei, R., Goldstein, S., Grinsted, Aslak, Kjær, Helle Astrid, Sowers, T. A., Svensson, Anders, Vinther, Bo Møllesøe, Vladimirova, D., Winckler, G., Winstrup, M. & Vallelonga, P. T., 3 Oct 2019, In: Nature Communications. 10, 8 p., 4494.

    Research output: Contribution to journalJournal articleResearchpeer-review

  6. Published

    Five thousand years of fire history in the high North Atlantic region: natural variability and ancient human forcing

    Segato, D., Villoslada Hidalgo, M. D. C., Edwards, R., Barbaro, E., Vallelonga, P., Kjær, Helle Astrid, Simonsen, M., Vinther, Bo Møllesøe, Maffezzoli, N., Zangrando, R., Turetta, C., Battistel, D., Vesteinsson, O., Barbante, C. & Spolaor, A., 20 Jul 2021, In: Climate of the Past. 17, 4, p. 1533-1545 13 p.

    Research output: Contribution to journalJournal articleResearchpeer-review

  7. Published

    Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene

    Schupbach, S., Fischer, H., Bigler, M., Erhardt, T., Gfeller, G., Leuenberger, D., Mini, O., Mulvaney, R., Abram, N. J., Fleet, L., Frey, M. M., Thomas, E., Svensson, Anders, Dahl-Jensen, Dorthe, Kettner, E., Kjær, Helle Astrid, Seierstad, I., Steffensen, Jørgen Peder, Rasmussen, Sune Olander, Vallelonga, P., Winstrup, M., Wegner, A., Twarloh, B., Wolff, K., Schmidt, K., Goto-Azuma, K., Kuramoto, T., Hirabayashi, M., Uetake, J., Zheng, J., Bourgeois, J., Fisher, D., Zhiheng, D., Xiao, C., Legrand, M., Spolaor, A., Gabrieli, J., Barbante, C., Kang, J. -., Hur, S. D., Hong, S. B., Hwang, H. J., Hong, S., Hansson, M., Iizuka, Y., Oyabu, I., Muscheler, R., Adolphi, F., Maselli, O. & McConnell, J., 16 Apr 2018, In: Nature Communications. 9, 1476.

    Research output: Contribution to journalJournal articleResearchpeer-review

  8. Published

    Rapid reductions and millennial-scale variability in Nordic Seas sea ice cover during abrupt glacial climate changes

    Sadatzki, H., Maffezzoli, N., Dokken, T. M., Simon, M. H., Berben, S. M. P., Fahl, K., Kjær, Helle Astrid, Spolaor, A., Stein, R., Vallelonga, P., Vinther, Bo Møllesøe & Jansen, E., 24 Nov 2020, In: Proceedings of the National Academy of Sciences of the United States of America. 117, 47, p. 29478-29486 9 p.

    Research output: Contribution to journalJournal articleResearchpeer-review

  9. Published

    A novel approach to process brittle ice for continuous flow analysis of stable water isotopes

    Pyne, R. L., Keller, E. D., Canessa, S., Bertler, N. A., Pyne, A. R., Pyne, A. R., Mandeno, D., Vallelonga, P. T., Semper, S., Kjær, Helle Astrid, Hutchison, E. & Baisden, W. T., 16 Mar 2018, In: Journal of Glaciology. 64, 243, p. 1-11

    Research output: Contribution to journalJournal articleResearchpeer-review

  10. Published

    Ice core evidence for a 20th century increase in surface mass balance in coastal Dronning Maud Land, East Antarctica

    Philippe, M., Tison, J., Fjosne, K., Hubbard, B., Kjær, Helle Astrid, Lenaerts, J. T. M., Drews, R., Sheldon, S. G., De Bondt, K., Claeys, P. & Pattyn, F., 2016, In: Cryosphere. 10, 5, p. 2501-2516 16 p.

    Research output: Contribution to journalJournal articleResearchpeer-review

ID: 33355865