EGU2020-20282
https://doi.org/10.5194/egusphere-egu2020-20282
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Switches of Holocene temperature-precipitation correlations in northern Hemisphere extra-tropics comparing proxy and model data

Ulrike Herzschuh1,2,3, Thomas Boehmer1, Raphael Herbert1, Thomas Laepple1, Richard Telford4, Xianyong Cao5, Anne Dallmeyer6, and Stefan Kruse1
Ulrike Herzschuh et al.
  • 1Alfred Wegener Institute, Research Unit Potsdam, Potsdam, Germany (ulrike.herzschuh@awi.de)
  • 2Institute of Environmental Sciences and Geography, University of Potsdam, Germany
  • 3Institute of Biochemistry and Biology, University of Potsdam, Germany
  • 4Department of Biological Sciences, University of Berger, Norway
  • 5Institute of Tibetan Plateau Resaerch, CAS, China
  • 6Max Planck Institute for Meteorology, Hamburg, Germany

Switches of temperature-precipitation correlation in northern Hemisphere extra-tropics

Future precipitation response to warming remains uncertain because climate models poorly reproduce observed changes of temperature-precipitation correlations. However, restricting model validations to the observational period may yield to misleading conclusions due to the complexity of the involved processes. Our analyses of Holocene proxy-based temperature-precipitation correlations from 1500 northern Hemisphere extratropic pollen records portrayed significant latitudinal dependance, temporal changes from the early to late Holocene as well as differences between short and long time-scales. These observed variations were found to be mostly consistent with patterns simulated by Holocene transient climate simulations. Our results suggest that the strength of positive temperature-precipitation correlations in high-latitudes is sensitive to the background temperature while monsoonal subtropics reflect spatial shifts of circulation systems; and correlation sign switches in mid-latitudes relate to changes of westerlies strength. We conclude that regional and continental climate change on land is more complex than the expected “wetter climate in a warmer world” assumption which holds well at the global scale. On the other hand, long-term projections of precipitation may be better than previously thought as major processes seem to be already implemented correctly in general circulation models.

How to cite: Herzschuh, U., Boehmer, T., Herbert, R., Laepple, T., Telford, R., Cao, X., Dallmeyer, A., and Kruse, S.: Switches of Holocene temperature-precipitation correlations in northern Hemisphere extra-tropics comparing proxy and model data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20282, https://doi.org/10.5194/egusphere-egu2020-20282, 2020