Snoll, B, Ivanovic, RF orcid.org/0000-0002-7805-6018, Valdes, PJ et al. (2 more authors) (2022) Effect of orographic gravity wave drag on Northern Hemisphere climate in transient simulations of the last deglaciation. Climate Dynamics, 59 (7-8). ISSN 0930-7575
Abstract
Long transient simulations of the last deglaciation are increasingly being performed to identify the drivers of multiple rapid Earth system changes that occurred in this period. Such simulations frequently prescribe temporal variations in ice sheet properties, which can play an important role in controlling atmospheric and surface climate. To preserve a model’s standard performance in simulating climate, it is common to apply time dependent orographic variations, including parameterised sub-grid scale orographic variances, as anomalies from the pre-industrial state. This study investigates the causes of two abrupt climate change events in the Northern Hemisphere extratropics occurring between 16 and 14 thousand years ago in transient simulations of the last deglaciation from the Hadley Centre coupled general circulation model (HadCM3). One event is characterized by regional Northern Hemisphere changes comprising a centennial scale cooling of ~ 10 °C across Fennoscandia followed by rapid warming in less than 50 years as well as synchronous shifts in the Northern Annular Mode. The second event has comparable but temporally reversed characteristics. Sensitivity experiments reveal the climate anomalies are exclusively caused by artificially large values of orographic gravity wave drag, resulting from the combined use of the orographic anomaly method along with a unique inclusion of transient orography that linearly interpolates between timesteps in the ice sheet reconstruction. Palaeoclimate modelling groups should therefore carefully check the effects of their sub-grid scale orographic terms in transient palaeoclimate simulations with prescribed topographic evolution.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © The Author(s) 2022.This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. |
Keywords: | Transient simulations of the paleoclimate; Abrupt climate change; Orographic parameterisation; Transient orography; Orographic gravity wave drag; Atmospheric circulation |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) > Inst for Climate & Atmos Science (ICAS) (Leeds) |
Funding Information: | Funder Grant number NERC (Natural Environment Research Council) NE/M018199/1 Leverhulme Trust PLP-2018-278 EU - European Union 820829 RCUK (Research Councils UK) MR/S016961/1 NERC DTP NE/S007458/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 03 Mar 2022 14:35 |
Last Modified: | 19 Oct 2022 13:18 |
Status: | Published |
Publisher: | Springer Nature |
Identification Number: | 10.1007/s00382-022-06196-2 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:184107 |