Stratospheric wave predictability enhances surface forecasts over North America

Details

• Journal Title:
  Science Advances
• Personal Author:
  Ding, Xiuyuan ; Xiang, Baoqiang ; Chen, Gang ; Wang, Liping
• NOAA Program & Office:
  OAR (Oceanic and Atmospheric Research) ; GFDL (Geophysical Fluid Dynamics Laboratory)
• Description:
  Advances in subseasonal-to-seasonal (S2S) forecasting have broad socioeconomic benefits. Stratospheric variability has been identified as a major source of surface predictability on S2S timescales, yet its influence on forecasting North American cold extremes has not been fully understood. Here, using hindcasts from a coupled S2S forecast system, we identify a wave-1-like pattern among leading sources of predictability in the lower stratosphere during extended winters. This mode, characterized by strong stratospheric wave activity, improves second-week temperature prediction over North America by 15% (2 to 28%). It also increases the likelihood of North American cold extremes by 50%. Prediction skill for these extremes increases by 28% in forecasts conditioned on the wave-1-like stratospheric mode, across regions inhabited by over 69% of the Canadian population and over 30% of the U.S. population. These skill enhancements are attributed to the vertical wave coupling between the stratosphere and troposphere, distinct from the well-known downward influence of sudden stratospheric warmings (SSW). By conditioning forecasts on stratospheric states, our findings highlight strong stratospheric waves as windows of opportunity for skillful winter S2S predictions.
• Source:
  Science Advances, 12(38)
• DOI:
  https://doi.org/10.1126/sciadv.aee4171
• ISSN:
  2375-2548
• Format:
  PDF
• Publisher:
  American Association for the Advancement of Science (AAAS)
• Pubmed ID:
  42758849
• Pubmed Central ID:
  PMC13588185
• Document Type:
  Journal Article
• Funding:
  Grant no. NA23OAR4320198 ; Grant no. NA21OAR4310383 ; Grant no. NA22OAR4590217
• License:
  https://creativecommons.org/licenses/by-nc/4.0/
• Rights Information:
  CC BY-NC
• Compliance:
  Submitted
• Download URL:
  https://repository.library.noaa.gov/view/noaa/76513/noaa_76513_DS1.pdf
• File Type:
  [PDF - 3.87 MB]
• Collection(s):
  Office of Oceanic and Atmospheric Research (OAR)
• Main Document Checksum:
  urn:sha-512:a53f427ac1490bc39765d49b4323fe432aaf8e1f9eb16688c6b2cdd77f4adca18d95d2c13a29033d0f420d3166a22359087b6e21ebd53337107c4b63c880b8cd