Understanding Diverse Model Projections of Future Extreme El Niño

Stevenson, Samantha; Wittenberg, Andrew T.; Fasullo, John; Coats, Sloan; Otto-Bliesner, Bette

doi:10.1175/JCLI-D-19-0969.1

Advanced Search

Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

Advanced Search
Custom Query

All these words:

For very narrow results

This exact word or phrase:

When looking for a specific result

Any of these words:

Best used for discovery & interchangable words

None of these words:

Recommended to be used in conjunction with other fields

Language:

Dates

Publication Date Range:

to

Document Data

Title:

Document Type:

Library

Collection:

Series:

People

Author:

Clear All

Query Builder

Query box

Clear All

For additional assistance using the Custom Query please check out our Help Page

i

Understanding Diverse Model Projections of Future Extreme El Niño

2021
By Stevenson, Samantha ; Wittenberg, Andrew T. ; Fasullo, John ; ...
Source: Journal of Climate, 34(2), 449-464

[PDF-3.27 MB]

Details You May Also Like

Details:

Journal Title:

Journal of Climate
Personal Author:

Stevenson, Samantha ; Wittenberg, Andrew T. ; Fasullo, John ; Coats, Sloan ; Otto-Bliesner, Bette

Stevenson, Samantha ; Wittenberg, Andrew T. ; Fasullo, John ; Coats, Sloan ; Otto-Bliesner, Bette Less -
NOAA Program & Office:

OAR (Oceanic and Atmospheric Research) ; GFDL (Geophysical Fluid Dynamics Laboratory)

OAR (Oceanic and Atmospheric Research) ; GFDL (Geophysical Fluid Dynamics Laboratory) Less -
Description:

The majority of future projections in the Coupled Model Intercomparison Project (CMIP5) show more frequent exceedances of the 5 mm day−1 rainfall threshold in the eastern equatorial Pacific rainfall during El Niño, previously described in the literature as an increase in “extreme El Niño events”; however, these exceedance frequencies vary widely across models, and in some projections actually decrease. Here we combine single-model large ensemble simulations with phase 5 of the Coupled Model Intercomparison Project (CMIP5) to diagnose the mechanisms for these differences. The sensitivity of precipitation to local SST anomalies increases consistently across CMIP-class models, tending to amplify extreme El Niño occurrence; however, changes to the magnitude of ENSO-related SST variability can drastically influence the results, indicating that understanding changes to SST variability remains imperative. Future El Niño rainfall intensifies most in models with 1) larger historical cold SST biases in the central equatorial Pacific, which inhibit future increases in local convective cloud shading, enabling more local warming; and 2) smaller historical warm SST biases in the far eastern equatorial Pacific, which enhance future reductions in stratus cloud, enabling more local warming. These competing mechanisms complicate efforts to determine whether CMIP5 models under- or overestimate the future impacts of climate change on El Niño rainfall and its global impacts. However, the relation between future projections and historical biases suggests the possibility of using observable metrics as “emergent constraints” on future extreme El Niño, and a proof of concept using SSTA variance, precipitation sensitivity to SST, and regional SST trends is presented.
Keywords:

[+]

CMIP5 El Nino Sea Surface Temperature
Source:

Journal of Climate, 34(2), 449-464
DOI:

https://doi.org/10.1175/JCLI-D-19-0969.1
Document Type:

Journal Article
Rights Information:

Other
Compliance:

Submitted
Main Document Checksum:

[+]

urn:sha256:00bbde25f827471170504a5a7f240f13d8cacd43ca068d4a1dfbb67248f4433e
Download URL:

https://repository.library.noaa.gov/view/noaa/32255/noaa_32255_DS1.pdf
File Type:

No Additional Files

More +

Understanding Diverse Model Projections of Future Extreme El Niño

Details:

Supporting Files

You May Also Like