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Title: Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change

Abstract

Multiple lines of observational evidence indicate that the global climate has been getting warmer since the early 20th century. This warmer climate has led to a global mean sea level rise of about 18 cm during the 20th century, and over 6 cm for the first 15 years of the 21st century. Regionally the sea level rise is not uniform due in large part to internal climate variability. To better serve the community, the uncertainties of predicting/projecting regional sea level changes associated with internal climate variability need to be quantified. Previous research on this topic has used single-model large ensembles with perturbed atmospheric initial conditions (ICs). Here we compare uncertainties associated with perturbing ICs in just the atmosphere and just the ocean using a state-of-the-art coupled climate model. We find that by perturbing the oceanic ICs, the uncertainties in regional sea level changes increase compared to those with perturbed atmospheric ICs. In order for us to better assess the full spectrum of the impacts of such internal climate variability on regional and global sea level rise, approaches that involve perturbing both atmospheric and oceanic initial conditions are thus necessary.

Authors:
 [1];  [1];  [2];  [3];  [1]
  1. National Center for Atmospheric Research, Boulder, CO (United States). Climate and Global Dynamics Lab.
  2. Univ. of Hamburg (Germany). Center for Earth System Research and Sustainability (CEN)
  3. Univ. of Colorado, Boulder, CO (United States). Dept. of Atmospheric and Oceanic Sciences
Publication Date:
Research Org.:
Univ. Corp. for Atmospheric Research (UCAR); National Center for Atmospheric Research, Boulder, CO (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23); National Science Foundation (NSF)
OSTI Identifier:
1427767
Grant/Contract Number:
FC02-97ER62402
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Water (Basel)
Additional Journal Information:
Journal Name: Water (Basel); Journal Volume: 9; Journal Issue: 6; Journal ID: ISSN 2073-4441
Publisher:
MDPI
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; 97 MATHEMATICS AND COMPUTING; sea level rise; ensemble simulation; climate change

Citation Formats

Hu, Aixue, Meehl, Gerald, Stammer, Detlef, Han, Weiqing, and Strand, Warren. Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change. United States: N. p., 2017. Web. doi:10.3390/w9060401.
Hu, Aixue, Meehl, Gerald, Stammer, Detlef, Han, Weiqing, & Strand, Warren. Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change. United States. doi:10.3390/w9060401.
Hu, Aixue, Meehl, Gerald, Stammer, Detlef, Han, Weiqing, and Strand, Warren. Mon . "Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change". United States. doi:10.3390/w9060401. https://www.osti.gov/servlets/purl/1427767.
@article{osti_1427767,
title = {Role of Perturbing Ocean Initial Condition in Simulated Regional Sea Level Change},
author = {Hu, Aixue and Meehl, Gerald and Stammer, Detlef and Han, Weiqing and Strand, Warren},
abstractNote = {Multiple lines of observational evidence indicate that the global climate has been getting warmer since the early 20th century. This warmer climate has led to a global mean sea level rise of about 18 cm during the 20th century, and over 6 cm for the first 15 years of the 21st century. Regionally the sea level rise is not uniform due in large part to internal climate variability. To better serve the community, the uncertainties of predicting/projecting regional sea level changes associated with internal climate variability need to be quantified. Previous research on this topic has used single-model large ensembles with perturbed atmospheric initial conditions (ICs). Here we compare uncertainties associated with perturbing ICs in just the atmosphere and just the ocean using a state-of-the-art coupled climate model. We find that by perturbing the oceanic ICs, the uncertainties in regional sea level changes increase compared to those with perturbed atmospheric ICs. In order for us to better assess the full spectrum of the impacts of such internal climate variability on regional and global sea level rise, approaches that involve perturbing both atmospheric and oceanic initial conditions are thus necessary.},
doi = {10.3390/w9060401},
journal = {Water (Basel)},
number = 6,
volume = 9,
place = {United States},
year = {Mon Jun 05 00:00:00 EDT 2017},
month = {Mon Jun 05 00:00:00 EDT 2017}
}

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