Trend in atmospheric angular momentum in a transient climate change simulation with greenhouse gas and aerosol frocing

Huei-Ping Huang, K. M. Weickmann

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

The authors investigate the change of atmospheric angular momentum (AAM) in long, transient, coupled atmosphere-ocean model simulations with increasing atmospheric greenhouse gas concentration and sulfate aerosol loading. A significant increase of global AAM, on the order of 4 × 10 25 kg m 2 s -1 for 3 × CO 2-1 × CO 2, was simulated by the Canadian Centre for Climate Modelling and Analysis (CCCma) coupled model. The increase was mainly contributed by the relative component of total AAM in the form of an acceleration of zonal mean zonal wind in the tropical-subtropical upper troposphere. Thus, under strong global warming, a super-rotational state emerged in the tropical upper troposphere. The trend in zonal mean zonal wind in the meridional plane was characterized by 1) a tropical-subtropical pattern with two maxima near 30° in the upper troposphere, and 2) a tripole pattern in the Southern Hemisphere extending through the entire troposphere and having a positive maximum at 60°S. The implication of the projected increase of global AAM for future changes of the length of day is discussed. The CCCma coupled global warming simulation, like many previous studies, shows a significant increase of tropical SST and includes a zonally asymmetric component that resembles El Niño SST anomalies. In the CCCma transient simulations, even though the tropical SST and global AAM both increased nonlinearly with time, the ratio of their time increments ΔAAM/ΔSST remained approximately constant at about 0.9 × 10 25 kg m 2 s -1 (°C) -1. This number is close to its counterpart for the observed global AAM response to El Niño. It is suggested that this ratio may be useful as an index for intercomparisons of different coupled model simulations.

Original languageEnglish (US)
Pages (from-to)1525-1534
Number of pages10
JournalJournal of Climate
Volume14
Issue number7
StatePublished - Apr 1 2001
Externally publishedYes

Fingerprint

angular momentum
greenhouse gas
aerosol
climate change
troposphere
sea surface temperature
simulation
climate modeling
zonal wind
global warming
atmospheric gas
trend
Southern Hemisphere
sulfate
anomaly
atmosphere
ocean
analysis

ASJC Scopus subject areas

  • Atmospheric Science

Cite this

Trend in atmospheric angular momentum in a transient climate change simulation with greenhouse gas and aerosol frocing. / Huang, Huei-Ping; Weickmann, K. M.

In: Journal of Climate, Vol. 14, No. 7, 01.04.2001, p. 1525-1534.

Research output: Contribution to journalArticle

@article{75caca285e664a9db1d05a9320e8b5f9,
title = "Trend in atmospheric angular momentum in a transient climate change simulation with greenhouse gas and aerosol frocing",
abstract = "The authors investigate the change of atmospheric angular momentum (AAM) in long, transient, coupled atmosphere-ocean model simulations with increasing atmospheric greenhouse gas concentration and sulfate aerosol loading. A significant increase of global AAM, on the order of 4 × 10 25 kg m 2 s -1 for 3 × CO 2-1 × CO 2, was simulated by the Canadian Centre for Climate Modelling and Analysis (CCCma) coupled model. The increase was mainly contributed by the relative component of total AAM in the form of an acceleration of zonal mean zonal wind in the tropical-subtropical upper troposphere. Thus, under strong global warming, a super-rotational state emerged in the tropical upper troposphere. The trend in zonal mean zonal wind in the meridional plane was characterized by 1) a tropical-subtropical pattern with two maxima near 30° in the upper troposphere, and 2) a tripole pattern in the Southern Hemisphere extending through the entire troposphere and having a positive maximum at 60°S. The implication of the projected increase of global AAM for future changes of the length of day is discussed. The CCCma coupled global warming simulation, like many previous studies, shows a significant increase of tropical SST and includes a zonally asymmetric component that resembles El Ni{\~n}o SST anomalies. In the CCCma transient simulations, even though the tropical SST and global AAM both increased nonlinearly with time, the ratio of their time increments ΔAAM/ΔSST remained approximately constant at about 0.9 × 10 25 kg m 2 s -1 (°C) -1. This number is close to its counterpart for the observed global AAM response to El Ni{\~n}o. It is suggested that this ratio may be useful as an index for intercomparisons of different coupled model simulations.",
author = "Huei-Ping Huang and Weickmann, {K. M.}",
year = "2001",
month = "4",
day = "1",
language = "English (US)",
volume = "14",
pages = "1525--1534",
journal = "Journal of Climate",
issn = "0894-8755",
publisher = "American Meteorological Society",
number = "7",

}

TY - JOUR

T1 - Trend in atmospheric angular momentum in a transient climate change simulation with greenhouse gas and aerosol frocing

AU - Huang, Huei-Ping

AU - Weickmann, K. M.

PY - 2001/4/1

Y1 - 2001/4/1

N2 - The authors investigate the change of atmospheric angular momentum (AAM) in long, transient, coupled atmosphere-ocean model simulations with increasing atmospheric greenhouse gas concentration and sulfate aerosol loading. A significant increase of global AAM, on the order of 4 × 10 25 kg m 2 s -1 for 3 × CO 2-1 × CO 2, was simulated by the Canadian Centre for Climate Modelling and Analysis (CCCma) coupled model. The increase was mainly contributed by the relative component of total AAM in the form of an acceleration of zonal mean zonal wind in the tropical-subtropical upper troposphere. Thus, under strong global warming, a super-rotational state emerged in the tropical upper troposphere. The trend in zonal mean zonal wind in the meridional plane was characterized by 1) a tropical-subtropical pattern with two maxima near 30° in the upper troposphere, and 2) a tripole pattern in the Southern Hemisphere extending through the entire troposphere and having a positive maximum at 60°S. The implication of the projected increase of global AAM for future changes of the length of day is discussed. The CCCma coupled global warming simulation, like many previous studies, shows a significant increase of tropical SST and includes a zonally asymmetric component that resembles El Niño SST anomalies. In the CCCma transient simulations, even though the tropical SST and global AAM both increased nonlinearly with time, the ratio of their time increments ΔAAM/ΔSST remained approximately constant at about 0.9 × 10 25 kg m 2 s -1 (°C) -1. This number is close to its counterpart for the observed global AAM response to El Niño. It is suggested that this ratio may be useful as an index for intercomparisons of different coupled model simulations.

AB - The authors investigate the change of atmospheric angular momentum (AAM) in long, transient, coupled atmosphere-ocean model simulations with increasing atmospheric greenhouse gas concentration and sulfate aerosol loading. A significant increase of global AAM, on the order of 4 × 10 25 kg m 2 s -1 for 3 × CO 2-1 × CO 2, was simulated by the Canadian Centre for Climate Modelling and Analysis (CCCma) coupled model. The increase was mainly contributed by the relative component of total AAM in the form of an acceleration of zonal mean zonal wind in the tropical-subtropical upper troposphere. Thus, under strong global warming, a super-rotational state emerged in the tropical upper troposphere. The trend in zonal mean zonal wind in the meridional plane was characterized by 1) a tropical-subtropical pattern with two maxima near 30° in the upper troposphere, and 2) a tripole pattern in the Southern Hemisphere extending through the entire troposphere and having a positive maximum at 60°S. The implication of the projected increase of global AAM for future changes of the length of day is discussed. The CCCma coupled global warming simulation, like many previous studies, shows a significant increase of tropical SST and includes a zonally asymmetric component that resembles El Niño SST anomalies. In the CCCma transient simulations, even though the tropical SST and global AAM both increased nonlinearly with time, the ratio of their time increments ΔAAM/ΔSST remained approximately constant at about 0.9 × 10 25 kg m 2 s -1 (°C) -1. This number is close to its counterpart for the observed global AAM response to El Niño. It is suggested that this ratio may be useful as an index for intercomparisons of different coupled model simulations.

UR - http://www.scopus.com/inward/record.url?scp=0035297901&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035297901&partnerID=8YFLogxK

M3 - Article

VL - 14

SP - 1525

EP - 1534

JO - Journal of Climate

JF - Journal of Climate

SN - 0894-8755

IS - 7

ER -