東華大學圖書館 |

語系: 繁體中文

說明(常見問題)

回圖書館首頁

手機版館藏查詢

登入

回首頁

切換: 標籤 | MARC模式 | ISBD

FindBook

Google Book

Amazon

博客來

Using an Idealized Climate Model to Elucidate Physical Mechanisms and Improve Model Representation of Extratropical Cloud Feedbacks.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Using an Idealized Climate Model to Elucidate Physical Mechanisms and Improve Model Representation of Extratropical Cloud Feedbacks./
作者:	Frazer, Michelle Elizabeth.
面頁冊數:	1 online resource (157 pages)
附註:	Source: Dissertations Abstracts International, Volume: 83-05, Section: B.
Contained By:	Dissertations Abstracts International83-05B.
標題:	Atmospheric sciences. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28719137click for full text (PQDT)
ISBN:	9798460487240

Using an Idealized Climate Model to Elucidate Physical Mechanisms and Improve Model Representation of Extratropical Cloud Feedbacks.
Frazer, Michelle Elizabeth.

Using an Idealized Climate Model to Elucidate Physical Mechanisms and Improve Model Representation of Extratropical Cloud Feedbacks. - 1 online resource (157 pages)

Source: Dissertations Abstracts International, Volume: 83-05, Section: B.

Thesis (Ph.D.)--Princeton University, 2021.

Includes bibliographical references

Despite recent advances, the extratropical cloud feedback is at the heart of uncertainty and intermodel spread in climate sensitivity among comprehensive General Circulation Models (GCMs). Here, to shed light on the underlying mechanisms, we use an idealized GCM---the Held-Suarez dynamical core with the addition of passive water vapor and cloud tracers and full cloud microphysics---to cleanly decompose the effects of individual cloud processes.A set of process-level experiments are designed to elucidate the mechanisms of an increase in extratropical liquid water path (LWP) in mixed-phase clouds with warming: higher adiabatic cloud water content, weaker liquid-to-ice conversion through the Bergeron-Findeisen process, and faster melting of ice and snow to rain. Perturbed parameter experiments demonstrate a strong dependence of the LWP feedback on the climatological LWP and independence from the climatological susceptible ice and supercooled liquid fraction.To examine the broader physical controls of extratropical humidity and clouds, separate saturation adjustment and full cloud scheme controls are used to consider the strength of advection-condensation theory. It is found that sub-grid-scale relative humidity distribution assumed within the cloud macrophysics limits isentropic transport of tropical moisture to the polar troposphere. Also, within the model's explicit treatment of cloud microphysics, re-evaporation of hydrometeors moistens and increases clouds in the lower troposphere.To investigate the direct influence of dynamical changes on humidity and clouds, we explore the impacts of altered meridional temperature gradients. We show that predicted extratropical jet shifts with warming have little effect on shortwave cloud radiative effects because they mainly affect cloud fraction, not cloud thickness which is principally connected to absolute temperature change. Overall, the results substantiate the utility of such idealized models for elucidating cloud processes in a systematic manner and highlight key cloud processes to constrain.Additionally, a set of realistic experiments are designed in a comprehensive GCM to study geoengineering using stratospheric aerosols and compare efficacy and impacts of reflecting and absorbing aerosols (sulfate) versus only reflecting aerosols (calcite). We evaluate which regions are better or worse off with geoengineering in a 2xCO2 world in terms of various climate metrics and consider the policy implications.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2023

Mode of access: World Wide Web

ISBN: 9798460487240Subjects--Topical Terms:

3168354
Atmospheric sciences.
Subjects--Index Terms:

Climate changeIndex Terms--Genre/Form:

542853
Electronic books.

Using an Idealized Climate Model to Elucidate Physical Mechanisms and Improve Model Representation of Extratropical Cloud Feedbacks.
LDR:03908nmm a2200397K 4500 001 2354053
005 20230324111146.5
006 m o d
007 cr mn ---uuuuu
008 241011s2021 xx obm 000 0 eng d
020 $a 9798460487240
035 $a (MiAaPQ)AAI28719137
035 $a AAI28719137
040 $a MiAaPQ $b eng $c MiAaPQ $d NTU
100 1 $a Frazer, Michelle Elizabeth. $3 3694395
245 1 0 $a Using an Idealized Climate Model to Elucidate Physical Mechanisms and Improve Model Representation of Extratropical Cloud Feedbacks.
264 0 $c 2021
300 $a 1 online resource (157 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertations Abstracts International, Volume: 83-05, Section: B.
500 $a Advisor: Ming, Yi.
502 $a Thesis (Ph.D.)--Princeton University, 2021.
504 $a Includes bibliographical references
520 $a Despite recent advances, the extratropical cloud feedback is at the heart of uncertainty and intermodel spread in climate sensitivity among comprehensive General Circulation Models (GCMs). Here, to shed light on the underlying mechanisms, we use an idealized GCM---the Held-Suarez dynamical core with the addition of passive water vapor and cloud tracers and full cloud microphysics---to cleanly decompose the effects of individual cloud processes.A set of process-level experiments are designed to elucidate the mechanisms of an increase in extratropical liquid water path (LWP) in mixed-phase clouds with warming: higher adiabatic cloud water content, weaker liquid-to-ice conversion through the Bergeron-Findeisen process, and faster melting of ice and snow to rain. Perturbed parameter experiments demonstrate a strong dependence of the LWP feedback on the climatological LWP and independence from the climatological susceptible ice and supercooled liquid fraction.To examine the broader physical controls of extratropical humidity and clouds, separate saturation adjustment and full cloud scheme controls are used to consider the strength of advection-condensation theory. It is found that sub-grid-scale relative humidity distribution assumed within the cloud macrophysics limits isentropic transport of tropical moisture to the polar troposphere. Also, within the model's explicit treatment of cloud microphysics, re-evaporation of hydrometeors moistens and increases clouds in the lower troposphere.To investigate the direct influence of dynamical changes on humidity and clouds, we explore the impacts of altered meridional temperature gradients. We show that predicted extratropical jet shifts with warming have little effect on shortwave cloud radiative effects because they mainly affect cloud fraction, not cloud thickness which is principally connected to absolute temperature change. Overall, the results substantiate the utility of such idealized models for elucidating cloud processes in a systematic manner and highlight key cloud processes to constrain.Additionally, a set of realistic experiments are designed in a comprehensive GCM to study geoengineering using stratospheric aerosols and compare efficacy and impacts of reflecting and absorbing aerosols (sulfate) versus only reflecting aerosols (calcite). We evaluate which regions are better or worse off with geoengineering in a 2xCO2 world in terms of various climate metrics and consider the policy implications.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2023
538 $a Mode of access: World Wide Web
650 4 $a Atmospheric sciences. $3 3168354
650 4 $a Climate change. $2 bicssc $3 2079509
653 $a Climate change
653 $a Climate modeling
653 $a Cloud feedbacks
653 $a Clouds
653 $a Geoengineering
653 $a Idealized models
655 7 $a Electronic books. $2 lcsh $3 542853
690 $a 0725
690 $a 0404
710 2 $a ProQuest Information and Learning Co. $3 783688
710 2 $a Princeton University. $b Atmospheric and Oceanic Sciences. $3 3179531
773 0 $t Dissertations Abstracts International $g 83-05B.
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28719137 $z click for full text (PQDT)