Simulating Jupiter's weather layer. Part II: Passive ammonia and water cycles

Roland M.B. Young; Peter L. Read; Yixiong Wang

doi:10.1016/j.icarus.2018.12.002

Simulating Jupiter's weather layer. Part II: Passive ammonia and water cycles

Roland M.B. Young^*, Peter L. Read, Yixiong Wang

^*Corresponding author for this work

Physics

University of Oxford

Research output: Contribution to journal › Article › peer-review

14 Citations (Scopus)

Abstract

We examine the ammonia and water cycles in Jupiter's upper troposphere and lower stratosphere during spin-up of a multiple zonal jet global circulation using Oxford's Jupiter General Circulation Model. Jupiter's atmosphere is simulated at 512 × 256 horizontal resolution with 33 vertical levels between 0.01 and 18 bar, putting the lowest level well below the expected water cloud base. Simulations with and without a 5.7 Wm ⁻² interior heat source were run for 130000–150000 d to allow the deep atmosphere to come into radiative-convective-dynamical equilibrium, with variants on the interior heating case including varying the initial tracer distribution, particle condensate diameter, and cloud process timescales. The cloud scheme includes simple representations of the ammonia and water cycles. Ammonia vapour changes phase to ice, and reacts with hydrogen sulphide to produce ammonium hydrosulphide. Water changes phases between vapour, liquid, and ice depending on local environmental conditions, and all condensates sediment at their respective Stokes velocities. With interior heating, clouds of ammonia ice, ammonium hydrosulphide ice, and water ice form with cloud bases around 0.4 bar, 1.5 bar, and 3 bar, respectively. Without interior heating the ammonia cloud base forms in the same way, but the ammonium hydrosulphide and water clouds sediment to the bottom of the domain. The liquid water cloud is either absent or extremely sparse. Zonal structures form that correlate regions of strong latitudinal shear with regions of constant condensate concentration, implying that jets act as barriers to the mixing. Regions with locally high and low cloud concentrations also correlated with regions of upwelling and downwelling, respectively. Shortly after initialisation, the ammonia vapour distribution up to the cloud base resembles the enhanced concentration seen in Juno observations, due to strong meridional mean circulation at the equator. The resemblance decays rapidly over time, but suggests that at least some of the relevant physics is captured by the model. The comparison should improve with additional microphysics and better representation of the deep ammonia reservoir.

Original language	English
Pages (from-to)	253-268
Number of pages	16
Journal	Icarus
Volume	326
DOIs	https://doi.org/10.1016/j.icarus.2018.12.002
Publication status	Published - 1 Jul 2019

Bibliographical note

Funding Information:
Support for RMBY and PLR provided by UK STFC Grants ST/F003145/1, ST/I001948/1, and ST/K00106X/1. Support for PLR provided by UK STFC Grant ST/N00082X/1. Part of this work was completed during a visit to the Kavli Institute for Theoretical Physics at UC Santa Barbara. This work was supported in part by the US National Science Foundation under Grant No. NSF PHY-1125915. The authors would like to thank Jeremy Yates for his patience while we ran the simulations, and two anonymous reviewers whose extensive comments improved the paper significantly. Several figures used David Fanning's Coyote IDL Program Library. This work used the DiRAC Data Centric system at Durham University, operated by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (www.dirac.ac.uk). This equipment was funded by BIS National E-infrastructure capital grant ST/K00042X/1, STFC capital grant ST/K00087X/1, DiRAC Operations grant ST/K003267/1, and Durham University. DiRAC is part of the UK National E-Infrastructure. The authors acknowledge the use of the University of Oxford Advanced Research Computing (ARC) facility in carrying out this work. http://dx.doi.org/10.5281/zenodo.22558.

Data Availability Statement

Data from 154760–154860 d in Run A and 132900–133000 d in Run B can be obtained from the Oxford University Research Archive—Data (https://ora.ox.ac.uk) (Young et al., 2018a).

Keywords

Ammonia
Clouds
General Circulation Model
Jupiter
Water

Access to Document

10.1016/j.icarus.2018.12.002Licence: CC BY

Cite this

@article{4a9ff2acf7454402bc17d1f3fb1e93ce,

title = "Simulating Jupiter's weather layer. Part II: Passive ammonia and water cycles",

abstract = " We examine the ammonia and water cycles in Jupiter's upper troposphere and lower stratosphere during spin-up of a multiple zonal jet global circulation using Oxford's Jupiter General Circulation Model. Jupiter's atmosphere is simulated at 512 × 256 horizontal resolution with 33 vertical levels between 0.01 and 18 bar, putting the lowest level well below the expected water cloud base. Simulations with and without a 5.7 Wm −2 interior heat source were run for 130000–150000 d to allow the deep atmosphere to come into radiative-convective-dynamical equilibrium, with variants on the interior heating case including varying the initial tracer distribution, particle condensate diameter, and cloud process timescales. The cloud scheme includes simple representations of the ammonia and water cycles. Ammonia vapour changes phase to ice, and reacts with hydrogen sulphide to produce ammonium hydrosulphide. Water changes phases between vapour, liquid, and ice depending on local environmental conditions, and all condensates sediment at their respective Stokes velocities. With interior heating, clouds of ammonia ice, ammonium hydrosulphide ice, and water ice form with cloud bases around 0.4 bar, 1.5 bar, and 3 bar, respectively. Without interior heating the ammonia cloud base forms in the same way, but the ammonium hydrosulphide and water clouds sediment to the bottom of the domain. The liquid water cloud is either absent or extremely sparse. Zonal structures form that correlate regions of strong latitudinal shear with regions of constant condensate concentration, implying that jets act as barriers to the mixing. Regions with locally high and low cloud concentrations also correlated with regions of upwelling and downwelling, respectively. Shortly after initialisation, the ammonia vapour distribution up to the cloud base resembles the enhanced concentration seen in Juno observations, due to strong meridional mean circulation at the equator. The resemblance decays rapidly over time, but suggests that at least some of the relevant physics is captured by the model. The comparison should improve with additional microphysics and better representation of the deep ammonia reservoir.",

keywords = "Ammonia, Clouds, General Circulation Model, Jupiter, Water",

author = "Young, {Roland M.B.} and Read, {Peter L.} and Yixiong Wang",

note = "Funding Information: Support for RMBY and PLR provided by UK STFC Grants ST/F003145/1, ST/I001948/1, and ST/K00106X/1. Support for PLR provided by UK STFC Grant ST/N00082X/1. Part of this work was completed during a visit to the Kavli Institute for Theoretical Physics at UC Santa Barbara. This work was supported in part by the US National Science Foundation under Grant No. NSF PHY-1125915. The authors would like to thank Jeremy Yates for his patience while we ran the simulations, and two anonymous reviewers whose extensive comments improved the paper significantly. Several figures used David Fanning's Coyote IDL Program Library. This work used the DiRAC Data Centric system at Durham University, operated by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (www.dirac.ac.uk). This equipment was funded by BIS National E-infrastructure capital grant ST/K00042X/1, STFC capital grant ST/K00087X/1, DiRAC Operations grant ST/K003267/1, and Durham University. DiRAC is part of the UK National E-Infrastructure. The authors acknowledge the use of the University of Oxford Advanced Research Computing (ARC) facility in carrying out this work. http://dx.doi.org/10.5281/zenodo.22558. ",

year = "2019",

month = jul,

day = "1",

doi = "10.1016/j.icarus.2018.12.002",

language = "English",

volume = "326",

pages = "253--268",

journal = "Icarus",

issn = "0019-1035",

publisher = "Elsevier",

}

TY - JOUR

T1 - Simulating Jupiter's weather layer. Part II

T2 - Passive ammonia and water cycles

AU - Young, Roland M.B.

AU - Read, Peter L.

AU - Wang, Yixiong

N1 - Funding Information: Support for RMBY and PLR provided by UK STFC Grants ST/F003145/1, ST/I001948/1, and ST/K00106X/1. Support for PLR provided by UK STFC Grant ST/N00082X/1. Part of this work was completed during a visit to the Kavli Institute for Theoretical Physics at UC Santa Barbara. This work was supported in part by the US National Science Foundation under Grant No. NSF PHY-1125915. The authors would like to thank Jeremy Yates for his patience while we ran the simulations, and two anonymous reviewers whose extensive comments improved the paper significantly. Several figures used David Fanning's Coyote IDL Program Library. This work used the DiRAC Data Centric system at Durham University, operated by the Institute for Computational Cosmology on behalf of the STFC DiRAC HPC Facility (www.dirac.ac.uk). This equipment was funded by BIS National E-infrastructure capital grant ST/K00042X/1, STFC capital grant ST/K00087X/1, DiRAC Operations grant ST/K003267/1, and Durham University. DiRAC is part of the UK National E-Infrastructure. The authors acknowledge the use of the University of Oxford Advanced Research Computing (ARC) facility in carrying out this work. http://dx.doi.org/10.5281/zenodo.22558.

PY - 2019/7/1

Y1 - 2019/7/1

N2 - We examine the ammonia and water cycles in Jupiter's upper troposphere and lower stratosphere during spin-up of a multiple zonal jet global circulation using Oxford's Jupiter General Circulation Model. Jupiter's atmosphere is simulated at 512 × 256 horizontal resolution with 33 vertical levels between 0.01 and 18 bar, putting the lowest level well below the expected water cloud base. Simulations with and without a 5.7 Wm −2 interior heat source were run for 130000–150000 d to allow the deep atmosphere to come into radiative-convective-dynamical equilibrium, with variants on the interior heating case including varying the initial tracer distribution, particle condensate diameter, and cloud process timescales. The cloud scheme includes simple representations of the ammonia and water cycles. Ammonia vapour changes phase to ice, and reacts with hydrogen sulphide to produce ammonium hydrosulphide. Water changes phases between vapour, liquid, and ice depending on local environmental conditions, and all condensates sediment at their respective Stokes velocities. With interior heating, clouds of ammonia ice, ammonium hydrosulphide ice, and water ice form with cloud bases around 0.4 bar, 1.5 bar, and 3 bar, respectively. Without interior heating the ammonia cloud base forms in the same way, but the ammonium hydrosulphide and water clouds sediment to the bottom of the domain. The liquid water cloud is either absent or extremely sparse. Zonal structures form that correlate regions of strong latitudinal shear with regions of constant condensate concentration, implying that jets act as barriers to the mixing. Regions with locally high and low cloud concentrations also correlated with regions of upwelling and downwelling, respectively. Shortly after initialisation, the ammonia vapour distribution up to the cloud base resembles the enhanced concentration seen in Juno observations, due to strong meridional mean circulation at the equator. The resemblance decays rapidly over time, but suggests that at least some of the relevant physics is captured by the model. The comparison should improve with additional microphysics and better representation of the deep ammonia reservoir.

AB - We examine the ammonia and water cycles in Jupiter's upper troposphere and lower stratosphere during spin-up of a multiple zonal jet global circulation using Oxford's Jupiter General Circulation Model. Jupiter's atmosphere is simulated at 512 × 256 horizontal resolution with 33 vertical levels between 0.01 and 18 bar, putting the lowest level well below the expected water cloud base. Simulations with and without a 5.7 Wm −2 interior heat source were run for 130000–150000 d to allow the deep atmosphere to come into radiative-convective-dynamical equilibrium, with variants on the interior heating case including varying the initial tracer distribution, particle condensate diameter, and cloud process timescales. The cloud scheme includes simple representations of the ammonia and water cycles. Ammonia vapour changes phase to ice, and reacts with hydrogen sulphide to produce ammonium hydrosulphide. Water changes phases between vapour, liquid, and ice depending on local environmental conditions, and all condensates sediment at their respective Stokes velocities. With interior heating, clouds of ammonia ice, ammonium hydrosulphide ice, and water ice form with cloud bases around 0.4 bar, 1.5 bar, and 3 bar, respectively. Without interior heating the ammonia cloud base forms in the same way, but the ammonium hydrosulphide and water clouds sediment to the bottom of the domain. The liquid water cloud is either absent or extremely sparse. Zonal structures form that correlate regions of strong latitudinal shear with regions of constant condensate concentration, implying that jets act as barriers to the mixing. Regions with locally high and low cloud concentrations also correlated with regions of upwelling and downwelling, respectively. Shortly after initialisation, the ammonia vapour distribution up to the cloud base resembles the enhanced concentration seen in Juno observations, due to strong meridional mean circulation at the equator. The resemblance decays rapidly over time, but suggests that at least some of the relevant physics is captured by the model. The comparison should improve with additional microphysics and better representation of the deep ammonia reservoir.

KW - Ammonia

KW - Clouds

KW - General Circulation Model

KW - Jupiter

KW - Water

UR - http://www.scopus.com/inward/record.url?scp=85062232875&partnerID=8YFLogxK

U2 - 10.1016/j.icarus.2018.12.002

DO - 10.1016/j.icarus.2018.12.002

M3 - Article

AN - SCOPUS:85062232875

SN - 0019-1035

VL - 326

SP - 253

EP - 268

JO - Icarus

JF - Icarus

ER -

Simulating Jupiter's weather layer. Part II: Passive ammonia and water cycles

Abstract

Bibliographical note

Data Availability Statement

Keywords

Access to Document

Other files and links

Fingerprint

Cite this