Mesoscale waves
By Glenn on 2018-02-07 UT
Observations of waves in Jupiter's atmosphere have been made by several spacecraft, starting with Voyager, and this has continued with recent observations by the Hubble Space Telescope in the visible and Very Large Telescope observations at 5 microns. The JunoCam instrument has identified waves structures on a finer scale (smaller than 170 km) that have ever been observed previously. One of these is apparent in the PJ7 observations of the northern edge of the Great Red Spot. But others are apparent elsewhere, primarily near the equator, on other perijoves. This thread will mirror work by the team leading to a published paper summarizing these results with a planned submission in early summer of 2018.
20 Comments
2020 January 2. The submission to JGR needed to be modified in order to acount for two reference to article that were "in press" and "submitted". I provided a DOI for the article by Ashwin Braude et all that was in press, and I provided a copy of the submitted version of the article by Michael H. Wong. The submission was then accepted and transferred to the editor.
The following is a Zipped version of the Supplemental Informaion file, accompanying the primary article, just submitted to the Journal of Geophysical Research for the special Juno issue.
-Glenn Orton, 2019 Decmeber 31
The following is a Zipped version of the primary manuscript just submitted to the Journal of Geophysical Research for the special Juno issue.
This is the 2019 December 26 version of the Supplemental Information file for the article on fine-scale waves. All corrections have been made and the file is ready to submit as an ancillary file to the primary article for the special issue of the Journal of Geophysical Research on latest results from the Juno mission.
Here is an update of the Supplemental Information file from November 27, 2019.
We are preparing a manuscript for a publication in a special issue of the Journal of Geophysical Research - Planets (published by the American Geophysical Union): A Survey of Small-Scale Waves and Wave-Like Phenomena in Jupiter's Atmosphere Detected by JunoCam. I'm the lead author, and we're racing to get this written by the nominal deadline of November 30. Attached is the November 17 version of the Supplemental Information file that will accompany the main article, which we wrote first because it includes excepts of images (in cylinrical-map form) of anywhere we detected candidates for small-scale waves and wave-like phenomena, a sub-set of which we will extract for the main article. This will be updaed to include tables of measured properties.
I 'made a presentation on what we've done on mesoscale waves to date at the 2018 American Astronomical Society's Division for Planetary Sciences meeting (on their 50th anniversary). It was picked up as a press release by the AAS and the DPS press officers, and it's available here: https://www.jpl.nasa.gov/news/news.php?feature=7264. There was a press conference in which I participated that was Webcast and recorded; it's available here, with my contribution (the second of three speakers) starting around the 12:00 mark: https://aas.org/medi…/archived-aas-press-conference-webcasts. My abbreviated presentation power-point for the press conference can be accessed here: https://aas.org/files/resources/dps50_glenn_orton.pdf?fbclid=IwAR0BpROHwyoSvpQSBM1WdtyTLOE66fkY7bT7g9avh6czyCDGtEyupTE4tHI. I also attach my full formal presentation.
My goal is to get this submitted to publication by early in 2019.
Glenn Orton
A rendition run of high-pass filtered maps of the most close-up RGB images for PJs 1 to 13 is completed, and according links are added to this website:
http://junocam.pictures/gerald/topics/mesoscale_waves/cyl_maps_180px/index.html
The high-pass filtering is context-sensitive and adjusts for the local standard deviation of according illumination-adjusted maps. This maintains a similar local contrast across the maps.
Some of the PJ12 maps have been cropped into stripes in order to reduce rendition time.
Several of the maps are provided as a less processed version, too, especially when rendered for the first time. The maps are rendered approximately in planetocentrical cylindrical equidistant format with north to the right, and with a resolution of about 180 pixels per degree. Residual projection inaccuracies are possible. Links to the processing parameters, especially regarding the longitude and latitude ranges, are planned to be provided later.
This is a poster to be presented at the Asia-Oceana Geosciences Society (AOGS) 2018 meeting that summarizes much of our work in the last few months on the identification and characterization of waves and wave-like features in Juno's Perijoves 1 and 3-13. We didn't have room to include the high-pass processing on images that has been done in order to look for very faint indications of waves and wave-like features, so this survey is more-or-less complete only insofar as waves are easily recognizable. For many images, we also have quantitative measurements of the latitude and longitude bounds of the wave, together with measurements of the distance between the waves (wavelengths) in km.
A correction on the reference, Simon et al. (2015). This should be:
Simon, A. A., L. Li, D. C. Reuter 2015. Small-scale waves on Jupiter: A reanalysis of New Horizons, Voyager and Galileo data. Geophys. Res. Letters 42, 2612-2618, DOI: 10.1002/2015GL063433
Some crop of an enhanced cylindrical map PJ12, #90. A link to a larger map is provided in the comment below.
The maps are averges of two processed maps, one map gamma stretched after illumination adustment, the other map filtered by a context-sensitive hipass filter that adjusts for local contrast.
PJ12, #90, cylindrical maps, strongly enhanced, 90 pixels per planetocentrical degree, and links to renditions with 360 pixels per degree:
http://junocam.pictures/gerald/uploads/20180522/JNCE_2018091_12C00090_V01_avrg_Hipass00_taylorIncEm_annot02_crop1_N_up.png
http://junocam.pictures/gerald/uploads/20180522/JNCE_2018091_12C00090_V01_avrg_Hipass00_taylorIncEm_N_up.png
Some more subtle wave train candidates are easily overlooked in the context of the very distinct ones.
Note, that I've been off by 180 degrees longitude with respect to System III.
Here is a version of image PJ12_90 that has been processed and filtered to reveal a lot of mesoscale waves, many of which appear rather subtle if no processing is applied.
Because of the wide field of view the image has some perspective foreshortening. Therefore an approximately true color/contrast version with a latitude/longitude grid is included. Latitude is planetographic.
A global context render is also included. It is based on Marco Vedovato's map that includes images from March 29-31, 2018.
Attached is an annotated crop of a hipassed cylindrical map rendered with 360 pixels per planetocentric degrees. Annotations indicate what I'm inclined to see. A mostly smoother area north of 22°N contrasts the rippled area south of 22°N. The wavelenghts of the ripples seem vary around 100'' to 160'' longitude.
Longitudes to be corrected by 180 degrees L3.
There appear to be subtle, but widespread waves in PJ12, #087. This is remarkable, since they are about 20 degrees north. planetocentric. The attached image is a crop of an enhanced reprojection, not a map.
I'm having trouble seeing the waves in this image, unless I'm missing them because the whole field is filled with them. - Glenn
I've added links to PJ-08, and PJ-09 maps in the site linked to in the previous comment.
In PJ-09, image #088, there is a narrow, but distinct mesocsale wave train, a little south of the equator.
On the following site, I've provided cylindrical maps of PJ11 RGB images with a resolution of 180 pixels oer planetocentric degree, and from 15 degrees south to 15 degrees north.
http://junocam.pictures/gerald/topics/mesoscale_waves/cyl_maps_180px/
I'll add similar maps of other perijoves to the same site as time allows.
I tried to animate enhanced crops of the PJ11 maps, but with the residual distortions, there is significant wobbling making it difficult to see actual motion of the waves.