{"action":"created","issue":{"url":"https://api.github.com/repos/StrikeNP/trac_test/issues/182","repository_url":"https://api.github.com/repos/StrikeNP/trac_test","labels_url":"https://api.github.com/repos/StrikeNP/trac_test/issues/182/labels{/name}","comments_url":"https://api.github.com/repos/StrikeNP/trac_test/issues/182/comments","events_url":"https://api.github.com/repos/StrikeNP/trac_test/issues/182/events","html_url":"https://github.com/StrikeNP/trac_test/issues/182","id":332146357,"node_id":"MDU6SXNzdWUzMzIxNDYzNTc=","number":182,"title":"Upwind differencing for wpxp_ta terms (Trac #182)","user":{"login":"StrikeNP","id":2577059,"node_id":"MDQ6VXNlcjI1NzcwNTk=","avatar_url":"https://avatars0.githubusercontent.com/u/2577059?v=4","gravatar_id":"","url":"https://api.github.com/users/StrikeNP","html_url":"https://github.com/StrikeNP","followers_url":"https://api.github.com/users/StrikeNP/followers","following_url":"https://api.github.com/users/StrikeNP/following{/other_user}","gists_url":"https://api.github.com/users/StrikeNP/gists{/gist_id}","starred_url":"https://api.github.com/users/StrikeNP/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/StrikeNP/subscriptions","organizations_url":"https://api.github.com/users/StrikeNP/orgs","repos_url":"https://api.github.com/users/StrikeNP/repos","events_url":"https://api.github.com/users/StrikeNP/events{/privacy}","received_events_url":"https://api.github.com/users/StrikeNP/received_events","type":"User","site_admin":false},"labels":[{"id":963997231,"node_id":"MDU6TGFiZWw5NjM5OTcyMzE=","url":"https://api.github.com/repos/StrikeNP/trac_test/labels/Migrated%20from%20Trac","name":"Migrated from Trac","color":"FFFFFF","default":false},{"id":963997516,"node_id":"MDU6TGFiZWw5NjM5OTc1MTY=","url":"https://api.github.com/repos/StrikeNP/trac_test/labels/clubb_src","name":"clubb_src","color":"FFFFFF","default":false},{"id":963997501,"node_id":"MDU6TGFiZWw5NjM5OTc1MDE=","url":"https://api.github.com/repos/StrikeNP/trac_test/labels/dschanen@uwm.edu","name":"dschanen@uwm.edu","color":"FFFFFF","default":false},{"id":963997043,"node_id":"MDU6TGFiZWw5NjM5OTcwNDM=","url":"https://api.github.com/repos/StrikeNP/trac_test/labels/enhancement","name":"enhancement","color":"a2eeef","default":true}],"state":"open","locked":false,"assignee":null,"assignees":[],"milestone":{"url":"https://api.github.com/repos/StrikeNP/trac_test/milestones/7","html_url":"https://github.com/StrikeNP/trac_test/milestone/7","labels_url":"https://api.github.com/repos/StrikeNP/trac_test/milestones/7/labels","id":3423174,"node_id":"MDk6TWlsZXN0b25lMzQyMzE3NA==","number":7,"title":"Improve CLUBB's accuracy at coarse vertical grid spacing","description":null,"creator":{"login":"StrikeNP","id":2577059,"node_id":"MDQ6VXNlcjI1NzcwNTk=","avatar_url":"https://avatars0.githubusercontent.com/u/2577059?v=4","gravatar_id":"","url":"https://api.github.com/users/StrikeNP","html_url":"https://github.com/StrikeNP","followers_url":"https://api.github.com/users/StrikeNP/followers","following_url":"https://api.github.com/users/StrikeNP/following{/other_user}","gists_url":"https://api.github.com/users/StrikeNP/gists{/gist_id}","starred_url":"https://api.github.com/users/StrikeNP/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/StrikeNP/subscriptions","organizations_url":"https://api.github.com/users/StrikeNP/orgs","repos_url":"https://api.github.com/users/StrikeNP/repos","events_url":"https://api.github.com/users/StrikeNP/events{/privacy}","received_events_url":"https://api.github.com/users/StrikeNP/received_events","type":"User","site_admin":false},"open_issues":30,"closed_issues":6,"state":"open","created_at":"2018-06-13T20:02:02Z","updated_at":"2018-06-14T08:11:06Z","due_on":null,"closed_at":null},"comments":8,"created_at":"2018-06-13T20:13:28Z","updated_at":"2018-06-14T09:42:43Z","closed_at":null,"author_association":"OWNER","body":"Ryan Senkbeil and I are trying to simulate an overcast cloud layer, cloud_feedbacks s12 case (see https://github.com/larson-group/clubb/issues/7 and the following figure: \n\nhttp://carson.math.uwm.edu/trac/clubb/attachment/ticket/7/wprtp_1min.png ).\n\nWe obtain good results at high vertical resolution (white line).  However, at coarse resolution, some undesirable oscillations (green line) develop that indirectly kill the cloud.  The undesirable oscillations appear to be caused by the turbulent advection term wprtp_ta:  \n\nd (wprtp) / dt = - d( wp2rtp ) / dz + . . .  \n\nBill Skamarock suggests that perhaps we could fix this problem by using implicit upwind differencing for this term (and this term alone).  \n\nwp2rtp = a1 * (wp3/wp2) *wprtp is given by eqn 27 in http://www.larson-group.com/clubb_site/protected/memberfiles/clubb_documentation/hoceqns.pdf.  In this equation a1 > 0, and the ratio wp3/wp2 could be regarded as a “wind” that will give the sign of “advection” for wprtp.  Bill also would be interested to know about the magnitude of the effective Courant number for the term, i.e. a1*(wp3/wp2)*dt/dz. \n\nAttachments:\n\n[courant_number.png](https://github.com/larson-group/trac_attachment_archive/blob/master/clubb/courant_number.png)\n[cloud_feedback_s12_wprtp_ta.png](https://github.com/larson-group/trac_attachment_archive/blob/master/clubb/cloud_feedback_s12_wprtp_ta.png)\n[cloud_feedback_s12_wpthlp_ta.png](https://github.com/larson-group/trac_attachment_archive/blob/master/clubb/cloud_feedback_s12_wpthlp_ta.png)\n[wprtp_ta_upwind_flipped.png](https://github.com/larson-group/trac_attachment_archive/blob/master/clubb/wprtp_ta_upwind_flipped.png)\n\nMigrated from http://carson.math.uwm.edu/trac/clubb/ticket/182\n```json\n{\n    \"status\": \"closed\", \n    \"changetime\": \"2010-12-29T21:03:32\", \n    \"description\": \"Ryan Senkbeil and I are trying to simulate an overcast cloud layer, cloud_feedbacks s12 case (see comment:62:ticket:7 and the following figure: \\n\\nhttp://carson.math.uwm.edu/trac/clubb/attachment/ticket/7/wprtp_1min.png ).\\n\\nWe obtain good results at high vertical resolution (white line).  However, at coarse resolution, some undesirable oscillations (green line) develop that indirectly kill the cloud.  The undesirable oscillations appear to be caused by the turbulent advection term wprtp_ta:  \\n\\nd (wprtp) / dt = - d( wp2rtp ) / dz + . . .  \\n\\nBill Skamarock suggests that perhaps we could fix this problem by using implicit upwind differencing for this term (and this term alone).  \\n\\nwp2rtp = a1 * (wp3/wp2) *wprtp is given by eqn 27 in http://www.larson-group.com/clubb_site/protected/memberfiles/clubb_documentation/hoceqns.pdf.  In this equation a1 > 0, and the ratio wp3/wp2 could be regarded as a \\u201cwind\\u201d that will give the sign of \\u201cadvection\\u201d for wprtp.  Bill also would be interested to know about the magnitude of the effective Courant number for the term, i.e. a1*(wp3/wp2)*dt/dz. \", \n    \"reporter\": \"vlarson@uwm.edu\", \n    \"cc\": \"bmg2@uwm.edu, ldgrant@uwm.edu\", \n    \"resolution\": \"Verified by V. Larson\", \n    \"_ts\": \"1293656612000000\", \n    \"component\": \"clubb_src\", \n    \"summary\": \"Upwind differencing for wpxp_ta terms\", \n    \"priority\": \"major\", \n    \"keywords\": \"\", \n    \"time\": \"2009-08-11T21:15:19\", \n    \"milestone\": \"Improve CLUBB's accuracy at coarse vertical grid spacing\", \n    \"owner\": \"dschanen@uwm.edu\", \n    \"type\": \"enhancement\"\n}\n```\n"},"comment":{"url":"https://api.github.com/repos/StrikeNP/trac_test/issues/comments/397236082","html_url":"https://github.com/StrikeNP/trac_test/issues/182#issuecomment-397236082","issue_url":"https://api.github.com/repos/StrikeNP/trac_test/issues/182","id":397236082,"node_id":"MDEyOklzc3VlQ29tbWVudDM5NzIzNjA4Mg==","user":{"login":"StrikeNP","id":2577059,"node_id":"MDQ6VXNlcjI1NzcwNTk=","avatar_url":"https://avatars0.githubusercontent.com/u/2577059?v=4","gravatar_id":"","url":"https://api.github.com/users/StrikeNP","html_url":"https://github.com/StrikeNP","followers_url":"https://api.github.com/users/StrikeNP/followers","following_url":"https://api.github.com/users/StrikeNP/following{/other_user}","gists_url":"https://api.github.com/users/StrikeNP/gists{/gist_id}","starred_url":"https://api.github.com/users/StrikeNP/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/StrikeNP/subscriptions","organizations_url":"https://api.github.com/users/StrikeNP/orgs","repos_url":"https://api.github.com/users/StrikeNP/repos","events_url":"https://api.github.com/users/StrikeNP/events{/privacy}","received_events_url":"https://api.github.com/users/StrikeNP/received_events","type":"User","site_admin":false},"created_at":"2018-06-14T09:42:43Z","updated_at":"2018-06-14T09:42:43Z","author_association":"OWNER","body":"**Trac update on 2010/01/19 at 19:34**\n**vlarson@uwm.edu commented:**\n\nReplying to [comment:4 senkbeil@…]:\n> I attached two screenshots above comparing a run of Cloud Feedback S12 with standard repository settings (128 level grid).\n> \n> I verified that wprtp_ta and wpthlp_ta matched that of a fresh repository checkout of CLUBB.\n\nConfusingly, these plots seem to indicate that the upwind differencing contain spurious extrema and is noisier than our standard differencing.  There is an error in the discretization (we should use dzt intead of dzm, comment:5), that we should fix first.  But I doubt that fixing that will make the upwind solution smoother.  \n\nWe could re-run with the new discretization in non-interactive mode.  Then we could re-run with the new discretization interacting with the rest of the code.  Perhaps the upwind solution is noisy because it is being forced by the solution from the standard discretization.\n\n"}}
{"actor":{"display_login":"StrikeNP"}}