{"id":613,"date":"2015-07-31T11:19:24","date_gmt":"2015-07-31T11:19:24","guid":{"rendered":"http:\/\/www.nwpsaf.eu\/site\/?page_id=613"},"modified":"2017-06-05T10:58:09","modified_gmt":"2017-06-05T10:58:09","slug":"1d-var-ecmwf-package","status":"publish","type":"page","link":"https:\/\/nwp-saf.eumetsat.int\/site\/software\/1d-var\/previous-packages\/1d-var-ecmwf-package\/","title":{"rendered":"1D Var ECMWF package"},"content":{"rendered":"<div>\n<h2>ECMWF 1D-Var<\/h2>\n<\/div>\n<div id=\"mainContent\">\n<p>The ECMWF 1D-Var package is a generalised minimisation code applicable to a wide range of inversion problems for satellite data, and it is not set up to handle any particular instrument. It makes use of the M1QN3 software from INRIA (quasi-Newton method) and preconditions the state vector with the eigenvectors of the background error covariance. The code is in Fortran and documented. It cannot be treated as a \u2018black box\u2019 as various additional modules have to be interfaced to the ECMWF 1D-Var package before it will work. The user must define a control variable and interface an appropriate radiative transfer model, though an example (for retrieval of cloud parameters) is supplied with the package.<\/p>\n<p>Version 2 was released in November 2004.<\/p>\n<h3>Further information<\/h3>\n<ul>\n<li><a href=\"https:\/\/nwp-saf.eumetsat.int\/site\/download\/documentation\/1dvar\/nwpsaf-mo-ud-010_1dvar_overview.pdf\">Overview of the NWP SAF 1D-Var packages<\/a> (PDF)<\/li>\n<li><a href=\"https:\/\/nwp-saf.eumetsat.int\/site\/download\/documentation\/ecmwf_1dvar\/nwpsaf-ec-ud-001.pdf\">ECMWF 1D-Var User\u2019s Guide<\/a> (PDF)<\/li>\n<\/ul>\n<h3>Brief outline of plans<\/h3>\n<ul>\n<li>Undertake maintenance as necessary.<\/li>\n<li>Further developments depend on user-requirements and other NWP SAF priorities.<\/li>\n<\/ul>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>ECMWF 1D-Var The ECMWF 1D-Var package is a generalised minimisation code applicable to a wide range of inversion problems for satellite data, and it is not set up to handle any particular instrument. It makes use of the M1QN3 software from INRIA (quasi-Newton method) and preconditions the state vector with the eigenvectors of the background error covariance. The code is in Fortran and documented. It cannot be treated as a \u2018black box\u2019 as various additional modules have to be interfaced to the ECMWF 1D-Var package before it will work. The user must define a control variable and interface an appropriate [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":609,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"footnotes":""},"class_list":["post-613","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/pages\/613","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/comments?post=613"}],"version-history":[{"count":0,"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/pages\/613\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/pages\/609"}],"wp:attachment":[{"href":"https:\/\/nwp-saf.eumetsat.int\/site\/wp-json\/wp\/v2\/media?parent=613"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}