PKTP‰;¦Y[WHHrefs.MYDDüÓÿÿï?ALevermann, Anders Schewe, Jacob Petoukhov, Vladimir Held, Hermann2009.Basic mechanism for abrupt monsoon transitions 20572-20577/Proceedings of the National Academy of Sciences10649December 8, 2009 Monsoon systems influence the livelihood of hundreds of millions of people. During the Holocene and last glacial period, rainfall in India and China has undergone strong and abrupt changes. Though details of monsoon circulations are complicated, observations reveal a defining moisture-advection feedback that dominates the seasonal heat balance and might act as an internal amplifier, leading to abrupt changes in response to relatively weak external perturbations. Here we present a minimal conceptual model capturing this positive feedback. The basic equations, motivated by observed relations, yield a threshold behavior, robust with respect to addition of other physical processes. Below this threshold in net radiative influx, , no conventional monsoon can develop; above , two stable regimes exist. We identify a nondimensional parameter that defines the threshold and makes monsoon systems comparable with respect to the character of their abrupt transition. This dynamic similitude may be helpful in understanding past and future variations in monsoon circulation. Within the restrictions of the model, we compute for current monsoon systems in India, China, the Bay of Bengal, West Africa, North America, and Australia, where moisture advection is the main driver of the circulation.2http://www.pnas.org/content/106/49/20572.abstract 10.1073/pnas.0901414106PKRP‰;¸ñI/Ø*Ø*refs.FRMþ 0¾B< !¾// €!€HÿPRIMARYÿyearIndexÿØ 6©¯ByP/) idreference_type text_stylesauthoryear title pages secondary_title volume numbernumber_of_volumessecondary_authorplace_published publishersubsidiary_authoredition keywords type_of_workdate2)  abstractlabelurltertiary_titletertiary_author notes isbn custom_1 custom_2 custom_3 custom_4alternate_titleaccession_number call_number short_title custom_5 custom_6sectionoriginal_publicationH) reprint_editionreviewed_itemauthor_addressimagecaption custom_7 electronic_resource_number link_to_pdf translated_author translated_titlename_of_databasedatabase_providerresearch_notes language access_datelast_modified_date !! Hú!Hú!Hú! (Hú! 3Hú! >Hú! IHú! THú!_Hú!jHú!uHú! €Hú!‹Hú!–Hú! ¡Hú! ¬Hú!·Hú! ÂHú!ÍHú!ØHú!ãHú!îHú! ùHú! Hú! Hú! Hú! %Hú! 0Hú!;Hú!FHú! QHú! \Hú! gHú! rHú!}Hú!ˆHú!“Hú!žHú!©Hú!´Hú!¿Hú! ÊHú! ÕHú! àHú! ëHú! öHú!Hú! Hú!Hú! "Hú! -Hú!8Hú!ÿidÿreference_typeÿtext_stylesÿauthorÿyearÿtitleÿpagesÿsecondary_titleÿvolumeÿnumberÿnumber_of_volumesÿsecondary_authorÿplace_publishedÿpublisherÿsubsidiary_authorÿeditionÿkeywordsÿtype_of_workÿdateÿabstractÿlabelÿurlÿtertiary_titleÿtertiary_authorÿnotesÿisbnÿcustom_1ÿcustom_2ÿcustom_3ÿcustom_4ÿalternate_titleÿaccession_numberÿcall_numberÿshort_titleÿcustom_5ÿcustom_6ÿsectionÿoriginal_publicationÿreprint_editionÿreviewed_itemÿauthor_addressÿimageÿcaptionÿcustom_7ÿelectronic_resource_numberÿlink_to_pdfÿtranslated_authorÿtranslated_titleÿname_of_databaseÿdatabase_providerÿresearch_notesÿlanguageÿaccess_dateÿlast_modified_dateÿPKTP‰;¦Y[WHHrefs.MYDPKRP‰;¸ñI/Ø*Ø*nrefs.FRMPKll1