{"650324":{"#nid":"650324","#data":{"type":"event","title":"How many Snowballs out there?","body":[{"value":"\u003Ch4\u003E\u003Cstrong\u003EThe School of Earth and Atmospheric Sciences Presents Dr.\u0026nbsp;Antonello Provenzale, Institute of Geosciences and Earth Resources, CNR\u003C\/strong\u003E\u003C\/h4\u003E\r\n\r\n\u003Cp\u003EHow many Snowballs out there?\u003C\/p\u003E\r\n\r\n\u003Cdiv\u003E\r\n\u003Cp\u003EPlanetary climates are complex systems that include a multitude of stabilizing (negative) and destabilizing (positive) feedback loops. One of them, the ice-albedo feedback, is possibly causing multiple stable states in Earth\u0026rsquo;s climate, with the alternation between ice-covered conditions (the most extreme being the so-called \u003Cem\u003ESnowball\u003C\/em\u003E) and warm states. Here, we adopt the view of climate as a dynamical system, strip down its complexity using a simple one-dimensional Energy Balance Model called ESTM and explore the conditions leading to bistability in the climate of Earth-like planets, briefly recalling the potential role of stochastic resonance.\u003C\/p\u003E\r\n\r\n\u003Cp\u003EWe shall then consider the effects of the ice-albedo feedback for a wide range of orbital and planetary parameters such as distance from the star, ellipticity, obliquity and atmospheric pressure. Other mechanisms for bistability will be mentioned, such as the vegetation-albedo and vegetation-moisture feedbacks, and the crucial role of atmospheric composition. Implications on planetary habitability will finally be considered.\u003C\/p\u003E\r\n\u003C\/div\u003E\r\n","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":"","field_summary_sentence":[{"value":"A seminar by Dr. Antonello Provenzale, School of Earth and Atmospheric Sciences"}],"uid":"34458","created_gmt":"2021-08-31 20:08:47","changed_gmt":"2021-11-01 11:59:31","author":"nlawson3","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2021-12-02T11:00:00-05:00","event_time_end":"2021-12-02T12:00:00-05:00","event_time_end_last":"2021-12-02T12:00:00-05:00","gmt_time_start":"2021-12-02 16:00:00","gmt_time_end":"2021-12-02 17:00:00","gmt_time_end_last":"2021-12-02 17:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"hg_media":{"650323":{"id":"650323","type":"image","title":"Antonello Provenzale","body":null,"created":"1630440307","gmt_created":"2021-08-31 20:05:07","changed":"1630440307","gmt_changed":"2021-08-31 20:05:07","alt":"","file":{"fid":"246812","name":"Antonello Provenzale.jpg","image_path":"\/sites\/default\/files\/images\/Antonello%20Provenzale.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/images\/Antonello%20Provenzale.jpg","mime":"image\/jpeg","size":7456,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/Antonello%20Provenzale.jpg?itok=x7zHnqCd"}}},"media_ids":["650323"],"groups":[{"id":"364801","name":"School of Earth and Atmospheric Sciences (EAS)"}],"categories":[],"keywords":[{"id":"175623","name":"EAS Seminar"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[{"id":"78761","name":"Faculty\/Staff"},{"id":"177814","name":"Postdoc"},{"id":"174045","name":"Graduate students"},{"id":"78751","name":"Undergraduate students"}],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EDr. Annalisa Bracco\u003C\/p\u003E\r\n","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}