BEGIN:VCALENDAR VERSION:2.0 METHOD:PUBLISH CALSCALE:GREGORIAN PRODID:-//WordPress - MECv7.37.0//EN X-ORIGINAL-URL:https://essic.umd.edu/ X-WR-CALNAME:ESSIC X-WR-CALDESC:UMD - Earth System Science Interdisciplinary Center X-WR-TIMEZONE:America/New_York BEGIN:VTIMEZONE TZID:America/New_York X-LIC-LOCATION:America/New_York BEGIN:DAYLIGHT TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:EDT DTSTART:20260308T030000 RRULE:FREQ=YEARLY;BYMONTH=03;BYDAY=2SU END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:-0400 TZOFFSETTO:-0500 TZNAME:EST DTSTART:20261101T010000 RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU END:STANDARD END:VTIMEZONE REFRESH-INTERVAL;VALUE=DURATION:PT1H X-PUBLISHED-TTL:PT1H X-MS-OLK-FORCEINSPECTOROPEN:TRUE BEGIN:VEVENT CLASS:PUBLIC UID:MEC-397fc000ce6f8e94df510c3ff5d86a61@essic.umd.edu DTSTART;TZID=America/New_York:20231120T080000 DTEND;TZID=America/New_York:20231120T180000 DTSTAMP:20250905T130805Z CREATED:20250905 LAST-MODIFIED:20250905 PRIORITY:5 SEQUENCE:1 TRANSP:OPAQUE SUMMARY:Drivers of Subseasonal To Seasonal Precipitation Over the Southwest Us: Potential Predictability, Case Studies and Identified Biases in Current Dynamical Models DESCRIPTION:This event has passed. See the seminar recording here:\n\n \n\n\nProf. Gudrun Magnusdottir\nDepartment of Earth System Science\nUniversity of California Irvine\nMonday November 20, 2023, 2 PM ET\nAbstract:\nThe talk will focus on issues related to variability, potential predictability and hindcasts of Southwest US precipitation during the water year (cool months), highlighting work in my group at UC Irvine.\nI will start by showing results from a study on potential predictability where we run a set of numerical experiments using the Whole Atmosphere Community Climate Model (WACCM). In addition to prescribing observed sea surface temperature and sea ice concentration (AMIP-type experiments), observed variability from the MERRA-2 reanalysis is prescribed in the tropics and/or in the Arctic through nudging of wind and temperature (AMIP-plus experiments). These experiments reveal how a perfect prediction of tropical and/or Arctic variability in the model would impact the prediction of seasonal rainfall over the Southwest US, at various time scales. \nImposing tropical variability improves the representation of the observed North Pacific atmospheric circulation, and the associated Southwest US seasonal precipitation. This is also the case at the subseasonal time scale. When additional nudging is applied in the Arctic, the model skill improves even further, suggesting that improving seasonal predictions at high latitudes may also benefit prediction of Southwest US precipitation. However, subseasonal tropical variability (mostly the MJO), may interfere and weaken ENSO teleconnections with Southwest US precipitation. This and the strong 2016 El Nino that only resulted in average precipitation, motivated a study of how non-ENSO Pacific teleconnections regulate precipitation in the region, which showed that in the CESM2 large ensemble experiment they are too ENSO-like. \nI will then briefly describe current research that is focused on examining biases in the dynamical S2S models, focusing on the 3-6 week timescale, and experimenting with the AI weather forecast models, extending predictions into the subseasonal range. Some preliminary results will be presented.\n\nBiosketch:\n Professor Gudrun Magnusdottir got her BS in Physics from the University of Iceland, her MS in atmospheric science from Colorado State University following which she worked as a meteorologist in the Icelandic Meteorological Office. She returned to Colorado State University for a PhD. She was a postdoctoral researcher at the Department of Applied Mathematics and Theoretical Physics (DAMTP) at the University of Cambridge. She joined the University of California Irvine in 1995, the year in which the program in Geoscience became the Department of Earth System Science (ESS). She is a professor and past chair of ESS. She is a Fellow of the American Meteorological Society. \nWebinar:\nEvent site: https://go.umd.edu/magnusdottir ( https://go.umd.edu/magnusdottir )\nZoom Webinar: https://go.umd.edu/magnusdottirwebinar ( https://go.umd.edu/magnusdottirwebinar )\nZoom Meeting ID:\nZoom password: essic\nUS Toll: +13017158592\nGlobal call-in numbers: https://umd.zoom.us/u/aMElEpvNu ( https://umd.zoom.us/u/aMElEpvNu )\nFor IT assistance:\nCazzy Medley: cazzy@umd.edu ( mailto:cazzy@umd.edu )\n\nResources:\nSeminar schedule & archive: https://go.umd.edu/essicseminar\nSeminar Google calendar: https://go.umd.edu/essicseminarcalendar\nSeminar recordings on Youtube: https://www.youtube.com/user/ESSICUMD ( https://www.youtube.com/user/ESSICUMD )\n URL:https://essic.umd.edu/events/drivers-of-subseasonal-to-seasonal-precipitation-over-the-southwest-us-potential-predictability-case-studies-and-identified-biases-in-current-dynamical-models/ CATEGORIES:Fall 2023 END:VEVENT END:VCALENDAR