BEGIN:VCALENDAR VERSION:2.0 PRODID:-//18.83.4.138//NONSGML kigkonsult.se iCalcreator 2.20// CALSCALE:GREGORIAN METHOD:PUBLISH X-WR-CALNAME:Oceans at MIT X-WR-CALDESC:Striving to understand\, harness and sustain Earth'\;s def ining frontier. X-FROM-URL:http://oceans.mit.edu X-WR-TIMEZONE:America/New_York BEGIN:VTIMEZONE TZID:America/New_York X-LIC-LOCATION:America/New_York BEGIN:STANDARD DTSTART:20171105T020000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 RDATE:20181104T020000 TZNAME:EST END:STANDARD BEGIN:DAYLIGHT DTSTART:20180311T020000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 TZNAME:EDT END:DAYLIGHT END:VTIMEZONE BEGIN:VEVENT UID:t046l603eq5d44tkp0v760gue8@google.com DTSTAMP:20180503T075918Z CATEGORIES: CONTACT: DESCRIPTION:A new perspective on an old problem: understanding the observed variability of the South Asian monsoon\n\nRecent theoretical advances ind icate that the South Asian monsoon (SAM) should be viewed as an energetica lly-direct cross-equatorial Hadley circulation\, with the monsoonal precip itation primarily occurring in its ascending branch\, rather than as a lar ge land-sea breeze circulation. In this talk\, we explore the implications of these emerging theories for the observed variability of the SAM on sea sonal and longer time scales. We start by using the atmospheric moisture b udget to introduce a novel objective index for the onset and retreat of th e SAM\, which robustly captures the expected seasonal transitions in preci pitation and winds and eliminates the need for arbitrarily selected thresh olds. Using this index\, we show how the SAM onset and retreat are associa ted with a coherent set of seasonal transitions in circulation\, jet strea ms\, precipitation\, energetics\, and momentum balance throughout the SAM sector. We also use the atmospheric moisture budget to define a new index for the SAM strength on interannual time scales. We show that interannual variability in SAM net precipitation is primarily caused by variations in winds rather than variations in humidity\, and that strong monsoons are as sociated with a northward expansion of the overturning circulation and a d ecreased near-surface land-sea thermal contrast\, in disagreement with the traditional view of the SAM as a sea-breeze circulation. We also find tel econnections between SAM strength and temperatures\, winds\, and momentum and energy transports in the southern hemisphere extra tropics\, which sug gest new directions for future research to improve our understanding of th e mechanisms involved in SAM variability. DTSTART;TZID=America/New_York:20170424T120000 DTEND;TZID=America/New_York:20170424T130000 LOCATION:54-915 SEQUENCE:0 SUMMARY:PAOC Colloquium: Simona Bordoni (Caltech) URL:http://oceans.mit.edu/event/paoc-colloquium-simona-bordoni-caltech-2 X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\n\\n\\nA new perspectiv e on an old problem: understanding the observed variability of the South A sian monsoon\n\nRecent theoretical advances indicate that the South Asian monsoon (SAM) should be viewed as an energetically-direct cross-equatorial Hadley circulation\, with the monsoonal precipitation primarily occurring in its ascending branch\, rather than as a large land-sea breeze circulat ion. In this talk\, we explore the implications of these emerging theories for the observed variability of the SAM on seasonal and longer time scale s. We start by using the atmospheric moisture budget to introduce a novel objective index for the onset and retreat of the SAM\, which robustly capt ures the expected seasonal transitions in precipitation and winds and elim inates the need for arbitrarily selected thresholds. Using this index\, we show how the SAM onset and retreat are associated with a coherent set of seasonal transitions in circulation\, jet streams\, precipitation\, energe tics\, and momentum balance throughout the SAM sector. We also use the atm ospheric moisture budget to define a new index for the SAM strength on int erannual time scales. We show that interannual variability in SAM net prec ipitation is primarily caused by variations in winds rather than variation s in humidity\, and that strong monsoons are associated with a northward e xpansion of the overturning circulation and a decreased near-surface land- sea thermal contrast\, in disagreement with the traditional view of the SA M as a sea-breeze circulation. We also find teleconnections between SAM st rength and temperatures\, winds\, and momentum and energy transports in th e southern hemisphere extra tropics\, which suggest new directions for fut ure research to improve our understanding of the mechanisms involved in SA M variability. END:VEVENT END:VCALENDAR