Major Events

No meetings, workshops, or other special events are currently announced.

+ Past Meetings & Workshops

Other Upcoming Events

Following are upcoming seminars, workshops and other events of interest to GISS staff and our research partners. Please note that due to security regulations, these presentations are not open to the general public.

Friday, Sep. 9, 2016
11:00 a.m. to 12:15 p.m.
Friday Seminar
Topic: Time variable eddy mixing in the global Sea Surface Salinity maxima
Speaker: Julius Busecke (LDEO)
Abstract: Read More
Contact: Darren Engwirda

Friday Seminar
Speaker: Julius Busecke (LDEO)
Title: Time variable eddy mixing in the global Sea Surface Salinity maxima

Abstract: Lateral mixing by mesoscale eddies is widely recognized as a crucial mechanism for the global ocean circulation and the associated heat/salt/tracer transports. The Salinity in the Upper Ocean Processes Study (SPURS) confirmed the importance of eddy mixing for the surface salinity fields even in the center of the subtropical gyre of the North Atlantic - sometimes described as an 'eddy desert'. Several studies have since estimated the relevance of eddy mixing compared to the surface forcing by net evaporation - mostly focused on the North Atlantic. Here we present a novel approach to quantify and compare the importance of eddy mixing for the saltiest regions of the world ocean. Global 2D passive tracer experiments in a 1/10 degree MITgcm setup are initialized with climatological salinity fields and stirred with observed surface velocities, taking full advantage of the longstanding record of altimetry observations. The importance of eddy mixing is quantified using a Lagrangian framework (salinity coordinates) which eliminates advection from the salinity/volume budget, focussing on the resulting water masses which are ultimately advected through the shallow overturning circulation in all major ocean basins. This enables us to resolve temporal variability on seasonal to inter annual time scales. Investigation of the mechanisms for variability reveal regional differences with possible implications for long term surface salinity variability.

Web link: Read more

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Thursday, Sep. 15, 2016
11:00 a.m. to 12:30 p.m.
CU Climate Center Lecture
Speaker: Stephen Meyers (University of Wisconsin)
Abstract: Read More
Contact: Allegra N. LeGrande

CU Climate Center Lecture
Speaker: Stephen Meyers (University of Wisconsin)

Abstract: Climate Center (LDEO/GISS) Lecture

Web link: Read more

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Friday, Sep. 30, 2016
11:00 a.m. to 12:15 p.m.
Friday Seminar
Topic: Water Mass Transformation Under Southern Ocean Sea Ice
Speaker: Ryan Abernathey (LDEO)
Abstract: Read More
Contact: Darren Engwirda

Friday Seminar
Speaker: Ryan Abernathey (LDEO)
Title: Water Mass Transformation Under Southern Ocean Sea Ice

Abstract: This study quantifies the role of Antarctic sea ice in the transformations of water masses within the Southern Ocean State Estimate (SOSE). Winds drive a strong export of sea ice away from the continent towards the open ocean. The resulting freshwater fluxes at the ocean surface dominate the Southern Ocean freshwater budget (compared with direct precipitation and glacial melt), and these strong fluxes have a major impact on density, stratification, and circulation. Using Walin’s water mass transformation framework, we isolate the contributions of brine rejection, ice melt, and snow interception on the modification of seawater density. Together with direct atmospheric precipitation - evaporation, glacial melt, surface heat flux, and interior mixing, these processes provide the thermodynamic transformations necessary to sustain the meridional overturning circulation. The transformation analysis reveals that sea-ice freshwater fluxes are the main contributor to the transformation of upwelling Upper Circumpolar Deep Water, pushing it primarily towards lighter Antarctic Intermediate and Subantarctic Mode Water but also partly toward denser classes. We also examine the seasonal cycle in transformation, revealing a subtle interplay between brine rejection and upper ocean mixing. Overall these results indicate a tight coupling between Antarctic sea ice and the upper branch of the Southern Ocean overturning circulation.

Web link: Read more

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Friday, Oct. 7, 2016
11:00 a.m. to 12:30 p.m.
Friday Seminar
Speaker: Michael Previdi (LDEO)
Abstract: Read More
Contact: Darren Engwirda
Tuesday, Oct. 11, 2016
11:00 a.m. to 12:15 p.m.
NExSS Seminar
Speaker: Sukrit Ranjan (Harvard University)
Abstract: Read More
Contact: Tony Del Genio

NExSS Seminar
Speaker: Sukrit Ranjan (Harvard University)
Title: TBD

Abstract: TBD

Web link: Read more

[ Close ]

Friday, Oct. 28, 2016
11:00 a.m. to 12:30 p.m.
Friday Seminar
Topic: Satellite observations of the stratosphere
Speaker: Bill Randel (NCAR/ACOM)
Contact: Allegra N. LeGrande

This event listing was last updated 2016-08-26.

Seminars & Colloquia

Most seminars at NASA GISS are held during the academic year, September through May.

Formal seminar presentations by visiting scientists are held many Fridays at 11:00 a.m.

Informal lunchtime presentations by GISS staff take place on Wednesdays at 1:00 p.m. about twice per month.

Other special seminars occur from time to time as visitors' schedules permit.

Security Note

Regulations require that visitors arrange in advance for a building pass. All persons attending a NASA GISS seminar or colloquium should contact the event host at least two business days in advance of the event for assistance. Please include your affiliation in your e-mail.

Special arrangements must be made for persons who are not U.S. citizens or U.S. permanent residents. Such persons should contact the event host at least seven business days in advance of visiting GISS.

Effective July 21, 2014, implementation of Phase II of the Real-ID Act (2005) restricts the use of state ID from non-compliant states (including New York) as an acceptable form of identification for federal facilities such as NASA GISS. If you have scheduled a visit to GISS and only have a standard driver's license from a non-compliant state, please be sure to bring a second form of ID (passport, military ID, etc.).