Listed below are upcoming seminars, workshops and other events of interest to the staff of NASA's Goddard Institute for Space Studies and to our research partners.
Please consult with the event host/contact for connection details if you wish to remotely join any event marked as "Virtual" or "Hybrid".
This event listing was last updated 2025-07-07. All times shown are New York City local.
- July 8, 2025
- 11 a.m. to 12:15 p.m. — Virtual
- Sea Level Rise Seminar
- Topic: Impacts of Temperature- and Stress-Dependent Rheology on Ice-Shelf-Front Bending
- Speaker: Emily Glazer (Columbia/LDEO)
- More info: Abstract
- Host/Contact: Patrick Alexander
Sea Level Rise Seminar
Speaker: Emily Glazer (Columbia/LDEO)
Title: Impacts of Temperature- and Stress-Dependent Rheology on Ice-Shelf-Front Bending
This is an on-line, virtual presentation only. Please consult with event host Patrick Alexander for connection details.
Abstract:
Classical treatments of ice-shelf bending suggest that shelf fronts should bend downwards due to the distribution of hydrostatic water pressure. However, lidar data show several instances of upward-bending ice-shelf fronts. While this phenomenon is often attributed to a buoyant force from a submerged ice bench, recent work suggests that vertical variations in ice viscosity, driven by temperature gradients, can induce an internal bending moment that causes uplift even in the absence of a bench. Comparing models of this novel bending mechanism with observations can help constrain the parameters describing ice rheology, and improve predictions of ice-shelf calving and sea-level rise.
We present the first two-dimensional, viscoelastic models of ice-shelf bending with temperature- and depth-dependent ice softness. Using a standard Glen's flow law (n = 3), our results confirm that an ice-shelf front can bend upwards with a sufficiently cold surface temperature and strong temperature dependence of viscosity. We extend this idea by incorporating more realistic ice rheology that combines two viscous creep mechanisms: grain-boundary sliding (n = 1.8) and dislocation creep (n = 4). Analytic results and preliminary 2D models show that this more complex rheology still produces a positive bending moment, and may even do so at warmer surface temperatures than the simpler model predicted.
Our models confirm that internal viscosity gradients alone can drive upward bending, and that the resulting edge deflection actually outpaces the thin-plate prediction due to a two-dimensional "bulge" effect. We also find that this uplift mechanism produces shorter flexural wavelengths than the submerged bench mechanism, providing a way to distinguish between causes of upward bending in lidar data. Sonar measurements of the ice-shelf-front shape may also help test this mechanism and place new constraints on ice rheology.
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- July 16, 2025
- 11 a.m. to 12 p.m. — Virtual
- IRI Climate Forecast Briefing
- Host/Contact: Andrew W. Robertson
- August 4, 2025
- 2 p.m. to 5 p.m. —
- Miriam Nielsen Dissertation Defense
- Speaker: Miriam Nielsen (Columbia Univ)
- Host/Contact: Kate Marvel
- August 19, 2025
- 11 a.m. to 12:15 p.m. — Virtual
- Sea Level Rise Seminar
- Topic: Thwaites glacier grounding line melt
- Speaker: Mainak Mondal (NYU)
- Host/Contact: Patrick Alexander
- August 20, 2025
- 11 a.m. to 12 p.m. — Virtual
- IRI Climate Forecast Briefing
- Host/Contact: Andrew W. Robertson
- September 17, 2025
- 11 a.m. to 12 p.m. — Virtual
- IRI Climate Forecast Briefing
- Host/Contact: Andrew W. Robertson
- October 15, 2025
- 11 a.m. to 12 p.m. — Virtual
- IRI Climate Forecast Briefing
- Host/Contact: Andrew W. Robertson
- October 20, 2025
- 9 a.m. to 5 p.m. —
- Historical and Paleoclimate Aerosol Radiative Effects Workshop
- More info: Abstract, Web Link
- Host/Contact: Kostas Tsigaridis
Historical and Paleoclimate Aerosol Radiative Effects Workshop
Abstract:
Constraining uncertainty in past radiative effects for non-CO2 components like dust and other aerosols play a critical role in understanding climate feedbacks and effective climate sensitivity, yet their contributions remain poorly quantified. Paleoclimate reconstructions reveal that natural aerosol emissions, including wildfire and dust, varied from the Last Glacial Maximum through the preindustrial era to today, and these variations are not captured in the latest CMIP6 simulations. This discrepancy between observations and model estimates of aerosol changes challenges the common assumption in many climate models that historical and paleoclimate aerosol preindustrial emissions are well-constrained. Consequently, current model-based estimates of aerosol radiative forcing and climate sensitivity likely underestimate uncertainty by neglecting the uncertainty in emissions. In this workshop, we seek to bring together experts in paleoclimate, aerosol radiative forcing, and climate sensitivity to develop coordinated strategies to assess observational and modeling constraints on past emissions and to characterize the resulting radiative forcing uncertainties.
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- October 21, 2025
- 9 a.m. to 5 p.m. —
- Historical and Paleoclimate Aerosol Radiative Effects Workshop
- More info: Abstract, Web Link
- Host/Contact: Kostas Tsigaridis
Historical and Paleoclimate Aerosol Radiative Effects Workshop
Abstract:
Constraining uncertainty in past radiative effects for non-CO2 components like dust and other aerosols play a critical role in understanding climate feedbacks and effective climate sensitivity, yet their contributions remain poorly quantified. Paleoclimate reconstructions reveal that natural aerosol emissions, including wildfire and dust, varied from the Last Glacial Maximum through the preindustrial era to today, and these variations are not captured in the latest CMIP6 simulations. This discrepancy between observations and model estimates of aerosol changes challenges the common assumption in many climate models that historical and paleoclimate aerosol preindustrial emissions are well-constrained. Consequently, current model-based estimates of aerosol radiative forcing and climate sensitivity likely underestimate uncertainty by neglecting the uncertainty in emissions. In this workshop, we seek to bring together experts in paleoclimate, aerosol radiative forcing, and climate sensitivity to develop coordinated strategies to assess observational and modeling constraints on past emissions and to characterize the resulting radiative forcing uncertainties.
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- October 22, 2025
- 9 a.m. to 5 p.m. —
- Historical and Paleoclimate Aerosol Radiative Effects Workshop
- More info: Abstract, Web Link
- Host/Contact: Kostas Tsigaridis
Historical and Paleoclimate Aerosol Radiative Effects Workshop
Abstract:
Constraining uncertainty in past radiative effects for non-CO2 components like dust and other aerosols play a critical role in understanding climate feedbacks and effective climate sensitivity, yet their contributions remain poorly quantified. Paleoclimate reconstructions reveal that natural aerosol emissions, including wildfire and dust, varied from the Last Glacial Maximum through the preindustrial era to today, and these variations are not captured in the latest CMIP6 simulations. This discrepancy between observations and model estimates of aerosol changes challenges the common assumption in many climate models that historical and paleoclimate aerosol preindustrial emissions are well-constrained. Consequently, current model-based estimates of aerosol radiative forcing and climate sensitivity likely underestimate uncertainty by neglecting the uncertainty in emissions. In this workshop, we seek to bring together experts in paleoclimate, aerosol radiative forcing, and climate sensitivity to develop coordinated strategies to assess observational and modeling constraints on past emissions and to characterize the resulting radiative forcing uncertainties.
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Meetings and Workshops
Forthcoming meetings, workshops, and other special events that will be hosted by GISS staff include the following:
Workshop on Characterizing Historical and Paleoclimate Aerosol Radiative Effects
Oct. 20-22, 2025.
For information, contact
Kostas Tsigaridis.
Seminars and Colloquia
Almost all seminars may be attended virtually over the Internet, and interested persons should contact the event host for connection details. Some events may be held "hybrid", meaning they are presented in person, but the locations will be varied
Informal Lunch Seminars take place on Wednesdays at 1 p.m. two or three times per month, mostly during the academic year.
ROCKE-3D Seminars discussing topics of interest to exoplanetary and paleoclimate researchers are held from time to time.
GISS staff also organize a series of Sea Level Rise Seminars on Tuesday mornings at 11 a.m., with presentations by scientists from numerous research institutions. This seminar is two or three times per month, year-round.
Videos of many past seminar presentations and other presentations may be found on YouTube.