Nov
19
Mon
2018
Ice2ice Bergen meeting @ U1 Big meeting room
Nov 19 @ 09:00 – 12:00

Agenda will be announced later.

Nov
23
Fri
2018
PhD Defense by Diana Vladimirova
Nov 23 @ 13:00 – 17:00

Title: “High-resolution methane record of the RECAP ice core (Eastern Greenland) over the last climatic cycle”

Abstract: “Methane (CH4) is among the three most important greenhouse gases. Its concentration varied in the past and the only way to extract the information is to measure the past atmosphere samples trapped in the ice cores. We present the REnland ice CAP (RECAP) CH4 record covering the last glacial cycle (120 000 years).

The modern interglacial (Holocene) section (the last 11 700 years) represents the first continuous high-resolution methane record of the Northern Hemisphere and exhibits the centennial-scale variability. A possible explanation for this observation could be in the global teleconnection of the intertropical convergence zone and its influence on the monsoon activity, which in turn has an effect on the CH4 emissions for the tropical wetlands – the dominant source of methane.
During a part of the Last Glacial, we reveal that approximately 78 000 – 83 000 years ago an additional source of methane was active in the Northern Hemisphere. The environmental reconstructions suggest that it could be the boreal wetlands, exposed after the retreat of the ice sheet and the following drainage of ice-dammed lakes in the area.

As side projects, we also work on the improvement of the continuous flow analysis (CFA) technique for the gas applications – the technique used for the RECAP ice core measurements, and on the on-site CH4 measurements at the Eastern Greenland Ice core Project (EGRIP). We identify a diurnal variability of the CH4 concentration in the surface air an upper firn column, which was earlier considered as convectively mixed”.

Tid: 23. november 2018, kl. 13:00-17:00

Sted: Centre for Ice and Climate, Rockefeller Complex, Juliane Maries Vej 30, 2nd floor, room 235

Arrangør: Centre for Ice and Climate

Supervisor
Prof. Thomas Blunier, Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen.

Assessment Committee
Ass. Prof. Anders Svensson, Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen.
Ass. Prof. Giuliana Panieri, Centre for Arctic Gas Hydrate, Environment and Climate, UiT – The Arctic University of Norway.
Célia Sapart, Laboratoire de Glaciologie, Université Libre de Bruxelles.

Nov
26
Mon
2018
PhD defense Nicholas Rathmann
Nov 26 @ 13:00 – 17:00

Tid: 26. november 2018, kl. 13:00-17:00

Sted: Centre for Ice and Climate, rockefeller Complex, Juliane Maries Vej 30, 2nd floor, room 235

Arrangør: Centre for Ice and Climate

 

Abstract (long):
Nonlinear fluid motion occurs naturally in central components of the climate system. Studying such motion is instrumental for improving the accuracy and realism of models of climate components, which has important implications for future climate projections. This thesis presents four studies on the topic of nonlinear fluid dynamics addressing two subjects: the dynamics of ice sheet deformation and the dynamics of the turbulent energy cascade.
The first study investigates the controlling mechanisms of the observed 2016 seasonal speed-up of Zachariae and  Nioghalvfjerdsfjorden outlet glaciers in northeast Greenland, which drain a significant part of the Greenland ice sheet. From surface imagery made available by the newest generation of satellites, state-of-the-art velocity maps are derived, and the timings of processes potentially impacting the speed-up are estimated. By combining observations with numerical modelling, it is shown that the subglacial environment exerts an important control over the ice discharge rate of the region, which has implications for estimating the region’s contribution to near-term sea level rise.
The second study investigates the influence of strong single-maximum fabrics on the transient deformation of internal layers within ice sheets. By using a new Lagrangian numerical ice flow model, it is shown that discrete, strong single maximum layers — which may account for suppressed shearing along nonbasal crystallographic planes — are a plausible candidate for explaining the disturbed flow observed from ice-penetrating radar transects. The results have potential implications for interpreting ice-core stratigraphies and chronologies, as well as understanding of how internal disturbances might influence surrounding flow fields.
The third and fourth study address the origin of the transfer direction of kinetic energy between scales of motion  (upscale/downscale) in fully developed turbulence using the spectral-helical decomposition of the velocity field. In this decomposition, the nonlinear term in the Navier–Stokes equation becomes to a sum over eight distinct types of three-wave interactions. In the third study, a simple model (a shell model) is introduced to investigate the behaviour of the eight types of nonlinear interactions, which is compared to a linear stability analysis, finding a fair agreement.
In the fourth study, a subset of the three-wave interactions are shown to conserve a new positive-definite quadratic quantity in addition to kinetic energy, which cause the interactions to contribute to a reverse transfer of energy in three dimensions (small to large scales) in analogy to two-dimensional turbulence. Understanding the energy transfer directionality, and possible ties between two- and three-dimensional turbulence, has implications for geophysical flows such as the free atmosphere and oceans where vertical motion in many places is suppressed, thereby affecting predictability time scales and the transport of energy and momentum in climate.
Dec
4
Tue
2018
PI meeting @Bergen
Dec 4 – Dec 5 all-day
Dec
6
Thu
2018
Ice2ice Bergen meeting @ U1 Big meeting room
Dec 6 @ 13:00 – 15:00

Agenda will be announced later.

Jan
14
Mon
2019
PI meeting @Bergen
Jan 14 @ 15:46 – Jan 15 @ 16:46
Jan
25
Fri
2019
Internal local economy status meetings for PI’s prior to reporting 54 month
Jan 25 all-day

Internal local economy status meetings for PI’s prior to reporting 56 month.

See slides from Hege from May meeting in Copenhagen 03.05.18-Ice2Ice-Adm.meeting

 

@Jens and Bo see the local NBI  Reporting calendar NBI-2019 towards the 54 month report

 

Feb
21
Thu
2019
PI meeting @CPH
Feb 21 – Feb 22 all-day
Mar
4
Mon
2019
54 months economy draft reporting to Hege
Mar 4 all-day

Draft/preliminary template/report

Draft ERC Budget tables

Draft Form C completed in the portal if possible

Work force table (final)

Mar
9
Sat
2019
PI bootcamp @Bergen
Mar 9 – Mar 12 all-day
Mar
31
Sun
2019
54 month ice2ice – Financial reporting to ERC
Mar 31 all-day
Apr
8
Mon
2019
EGU 2019
Apr 8 – Apr 12 all-day

https://www.egu2019.eu/

 

ice2ice led sessions:

Session CL1.11/CR5.6

The state-of-the-art in ice coring sciences (StatICS) (co-organized) 

Convener: Paul Vallelonga  Co-conveners: Thomas Blunier , Anja Eichler , Vasileios Gkinis , Rachael Rhodes

Session CL1.15/CR1.9/OS1.25

On the dynamics of Dansgaard-Oeschger events; perspectives from paleoclimate data and modeling (co-organized) 

Convener: Kerim Nisancioglu  Co-conveners: Jonathan Rheinlænder , Margit Simon , Emlilie Capron , Camille Li
PI meeting @EGU
Apr 8 @ 18:00 – 22:00
May
6
Mon
2019
Final ice2ice all staff
May 6 – May 10 all-day

More info will follow