Workshop: Paleoclimate states as future climate analogues
Location: DMI, Copenhagen
Time: From 09:00 2nd of may -3 May 2018
Organizers: Rasmus (CIC), Peter, Shuting, and Ida (DMI)
Participants: ice2ice partners (potentially few relevant external collaborators)
You can find the agenda here: Agenda_Analogues-workshop
You can find directions here: Getting_to_DMI
Please sign up using the following link, and share your ideas to help us shape the workshop:
https://goo.gl/forms/ysV71TBKYjvD7rHr2
[**Please sign up by March 23**]
- Contributions from both proxy and modeling experts are crucial for a successful workshop.
We hope to see many of you in Copenhagen soon!
Description:
One of the key themes in ice2ice is to what extent past abrupt changes have relevance for future climate change. Inspired by potentially similar warming trends in past (stadial-interstadial and glacial-interglacial) climates and future scenarios, we will discuss the applicability of paleoclimate states as analogues for future warming.
This workshop aims to intercompare proxy data reconstructions, paleoclimate modelling efforts, and future model projections with a particular focus on sea ice related warming in the Arctic (especially Greenland and the Nordic Seas region).
Specific topics during the workshop will be:
- Rate of warming and sea ice loss
Are the rates of warming and sea ice loss in the past, eg. MIS3 stadial-interstadials or the deglaciation (proxy + model), and future scenarios (model) comparable? When we talk of past and current/future change in the Arctic, how good is the analogue in terms of abruptness?
- Nordic Seas vs central Arctic Ocean
Comparison of past sea ice changes in the Nordic Seas (proxy + model) to future changes in the Arctic Ocean (model). If changes in the Nordic Seas during MIS3 should be used as a parallel for potential changes in the Arctic Ocean in a warmer climate (interglacial or future), two questions arise: how do the two oceans compare (e.g. vertical structure) and how would SST/sea ice changes in the two regions affect the atmosphere/Greenland. Specifically, can we use our collective model and proxy data to answer: (1) Is the impact of sea ice loss/SST increase similar for Nordic Seas (MIS3) and Arctic Ocean (interglacial or future), and (2) could the same mechanism lead to abrupt changes?
- Different drivers
When comparing current-to-future climate change with preindustrial-to-last-interglacial changes, or when comparing current-to-future with stadial-to-interstadial changes, we need to consider the different driving mechanisms. Compared to the “apparently unforced” stadial-to-interstadial changes, the two former changes are forced by variations in GHG concentrations and insolation, respectively. To what extent can the different signatures of insolation and GHG changes be disregarded? There are indications that the resulting SST state is dominant for many atmospheric impacts, such that the driver is of less importance, but this needs to be addressed carefully when making past vs future analogues.
Contributions to the above from both the proxy and modeling sides is crucial to a successful outcome of the workshop.
Mehmet Ilicak (Bergen) will give a talk on Friday, May 18 at 11am in RF016, NBI, Denmark he will discuss:
A novel method to represent mesoscale eddies in the ocean
PI science discussion:
Follow-up to Martin S’s see saw paper: Synergy paper including proxy data, and various Paleo-exps, MAS+Chuncheng+Margit+trond
Self organized map procedure NAO orientation-need to know what the proxies says. (Trond and Jens follow up, science point at PI meeting invite Martin Stendel and Chuncheng in end May PI meeting)
Msc Sam Black will defend his thesis investigating the chemistry in the Greenland shallow traverse cores obtained in 2015. Further Msc Patrick Stephan Zens defended his thesis in Uppsala in end of May, and has agreed to update us on his findings following the defense of Sam. You are all most welcome to join.
Below the two abstracts
Analysis of chemistry in 6 shallow cores from Northern Greenland
by Sam Black
This report examines a series of 6 short firn cores collected from the Greenland Ice Sheet in May 2015. The cores were collected by hand using a IDDO drill during the traverse from NEEM to NGRIP and analysed at the Centre for Ice and Climate using the institutions continuous flow analysis system. More specifically, this report aims to present a number of different ice core proxies measured from the cores, their similarities, differences and causes.
Aerosol Input and Snow Accumulation Rates on the Northern Greenland Ice Sheet –Reconstructed by means of Continuous Flow Analysis (CFA) of 6 shallow firn cores
by Patrick Stephan Zens
Ice, firn and snow cores from the Greenland ice sheet offer a unique opportunity to reconstruct past climate conditions. These can be analyzed with continuous flow analysis (CFA) in order to acquire proxy information about ancient atmospheric aerosol concentrations, snow accumulation rates or temperature variations, atmospheric composition, solar activity as well as volcanism and biological activity.
This project deals with high-resolution CFA applied on six shallow firn cores (A1-A6) from Northern Greenland taken during a 456 km long traverse from the deep ice core drilling sites NEEM to that called EGRIP. The practical part included CFA measurements by means of fluorescence spectroscopy for obtaining NH4 +, Ca2+ and H2O2, absorption spectroscopy for H+, an ion selective electrode (ISE) for Na+ as well as insoluble dust and water electrolytic conductivity measurements.
The analytical part consisted of calibrations of the measurements, the reconstruction of the depth scale of the snow/firn cores and defining annual layers using H2O2. Field density measurements and the annual layer thicknesses were used to identify annual mean snow accumulation rates.
These high-resolution firn records allowed determining accurate monthly maximum and minimum aerosol concentrations in order to evaluate seasonal deposition patterns and validate the applied dating method. The reconstructed ages ranged from 17 ± 1 to 54 ± 2 years along a northwest-southeast gradient. Statistical tests resulted merely for H2O2 in correlations between the three western cores, probably explained by the dating method, which forces the annual summer maxima and winter minima of H2O2 to correlate. Trend analysis resulted in no significant changes over time except for the conductivity measurements of the two longest/oldest firn cores. This is associated with decreasing acidifying anthropogenic sulfur emissions since the 1970’s.
Annual mean snow accumulation rates ranged from 0.235 ± 0.061 m w.eq.a-1 in the very west of the traverse to 0.103 ± 0.036 m w.eq.a-1 centered on the Greenland ice-divide. Correlation maps derived from ERA-Interim reanalysis were used, to indicate potential correlations between the six firn cores. Similar to the results for H2O2, a significant correlation could only be determined between the three westernmost cores. A significant increasing trend of snow accumulation since the 1960’s was
detectable for core A6 in the ice sheet’s interior.
These traverse cores represent point measurements in a large, highly variable and poorly studied region of Northern Greenland. Hence, more extensive investigations are essential to reduce the uncertainty, cancel out influencing snow surface processes and improve the representativeness of isolated locations. Conclusively, the produced results update impurity and accumulation datasets until 2015, determine trends and provide input for surface mass balance estimations and ground truth data
for satellite observations.
Keywords: Continuous flow analysis, Greenland, Shallow firn core, Aerosol, Snow accumulation,
Glaciochemistry
The EuroScience Open Forum will be hosted in July 2018 in Toulouse, France. The Université Fédérale Toulouse Midi-Pyrénées, together with an impressive number of national and regional institutions and partners, will be responsible for the event. Toulouse and the Région Occitanie offer a comprehensive research portfolio covering all disciplines and providing a scientific environment of great international repute with strong links with the industry, that ranks among the highest in France in terms of scientific production. EuroScience is convinced that Toulouse will add its name as another major European city to the European Cities of Science that have organized ESOF since 2004 in Stockholm.
Science workshop on blue blob
Margit «Convection and ventilation updates, new results» and Jonathan “How the Greenland-Scotland Ridge (GSR) shapes the Atlantic Meridional Ocean Circulation and controls low-to-high latitude heat transport”
Ice2ice DMI/NBI meeting
Please let Helle know if you have updates for the agenda.
Eystein’s presentation from Poland. «Abrupt change, future perspectives»
På fjeldet!
Science discussion possibly on:
2+2b combined: Cross model sensitivity studies NORESM and EC-Earth (plus Peter, Shuting, Stockholm)+JHC
run made over summer, science point for PI in autumn
Emilie and Kerim – Heinrich events vs DO-stadials