News & Events Overview

Conference Calender


22.09.2020 |

(AC)³ PI Vera Schemann gives an online talk within the framework of the STEM activities “Zukunftsfeld Mathematik” from Uni Bremen via Zoom on 22 September 2020. Further information can be found here.

16.06.2020 |

Vortragsreihe Exkurs

Die Arktis verschwindet! – Wie wir der Eisschmelze auf die Spur kommen
Prof. Dr. Susanne Crewell

NEW DATE: 16 June 2020

Der Klimawandel erwärmt die Erde. Doch warum erhöht sich die Temperatur in der Arktis schneller als in anderen Regionen? Während sich global die bodennahe Temperatur um etwa ein Grad erhöht hat, sind die beobachteten Temperaturänderungen in der Arktis mehr als doppelt so hoch. Zeitgleich wird das Meereis dünner und in der Fläche weniger.

exkurs-Video: „Die Arktis verschwindet!” von Prof. Susanne Crewell

Weitere Informationen:

21.02.2020 |

Sandro Dahlke successfully defended his PhD thesis

As one of our first PhD students from phase I, Sandro Dahlke from AWI-Potsdam successfully defended his PhD thesis with the title “Rapid climate changes in the Arctic region of Svalbard: Processes, implications and representativeness for the broader Arctic”.

Congratulations to him!

Sandro Dahlke (AWI-Potsdam) after his PhD defense with his supervisors and reviewers.
Sandro Dahlke (AWI-Potsdam) after his PhD defense with his supervisors and reviewers.
23.12.2019 |

Release of Nature Climate Change paper by Cohen et al., 2020


The Arctic has warmed more than twice as fast as the global average since the late twentieth century, a phenomenon known as Arctic amplification (AA). Recently, there have been considerable advances in understanding the physical contributions to AA, and progress has been made in understanding the mechanisms that link it to midlatitude weather variability. Observational studies overwhelmingly support that AA is contributing to winter continental cooling. Although some model experiments support the observational evidence, most modelling results show little connection between AA and severe midlatitude weather or suggest the export of excess heating from the Arctic to lower latitudes. Divergent conclusions between model and observational studies, and even intramodel studies, continue to obfuscate a clear understanding of how AA is influencing midlatitude weather.

Full article can be found here.

Figure adopted from Cohen et al., 2020, Nat. Clim. Change,
Figure adopted from Cohen et al., 2020, Nat. Clim. Change,
25.11.2019 |

Approval of phase II of (AC)³

We made it!!! Deutsche Forschungsgemeinschaft (DFG) has approved our proposal for the 2nd phase of (AC)³. For the next four years we can continue our research on the Arctic climates changes using the effective concept of combining campaign observations with regional process and global climate modelling. The overarching goals for the 2nd phase are to identify, investigate, and evaluate the key processes contributing to Arctic amplification, to improve the understanding of the local and remote feedback mechanisms to Arctic amplification, and quantify their relative importance for Arctic amplification.

A press release has been published on the Deutsche Forschungsgemeinde (DFG) website to cover news on the SFB/TR 172 on Artic Amplification. Link to DFG PR

29.05.2019 |

Wendisch et al., 2019, “The Arctic Cloud Puzzle: Using ACLOUD/PASCAL Multi-Platform Observations to Unravel the Role of Clouds and Aerosol Particles in Arctic Amplification” was released within the BAMS May 2019 issue

You may check out the online version here.

18.03.2019 |

Professor Dr. Susanne Crewell was awarded with the Alfred-Wegener-Medal of the German Meteorological Society


Photo: © DMG, Robert Sausen

For her outstanding performances in the research fields of remote sensing of the atmospheric boundary layer and cloud processes, Prof. Dr. Susanne Crewell, University of Cologne, was awarded with the Alfred-Wegener-Medal of the German Meteorological Society.  Her scientific work provides, among others, the basis for their use in modern weather forecast. The laudatory speech was given by Prof. Dr. Andreas Macke from TROPOS Leipzig. The award ceremony was held during the annual conference of German, Austrian and Swiss meteorologists (DACH-Tagung) in Garmisch-Partenkirchen from 18 – 22 March 2019.

20.03.2019 |

Mit dem Forschungsflugzeug ins ewige Eis

20. März 2019

Während in Deutschland allmählich der Frühling Einzug hält, brechen Forscher der Universität Leipzig und des Alfred-Wegener-Instituts in die Arktis auf, um der Klimaerwärmung auf den Grund zu gehen. Im Fokus ihrer Kampagne Arctic aircraft campaign Arctic Boundary Layer Fluxes (AFLUX) sind tiefliegende Wolken am Rand der Meereisfläche und deren Rückkopplung mit bodennahen Prozessen über dem Meereis. Knapp fünf Wochen lang werden die Wissenschaftler des Alfred-Wegener-Instituts, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), des Deutschen Zentrums für Luft- und Raumfahrt, der Universität Clermont-Ferrand in Frankreich sowie der Universitäten Köln und Leipzig von Spitzbergen aus zu einer Reihe von Messflügen aufbrechen.

> Link zur Pressemitteilung


Photo by Dmitry Chechin, AWI.

14.01.2019 - 14.02.2019 |

Melpitz Winter 2019 is testing for for Arctic Summer 2020

From mid-January to mid-February, a field campaign is running at the TROPOS station Melpitz near Torgau to prepare for the MOSAiC expedition. Starting in autumn 2019, the German research icebreaker Polarstern will drift through the Arctic for one year under the direction of the Alfred Wegener Institute (AWI). Supplied by further icebreakers and aircraft, a total of 600 people from 17 countries will take part in the MOSAiC expedition. Science hopes that the expedition will provide new insights into climate change around the North Pole. There is a lack of data from the region, especially in the polar winter, as hardly any researchers have been there at this time of year.

TROPOS will play a leading role in two central measurements: Firstly, a remote sensing container for the entire ice drift will continuously explore the vertical aerosol and cloud distribution using lidar, radar and microwave radiometers. On the other hand, a 90 cubic metre tethered balloon on the fourth of six sections will bring several measuring systems up to an altitude of 1500 metres for two months in summer 2020 in order to measure the Arctic air layers close to the ground as accurately as possible. To ensure that everything runs smoothly there, the Leipzig team is now training the assembly and disassembly of the tethered balloon including the attached measuring technology in Melpitz in winter. Among other things, turbulence, aerosol and radiation measuring devices are tested, which are used in parallel in various combinations on the large captive balloon. In addition to TROPOS, the Institute of Meteorology of the University of Leipzig is also involved in the tests, which will continue the radiation measurements on the 5th section of MOSAiC with a smaller balloon.

The winter weather tests not only provide important insights into whether the technology is robust enough for use in the Arctic. They will also help to embed the measurement data from the balloon in the comprehensive overall measurements. The data from the balloon will be combined with the stationary instruments on the ground and with remote sensing data. In Melpitz, TROPOS has been studying the atmosphere for over 25 years, which is a great help in assessing the quality of the balloon data. In concrete terms, this involves questions such as: Are in-situ aerosol measurements near the ground representative of the atmospheric boundary layer? How exactly can the characteristic vertical distributions of the aerosol be determined? Does the dynamic boundary layer structure correlate with the vertical profiles of the aerosol in terms of concentration, mass and chemical composition, as well as the radiation profiles? How important is the comparison with remote sensing data of the aerosol profiles?

The MOSAiC expedition will thus not only provide new insights into soot and air pollution in the Arctic, but also into the role of particles and clouds in global warming around the North Pole. Since 2016, the Collaborative Research Centre TR 172 “Arctic Amplification” of the German Research Foundation (DFG) has been investigating why the Arctic is warming much more than the rest of the Earth and how much climate change in the Arctic affects the weather in Europe. In addition to the University of Leipzig, the research network also includes the universities of Bremen and Cologne, the Alfred Wegener Institute, the Helmholtz Centre for Polar and Marine Research (AWI) and the Leibniz Institute for Tropospheric Research (TROPOS) in Leipzig.


In addition to the measurement of meteorological standard parameters such as pressure, temperature, humidity and wind, which are also necessary for the safe operation of the balloon, two different payloads are available for turbulence. With these systems smallest wind and temperature changes are measured, which are important for the vertical exchange and the mixing of the atmosphere.

With a newly developed box, which contains various measuring instruments, data on the contamination of the Arctic with aerosol particles can be obtained. These include two particle counters which can detect the smallest particles with a diameter of 10 nanometres and which are used to find out where these small particles are formed from gases in the Arctic. Another device measures the size distribution of larger particles, from which the total mass of fine dust can then be calculated. Furthermore, the concentration of soot particles is measured in order to draw conclusions about their transport routes and to better understand their influence on the Arctic climate.

Two newly developed cloud water and filter collectors will be tested on a balloon for the first time as part of this campaign. These water samples and filters will later be evaluated in the laboratory with high-precision sensors which would be much too heavy for use on the balloon.

A key function in Arctic reinforcement is played by low-lying clouds. By means of the radiation measurements we want to characterize the cooling at the upper edge of the cloud in order to better understand how this cooling affects the dynamics and thus the service life of the cloud. Furthermore, it is possible to investigate under which conditions clouds in the Arctic have a warming or cooling effect on the ground.

Media articles (chronological):
>Expedition ins ewige Eis
(ARD-Mittagsmagazin, 30.01.19, 13:00 Uhr)

>Polarstern-Expedition – Leipziger Forscher trainieren für größte Arktis-Mission aller Zeiten
(MDR-Fernsehen, 28.01.2019, 11:00/14:00/21:40 Uhr)

>Expedition MOSAiC – Forschungsschiff lässt sich im Polareis einfrieren
(MDR-Aktuell (Radio), 24.01.19, 6:53/7:53/8:53 Uhr)

Photos by Tilo Arnhold

12.11.2018 - 14.11.2018 |

2nd (AC)³ Science Conference on Arctic Amplification

Our 2nd (AC)³ Science Conference on Arctic Amplification was held in Bremerhaven from 12 to 14 November, 2018.

Over 110 participants met at Klimahaus Bremerhaven for discussing about the results of the first three years of (AC)³. Well-known international guests presented their work during keynote lectures. The research on Arctic Amplification was presented in various oral presentations mostly by PhD students and young PostDocs and almost 50 scientific posters in five sessions according to the (AC)³ clusters. The “(AC)³ Distinguished Young Investigators Prize” was awarded to three PhD students. Congratulations!

26.09.2017 |

First vernissage of paintings from ACLOUD & PASCAL

A first exhibition of paintings by the graphic designer and illustrator Kerstin Heymach has been shown during the celebration of the 25th anniversary of AWI Potsdam. She accompanied the scientists as part of the team to Longyearbyen and Ny-Ålesund at Spitsbergen in May-June 2017. In the tradition of earlier expedition drawers, her pastels, drawings, sketches, photos and interviews illustrate the beauty of the Nordic landscapes and the difficult work of the researchers and team spirit.

This “Documentary drawings of a scientific expedition to the Arctic” will be published in 2017 and the book can be now ordered (;

18.09.2017 |

DFG status report of German National Committee SCAR/IASC published. More information can be found at DFG website

02.08.2017 |

The EOS (AC)³ overview paper Wendisch et al., 2017 was recently published in the printed August EOS magazine, page 22 – 26.

31.07.2017 |

PR released from AGU for the paper “Increasing frequency and duration of Arctic winter warming events” co-authored by (AC)³ member A. Rinke  (link to paper

24.05.2017 |

On the site “Outreach” we have summarized the most interesting articles of the campaings ACLOUD and PASCAL chronologically.

18.05.2017 |

ACLOUD – Aircraft measurements with Polar 5 & 6 at Longyearbyen/Svalbard



ACLOUD blog:

Further news and flight documentation can be found at our website (here).

PASCAL – Ship measurements with RV Polarstern

Or you may follow us on Twitter #arktis17

18.05.2017 |

We are very pleased that the artist Kerstin Heymach is accompanying our ACLOUD campaign in Longyearbyen/Svalbard. She will look at our often technical and scientific work from another point of view with drawings, pictures and documentation of the field work of artic scientists.

Expeditions-Zeichnen auf Spitzbergen

Ab 29. Mai 2017 nimmt Kerstin Heymach als Zeichnerin für einen knappen Monat an der (AC)³-Expedition auf Spitzbergen/Svalbard teil.

Sie begleitet zeichnerisch, fotografisch und textlich Wissenschaftler der beteiligten Unis Leipzig, Bremen, Köln, des Instituts für Troposphärenforschung (TROPOS) und des Alfred-Wegener-Instituts (AWI) bei ihrer Flugzeug-Kampagne ACLOUD und damit verknüpften Forschungen in Longyearbyen und Ny Alesund.

Sie betreibt dazu einen WordPress-Blog: Wer virtuell ohne kalte Füße mitkommen will: Wer soziale Medien mag, gönnt vielleicht der Seite: ein like und kann auch hier dabei sein.

Kerstin würde sich freuen, wenn Ihr den Blog auch in Eure Communities teilt bzw. weiterschickt.

Expedition drawing on Spitsbergen

Kerstin Heymach will take part, as a droughtswoman, in the (AC)³ Expedition on Spitsbergen/Svalbard for nearly a month, starting from May 29th, 2017.

She accompanies scientists of the contributing universities of Leipzig, Bremen, Cologne, the Institute for Tropospheric Research (TROPOS) and of the Alfred Wegener Institute (AWI) on their aircraft campaign ACLOUD and related research work in Longyearbyen and Ny Alesund by drawing, taking photographs and writing texts.

For that purpose she writes a WordPress blog. For those who want to virtuelly come with her without getting cold feet: Fans of social media could perhaps give a like to the site:  to join her.
Kerstin would be glad if you shared  or passed on this blog to your communities.

Kerstin Heymach
Kerstin Heymach
Kangia Eisfjord Grönland 2004
Kangia Eisfjord Grönland 2004
18.05.2017 |
11.05.2017 |
13.03.2017 |

First balloon tests in Melpitz

Our researches are currently testing their equipment and instruments for the tethered balloon measurements at the TROPOS measurement site in Melpitz, Germany. These tests were also attended and reported by a journalist from “Sächsische Zeitung”. The online arcticle can be found here. The tethered balloon experiment will be conducted during the ice station experiment ABEX within the expedition PASCAL in the Arctic in summer 2017.

Launch of tethered balloon.
Launch of tethered balloon.
Lifted TROPOS balloon mounted with several measurement probes.
Lifted TROPOS balloon mounted with several measurement probes.
TROPOS balloon with circumhorizontal arc.
TROPOS balloon with circumhorizontal arc.
Turbulence probe.
Turbulence probe.
Wind probe.
Wind probe.
Broadband radiation probe
Broadband radiation probe
23.01.2017 |

At the Faculty of Physics and Geosciences the following Junior Professorship has to be filled starting on 1 October 2017:

W1 Junior Professorship Arctic Climate Change (with tenure track leading to W2).

Further information can be found here.

17.01.2017 |

Wendisch et al. recently published an article in EOS on “Understanding Causes and Effects of Rapid Warming in the Arctic” introducing the (AC)³ project. The Article can be downloaded on

24.11.2016 |

The Call for Abstracts for the 1st (AC)³ Science Conference on Arctic Amplification in Bremen, Germany is open from now on until 15 January 2017. Further details can be found here.

27.10.2016 |

Our (AC)³ member Klaus Dethloff, AWI Potsdam, is co-author of a paper recently published in Nature Climate Change: Nonlinear response of mid-latitude weather to the chanching Arctic.

Abstract: Are continuing changes in the Arctic influencing wind patterns and the occurrence of extreme weather events in northern mid-latitudes? The chaotic nature of atmospheric circulation precludes easy answers. The topic is a major science challenge, as continued Arctic temperature increases are an inevitable aspect of anthropogenic climate change. We propose a perspective that rejects simple cause-and-effect pathways and notes diagnostic challenges in interpreting atmospheric dynamics. We present a way forward based on understanding multiple processes that lead to uncertainties in Arctic and mid-latitude weather and climate linkages. We emphasize community coordination for both scientific progress and communication to a broader public.

Reprinted by permission from Macmillan Publishers Ltd: Nature Climate Change, advance online publication, 27 10 2016 (doi:10.1038/nclimate3121).

28.09.2016 |

(AC)³ was officially endorsed by YOPP – The Year of Polar Predicition.

05.09.2016 |

Our (AC)³ members Marion Maturilli and Annette Rinke hold a lecture on “Arctic Climate Change” at the Potsdam Summer School “Dealing with Climate Impacts”. Further information can be found here.

13.07.2016 |

A further award for an outstanding scientist: The Royal Society announced their new members in April 2016, one of them is the Bremer Professor John Philip Burrows from the Insitute of Environmental Physics of the University of Bremen. Further information and a (german) PR can be found here.

27.05.2016 |

Our correponding member Prof. Klaus Dethloff has been elected as a new member of the Leibniz-Soziatät in Berlin. Further information can be found here.

01.07.2016 |

The „Sächsische Zeitung“ (SZ) has published an article on the upcoming Polarstern cruise PS106 in May 2017 within (AC)³ . The article in SZ is available here.

24.06.2016 |

Manfred Wendisch has been invited to give presentations about our (AC)³ Arctic research activities in the framework of the „Lange Nacht der Wissenschaften“ in Leipzig. These presentations were also intended for childrens. Further information can be found here.

02.06.2016 |

The “Leipziger Volkszeitung” (LVZ) has published an article on the recent Kick-off Meeting of (AC)³ at Kloster Nimbschen, Grimma. download here

28.11.2015 |

Journalists from the “Sächsische Zeitung” will give journalistic support to our PASCAL ship cruise PS108 on RV Polarstern. The research editorial team will cover news on the campaign preperations and the Arctic expedition – as a journalist and a “assistant researcher”. Further informoation can be found here.

20.11.2015 |

Great news! The Deutsche Forschungsgemeinschaft (DFG) has approved 15 new SFBs and SFB/TRs including (AC)³. PR can be found here.


19.10.2020 |

#4 Arctic Sea Ice and the MOSAiC Campaign
Lecturer: Gunnar Spreen
Date: Monday, October 19, 2020 10:00 – 11:00 a.m., online

07.10.2020 - 09.10.2020 |

(AC)³ Kick-off meeting phase II in Cologne

The Kick-off meeting for the second phase of (AC)³ will take place close to Cologne from October 7 – 9, 2020.

Further information will follow soon.

06.10.2020 - 09.10.2020 |

(AC)³ PhD Kick-off meeting phase II in Cologne

The PhD Kick-off meeting for the second phase of (AC)³ will take place close to Cologne from October 6 – 9, 2020. Furthermore, there will be the possibility to extend the PhD Kick-off after the end of the (AC)³ Kick-off meeting on October 9 to elaborate and strenghten collaborations among PhD students and early career scientists.

Further information will follow soon.

07.09.2020 |

#3 Feedback Mechanisms
Lecturer: Johannes Quaas
Date: Monday, September 07, 2020 10:00 – 11:00 a.m., online

28.08.2020 - 16.09.2020 |

Airborne campaign MOSAiC ACA takes place in Longyearbyen, Svalbard, from 28 August until 16 September 2020. (AC)³ partners from Unis Leipzig, Cologne, and Bremen, from AWI and Deutsches Zentrums für Luft- und Raumfahrt (DLR) are involved.

(AC)³ is a major German player within the international MOSAiC consortium in which 17 nations are involved. (AC)³ will lead two of the planned airborne campaigns (MOSAiC-Airborne observations in the Central Arctic, MOSAiC-ACA) using the Polar 5 and Polar 6 aircraft of AWI to complement the observations on RV Polarstern. The airborne campaigns are scheduled to take place in March/April and in August/September 2020. Projects A03, B03, B04, C01 will be involved in these airborne campaigns.

The general scientific goal of the MOSAiC ACA 2020 summer campaign is to study the impact of clouds on Arctic amplification, look at air mass transformation processes, and collect data on sea ice distribution in the inner Arctic during summer-time conditions. More specifically, the campaigns aim to obtain comprehensive data sets of a diversity of atmospheric parameters including cloud and aerosol particles and of the energy (turbulent, radiative) and momentum fluxes through clouds. These data will help to quantify the role of clouds in the lower Arctic atmosphere over the Northern Fram Strait. Similar to the previous (AC)³ campaigns ACLOUD (2017), PAMARCMIP (2018), and AFLUX (2019), our strategy is to measure above, in, and below clouds with a large suite of sensors for in situ and remote sensing observations. Using the collected data, it will become possible to better understand the seasonal variability of energy and momentum fluxes, cloud characteristics, and cloud-related processes, since the previous campaigns were carried out in late winter and early summer. Furthermore, we will be able to better investigate clouds and their formation processes over the Arctic Ocean, and to identify the role of aerosol particles and turbulent eddies in cloud processes. This includes the measurements of aerosols (fine dust) and turbulent eddies. For these purposes, a comprehensive suite of instrumentation is installed on Polar 5 including a nose boom with a five-hole probe, a Lidar, a photometer, a cloud radar, as well as other remote sensing instruments to measure the radiation scattered and emitted by clouds, and finally, in-situ cloud probes and a drop sounding system.

03.08.2020 |

#2 Clouds and Radiation
Lecturer: Kerstin Ebell
Date: Monday, August 03, 2020 10:00 – 11:00 a.m., online

The lecture starts with a short motivation on why clouds are important in the (Arctic)
climate system. But when talking about clouds, which properties are actually
important? And how can we use remote sensing measurements to reveal the secrets
of clouds? This will be illustrated by a few examples. We will then have a look at
clouds and their interaction with radiation. In particular, we will focus on their impact
on the surface radiative fluxes. Do Arctic clouds have a cooling or a warming effect at
the surface? How does the cloud radiative effect vary across the Arctic? This lecture
will provide some insights into cloud properties, remote sensing, radiation and the
special cloud characteristics in the Arctic which is one of the key topics in (AC)³.

Online lesson announcement

06.07.2020 |

#1 Arctic Climate System

Date: Monday, July 06, 2020 10:00 – 11:00 a.m., online
Topic: Arctic Climate System
Lecturer: Manfred Wendisch
The lecture starts with a short motivation, why it is so important to study the fascinating processes driving the Arctic climate system. Then, a historical overview of the exploration of the Arctic is given, including famous ship expeditions starting 500 years ago until today. The next part includes a summary of current climate changes (sea ice, snow cover, ocean biology, near-surface air and upper ocean water temperatures, permafrost, sea level). Further on, the talk describes the interlinked and complicated feedback processes within the Arctic climate system with two major topics: clouds and meridional transports. In the end a brief summary is given.
Recommended Literature: “The Arctic Climate System”, by Mark C. Serreze and Roger G. Barry, Cambridge, 2005

16.06.2020 |

Vortragsreihe Exkurs

Die Arktis verschwindet! – Wie wir der Eisschmelze auf die Spur kommen
Prof. Dr. Susanne Crewell

NEW DATE: 16 June 2020

Der Klimawandel erwärmt die Erde. Doch warum erhöht sich die Temperatur in der Arktis schneller als in anderen Regionen? Während sich global die bodennahe Temperatur um etwa ein Grad erhöht hat, sind die beobachteten Temperaturänderungen in der Arktis mehr als doppelt so hoch. Zeitgleich wird das Meereis dünner und in der Fläche weniger.

exkurs-Video: „Die Arktis verschwindet!” von Prof. Susanne Crewell

Weitere Informationen:

11.06.2020 - 12.06.2020 |

Dear Doctoral Candidates, dear PIs of the Graduate School “LGS-CAR”, dear colleagues,

on  11 and 12 June 2020 the training module “Effective radiative forcing due to aerosol-cloud interactions” will be held ONLINE in the framework of the “Leipzig Graduate School on Clouds, Aerosols and Radiation”.


All doctoral candidates are highly welcome to participate.


For the members of the LGS-CAR participation is mandatory and awarded with 2 graded credit points (online examination).


Please save the date.


The detailed programme you can find enclosed here.


With kind regards,

Beate Richter

10.06.2020 |

(AC)³ PhD Welcome online meeting on 10 June 2020, 10:00-13:00 (link will follow soon).

02.06.2020 - 03.06.2020 |

HALO-(AC)³ Kick-off meeting in Leipzig

The Kick-off meeting for the upcoming HALO-(AC)³ campaign in spring 2021 will take place in Leipzig from Jun3 2 – 3, 2020. Meetings in smaller groups would be also possible on 4 June in the morning.

Further information will follow soon.

13.05.2020 |

We would like to invite you to an online CCA Overview Meeting via the zoom link on 13 May 2020 starting 11:00 – 12:00. All 4 CCA leader would give an overview talk to inform our new PhDs and Postdocs in particular. This meeting will be recorded and will be made available via intranet.

02.12.2019 - 04.12.2019 |


It has been a while since we all met to discuss the data analysis of ACLOUD. Now additional measurements from AFLUX are available.
Therefore, we propose a scientific workshop to continue and strengthen the interaction between the different measurement groups and the link to modelling activities.

Please note the following dates in your calender.
Begin: Monday    02.12.2019 start at noon 13:00
End:   Wednesday   04.12.2019 until noon 12:00

Monday and Tuesday will be dedicated to ACLOUD/AFLUX data. This gives us at least 1 1/2 days and time for deep discussion. We hope these days will fit to your schedules and will allow a fruitful discussion.
On Wednesday morning we plan to talk about the upcoming MOSAiC airborne activities with Polar 5. Since the situation for the airborne activities changed dramatically, it is important to revisit the scientific idea and possible flight plans.

Further information will be announced later.

11.09.2019 - 12.09.2019 |

The evaluation of (AC)³ by DFG which is essential for the decision of phase II will take place in Leipzig from 11 – 12 September 2019.

Further information on details of the evaluation for (AC)³ members can be found here.

03.06.2019 - 05.06.2019 |

Location: Maritim – Hotel & Congress Centrum Bremen

After the first “Workshop on Airborne Activities in the Arctic: Science and Prospects” performed in Leipzig, 5-6 October 2017, we would like to invite you to a follow-up meeting. There are two focus objectives of this workshop: to generally review the current status of plans for airborne campaigns in the Arctic for the years to come (including collaborations), and to more specifically plan airborne efforts related to MOSAiC and (AC)³.

Further information can be found here.

16.05.2019 - 17.05.2019 |

A workshop on possible career paths after doing a PhD will be held in Leipzig from 16 to 17 May 2019.

At the end of the workshop, information and instructions for the (AC)³ evaluation in September 2019 will be given to the PhD students.

> schedule

> instructions for the evaluation

07.04.2019 - 12.04.2019 |

Session on Clouds, moisture, and precipitation in the polar regions during EGU 2019

There will be a co-organized session on “Clouds, moisture, and precipitation in the Polar Regions: Sources, processes and impacts”

> direct link to the session

15.01.2019 - 17.01.2019 |

PI Planning meeting phase II of (AC)³ and General Assembly

The PI planning meeting for discussion about the second phase of (AC)³ will take place in Bremen from January 15 – 17, 2019.

Further information will follow.

12.11.2018 - 14.11.2018 |

2nd (AC)³ Science Conference on Arctic Amplification

12 – 14 November 2018: Bremerhaven, Germany

It is planned to start the conference with an ice breaker on Monday, 12 Nov, evening. Subsequently there will be also a PhD student event.

Further information can be found here.

22.10.2018 - 24.10.2018 |

PASCAL conference (SynArc)

22 – 24 October 2018: Delmenhorst, Germany

Synergy of physical, biological, and biogeochemical Arctic observations – From the Polarstern expedition PS106 towards MOSAiC

Further information will follow.

03.07.2018 - 04.07.2018 |

PI Planning meeting phase II

The PI planning meeting for discussion about the second phase of (AC)³ will take place in Leipzig from July 3 -4, 2018.

Further information will follow.

28.06.2018 |

Halo-(AC)³ planning workshop

A first Halo-(AC)³ planning workshop for will take place in Berlin, 28 June 2018.

Further information will follow.

28.05.2018 - 01.06.2018 |

“Advancing MOSAiC Science” workshop

The Multidisciplinary driftings Observatory for the Study of Arctic Climate (MOSAiC) Science workshop will take place from May 28 – 01 June, 2018 at the Alfred Wegener Institute in Potsdam.

Further information can be found here.

12.03.2018 - 06.04.2018 |

PAMARCMiP campaign

Polar Airborne Measurements and Arctic Regional Climate Model Simulation Project (PAMARCMiP) starting on March 12 to April 6 2018, Station North, Greenland.

06.03.2018 - 08.03.2018 |

(AC)³ General Assembly 2018 in Leipzig

The 1st annual (AC)³ General Assembly (GA) meeting will take place in Leipzig from 6 – 8 March, 2018 (noon – noon).

Further information here.

There will be additional and supplementary meetings and breakout groups on the following dates:

  • ACLOUD meeting: 5 – 6 March 2018 @ Prager Str. 34, LIM
  • Xcutting breakout groups: 6 March 2018 @ Augustusplatz, Uni Leipzig, 9-11:30 am
02.02.2018 |

Ocean subgroup meeting

2 February 2018, 13:00 – 16:00 @ HGF Geschäftsstelle Berlin, Anna-Louisa-Karsch-Straße 2, 10178 Berlin

27.11.2017 - 28.11.2017 |

27 – 28 November 2017: University of Cologne, Cologne

The 2nd annual (AC)³ General Assembly (GA) meeting will take place in Cologne from November 27 – 28, 2017.

The (AC)³ community will present their scientific highlights from 2017. During breakout group discussion, the (AC)³ participants will report and discuss on onging collaborations with other Cluster groups and upcoming campaigns.

Meeting agenda and additional information ( PDF ).

20.11.2017 - 21.11.2017 |

20 – 21 November 2017: Leipzig

Workshop “ACLOUD & PASCAL model-data synergy”

In order to fully exploit the (AC)³ observations – here with a focus on the first field campaign results
from the ACLOUD & PASCAL campaigns, but open for additional ideas – we plan a dedicated workshop to bring together ACLOUD & PASCAL scientists (observations side) and modellers (from high-resolved / LES modelling to global climate modelling scale), as well as other interested (AC)³ scientists.
A preliminary workshop 14 October 2016 in Leipzig with participants just from different groups
from Universität Leipzig and TROPOS underlined the potential of, and the interest in, such activities.
We plan a first exploratory workshop on this topic a few months after the ACLOUD & PASCAL  campaigns but early enough to still steer the work of (AC)³ PhD candidates in both, modelling and observations fields, and early enough to accomplish meaningful science in the sense of joint  publications across institutes.
We will call for participation from colleagues who really intend to collaborate on specific model-data
synergy projects (in the sense of a workshop, not a conference).

06.11.2017 - 08.11.2017 |

WORKSHOP: Arctic snow, sea ice properties and interaction with the atmosphere

Dates: 6th – 8th of November 2017

Location: AWI Bremerhaven – Glashaus, building F (Bussestraße 24)


On behalf of the Transregional Collaborative Research Center TR 172 “ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC )³“ we cordially invite you to attend the Topical Workshop on “Arctic snow and sea ice properties and interaction with the atmosphere” which will take place in Bremerhaven, Germany from 6 to 7 November 2017. One aim of the topical workshop is to strengthen the goals of the upcoming aircraft campaign PAMARCMiP (April 2018). A preparation meeting of PAMARCMiP will followed the workshop from 7 to 8 November.


Snow and sea ice albedo are essential to quantify the Arctic energy budget. Only small changes in surface albedo can trigger feedback mechanisms which enhance the Arctic sea ice loss. However, the snow and sea ice albedo are influenced by a multitude of parameters, such as snow grain size, black carbon concentration, surface roughness, the presence of leads and melt ponds, snow and sea ice thickness and the presence of clouds. Therefore, the local optical and physical properties of snow and sea ice have to be well characterized. Especially, aerosol particles including black carbon may alter the snow optical properties but still raise scientific questions like: What are the most relevant sources of aerosol particles contribution to the
reduction of snow albedo? How are aerosol particles transported into the Arctic and deposited to the surface? How aerosol particles interact with the cloudy atmosphere and are scavenged or modified along the transport path? These questions can be answered only by a collaborative effort of different types of measurements and modeling activities that together will capture the full picture of snow-atmosphere interactions.


Abstract (1/2 page) submission until: 31 August 2017

Abstract submission to: Andreas.Herber[at]

The number of participants will be limited to 30 people.

Organization Committee: Andreas Herber, Marco Zanatta, André Ehrlich


Monday 6. Nov. 2017 (12:00 – 20:00)

Key Note Speaker: Marie Dumont
Invited Speakers: Evi Jäkel, Larisa Istomina, Marcel Nicolaus

SESSION II Evening POSTER SESSION with drinks and finger food

Tuesday 7. Nov. 2017 (09:00 – 17:00)

Key Note Speaker: Björn Hallvard Samset
Invited Speakers: Bernd Heinold, Makoto Koike, Henrik Skov


Late Afternoon: Visit of Schifffahrtsmuseum and joint dinner

Wednesday 8. Nov. 2017 (09:00 – 12:00)


Afternoon: Visit of research vessel POLARSTERN

04.10.2017 - 06.10.2017 |

4 – 6 October 2017: Albertina, University of Leipzig

4 October: ATM Graduate School  >> Preliminary Agenda (PDF)

5 – 6 October: HALO-(AC)³ Workshop “Sharpening the Science objectives of HALO-(AC)³

We are planning to apply HALO (High Altitude and Long-Range Research Aircraft) in the framework of the envisioned second phase of (AC)³ in March-April of either 2020 (during MOSAiC) or 2021. The objective will be to measure air mass transformations along their way from the inner Arctic to the open Arctic Sea. In particular, vertical profiles observations of meteorological, aerosol, cloud, and radiative energy budget parameters and their transformations along meridional air mass transports over sea ice has been conducted with a positive outcome. However, it is now time to specify and sharpen the scientific objectives of this mission and to write a White Book summarizing the aims. For this purpose we are planning a topical workshop.

Further information will follow soon.

24.05.2017 - 20.07.2017 |

Physical feedback of Arctic PBL, Sea ice, Cloud And AerosoL (PASCAL) with RV Polarstern on cruise leg PS106.1 and PS106.2 starting on May 24 to July 20 2017 from Bremerhaven to Longyearbyen and Tromsö.

You may check out where Polarstern is on:

Weekly cruise reports from Polarstern are available on:

Polarstern blog:

22.05.2017 - 28.06.2017 |

Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) starting on May 22 to June 28 2017, Longyearbyen/Svalbard.

Further information can be found on You may also follow our ACLOUD blog on

22.04.2017 - 23.04.2017 |

Come and visit RV Polarstern!

Within the Science Year 2016*17 the research vessel Polarstern, operated by the Alfred Wegener Institute, will be open for the public on 22 and 23 April.

Date and Time

Saturday, 22 April 2017, 11 a.m. until 5 p.m. (ship will close at 4 p.m.)
Sunday, 23 April 2017, 10 a.m. until 4 p.m. (ship will close at 3 p.m.)

Further details can be found at AWI website.

26.03.2017 - 28.03.2017 |

26 – 28 March 2017: University of Bremen, Germany. 1st (AC)³ Science Conference.

The conference will summarize the scientific results obtained during the first year of the
Transregional Collaborative Research Center TR 172 on Arctic Amplification (AC)³, and discuss them in context with the international research community. Distinguished guest speakers will talk about recent highlights and current hypotheses in the field of Arctic climate research. Talks and posters will be presented in five sessions. The “(AC)³ Disthinguished Young Investigators Prizes“ will be awarded. The conference is supposed to promote scientific exchange and identify key tasks to be addressed in near-future Arctic climate research.

 A conference flyer can be downloaded here ( outside / inside ).

Further information

The final conference agenda is available here.

Each conference participant will recieve a printed conference booklet including all general information and abstracts at the registration desk. You may also download a digital pdf version in advance. At the conference site WLAN will be available (for further information please ask the registration desk).

You may register for the evening talk by Sebastian Gerland with subsequent (AC)³ reception seperately using the following link:³-reception/

We are looking forward to welcoming you to our conference in Bremen!

19.03.2017 - 25.03.2017 |

19 -25 March 2017: Hyytiälä, Finland.

The winter school is an advanced course intended for graduate students and researchers who want to receive
up-to-date knowledge on the observation and modeling of clouds and precipitation, with a specific focus on
Arctic and high-latitude clouds. The course is structured around a combination of lectures and hands-on
experience using data from research-grade radars (US DOE ARM and ACTRIS), in situ sensors and state-ofthe-
art models. The course topics include: cloud and precipitation observations (cloud radars, lidars, solar
and microwave radiometers, in situ sensors), cloud modeling, precipitation formation, boundary layer

The winter school announcement, registration and application deadline can be found here.

14.12.2016 - 16.12.2016 |

14 – 16 December  2016: Youth Hostel Riehl, Cologne. PhD Worhshop.

The two-day workshop theme is ‘Getting Started’ and includes topics such as time, self and project management. It will provide you with relevant and helpful tools for your writing process. On the third day, Friday, December 16th, you will have the opportunity to spend some time together, share your experiences within and outside your cluster and possibly make a visit to the observatory for cloud evolution in Jülich. This second part of the workshop will be prepared and organised by you. Robert Rauterkus as one of the docs’ representatives will be coordinating this part of the workshop. Please contact him with your ideas and suggestions on this part (r.rauterkus[at] For details on the workshop, please see below.

Workshop: Getting Started

Trainer: Aleksandra Skoric

Date: December 14th – 16th

Place: Youth Hostel Riehl, Cologne

Accommodation: Youth Hostel Riehl, Cologne

Registration for workshop via mail to Annette Drost  (idrost[at] More details will follow soon.

12.12.2016 |

12 December 2016: University of Leipzig. Colloquia on “Arctic Climate Change” by Deutsche Meteorologische Gesellschaft (DMG). Abstracts and further information can be found here for download (only german).

01.12.2016 - 02.12.2016 |

1 – 2 December 2016: Wissenschaftszentrum, Potsdam. 2nd General Assambly (GA) Meeting. Futher information can be found here.

21.11.2016 - 22.11.2016 |

21 – 22 November 2016 : University of Bremen, Meeting Room U1050, IUP Building NW1, Bremen. Preparation Workshop ACLOUD. Further information can be found here.

01.11.2016 |

1 November 2016: University of Leipzig, Faculty of Physics and Earth Sciences, Linnéstr. 5, Leipzig. Colloquia on “Arctic Climate Change”.

18.10.2016 - 19.10.2016 |

18 – 19 October 2016: University of Bremen. PARMACIMP kick-off meeting.

17.10.2016 - 18.10.2016 |

17 – 18 October  2016: University of Leipzig/TROPOS, Leipzig. ATM “Cloud droplet concentration”. An ATM outline is available here and further programe information can be found in a pdf file. Further ATMs with (AC)³ specific focus will be added in the future.

03.10.2016 - 07.10.2016 |

3 – 7 October 2016: Kjeller (Norway), Ny-Ålesund Atmosphere Flagship work group meetings from NySMAC (Ny-Ålesund Science Managers Committee)

14.07.2016 - 17.07.2016 |

14 – 17 July  2016: University of Leipzig/TROPOS, Leipzig. PhD Workshop on Introduction to Linux/Unix.

09.06.2016 |

9 June 2016, 15:15 – TROPOS, Leipzig. Prof. Dr. Annica Ekman gives a talk “Arctic climate response to regional aerosol emission changes between 1980 and 2005” within the scope of the Leipziger Meteorologisches Kolloqium.

02.06.2016 - 02.06.2016 |

1 June – 2 June 2016 (AC)³ PhD Kick-off Meeting at Kloster Nimbschen, Grimma. Further information can be found here.

30.05.2016 - 01.06.2016 |

30 May – 1 June 2016 (AC)³ Kick-off Meeting at Kloster Nimbschen, Grimma. Further information can be found here.

02.05.2016 |

2 May 2016 – Bremerhaven: Planning Meeting Polarstern PS106

24.04.2016 |

24 April 2016, 10:00 – Faculty of Physics and Earth Science, Leipzig. Prof. Dr. Johannes Quaas gives a Sunday lecture on “Luftverschmutzung, Wolken und der Klimawandel – Global und in der Arktis” (details).

31.03.2016 |

31 March 2016, 15:15 – TROPOS, Leipzig. Dr. Peggy Achtert gives a talk “An overview of atmospheric measurements during recent Arctic cruises with the Swedish icebreaker Oden” within the scope of the Leipziger Meteorologisches Kolloqium. The abstract can be found here.

16.02.2016 - 17.02.2016 |

16 -17 February 2016 – Leipzig. Further information can be found here.

28.01.2016 - 29.01.2016 |

28 -29 January 2016 – Sopot, Poland (link)