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Bolivia campaign – particle nucleation and urban influence at 5240 masl

Aerosol particle nucleation and urban influences are studied at the Chacaltaya GAW Station (CHC) in the Bolivian Andes (16°21.014'S, 68º07.886'W, 5240 masl). The Chacaltaya mountain directly faces a plateau of 3800 masl in the south and west and is separated from the Amazon basin by higher peaks in the north and east. Research groups from La Paz, Stockholm, Helsinki, Innsbruck, Granada, Leipzig, and Karlsruhe combine their instruments to characterize the aerosol from November 2017 to June 2018. Focus of our contribution is the molecular composition of gas- and particle phase on the mountain and in the La Paz – El Alto metropolitan area.

HyICE - Aerosol-cloud studies in Hyytiälä

Aerosol-cloud interaction is a first time focus of a field campaign at the SMEAR-II station in Hyytiälä, Finland. The campaign is led by the Department of Physics of the University of Helsinki, with contributions of 8 research teams from Canada, Finland, Germany, Sweden, Switzerland, and the UK. From March to May 2018, IMK-AAF is measuring aerosols and ice nucleating particles with newly developed instruments. The measurements have now successfully been started and will last until mid-May, in order to cover the transition from winter to early summer conditions and to assess the contribution of new particle formation and biosphere activity to the INP abundance in the boreal forest area.

Aurora Australis
MARCUS - Southern Ocean Boundary Layer Aerosol in Focus

The Measurements of Aerosols, Radiation, and Clouds over the Southern Ocean (MARCUS) field campaign is acquiring comprehensive observations of aerosols including cloud condensation nuclei and ice nucleating particles in the Southern Ocean boundary layer. The second ARM Mobile Facility is currently installed on the Australian Antarctic supply vessel Aurora Australis as it routinely travels between Hobart and the Antarctic. MARCUS has a strong link with the SOCRATES campaign targeting on clouds in the Southern Ocean and their connection to air-sea exchange processes. IMK-AAF is participating in MARCUS by monitoring the biological aerosol with the WIBS4 instrument.

MARCUS Campaign Description
SOCRATES - Southern Ocean Clouds in Focus

A research project called the Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study (SOCRATES) is currently conducted in Tasmania, Australia. The US research aircraft NSF/NCAR HIAPER is deployed to unravel the secrets of clouds over the Southern Ocean. These clouds are frequently misinterpreted by current climate models, and in-situ investigations like SOCRATES play a vital role in enhancing modeling and forecasting capabilities in this area. The IMK-AAF is providing cloud microphysics measurements with the PHIPS probe. 

SOCRATES Project Overview
IMK-AAF welcomes AvH Postdoctoral Research Fellow

In September 2017, Dr. Nsikanabasi Umo joined IMK-AAF following his prestigious Alexander von Humboldt (AvH) Postdoctoral Research Fellowship Award. His work will focus on understanding the ice nucleation abilities of combustion and other aerosol particles at mixed-phase and cirrus cloud conditions. During October he is leading first experiments with the worldwide unique AIDA Cloud Simulation Chamber at IMK-AAF.

Nsikanabasi Umo obtained his PhD in 2014 from the University of Leeds, United Kingdom, in the field of Atmospheric Sciences. He is grateful to the AvH Foundation, Germany, for the award, which he considers a golden opportunity for his career advancement.

KIT International also welcomes Nsikanabasi Umo as new AvH Fellow.

Characterisation of Urban Aerosol in Stuttgart

In July and August 2017 we participated in a joint research project on the three-dimensional observation of atmospheric processes in cities (3DO) by dedicated characterisation of the urban background aerosol in the Rosenstein Park in downtown Stuttgart, Germany. This study allows the combination of very detailled meteorological observations with comprehensive characterisation of aerosol chemistry and physics.

Three-dimensional Observation of Atmospheric Processes in Cities
 AIDA Scheme
20 Years Aerosol and Cloud Research with AIDA

On May 22nd, 1997, our institute celebrated the formal opening of the new aerosol and cloud chamber facility AIDA. After about two years of construction and technical runs, the first scientific campaign started on May 11th, 1997, and investigated heterogeneous chemistry on soot aerosols. Since then, a number of 5 to 10 campaigns was conducted every year, covering topics of trace gas chemistry, heterogeneous chemistry, aerosol formation, aerosol optical properties, polar stratospheric cloud formation as well as formation, growth, morphology and radiative properties of ice crystals in tropospheric clouds. The aerosol-cloud research with AIDA is also the topic of a recent KIT podcast (in German). We are grateful to all our national and international collaboration partners who contributed and still contribute to many of the AIDA campaigns.

HDO/H2O isotopic fractionation in simulated cirrus clouds

The first experimental determination of HDO/H2O isotopic fractionation factors for ice deposition in simulated cirrus clouds for temperatures betwen 190-233 K could be achieved in the AIDA aerosol and cloud chamber (Lamb et al., PNAS 2017). In collaboration between the University of Chicago, PTB, and KIT unique measurement techniques for water isotopes were developed and applied for dedicated cirrus cloud simulation experiments. A detailed box model analysis including wall effects resulted in equilibrium fractionation factors and kinetic isotope effects with a weaker temperature dependence than extrapolations of previous work suggested. These results are fundamental for inferring processes on Earth and other planets from water isotopic measurements.

View from Jungfraujoch Research Station
Measurements at the High Altitude Research Station Jungfraujoch

During the INUIT-CLACE campaign in January and February 2017, international teams collaborate at the Jungfraujoch Research Station (3571 m, Switzerland) to investigate aerosol-cloud processes and cloud microphysics in the mixed-phase cloud regime. KIT contributes single particle mass spectrometer measurements of aerosol particles and cloud ice residuals, as well as measurements of ice nucleating particle (INP) concentrations by taking aerosol filter samples for later offline INP analysis with an immersion freezing method.

Integration of European atmospheric simulation chambers in the new EUROCHAMP-2020 infrastructure project

Between December 2016 and 2020 the EU invests ~9 Mio € to further integrate 16 simulation chamber and 4 calibration facilities. This includes the AIDA aerosol and cloud chamber facility of KIT. Trans national access to these facilities is substantially supported. For details contact us or see: www.eurochamp.org.

Ice active nucleation cites successfully identified on K-Feldspar

Scientists of IMK-AAF, in cooperation with researchers of the KIT Laboratory of Electron Microscopy (LEM) and University College London (UCL) have succeeded in identifying the unique features on K-Feldspar responsible for its high ice nucleation efficiency. As reported in Science magazine (DOI: 10.1126/science.aai8034), they combined electron microscopy observations with molecular modeling to determine for the first time the atomic nature of this important inorganic ice nucleating particle. They showed that ice starts to grow on the specific crystal faces with (100) orientation that only occur at defects (steps, cracks, and crevices) on the surface of feldspar particles.

Maiden flight of KIT developed instrument onboard the US NCAR C-130

The KIT in-house development PHIPS-HALO was chosen as the only non-US instrument to participate in the NSF funded airborne campaign ARISTO taking place in Colorado, USA. ARISTO is a unique platform for testing innovative and novel technologies in the field of atmospheric research. This year’s platform, the C-130, is well-known for its capabilities to do research flights under harsh conditions. The first flight of the campaign was performed targeting ongoing forest fires in the Rocky Mountains area. The flight was a success for the whole payload and especially for the KIT PHIPS-HALO.

Environmental Award 2015 of the Sparkasse Karlsruhe-Ettlingen received by Natascha Savic

She received the award for her Master thesis “Influence of biodiesel fuel composition on morphology and microstructure of particles emitted from Diesel engines”. Her results are expected to be useful for the development of after treatment devices and the understanding of the atmospheric behaviour of soot particles as well as their health effects.  (http://www.umweltstiftung-karlsruhe.de/sparkassen-umwelt-preis)

Field campaign to compare AeroTram data with results of stationary measurements near Leopoldshafen

AeroTram findings of unexpected high annual averaged particle number concentrations near Leopoldshafen are investigated in a joint effort by IMK-TRO and IMK-AAF. A measurement container equipped with various gas and particle sensors including most advanced mass spectrometers is deployed near Leopoldshafen to identify the nature and potentially the origin of the high particle concentrations observed by the instrumented AeroTram (http://www.aero-tram.kit.edu/).


The scientific research at AAF is part of the exhibition "GLOBALE: Exo-Evolution" at Center for Art and Media (ZKM, Karlsruhe, Germany). From 31.10 2015 to 28.02.2016 two exhibits, “High speed video recordings of freely levitated freezing droplets” and “Ice crystals growing on feldspar mineral in electron microscope” can be seen in the ZKM, Atrium 8+9. The exhibits show high resolution video recordings of microphysical processes responsible for nucleation and growth of ice in atmospheric clouds. The exhibition opening takes place on Friday, October 30th, 2015 at 7:30 pm.

KIT GRACE student contributes to FIN03

During September 2015, U.S. and German teams of atmospheric ice nucleation research collaborate at the Storm Peak Laboratory, Steamboat Springs, Colorado, to intercompare methods for sampling ice nucleating particles from ambient air. This activity called FIN03 is the final major experimental activity within the Fifth International Ice Nucleation Workshop (FIN). The KIT PhD student Thea Schiebel is participating in this activity as part of her 3 month visit to the Colorado State University which is supported by the KIT Graduate School for Climate and Environment (GRACE) 

The Fifth International Ice Nucleation Workshop (FIN)

This workshop is the most comprehensive ever held concerning atmospheric ice nucleation studies. Three phases include intercomparison of single particle mass spectrometers (FIN01, Nov 2014) and of ice nucleation measurement methods (FIN02, Mar 2015), both held at the KIT AIDA cloud chamber, and intercomparison of methods for sampling ice nucleating particles from ambient air at Storm Peak Laboratory, Steamboat Springs (FIN03, Sep 2015). The FIN activities are supported by NSF, DOE-ASR and DFG (Research Unit INUIT).

Research Infrastructure Project AIDA-2

The ongoing AIDA-2 project includes the construction of a new lab building, the renovation of the AIDA facility, the installation of an aerosol mass spectrometry lab, and the construction of a novel dynamic cloud chamber. Building construction and AIDA renovation are making good progress. Reopening of the AIDA facility is planned for September after the installation of a new liquid gas supply system.

contour plot
Aerosol Simulation Web Site Released by IMK-AAF A web based version of the extensively validated detailed numerical aerosol process model COSIMA-F has been made freely available to the public. This code describes the structural properties and dynamical evolution of  ramified aggregates, e.g. freshly emitted soot, based on fractal scaling laws. However, it can also be operated like a conventional aerosol behaviour code when dealing with compact aerosol particles. Several entirely editable default scenarios are available. For more information or conducting your own simulations please visit the COSIMA homepage
Ice nucleation by cellulose aerosol

Searching for the ice nucleating particle (INP) types in the atmosheric aerosol is still a major challenge of aerosol-cloud-climate research. Scientists from the Karlsruhe Institute of Technology, the Meteorological Research Institute in Tsukuba, Japan, and the University of Bielefeld have identified cellulose as an important source of atmospheric INPs, as reported  in Nature Geoscience 8, 273-277 (2015) .

International Symposium on Ultrafine Particles

The effects of ultrafine particles, the smallest constituents of airborne particulate matter, on air quality, atmospheric processes, climate, and human health are by far not finally investigated to proven evidence. The 5th EFCA Ultrafine Particles Symposium  will reflect the most recent scientific progress in the field and aims to contribute to the dialogue with policymakers in Europe.  The symposium takes place on May 4 - 5 in Brussels, Belgium. It is co-organized by KIT and chaired by the head of IMK-AAF, Prof. Thomas Leisner.

Polar 6
Arctic Aircraft Mission

From April 23rd, 2014 until May 23rd, 2014 IMK-AAF participates in the RACEPAC campaign (http://www.uni-leipzig.de/~racepac/index.html) located in Inuvik and Tuktuyaktuk, Northwest Territories, Canada.

Cloud experiments in Japan

For the first time, cloud researchers from the KIT AIDA team participated in laboratory cloud simulation experiments at the Meteorological Research Institute (MRI) in Tsukuba, Japan. From October 1- 11, 2013, they closely collaborated with Dr. Masataka Murakami and his team for ice nucleation studies at the MRI dymanic cloud chamber. These experiments nicely extend and complement ice nucleation studies which are performed within the DFG funded Research Unit INUIT (FOR 1525).

International intercomparison of atmospheric hygrometers (AquaVIT2).

In April 2013 50 scientists from 6 different countries participated with 36 different hygrometers in a blind refereed intercomparison including traceable references. The intercomparison covered conditions simulating the UT/LS (186-233 K, 0.2-1300 ppmv) with static periods and dynamic changes including ice clouds. AquaVIT-2 will help reducing instrument uncertainties in order to better quantify the important role of atmospheric water vapor in weather and climate systems.

The Teramobile laser container being installed outside the AIDA experimental hall
Laser plasma – Ice cloud Interaction: Publication in PNAS

Together with the Teramobile Collaboration the interaction of fs- laser filaments with clouds was investigated. As detailed in a recent article in the Proceedings of the National Academy of Science of the United States http://dx.doi.org/10.1073/pnas.1222190110, the laser induced plasma channels did not influence ice nucleation in mixed phase clouds but had a remarkably strong effect on ice clouds at temperatures below the limit of homogeneous freezing. Read more: http://www.kit.edu/visit/pi_2013_13037.php

UFP Symposium
International Symposium on Ultrafine Particles

The effects of ultrafine particles, the smallest constituents of airborne particulate matter, on air quality, atmospheric processes, climate, and human health are by far not finally investigated to proven evidence. The 4th EFCA Ultrafine Particles Symposium will reflect the most recent scientific progress in the field and aims to contribute to the dialogue with policymakers in Europe.  The symposium takes place on May 16 - 17 in Brussels, Belgium. It is co-organized by KIT and chaired by the head of IMK-AAF, Prof. Thomas Leisner.

AIDA team participates in ISOCLOUD project

The joint NSF/DFG project ISOCLOUD investigates the water isotope fractionation by combining AIDA cloud simulation experiments with process modelling studies. In October 2012, the project partners achieved simulta- neous measurements of H2O, HDO, and H2(18)O both in the gas phase and the condensed phase. First results show the HDO fractionation to be in agreement with Rayleigh distillation assumptions. In March 2013, further AIDA experiments are planned to measure fractionation factors in cold cirrus clouds.

In-cloud measurements at Jungfraujoch station (3568 m asl)

18.01.2013. Within the DFG-funded project ISI a team from IMK-AAF is currently investigating the microphysical properties of cloud droplet and ice particles at the high altitude research station Jungfraujoch in Switzerland. The aim of the study is to improve the current understanding of the formation processes and structure of mixed-phase clouds.

Review on laboratory heterogeneous ice nucleation experiments

In an extensive review article (Hoose and Möhler, ACP 2012), results on ice nucleation by various aerosols, such as dust, soot, organic acids and biological particles, from AIDA and many other laboratory studies are compiled and intercompared. The aim is to provide an easily accessible overview of historic and recent results in this active field of research. One of the figures of this article has also been  adapted for the draft of the "Clouds and Aerosols" chapter of the IPCC Fifth Assessment Report (AR5).

UAV-Workshop Participants
Interdisciplinary Workshop on Unmanned Aerial Systems

The interdisciplinary workshop "Challenges and chances of new Unmanned Aerial Systems (UAS)" took place on September 13-15, 2012, in Karlsruhe and was organized by the IMK-AAF in cooperation with the IPF and FBTA. The workshop received startup funding from the KIT Competence Area “Earth and Environment”. The participants from various fields such as atmospheric, environmental and geo science, photogrammetry, mathematics, computer science and civil engineering discussed recent develop- ments in sensor and UAS technology and evaluated the opportunities arising from new cooperations.

KIT-Labor auf der Zugspitze

Nine partners of the DFG-funded project ACRIDICON (Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems) and the AIDAmobile team join on mount Zugspitze during a three week, ground based field campaign starting 17.09.2012. Instruments designed for future missions aboard the High Altitude and LOng Range Research Aircraft HALO will be installed both on the summit and at the environmental research station UFS to characterize cloud microphysical and radiative properties and aerosol-cloud interaction.

AIDA chamber
Results of MUCHACHAS SOA aging campaign published in PNAS

IMK-AAF scientists and their AIDA facility participated in the Multiple Chamber Aerosol Chemical Aging Study (MUCHACHAS) demonstrating that chemical conversions induced by hydroxyl radicals, the dominant atmospheric oxidant, significantly increase the concentration of first-generation biogenic secon- dary organic aerosol (SOA).  The principal findings from MUCHACHAS have now been published in the Proceedings of the National Academy of Sciences of the USA (link to PNAS paper).

AWI Polar5
AIDA team participates in VERDI

Ice particles in Arctic boundary layer clouds are in the focal point of the German scientific expedition VERDI. The main goal of VERDI is to understand the role of these clouds in the strong warming observed in the Artic over the last decades. The clouds are probed by a novel set of instruments onboard the Polar 5 research aircraft, which is operated by the Alfred Wegener Institute (AWI). VERDI is based in Inuvik, NWT, Canada, for research flights over the Beaufort Sea. 

New focus on ice nucleation research

The formation of the ice phase in tropospheric clouds has multiple impacts on the hydrological cycle and the climate system. Many aspects of ice nucleation induced by a minor subgroup of the atmospheric aerosol system, so-called ice nuclei, remain unclear and will be addressed by the Research Unit INUIT, which was recently established by the German Research Foundation (DFG). In two projects, the IMK-AAF will contribute comprehensive laboratory and modeling studies on ice nucleation.


First correlated measurements of cloud particle shape and light scattering using PHIPS

IMK-AAF disclosed its pioneering Particle Habit Imaging and Polar Scattering (PHIPS) probe in the Journal of Atmospheric Measurement Techniques (October 12, 2011). Developed for the German research aircraft HALO, it simultaneously measures the 3-D morphology and corre- sponding optical and micro- physical parameters of individual cloud particles. The paper outlines the concept and design of PHIPS and dis- cusses preliminary results of two ice cloud campaigns con- ducted in the AIDA chamber.

Aerosol and Cloud Measurement Campaign (Zugspitze)

New sampling inlets and continuous aerosol measurements have been installed at the environmental research station Schneefernerhaus (UFS) in summer 2011. The IMK-AAF investigated aerosol - cloud interactions in warm clouds with focus on bioaerosol, soot, water budget in cooperation with the IMK-IFU on three plattforms (UFS, Zugspitze, and ultralight research aircraft) during a 2-week summer campaign.

International workshop IN2clouds

The International Workshop on Ice Nucleation in Tropospheric Clouds (IN2clouds) was organized by the IMK-AAF within the framework of the Helmholtz Virtual Institute on Aerosol- Cloud Interactions. The workshop took place in Ettlingen on May 23-25, 2011, offering the opportunity to discuss recent and ongoing research activities in the field of aerosol-cloud-climate interactions among the VI-ACI project partners and invited experts from Europe, Israel, U.S.A. and Japan.

SID3 probes cirrus clouds over the South Central U.S.

The Small Ice Detector (SID3) of IMK-AAF has been successfully deployed on board the NASA WB-57F aircraft during the Mid-latitude Airborne Cirrus Properties Experiment (MACPEX) in April 2011. SID3 single particle data will give unique contributions to the question on the microphysical nature of the smallest ice crystals and how important these particles are for the radiative forcing.

Isabelle Steinke
IMK-AAF PhD student wins FameLab contest

On February 25th, FameLab Baden-Württemberg took place in Karlsruhe for the first time: FameLab is a compe-tition where students have only 3 minutes to explain a complex scientific subject and convince the audience with their creative performance. Among the participants was Isabelle Steinke, PhD student at IMK-AAF. Learn more about what experiments at the AIDA cloud chamber have in common with Germany’s Next Topmodel:  http://www.youtube.com/watch?v=jgsv_xEsfYY

Ice growth on meso- spheric nanoaerosols Controlled ice formation on sub 10-nanometer conden- sation nuclei has been observed for the first time under mesospheric conditions at the Atmospheric Nano- science group. The laboratory experiment took place in a cooled linear radiofrequency- ion trap in an ice-oversatura- ted environment, where free iron-oxide particles with growing ice shells could be stored for several seconds. In the near future systematic investigations of ice nucle- ation probabilities and growth rates of mesospheric relevant materials are planned.
Growth of levitated ice crystals in Paul trap

The nucleation and growth of pristine ice crystals attached to a frozen water droplet levitated in the Electro-Dynamic Balance (EDB, also known as “Paul trap”) has been recently observed at IMK-AAF. The newly developed environmental EDB allows for controlling the humidity and temperature profiles inside the trap, thus providing a unique tool for studying the evolution of single ice crystals.

Glassy aerosols and ice nucleation

Organic aerosols are ubiquitous in the atmos-phere. At low temperatures they are known to become glassy, that is, amorphous, non-crystalline solids. AIDA cloud chamber experiments demonstrate heterogeneous nucleation of ice on glassy citric acid particles (Murray et al., Nature Geoscience 2010).

"Dust beats biology for cloud ice formation"

In the first global modelling study of heterogeneous ice nucleation by biological particles, Hoose et al. (http://iopscience.iop.org/1748-9326/5/2/024009/fulltext) show that typical atmospheric bacteria, fungal spores and pollen concentrations are too low to make a significant impact for cloud ice and precipitation formation. The research is featured in a news article on environmentalresearchweb. org.

Dr. Corinna Hoose
Helmholtz-University Young Investigators Group at IMK-AAF

Dr. Corinna Hoose and her Young Investigators Group “Aerosol effects on cloud ice, precipitation and climate“ will work on improved parameterizations for aerosol-cloud interactions in numerical models on different scales. A special focus is on cloud ice formation.

Marsilius Kolleg
Marsilius-Project on "Climate Engineering"

IMK-AAF participates in the new Marsilius Project “The Global Governance of Climate Engineering” which focuses on options and risks in dealing with climate change by technological means. The Marsilius Kolleg was recently established at the University of Heidelberg as a Centre for Advanced Study to promote interdisciplinary dialogue and research.
More about the Climate Engineering Project

Atmospheric Nanoscience
Nanoscience Campaign at BESSY II

The IMK-AAF Atmospheric Nanoscience Group joins a three week measurement campaign at the synchrotron source BESSY II in Berlin. Research objective is the identification of polymorphs of nanometric ironoxide cloud nucleation seeds. Nanoaerosols ablated from meteorites are expected to play a crucial role in the formation of mesospheric noctilucent clouds.

Aerosol and Cloud Microphysics Measurements at UFS

In February, IMK-AAF conducted a feasibility study at the environmental research station Schneefernerhaus (UFS). The aim of the study was to show that the UFS is well suited to measure aerosol - cloud interactions in natural clouds.